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UBC Theses and Dissertations

Wood versus substitute materials in residential construction Neilson, Ronald William 1971

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WOOD VERSUS SUBSTITUTE MATERIALS IN RESIDENTIAL CONSTRUCTION by RONALD WILLIAM NEILSON B.Sc.F., U n i v e r s i t y of T o r o n t o , 1966 A THESIS SUBMITTED IN PARTIAL FULFILMENT OF THE REQUIREMENTS FOR THE DEGREE OF MASTER OF FORESTRY i n t h e Department of F o r e s t r y We a c c e p t t h i s t h e s i s as c o n f o r m i n g t o t h e r e q u i r e d stand'ard THE UNIVERSITY OF BRITISH COLUMBIA J u n e , 1971 In present ing th i s thes i s in p a r t i a l f u l f i lmen t o f the requirements fo an advanced degree at the Un iver s i t y of Bri t i sir Columbia, I agree that the L ibrary sha l l make it f r ee l y ava i l ab le for reference and study. I fu r ther agree that permission for extens ive copying of th i s thes i s fo r s cho la r l y purposes may be granted by the Head of my Department or by his representat ives . It i s understood that copying or pub l i ca t i on o f th i s thes i s f o r f i nanc i a l gain sha]1 not be allowed without my wr i t ten permiss ion. Department of -Fioyeft^y  The Un ivers i ty of B r i t i s h Columbia Vancouver 8, Canada Date 7un.e. I f i t T A B S T R A C T R e s i d e n t i a l c o n s t r u c t i o n has been a f o c u s o f a t t e n t i o n i n N o r t h A m e r i c a i n r e c e n t y e a r s . R i s i n g c o n s t r u c t i o n c o s t s , and g r o w i n g s o c i a l p r e s s u r e s t o meet h o u s i n g needs -,have r e s u l t e d i n a c o n c e n t r a t e d . e f f o r t by government and i n d u s t r y t o d e v e l o p new and impro v e d b u i l d i n g methods. Wood frame c o n s t r u c t i o n t e c h n i q u e s , a l t h o u g h t r a d i t i o n a l i n Canada, a r e n o t g u a r a n t e e d a f d o m i n a n t p o s i t i o n i n t h e f u t u r e . W i t h t h e h i g h volume o f wood p r o d u c t s consumed i n r e s i d e n t i a l c o n s t r u c t i o n , t h e f o r e s t i n d u s -t r i e s have a l a r g e s t a k e i n t h i s m a r k e t . Two a s p e c t s o f d e c l i n i n g wood use i n h o u s i n g .have b e e n . i n v e s t i -g a t e d i n t h i s t h e s i s : (1) c h a n g i n g methods of c o n s t r u c t i o n ; and (2) s u b -s t i t u t i o n o f non-wood b u i l d i n g m a t e r i a l s f o r wood. A l t h o u g h r e c e n t p r o j e c t i o n s i n d i c a t e a s t r o n g h o u s i n g demand t o 1980, t h e t y p e s o f d w e l l i n g s c o n s t r u c t e d a r e e q u a l l y , i m p o r t a n t , single^'--f a m i l y u n i t s consuming t h e g r e a t e s t volume of wood p r o d u c t s , and h i g h - r i s e a p a r t m e n t s t h e l e a s t . A s t r o n g t r e n d toward apartment c o n s t r u c t i o n has been e v i d e n t s i n c e 1950, f o s t e r e d by r a p i d u r b a n p o p u l a t i o n g r o w t h , m o r t -gage i n v e s t m e n t , p r e f e r e n c e s , t h e h i g h c o s t o f u r b a n l a n d , and t h e l o w e r c o s t o f r e n t a l accommodation. I t i s e s t i m a t e d t h a t t h e l o s s o f wood p r o -d u c t s m a r k e t s from 1960 t o 1969 due.to t h i s t r e n d was 1,355 m i l l i o n bd. f t . of lumber, 245,075,000 s q . f t . o f plywood and v e n e e r , and.151,068,000 s q . f t . o f b u i l d i n g , b o a r d . F u n c t i o n a l s u i t a b i l i t y i s p r o b a b l y t h e most i m p o r t a n t , d e t e r m i n a n t of m a t e r i a l s c h o i c e . T r a d i t i o n , a f a c t o r w h i c h has f a v o u r e d wood, frame b u i l d i n g , is l o s i n g i t s i n f l u e n c e . A v a i l a b i l i t y o f m a t e r i a l s and v e r t i -c a l i n t e g r a t i o n a r e n o t s i g n i f i c a n t f a c t o r s , i n Canada. Upward t r e n d s i n t h e p r i c e o f wood p r o d u c t s , p r i c e i n s t a b i l i t y , and.the much h i g h e r , r e s e a r c h and development e x p e n d i t u r e s i n competing i n d u s t r i e s can be e x p e c t e d t o r e -s u l t i n an a c c e l e r a t e d r a t e o f s u b s t i t u t i o n o f o t h e r m a t e r i a l s f o r . wood. A l t h o u g h wood p e r f o r m s w e l l i n many a p p l i c a t i o n s , i t s - : : c o m b u s t i b i l i t y has been a g r e a t d i s a d v a n t a g e f o r c o n s t r u c t i o n u s e s . B u i l d i n g codes have s i g -n i f i c a n t l y l i m i t e d i t s u s e , b u t have also•,hindered, t h e i n t r o d u c t i o n o f new b u i l d i n g t e c h n i q u e s , and p r o d u c t s made of s u b s t i t u t e m a t e r i a l s . P r o d u c t s made of aluminum, . p l a s t i c s , s t e e l , and n o n - m e t a l l i c m i n e r a l s have had v a r y i n g d e grees of s u c c e s s i n ..the h o u s i n g m a r ket. Num-. erou s developments s u c h as'; aluminum and s t e e l s t r u c t u r a l s y s t e m s , p l a s t i c and m e t a l s a n d w i c h p a n e l s , and p r e c a s t c o n c r e t e b u i l d i n g s y s t e m s , o f f e r p o t e n t i a l c o m p e t i t i o n t o wood frame methods. V e r t i c a l i n t e g r a t i o n w i t h , the . b u i l d i n g i n d u s t r y , and more a c t i v e p r o m o t i o n o f , and. t e c h n i c a l a s s i s t a n c e i n wood frame methods may h e l p curb t h e t r e n d t o apartment c o n s t r u c t i o n . .Greater e f f o r t s t o redu c e c o s t s , h i g h -e r r e s e a r c h and development e x p e n d i t u r e s , i n c r e a s e d a c t i v i t y i n market r e -s e a r c h , and g r e a t e r e f f o r t s t o r e d u c e p r i c e f l u c t u a t i o n s a r e n e c e s s a r y t o p r e v e n t h i g h e r r a t e s o f s u b s t i t u t i o n . M o r e . e f f o r t s h o u l d be c o n c e n t r a t e d on t h e development o f f o r e i g n m a r k e t s , b o t h t o . h e l p r e d u c e p r i c e f l u c t u a -t i o n s , and t o p r o v i d e a l t e r n a t e m a r k e t s . f o r . t h o s e l o s t .through s u b s t i t u t i o n . Page ABSTRACT. . i i LIST OF TABLES v i LIST OF FIGURES . . . v i i ACKNOWLEDGEMENT . v i i i INTRODUCTION 1 TRENDS IN HOUSING 5 H i s t o r i c a l Developments i n H o u s i n g . 5 Sou r c e s of H o u s i n g Demand 5 ( i ) Net f a m i l y h o u s e h o l d f o r m a t i o n . . 6 ( i i ) Net n o n - f a m i l y h o u s e h o l d f o r m a t i o n 6 ( i i i ) U n d o u b l i n g 7 ( i v ) Net r e p l a c e m e n t s . . . . . . . . 7 (v) V a c a n c i e s . 8 P r o j e c t i o n s o f H o u s i n g Demand ,;, 8 Trends i n Dwellingv*Types 12 F a c t o r s I n f l u e n c i n g Types of D w e l l i n g s C o n s t r u c t e d 18 ( i ) Urban p o p u l a t i o n growth 18 ( i i ) Consumer p r e f e r e n c e s . 20 ( i i i ) I n v e s t o r p r e f e r e n c e s 21 ( i v ) Land c o s t s 26 (v) Incomes and h o u s i n g c o s t s 26 CONSUMPTION OF WOOD PRODUCTS IN HOUSING 32 FACTORS INFLUENCING CHOICE OF MATERIALS IN RESIDENTIAL CONSTRUCTION 41 T r a d i t i o n 41 A v a i l a b i l i t y 43 P r i c e o f M a t e r i a l s 43 Page R e s e a r c h and Development. . 60 F u n c t i o n a l v S u i / t a ^ h i l i t y . 67 B u i l d i n g Codes. . . . . . . . . . . . . . . . . 81 P r e f e r e n c e s 84 C o r p o r a t e L i n k s 86 PENETRATION OF SUBSTITUTES FOR WOOD INTO THE HOUSING MARKET . . . . 90 Aluminum. . . 90 S t e e l ; . . . 94 P l a s t i c s 98 N o n - m e t a l l i c M i n e r a l s 107 Combined M a t e r i a l s 112 INDUSTRIALIZED BUILDING 116 C l a s s e s o f I n d u s t r i a l i z e d B u i l d i n g . 118 O n - s i t e B u i l d i n g W i t h L i m i t e d Use o f Components 119 P r e f a b r i c a t e d Component Packages 120 S e c t i o n a l House C o n s t r u c t i o n 122 I n f l u e n c e o f B u i l d i n g Codes 125 European B u i l d i n g Systems . 127 C o n c r e t e B u i l d i n g Systems i n Canada. . 129 M e t a l , P l a s t i c , and S t r u c t u r a l C l a y Systems 132 The R o l e s o f Competing M a t e r i a l s . 135 CONCLUSIONS: IMPLICATIONS FOR THE FOREST INDUSTRIES 137 BIBLIOGRAPHY. . . • 143 T a b l e Page 1. E s t i m a t e d h o u s i n g c o n s t r u c t i o n r e q u i r e m e n t s , 1956 -§>80. . . . 9 2. A c t u a l volume o f h o u s i n g c o n s t r u c t e d t o 1969 10 3. Components of h o u s i n g demand bas e d on demographic t r e n d s . . . 11 4. S t a r t s by t y p e of d w e l l i n g , a l l a r e a s 14 5. C o m p l e t i o n s by t y p e o f d w e l l i n g , a l l a r e a s . 15 6. NHA - Approved l o a n s by CMHC f o r new h o u s i n g . . .1 23 7. Mortgage l o a n s a p proved by l e n d i n g i n s t i t u t i o n s , by t y p e o f d w e l l i n g . . . 24 8. Wood us e d p e r u n i t i n s i n g l e - f a m i l y houses i n s p e c t e d by th e F e d e r a l H o u s i n g A d m i n i s t r a t i o n , 1962 & 1968 36 9. Wood used p e r u n i t by c o n s t r u c t i o n c h a r a c t e r i s t i c s ; . , - 1962' • • 37 10. Wood p r o d u c t s consumed p e r d w e l l i n g u n i t . 38 11. I n t r a - m u r a l R & D e x p e n d i t u r e s i n Canada, by i n d u s t r y . . . . 63 12. E x t r a - m u r a l R & D e x p e n d i t u r e s i n Canada, by i n d u s t r y . . . . 64 13. Funds f o r R & D p e r f o r m a n c e i n t h e U.S.A., by i n d u s t r y . . . . 66 14. Thermal c o n d u c t i v i t y of b u i l d i n g m a t e r i a l s 74 15. Impact n o i s e r a t i n g s u s i n g v a r i o u s f l o o r c o n s t r u c t i o n s on c o n c r e t e . 78 F i g u r e Page 1. H o u s i n g s t a r t s by d w e l l i n g t y p e as p e r c e n t of t o t a l 16 2. H o u s i n g completarons by d w e l l i n g t y p e as p e r c e n t o f t o t a l . . . 1>7 • 3. Indexes of s h e l t e r c o s t and p e r s o n a l d i s p o s a b l e income p e r c a p i t a 28 4. Consumer p r i c e i n d e x e s of s h e l t e r c o s t : r e n t a l v e r s u s home-ownership 30 5. W h o l e s a l e p r i c e i n d e x e s i n Canada 45 6. P r i c e i n d e x numbers o f r e s i d e n t i a l b u i l d i n g m a t e r i a l s i n Canada. . 47 7. I n d u s t r y s e l l i n g p r i c e i n d e x e s 53 8. I n d u s t r y s e l l i n g p r i c e i n d e x e s . 55 9. I n d u s t r y s e l l i n g p r i c e i n d e x e s 56 A C K N O W L E D G E M E N T I w i s h to, acknowledge t h e a s s i s t a n c e and g u i d a n c e p r o v i d e d by my s u p e r v i s o r , Dr.' R. W. Wellwood, t h r o u g h o u t t h e c o u r s e of t h i s s t u d y . I n a d d i t i o n , t h e a u t h o r i s g r a t e f u l f o r t h e c o n s t r u c t i v e comments p r o v i d e d by Dr. D. H a l e y and Dr. J . H. G. Smith o f t h e F a c -u l t y o f F o r e s t r y , and Dr. G. N a g l e o f t h e F o r e s t R e s e a r c h L a b o r a t o r y , Department o f F i s h e r i e s and F o r e s t r y , V i c t o r i a . Thanks a r e a l s o o f f e r e d t o t h e U n i v e r s i t y o f B r i t i s h Colum-b i a f o r t h e f i n a n c i a l a s s i s t a n c e p r o v i d e d o v e r t h e s t u d y p e r i o d . v i l i D u r i n g t h e p a s t few y e a r s , h o u s i n g has been a f o c u s o f a t t e n t i o n i n N o r t h A m e r i c a . As a s u b j e c t w h i c h touches t h e l i v e s o f e v e r y o n e i n one f o r m o r a n o t h e r , r e s i d e n t i a l c o n s t r u c t i o n remains o f g r e a t concern' t o t h e g e n e r a l p u b l i c , a l l l e v e l s o f government, and p r i v a t e e n t e r p r i s e . The p r o b l e m o f h o u s i n g t h e o l d and t h e poor has always been p r e -s e n t , b u t r e c e n t l y , a r i s i n g from r a p i d l y i n c r e a s i n g house p r i c e s , c l a i m s have been made t h a t many m i d d l e - c l a s s p e o p l e can no l o n g e r a n t i c i p a t e own-i n g a c o n v e n t i o n a l l y - s t y l e d s i n g l e - f a m i l y house. C o n t r i b u t i n g s i g n i f i c a n t -l y t o t h e s e r i s i n g p r i c e s have been t h e r i s i n g c o s t o f s e r v i c e d l a n d and mortgage i n t e r e s t r a t e s , c o u p l e d w i t h a l a c k , o f mortgage i n v e s t m e n t f u n d s , w h i c h have, i n t u r n , r e s u l t e d i n a s h o r t a g e o f h o u s i n g a t p r i c e s w h i c h many p e o p l e can a f f o r d . A n t i - i n f l a t i o n a r y measures, such as i n c r e a s i n g t h e p r i m e l e n d i n g r a t e , have a l s o h i n d e r e d t h e house b u i l d i n g e f f o r t and added t o t h e s u p p l y p r o b l e m . These r a t e s a r e now a m e l i o r a t i n g , b u t whe-t h e r t h i s s i t u a t i o n i s temporary o r permanent i s u n c e r t a i n . I n t h e U n i t e d S t a t e s , where t h e " h o u s i n g c r i s i s " has been l i s t e d as t h e number one p r o b l e m , w i t h top p r i o r i t y f o r l e g i s l a t i v e a c t i o n , t h e s i t u a t i o n i s more s e v e r e t h a n i n . C a n a d a , and i s c o u p l e d w i t h , a m a j o r s o c i a l u p h e a v a l . However, i t i s r e c o g n i z e d t h a t , a h o u s i n g p r o h l e m does e x i s t i n Canada, as e x e m p l i f i e d . b y . t h e T ask F o r c e on H o u s i n g ;and Urban Development ( H e l l y e r , 1 9 6 9 ) . R e s u l t i n g f r o m t h i s c o n c e r n o v e r h o u s i n g , t h e v a r i o u s l e v e l s o f government, t h e r e s i d e n t i a l c o n s t r u c t i o n i n d u s t r y , and,major c o n s t r u c t i o n m a t e r i a l s s u p p l i e r s , a r e a l l . a c t i v e l y s e a r c h i n g " f o r new and b e t t e r s o l u t i o n s t o t h e q u e s t i o n of, how t o p r o v i d e a c c e p t a b l e forms o f s h e l t e r a t a r e a s o n a b l e c o s t . A l t h o u g h t h e wood frame house has l o n g been t h e c o n v e n t i o n a l s t y l e o f h o u s i n g i n t h i s c o u n t r y , t h e r e i s no g u a r a n t e e t h a t new c o n s t r u c t i o n t e c h n i q u e s w i l l c o n t i n u e t o p r o v i d e a s u b s t a n t i a l market f o r f o r e s t p r o -d u c t s . I t has b e e n . s a i d . t h a t no one knows w i t h p r e c i s i o n where wood p r o -d u c t s a r e u s e d . However, a number o f e s t i m a t e s a r e a v a i l a b l e , p r i m a r i l y f o r U.S. m a r k e t s , w h i c h do n o t d i f f e r d r a s t i c a l l y from C a n a d i a n m a r k e t s . Muench (1969) r e p o r t e d t h a t r e s i d e n t i a l c o n s t r u c t i o n i n t h e U.S.A. ac c o u n t e d f o r about 35 p e r c e n t o f s o f t w o o d lumber co n s u m p t i o n . I n Canada, a s l i g h t l y h i g h e r p e r c e n t a g e o f lumber i s p r o b a b l y consumed by the h o u s i n g i n d u s t r y . A l i t t l e o v e r h a l f o f the s o f t w o o d plywood used i n t h e U.S.A. e n t e r s r e s i d e n t i a l constriicti©n, whereas i n Canada, an e s t i -mated 23 p e r c e n t i s employed i n h o u s i n g , w i t h an a d d i t i o n a l 25 p e r c e n t g o i n g ' i n t o n o n - c o n t r a c t homes and second home use ( B o w l a n d . e i al. 3 1 9 6 8 ) . A c c o r d i n g t o FAO (1966) , most i n s u l a t i o n b o a r d and*?ab.out h a l f o f the h a r d -b o a r d produced i n t h e U.S.A. i s used i n c o n s t r u c t i o n ( b o t h r e s i d e n t i a l and n o n - r e s i d e n t i a l ) . A l s o about 22 p e r c e n t o f the U.S. p a r t i c l e b o a r d p r o -d u c t i o n went i n t o r e s i d e n t i a l c o n s t r u c t i o n i n 1965 ( L e w i s , 1 9 6 9 ) . A s i m i -l a r s i t u a t i o n e x i s t s m i n Canada, a l t h o u g h a c t u a l f i g u r e s a r e n o t a v a i l a b l e . The above s t a t i s t i c s s h o u l d be s u f f i c i e n t t o i n d i c a t e t h e l a r g e s t a k e w h i c h t h e f o r e s t i n d u s t r i e s have i n r e s i d e n t i a l c o n s t r u c t i o n . The g r a d u a l t r e n d away from t h e use o f lumber i n . r e s i d e n t i a l c o n s t r u c -t i o n i n N o r t h A m e r i c a and e l s e w h e r e has. been documented i n . s e v e r a l s t u d i e s . Tromp and Campredon CL966) have a t t r i b u t e d t h e d e c l i n i n g wood consumption t o f i v e d i f f e r e n t s o u r c e s : . XX) more r a t i o n a l u t i l i z a t i o n of wood; C2) g r e a t e r d u r a b i l i t y o f wood due t o t h e use o f p r e s e r v a t i v e s ; (3) s u b s t i t u t i o n f o r s o l i d wood by wood-based p a n e l p r o d u c t s ; (4) c h a n g i n g methods o f c o n s t r u c -t i o n ; and (5) s u b s t i t u t i o n o f o t h e r (non-wood) b u i l d i n g m a t e r i a l s f o r wood. The f i r s t t h r e e a s p e c t s o f d e c l i n i n g wood use e n t a i l t e c h n o l o g i c a l advan-ces d e v e l o p e d i n an e f f o r t t o overcome problems r e l a t i n g t o wood u s e , and t o l o w e r c o s t s . Such, advances a r e e s s e n t i a l i f t h e f o r e s t i n d u s t r i e s a r e t o r e m a i n c o m p e t i t i v e . The l a s t two a s p e c t s o f d e c r e a s i n g wood consumption i n v o l v e e i t h e r d i r e c t o r i n d i r e c t r e p l a c e m e n t o f wood by s u b s t i t u t e m a t e r -i a l s . I n l i g h t o f t h e t r e n d s toward apartment c o n s t r u c t i o n , and t h e r e -newed i n t e r e s t and a c t i v i t y o f competing b u i l d i n g m a t e r i a l s m a n u f a c t u r e r s i n t h e r e s i d e n t i a l c o n s t r u c t i o n i n d u s t r y , t h e s e two s o u r c e s o f d e c l i n i n g wood con s u m p t i o n a r e of p a r t i c u l a r i n t e r e s t a t t h e p r e s e n t t i m e . The p u r p o s e o f t h i s s t u d y i s t o a s s e s s the c u r r e n t s i t u a t i o n w i t h r e s p e c t t o the use of wood and s u b s t i t u t e m a t e r i a l s i n t h e h o u s i n g i n d u s -t r y i n Canada, t o i d e n t i f y r e c e n t t r e n d s i n m a t e r i a l s u s e , and t o i s o l a t e a n d : d i s c u s s t h o s e f a c t o r s w h i c h have an i n f l u e n c e on t h i s q u e s t i o n . B o t h c h a n g i n g methods o f c o n s t r u c t i o n as r e f l e c t e d by t r e n d s i n d w e l l i n g t y p e s , and d i r e c t r e p l a c e m e n t o f wood by competing m a t e r i a l s , w i l l be i n v e s t i g a t e d . The f i r s t q u e s t i o n , r e l a t i n g t o d w e l l i n g t y p e s and f a c t o r s u n d e r l y i n g r e c e n t t r e n d s , s h o u l d be of i n t e r e s t t o t h e f o r e s t i n d u s t r i e s , b u t t h e i r a b i l i t y t o i n f l u e n c e s u c h t r e n d s i s n e g l i g i b l e . The second q u e s t i o n , r e l a t i n g t o t h e s u b s t i t u t i o n o f o t h e r m a t e r i a l s . f o r wood, i s o f more immediate, i n t e r e s t t o m a t e r i a l s s u p p l i e r s s i n c e i t i s . i n t h i s a r e a t h a t t h e y h a v e . d i r e c t i n f l u e n c e t h r o u g h t h e i r , r e s e a r c h , , p r o d u c t development,. and .marketing....programs . I t i s i n t e n d e d t h a t t h i s s t u d y be based p r i m a r i l y on.the. C a n a d i a n r e s i d e n t i a l c o n s t r u c t i o n m a r ket. However, due t o s i m i l a r i t i e s w i t h the U.S.A., much o f t h e c o n t e n t of t h i s t h e s i s w i l l a p p l y t o a l l - of N o r t h A m e r i c a ; and where C a n a d i a n d a t a . a r e . l a c k i n g , U.S. d a t a may be used as i n d i c a t i v e o f t h e o v e r a l l s i t u a t i o n i n N o r t h A m e r i c a , o r as a b a s i s o f e v a l u a t i n g t h e C a n a d i a n p o s i t i o n . Due t o t h e i m p o r t a n c e o f e x p o r t markets t o t h e Ca n a d i a n f o r e s t i n -d u s t r i e s , t h e s i g n i f i c a n c e of t h e d o m e s t i c market i s sometimes o v e r l o o k e d . A c c o r d i n g l y , i t i s n o t e d h e r e t h a t , o f t h e e s t i m a t e d 2,020,391 M s q . f t . (3/8 i n . ) o f s o f t w o o d plywood produced i n Canada .ink1969, 75 p e r c e n t was s h i p p e d t o d o m e s t i c m a r k e t s , and t h e r e m a i n d e r e x p o r t e d , p r i m a r i l y t o t h e U n i t e d Kingdom and Eu r o p e , and Ja p a n . F o r t h e same y e a r , a p p r o x i m a t e l y 39 p e r c e n t o f t h e t o t a l C a n a d i a n lumber p r o d u c t i o n o f 11,419 MM fbm was consumed by t h e d o m e s t i c m a r k e t , w h i l e 82 p e r cent o f - t h e e x p o r t s went t o the U.S.A. Combined, Canada and t h e U.S.A. consumed 88 p e r c e n t o f Cana-d i a n lumber p r o d u c t i o n i n 1969. The market w i l l be f u r t h e r r e s t r i c t e d t o i n c l u d e " p r i m a r y " h o u s i n g o n l y ( r e s i d e n t i a l c o n s t r u c t i o n i n t e n d e d f o r y e a r - r o u n d o c c u p a n c y ) , and w i l l e x c l u d e s u c h s t r u c t u r e s as summer c o t t a g e s , c a b i n s , s h a c k s , t r a i l e r s and boathouses.. M o b i l e homes w i l l a l s o be c o n s i d e r e d a s e p a r a t e market and w i l l be e x c l u d e d from t h i s s t u d y . TRENDS LN ROUSING A l t h o u g h t h e main d i s c u s s i o n i n t h i s , s e c t i o n f o c u s e s on t r e n d s i n t y p e s o f d w e l l i n g s e r e c t e d , t h e a c t u a l volume of r e s i d e n t i a l c o n s t r u c -t i o n i s a l s o s i g n i f i c a n t i n d e t e r m i n i n g t h e demand <£or wood p r o d u c t s by th e h o u s i n g i n d u s t r y . I t i s t h e r e f o r e a p p r o p r i a t e t o b e g i n w i t h a b r i e f o u t l i n e o f t h e c h i e f s o u r c e s o f h o u s i n g demand, and some r e c e n t p r o j e c t i o n s of t h i s demand i n Canada. H i s t o r i c a l Developments i n H o u s i n g S i n c e W o r l d War I I , Canada's p e r f o r m a n c e i n p r o v i d i n g s h e l t e r has been good i n r e l a t i o n t o i t s g r o w i n g needs and demands f o r h o u s i n g . Never-, t h e l e s s , a s l i g h t l a g i n p r o d u c t i o n r e l a t i v e t o r e q u i r e m e n t s d u r i n g t h e 1961-66 p e r i o d d e v e l o p e d i n t o a s e v e r e h o u s i n g s h o r t a g e i n many p a r t s o f th e c o u n t r y by 1967 (Economic C o u n c i l o f Canada, 1967 and 1969). A major f a c t o r i n t h i s s h o r t a g e was a s e v e r e c u r t a i l m e n t o f h o u s i n g s t a r t s i n 1966 (due l a r g e l y t o a d e f i c i e n c y o f mortgage f u n d s ) a t a t i m e when f a m i l y f o r -m a t i o n s were gr o w i n g a t a h i g h r a t e . The r e s u l t i s t h a t Canada i s e n t e r -i n g a p e r i o d o f i n c r e a s i n g h o u s i n g demand ( f r o m s e v e r a l s o u r c e s ) w h i l e s t i l l f a c e d w i t h a s h o r t a g e w h i c h has d e v e l o p e d d u r i n g the. p a s t decade. So u r c e s o f H o u s i n g Demand The demand f o r h o u s i n g c o n s i s t s o f s e v e r a l components: C i ) n e t f a m i l y h o u s e h o l d . f o r m a t i o n ; ( i i ) n e t n o n - f a m i l y h o u s e h o l d f o r m a t i o n ; ( i i i ) u n d o u b l i n g ; : ( i v ) n e t r e p l a c e m e n t s . ( a c c i d e n t a l l o s s , f a r m abandon-ments , non-farm r e m o v a l s ) ; (y) v a c a n c i e s . Each, of t h e s e f a c t o r s w i l l b e b r i e f l y d i s c u s s e d i n t h e c o n t e x t o f Canada's p r e s e n t h o u s i n g s i t u a t i o n . ( i ) Net f a m i l y h o u s e h o l d f o r m a t i o n T h i s i s t h e most i m p o r t a n t s o u r c e o f new demand f o r h o u s i n g (Dube et at. 3 1957). The p o s t - w a r "baby boom" has l e d t o a s u b s t a n t i a l i n -c r e a s e i n m a r r i a g e s and f a m i l y f o r m a t i o n i n t h e l a t t e r h a l f o f ! t h e 1960's, and t h e t r e n d i s e x p e c t e d t o c o n t i n u e t o 1980 ( I l l i n g , 1967) . The p r o p o r -t i o n o f n e t f a m i l y f o r m a t i o n made up from n e t i m m i g r a t i o n i s q u i t e v a r i -a b l e b u t i s e x p e c t e d t o a v e r a g e 13 p e r c e n t of n e t f a m i l y f o r m a t i o n t o 1980 ( I l l i n g , 1 9 6 7 ) . A l t h o u g h n o t a l l f a m i l i e s form h o u s e h o l d s , i t was e s t i m a t e d t h a t 94.3 p e r c e n t d i d so i n 1961, and t h i s f i g u r e w a s . f o r e c a s t t o i n c r e a s e t o 97.5 p e r c e n t i n 1967 ( I l l i n g , 1 964). ( i i ) Net n o n - f a m i l y h o u s e h o l d f o r m a t i o n T h i s c a t e g o r y . o f h o u s e h o l d f o r m a t i o n i s l a r g e l y a f f e c t e d by the e x -t e n t t o w h i c h young s i n g l e p e o p l e and e l d e r l y i n d i v i d u a l s e s t a b l i s h t h e i r own h o u s e h o l d s (Economic C o u n c i l o f Canada ,-"1967) . S i n c e t h e e a r l y 1950:'s, t h e r e has been a g r e a t u p s u r g e i n n o n - f a m i l y h o u s e h o l d s , h a v i n g r i s e n f r o m about 450,000 i n t h e e a r l y 1950's t o over.vSOO,000 by t h e mid-1960's (Economic C o u n c i l of Canada, 1967). I n t h e 1960-65 period., when f a m i l y f o r m a t i o n was r e l a t i v e l y l o w , t h e a v e r a g e a n n u a l i n c r e a s e i n . n o n - f a m i l y h o u s e h o l d s was 4.9 p e r c e n t , compared t o 1.9 p e r cent, f o r f a m i l y h o u s e h o l d s . I t i s p r e d i c t e d t h a t t h e s e r a t e s o f i n c r e a s e w i l l change t o 2.9 p e r c e n t f o r n o n - f a m i l y h o u s e h o l d s and 2.6 p e r c e n t f o r . f a m i l y h o u s e h o l d s i n t h e 1970-75 p e r i o d ( I l l i n g , . 1 9 6 7 ) . I n t h e p e r i o d t o 1980 j t h e age groups p r o v i d i n g the b u l k o f p e o p l e l i k e l y t o e s t a b l i s h n o n - f a m i l y h o u s e h o l d s w i l l be g r o w i n g s t r o n g l y . ( i i i ) U n d o u b l i n g The i n c r e a s i n g a b i l i t y o f f a m i l i e s l i v i n g i n s h a r e d accommodations to s e t up t h e i r own h o u s e h o l d s i s an i m p o r t a n t . f a c t o r c o n t r i b u t i n g t o h o u s i n g demand. I n t h e e a r l y 1950's, an e s t i m a t e d 10 p e r c e n t o f a l l C a n a d i a n f a m i l i e s l i v e d i n s h a r e d accommodation, b u t by 1965, p r o b a b l y l e s s t h a n f i v e p e r c e n t remained i n t h i s c a t e g o r y . A s i m i l a r r a t e o f un-d o u b l i n g i s a n t i c i p a t e d t o 1980 ( I l l i n g , 1 9 6 7 ) . The r e l a t i o n s h i p between h o u s i n g c o m p l e t i o n s and t h e above t h r e e s o u r c e s o f demand i s g r e a t l y i n f l u e n c e d by g e n e r a l economic c o n d i t i o n s and f a m i l y incomes. ( i v ) Net r e p l a c e m e n t s T h i s s o u r c e of demand can r e s u l t from t h r e e c a u s e s : (1) a c c i d e n t -a l l o s s e s due t o f i r e , f l o o d , and o t h e r n a t u r a l d e s t r u c t i v e f o r c e s ; (2) abandonments o f fa r m d w e l l i n g s a s s o c i a t e d w i t h r u r a l - u r b a n p o p u l a t i o n s h i f t s ; C3) w i t h d r a w a l o f d i l a p i d a t e d non-farm d w e l l i n g s , . o r r e m o v a l s ' f o r e i t h e r . p r i v a t e o r p u b l i c c o n s t r u c t i o n p u r p o s e s f i l l i n g , 1 9 6 4 ) . L o s s e s i n h o u s i n g s t o c k due t o t h e f i r s t , a n d . t h i r d causes above were, r e p o r t e d t o av e r a g e 8,000 u n i t s p e r y e a r i n the..years j u s t p r i o r t o 1957, e q u a l l y s h a r e d by fa r m and non-farm d w e l l i n g s (Dube et al*3 1957). These r e p l a c e -ments a r e c l o s e l y r e l a t e d t o t h e age s t r u c t u r e o f t h e h o u s i n g s t o c k and t h e l i f e e x p e c t a n c y o f d w e l l i n g s , and a r e e x p e c t e d t o be a t l e a s t as h i g h , i n th e f u t u r e as t h e y have been i n the p a s t (Dube et at. 3 1957). Farm aban-donments have u n d o u b t e d l y been s u b s t a n t i a l i n r e c e n t y e a r s , i n c r e a s i n g h o u s i n g demands e l s e w h e r e . A l t h o u g h s u c h movements w i l l c o n t i n u e , t h e i r r e l a t i v e i m p o r t a n c e i s l i k e l y t o d e c r e a s e ( T i l i n g , 19.64). (v) V a c a n c i e s A c e r t a i n p e r c e n t a g e o f v a c a n c i e s i n the t o t a l h o u s i n g s t o c k ' i s r e q u i r e d t o f a c i l i t a t e p o p u l a t i o n m o b i l i t y and a l l o w f o r smooth a d j u s t s ment between, demand and s u p p l y (Economic C o u n c i l o f Canada, 1967). T h i s v a c a n c y r a t e was 3.3 p e r c e n t i n 1951, 2.6 p e r c e n t i n 1955, and f o r p r o j e c -t i o n p u r p o s e s Dube et al. ,(1957) assumed'a r a t e o f 3.3 p e r 1 c e n t . More recent^-l y , I l l i n g . (1964) r e p o r t e d v a c a n c y r a t e s o f 3.5 and 3.9 perscen't i n 1961 and 1963, r e s p e c t i v e l y , and assumed a r a t e o f 4.0 p e r c e n t f o r h i s p r o j e c t i o n s . A s m a l l b u t c o n s i s t e n t demand w i l l o r i g i n a t e from t h i s s o u r c e a s • t h e t o t a l h o u s i n g s t o c k i n c r e a s e s . P r o j e c t i o n s o f H o u s i n g Demand R e c e n t • h o u s i n g demand p r o j e c t i o n s f o r Canada have i n c o r p o r a t e d ' v a r i o u s a s s u m p t i o n s w i t h r e s p e c t t o the s o u r c e s o f demand o u t l i n e d above i n o r d e r t o d e t e r m i n e f u t u r e h o u s i n g r e q u i r e m e n t s . . F o r the' R o y a l Commission on Canada's Economic P r o s p e c t s , Dube et al. (1957) i n c o r p o r a t e d an e s t i m a t e of h o u s i n g r e q u i r e m e n t s t o 1980 i n t h e i r r e p o r t on "Housing and S o c i a l C a p i t a l . " T h e i r p r o j e c t i o n s a r e shown i n T a b l e 1. A c t u a l h o u s i n g p r o d u c e t i o n t o the end o f 1969 has p r o v e n t h e above f i g u r e s - to be c o n s e r v a t i v e . ESTIMATED HOUSING CONSTRUCTION REQUIREMENTS 19.56 - 80 DEMAND FACTORS 1956-60 1961-65 1966-70 1971-75 1976-80 TOTAL (thousands o f u n i t s ) Net F a m i l y F o r m a t i o n 348 414 500 605 683 2,550 Non-Family Household F o r m a t i o n , 66 67 70 78 89 370 R e d u c t i o n o f Crowding 50 50 50 50 50 250 Replacements ' R u r a l - U r b a n Pop. S h i f t s 25 20 5 50 O t h e r Replacements 50 58 66 74 82 330 V a c a n c i e s 20 24. 29 33 38 144 T o t a l 559 633 720 840 942 3,694 (Avg. A n n u a l R e q u i r e m e n t s ) (112) (12.7) (140) (168) (188) S o u r c e : Dube• et al., .1957. H o u s i n g and S o c i a l C a p i t a l . I n T a b l e 2 i s i n d i c a t e d the a c t u a l p e r f o r m a n c e o f t h e r e s i d e n t i a l c o n s t r u c -t i o n i n d u s t r y . Comparing a p p r o p r i a t e f i g u r e s i n T a b l e s 1 and 2, i t i s a p p a r e n t t h a t the a c t u a l p e r f o r m a n c e o f the r e s i d e n t i a l b u i l d i n g i n d u s t r y has ex-ceeded the r e q u i r e m e n t s p r o j e c t e d by Dub£ et al. ( 1 9 5 7 ) . The l a r g e s t s i n g l e ACTUAL VOLUME- OF HOUSING CONSTRUCTED TO 1969 1956-60 1961-65 1966-69 -S t a r t s * 664,486 736,519 705,890 ( A n n u a l Average) (132^897) (147,304) ' (176,472). C o m p l e t i o n s 1 " 669,097 674,481 678,253 ( A n n u a l A v e r a g e ) (133,819) (134,896) (169,563) A s t a r t i's r e c o r d e d ' when t h e f o o t i n g o f the s t r u c t u r e has been i n s t a l l e d . f . . . A c o m p l e t i o n i s r e c o r d e d when a l l p r o p o s e d c o n s t r u c t i o n work'-on a d w e l l i n g u n i t has been p e r f o r m e d . S o u r c e : C e n t r a l Mortgage and H o u s i n g C o r p o r a t i o n , 1969a. Canadian H o u s i n g S t a t i s t i c s 1968. e r r o r i n t h e s e p r o j e c t i o n s has been i n the c a t e g o r y o f n o n - f a m i l y h o u s e d ' h o l d f o r m a t i o n s . D u r i n g the 1961-65 p e r i o d , n o n - f a m i l y h o u s e h o l d s were formed a t a r a t e o f 37,000 p e r y e a r , a r a t e c o n s i d e r a b l y h i g h e r t h a n the e s t i m a t e d 13,400 p e r y e a r '(for a t o t a l o f 67,000 f o r the f i v e - y e a r p e r i o d ) g i v e n i n T a b l e 1. I t s h o u l d a l s o be n o t e d t h a t a c t u a l p r o d u c t i o n i n t h e y e a r s 1961-66 was n o t s u f f i c i e n t , r e s u l t i n g i n a s e v e r e s h o r t a g e of• hous-•. i n g by 1967 (Economic C o u n c i l o f Canada, 1967 and 1969). More r e c e n t l y , t h e C a n a d i a n Government has v o i c e d i t s commitment t o t h e c o n s t r u c t i o n o f one m i l l i o n new d w e l l i n g u n i t s i n t h e 1969-74 p e r i o d , an ave r a g e o f 200,000 u n i t s p e r y e a r ( C a n a d i a n B u i l d i n g , 1971). C o n s i d e r i n g t h e 210,415 s t a r t s i n 1969 and 190,528 s t a r t s i n 1970, t h e h o u s i n g i n d u s t r y has thus f a r k e p t pace w i t h t h i s p r e d i c t i o n . , W i t h o v e r 200,000 s t a r t s p r e d i c t e d f o r 1971 (Ca n a d i a n B u i l d i n g , 1971), i t i s p r o b a b l e t h a t t h e commitment t o the con-s t r u c t i o n o f one m i l l i o n d w e l l i n g u n i t s o ver the f i v e - y e a r p e r i o d t o 1974 w i l l be met. The most r e c e n t p r o j e c t i o n s o f h o u s i n g demand by t h e Economic' C o u n c i l o f Canada a r e c o n t a i n e d i n t h e S i x t h A n n u a l Review (Economic C o u n c i l o f Canada; 1969), w h i c h .have been summarized i n T a b l e 3. These e s t i m a t e s a r e dependent upon the e x p e c t e d r a p i d growth i n new h o u s e h o l d f o r m a t i o n as w e l l as needs g e n e r a t e d from the o t h e r s o u r c e s p r e v i o u s l y o u t l i n e d , and r e p r e s e n t a h i g h r a t e o f growth i n demand. The r a t e o f growth o f e x p e n d i -t u r e s f o r new h o u s i n g i s e x p e c t e d t o a v e r a g e 6.1 p e r c e n t i n t h e 1967-75 p e r i o d ( E c o n o m i c . C o u n c i l o f Canada, 1969). By 1975, t o t a l h o u s i n g e x p e n d i -t u r e s i n Canada would thus be a p p r o x i m a t e l y 4.4 p e r c e n t o f Gross N a t i o n a l P r o d u c t , compared w i t h 3.8 p e r c e n t i n 1966 (Economic C o u n c i l o f Canada, 1967 and 1969). TABLE 3 COMPONENTS OF HOUSING DEMAND BASED ON DEMOGRAPHIC TRENDS (An n u a l A v e r a g e s ) ACTUAL E S T I M A T E D 1961-66 1966-71 1971-76 1976-81 (th o u s a n d s o f u n i t s ) Net F a m i l y F o r m a t i o n 76 111 135 155 U n d o u b l i n g 11 11 8 6 Net Non-Family .Household F o r m a t i o n 37 50 56 60 Net Replacements 10 13 21 26 V a c a n c i e s 6 5 10 10 T o t a l ( A n n u a l Average) 140 190 230 257 ( F i v e Y e a r T o t a l s ) (700) (950) (1150) (1285) So u r c e : • C e n t r a l Mortgage and H o u s i n g C o r p o r a t i o n , 1969a. C a n a d i a n H o u s i n g S t a t i s t i c s 1968. Trends i n Dwelling Types A rapid expansion of house construction w i l l not necessa r i l y alone ensure an increasing market f or wood products. An equally important question i s the form t h i s new construction w i l l take. As a r e s u l t of d i f -f e r i n g b u i l d i n g techniques, s t r u c t u r a l requirements, and b u i l d i n g codes, various.types of dwellings have d i f f e r e n t materials requirements. Gener-a l l y speaking, single-detached houses (using conventional wood, frame con-struction) have the highest, and hi g h - r i s e apartments the lowest consump- • tion of wood products per dwelling unit constructed. Two-family s t r u c -tures are s i m i l a r to single-detached houses i n t h e i r use of materials, while row housing f a l l s between these and apartments.- Consumption data' i n d i c a t i n g the s i g n i f i c a n t differences which e x i s t between these dwelling types w i l l be presented i n the following section. Trends i n dwelling types are•thus an important factor i n determining the volume of wood pro-ducts employed as well as the form i n which they w i l l be needed. Whether the factors which underlie these trends are beyond the control of the fo r e s t i n d u s t r i e s ,or not, a close examination of them i s e s s e n t i a l to a cl e a r understanding of the housing market and i t s future p o t e n t i a l for the wood products i n d u s t r i e s . The Dominion Bureau of S t a t i s t i c s (DBS) and Central Mortgage and Housing Corporation (CMHC) report i d e n t i c a l s t a t i s t i c s for the volume of housing s t a r t s and completions by dwelling types. These data, for a l l areas of Canada, are presented i n Tables 4 and 5 , and i l l u s t r a t e d i n Figures 1 and 2. The single-family dwelling has been d e c l i n i n g i n r e l a t i v e import-ance over the period f o r which s t a t i s t i c s are av a i l a b l e . In 1950, s t a r t s of s i n g l e - d e t a c h e d u n i t s a c c o u n t e d f o r 74.1 p e r c e n t o f a l l h o u s i n g s t a r t s , b u t had d e c l i n e d t o 61.7 p e r i c e n t by 1960, and t o 37.3 p e r cent by 1969. On t h e o t h e r hand, s t a r t s o f apartment u n i t s r o s e from 15.8 p e r c e n t i n 1950 t o 27.3 p e r c e n t i n 1960, and had r e a c h e d 52.7 p e r c e n t o f a l l s t a r t s by 1969. These d a t a i n d i c a t e t h a t t h e t r e n d toward apartment c o n s t r u c t i o n , w h i c h o r i g i n a t e d i n the 1950's, began t o a c c e l e r a t e i n t h e 1960's, T h i s i n c r e a s e i n apart m e n t s and c o r r e s p o n d i n g d e c r e a s e i n s i n g l e - f a m i l y u n i t s i s q u i t e e v i d e n t i n b o t h F i g u r e s 1 and 2. S t a r t s o f s e m i - d e t a c h e d and d u p l e x u n i t s remained r e l a t i v e l y s t a b l e o v e r most of the p e r i o d s i n c e 1950, w i t h a s l i g h t d e c r e a s e e v i d e n t s i n c e 1961. Row h o u s i n g , w h i c h was a l m o s t n o n - e x i s t e n t i n 1950, has g r a d u a l l y i n c r e a s e d t o r e p r e s e n t 5.1 p e r c e n t o f s t a r t s i n 1969. By comparing F i g u r e s 1 and 2, i t i s a p p a r e n t t h a t s t a r t s and c o m p l e t i o n s f o l l o w a s i m i l a r p a t t e r n , t h e main d i f f e r e n c e b e i n g t h a t c o m p l e t i o n s l a g b e h i n d s t a r t s because many u n i t s begun i n a g i v e n y e a r a r e c o m p l e t e d i n t h e f o l l o w i n g y e a r . Between 1950 and 1969, c o m p l e t i o n s of s i n g l e - f a m i l y u n i t s (as a p e r c e n t o f t o t a l c o m p l e t i o n s ) d e c l i n e d from 68.2 t o 40.1 p e r c e n t , w h i l e o v e r the same p e r i o d , t h e p r o p o r t i o n o f apartment u n i t s c o m p l e t e d r o s e from 14.4 t o 50.5 p e r c e n t . STARTS BY TYPE OF DWELLING, ALL AREAS YEAR SINGLE DETACHED SEMI-DETACHED' AND DUPLEX * ROW APARTMENT1" TOTAL (Number o f D w e l l i n g u n i t s ) 1949 71,425 7,536 - 11,548 90,509 1950 68,675 8,664 631 14,561 92,531 1951 53,002 5,658 54 9,865 68,579 1952 60,696 5,360 299 16,891 83,246 1953 70,782 7,202 553 23,872 102,409 1954 78,574 6,498 1,000 27,455 113,527 1955 99,003 10,606 1,909 26,758 138,276 1956 90,620 9,441 2,263 24,987 127,311 1957 82,955 9,272 2,214 27,899 122,340 1958 104,508 10,713 2,457 46,954 164,632 1959 92,178 10,468 1,908- 36,791 141,345 1960 67,171 9,699 2,301 29,68/7 108,858 1961 76,430 11,650 1,864 35,633 125,577 1962 74,443 • 10,975 3,742 40,935 130,095 1963 77,158 7,891 3,895 59,680 148,624 1964 77,079 8,706 4,755. 75,118 165,658 1965 75,441 7,924 5,306 77,894 166,565 1966 70,642 7,281 5,000 51,551 134,474 1967 72,534 9,939 7,392 74,258 164,123 1968 75,339 10,114 8; 942 103,383 196,878 1969 78,404 10,773 10, :721 110,917 210,415 * I n c l u d e s o n l y s i n g l e a t t a c h e d houses i n a row o f t h r e e o r more d w e l l i n g u n i , t s . t I n c l u d e s the f o l l o w i n g : ( i ) d o u b l e - d u p l e x ; ( i i ) t r i -p l e x ; ( i i i ) row-d u p l e x e s ; ( i v ) a p a r t m e n t s as commonly known; and ( v) d w e l l i n g s o v e r , o r at : the back o f a ' s t o r e , o r o t h e r n o n - r e s i d e n t i a l s t r u c t u r e . A d w e l l i n g u n i t i s d e f i n e d as a s t r u c t u r a l l y s e p a r a t e s e t o f l i v i n g q u a r t e r s w i t h p r i v a t e e n t r a n c e from e x t e r i o r - o r common h a l l , l o b b y , v e s t i b u l e , o r s t a i r w a y . i n s i d e the b u i l d i n g . S o u r c e : C e n t r a l Mortgage and H o u s i n g C o r p o r a t i o n , 1969a. C a n a d i a n H o u s i n g S t a t i s t i c s 1968. COMPLETIONS BY TYPE OF DWELLING, ALL AREAS SEMI-YEAR SINGLE DETACHED DETACHED AND DUPLEX * ROW APARTMENT1", TOTAL 1 | (Number o f D w e l l i n g U n i t s ) ) 1949 68,966 7,309 48.5 11,473 88,233 1950 68,685 7,376 145 12,809 89,015 1951 60,366 7,568 585 12,791 -834310 1952 55,967 5,314 99 11,707 73,087 1953 68,916 7,714 37^2 19,837 96,839 1954 . 71,760 6,098 1,065 23,042 101,965 1955 90,553 8,278 1,547 27,551 127,929 1956 95,656 11,872 2,137 26,035 135,700 1957 81,096 8,464 2,350 25,373 117,283 1958 96,830 10,004 2,226 37,626 146,686 1959 95,455 10,923 2,308 36,985 145,671 1960 78,113 9,911 1,616 34,117 123,757 1961 76,171 10,593 2,019 26,825 115,608 1962 75,593 11,922 2,451 36,716 126,682 1963 71,585 7,150 3,487 45,969 128,191 1964 • 76,225 :;8,091 3,861 62,786 150,963 1965 75,104 8,730 4,097 65,106 153,037 1966 73,858 7,707 6,412 74,215 162,192 1967 73,631 9,089 5,431 61,091 149,242 1968 74,640 10,098 7,896 78,359 170,993 1969 78,584 10,483 7,827 98,932 195,826 * I n c l u d e s o n l y s i n g l e a t t a c h e d houses i n a row of t h r e e o r more d w e l l i n g u n i t s . t I n c l u d e s the f o l l o w i n g: ( i ) d o u b l e - d u p l e x ; ( i i ) t r i -p l e x ; ( i i i ) r o w - d u p l e x e s ; ( i v ) apartments as commonly known; and (v ) d w e l l i n g s o v e r , o r a t the back of a s t o r e , o r o t h e r n o n - r e s i d e n t i a l s t r u c t u r e . A d w e l l i n g u n i t i s d e f i n e d as a s t r u c t u r a l l y s e p a r a t e s e t o f l i v i n g q u a r t e r s w i t h p r i v a t e e n t r a n c e from e x t e r i o r o r common h a l l , l o b b y , v e s t i b u l e , o r s t a i r w a y i n s i d e t h e b u i l d i n g . S o u r c e : C e n t r a l .Mortgage and H o u s i n g C o r p o r a t i o n , 1969a. C a n a d i a n H o u s i n g S t a r t i s t i c s 1968. The t r e n d t o apartment c o n s t r u c t i o n w i l l c o n t i n u e , and l e v e l o f f a t some upper l i m i t w h i c h can o n l y be s p e c u l a t e d upon a t the p r e s e n t t i m e . I n b o t h Europe and the U.S.A., a r e c e n t t r e n d toward l o w - r i s e m u l t i - f a m i l y d w e l l i n g s , r a t h e r t h a n h i g h - r i s e , has been n o t e d . T h i s may i n d i c a t e t h a t an i n c r e a s e i n l o w - r i s e a p a r t m e n t s and r.ow houses w i l l a l s o o c c u r i n Canada. F a c t o r s . I n f l u e n c i n g Types of D w e l l i n g s C o n s t r u c t e d To u n d e r s t a n d t h e e v o l v i n g emphasis on apartments and d e c r e a s i n g s i n g l e - f a m i l y u n i t s , i t i s n e c e s s a r y t o i s o l a t e t he f a c t o r s i n f l u e n c i n g t h e t y p e s o f d w e l l i n g s c o n s t r u c t e d and we i g h t h e i r r e l a t i v e i m p o r t a n c e . A l t h o u g h a.few o t h e r s may e x i s t , the f o l l o w i n g a r e p r o b a b l y the most s i g -n i f i c a n t e l ements i n t e r a c t i n g t o produce the t r e n d s n o t e d above: u r b a n p o p u l a t i o n g r o w t h , a v a i l a b i l i t y o f mortgage money, l a n d c o s t s , r e n t a l c o s t s v e r s u s house p r i c e s , p e r s o n a l d i s p o s a b l e and f a m i l y incomes, con-sumer p r e f e r e n c e s , and z o n i n g b y - l a w s . ( i ) . Urban p o p u l a t i o n growth T h i s i s t h e g r e a t e s t s i n g l e element i n f l u e n c i n g the t r e n d toward ' apartment c o n s t r u c t i o n , and i s c l o s e l y l i n k e d w i t h some of t h e o t h e r f a c - . t o r s l i s t e d above. Urban growth i n Canada has been b o t h e x t e n s i v e and s w i f t . About 40 y e a r s ago, u r b a n p o p u l a t i o n became l a r g e r t h a n r u r a l p o p u l a t i o n , and today a p p r o x i m a t e l y t h r e e - q u a r t e r s o f t h e p o p u l a t i o n i s ur b a n ( S m i t h , A.J.R., 1969). I n f a c t , o v e r the p a s t 10 o r 15 y e a r s , the r u r a l p o p u l a t i o n has d e c l i n e d . I t i s a n t i c i p a t e d t h a t by 1980, 80 p e r c e n t o f the p o p u l a t i o n w i l l be l i v i n g i n u r b a n a r e a s (Economic C o u n c i l o f Canada, 1969). There i s p o s s i b l y some upper l i m i t t o the c o n c e n t r a t i o n of u r b a n p o p u l a t i o n b u t , j u d g i n g f r o m t h e e x p e r i e n c e o f o t h e r h i g h l y u r b a n i z e d c o u n t r i e s , t h e r e i s no e v i d e n c e t h a t t h i s l e v e l i s l i k e l y t o be under 80 p e r c e n t (Economic C o u n c i l o f Canada, 1967) . The f a s t e s t g r o w i n g a r e a s a r e t h e l a r g e u r b a n c e n t r e s , p a r t i c u l a r l y M o n t r e a l , T o r o n t o , and V a n c o u v e r , w h i c h c o l l e c t i v e l y a c c o u n t e d f o r o n e - q u a r t e r of t h e p o p u l a -t i o n i n t h e mid-1960's and a r e f o r e c a s t t o c o n t a i n one out o f t h r e e Cana-d i a n s by 1980 ( S m i t h , A.J.R., 1969). These t r e n d s have i m p o r t a n t i m p l i c a -t i o n s f o r h o u s i n g , and w i l l i n f l u e n c e t h e demand f o r wood p r o d u c t s t o the e x t e n t t h a t l o c a t i o n o f h o u s i n g ( u r b a n v e r s u s r u r a l ) i n f l u e n c e s t h e t y p e of d w e l l i n g c o n s t r u c t e d . Apartments a c c o u n t f o r a g r e a t e r p r o p o r t i o n of new h o u s i n g i n u r b a n a r e a s t h a n shown i n F i g u r e s 1 and 2 f o r a l l r e g i o n s and, c o n s e q u e n t l y , s i n g l e - f a m i l y d w e l l i n g s a c c o u n t - f o r a s m a l l e r p r o p o r t i o n of new u r b a n h o u s i n g t h a n i n t h e c o u n t r y a s . a w h o l e . Based on CMHC d a t a , i n 1969 s t a r t s o f d e t a c h e d houses a c c o u n t e d f o r 37.3 p e r c e n t of a l l s t a r t s i n Canada, b u t o n l y 27.6 p e r c e n t o f s t a r t s i n u r b a n a r e a s . I n t h e same y e a r , a p a r t m e n t s composed 52.7 p e r c e n t o f a l l s t a r t s i n Canada, and 61.6 p e r c e n t o f s t a r t s i n u r b a n a r e a s . I t may a l s o be n o t e d t h a t i n 1969, 94.3 p e r c e n t o f a l l apartment s t a r t s were i n u r b a n a r e a s , w h i l e o n l y 60.0 p e r c e n t of s t a r t s of d e t a c h e d houses a r e i n t h e s e a r e a s . These l a t t e r p r o p o r t i o n s have been r e l a t i v e l y c o n s t a n t o v e r t h e p a s t s e v e n y e a r s . Be-tween 1962 and 1969, a c c o r d i n g t o the same s o u r c e , t o t a l s t a r t s i n u r b a n C e n t r e s of 10,000 p o p u l a t i o n o r more. -a r e a s has i n c r e a s e d f r o m 78.4 p e r c e n t t o 80.7 p e r c e n t o f t o t a l s t a r t s i n Canada. The Economic C o u n c i l o f Canada i n d i c a t e d i n i t s 1967 a n n u a l r e v i e w t h a t p o s s i b l y 98 p e r c e n t of r e s i d e n t i a l c o n s t r u c t i o n w i l l be u r b a n by the l a t e 1970's. T h i s would s u g g e s t a c o n s i d e r a b l y h i g h e r r e l a - . t i v e c o n s t r u c t i o n of apartments t h a n a t t h e p r e s e n t t i m e . ( i i ) Consumer p r e f e r e n c e s C l o s e l y a s s o c i a t e d w i t h t h e i n c r e a s i n g u r b a n p o p u l a t i o n a r e t h e h o u s i n g p r e f e r e n c e s o f t h e v a r i o u s groups o f w h i c h i t i s composed. I t has been i n d i c a t e d above t h a t a h i g h r a t e o f new f a m i l y f o r m a t i o n i s ex-p e c t e d t o c o n t i n u e t o 1980. Young f a m i l y h o u s e h o l d heads (who w i l l be p r e d o m i n a n t among new f a m i l y h o u s e h o l d heads) w i l l a c c e n t u a t e the, demand f o r r e n t a l accommodation f o r income and o t h e r r e a s o n s ( I l l i n g , 1 9 6 4 ) . N o n - f a m i l y h o u s e h o l d s , w h i c h are.composed p r i m a r i l y of f e m a l e s (and t o some e x t e n t m a l e s ) i n o l d e r age g r o u p s , and by y o u n g . a d u l t s , w i l l a l s o be p r o v i d i n g c o n s i d e r a b l e demand f o r h o u s i n g t o 1980 (Economic C o u n c i l of Canada, 1 9 6 7 ) . The p r e f e r e n c e . o f t h e s e g r o u p s , p a r t i c u l a r l y t h e young-e r n o n - f a m i l y h o u s e h o l d heads, i s l a r g e l y f o r r e n t a l s ( I l l i n g , 1964) . H i g h m o b i l i t y o f t h e p o p u l a t i o n ( w h i c h i s f r e q u e n t l y a s s o c i a t e d w i t h h i g h e r e d u c a t i o n a l l e v e l s ) w i l l a l s o t e n d t o i n c r e a s e the demand f o r r e n t a l s ( D a v i s , 1 9 67). A l t h o u g h d i f f i c u l t t o q u a n t i f y , I l l i n g (1964) has s u g g e s t e d t h a t the t r e n d t o apartment l i v i n g may a l s o r e f l e c t a d i s e n c h a n t -ment w i t h l i f e i n the s u b u r b s , g r e a t e r a v a i l a b i l i t y o f a t t r a c t i v e apartment s p a c e , and t r o u b l e s o m e commuting p r o b l e m s . On t h e o t h e r hand, no one d w e l l i n g t y p e would l i k e l y s u i t e v e r y house-h o l d a t e v e r y s t a g e of l i f e and, a c c o r d i n g l y , t h e r e s h o u l d be.a v a r i e t y of d w e l l i n g t y p e s t o c o r r e s p o n d t o t h e v a r i e t y i n h o u s e h o l d s ( R o y a l A r c h i -t e c t u r a l I n s t i t u t e o f Canada, 1960) . I n Canada, i t has been t r a d i t i o n a l f o r f a m i l i e s t o own t h e i r own home and t h e s o c i a l v a l u e o f l a n d , o w n e r -s h i p i s h i g h ( R a s h l e i g h , 1 9 6 2 ) . Adamson (1967) and Mansur (1967) f e e l t h a t t h e t r e n d t o apartment l i v i n g does n o t s p e l l t he doom of t h e s i n g l e -f a m i l y d w e l l i n g and t h a t , i n t h e l o n g t e r m , t h e r e w i l l be a need f o r a l a r g e r p r o p o r t i o n o f t h e h o u s i n g s t o c k i n t h e form o f d e t a c h e d h o u s e s . Most new r e n t a l s have been d e s i g n e d f o r s m a l l f a m i l y o r n o n - f a m i l y groups (Rose, 1967) and do n o t meet the needs of f a m i l y l i v i n g o t h e r t h a n w e l l - s e r v i c e d p h y s i c a l s h e l t e r ( E r i c k s o n , 1 9 6 7 ) . I t was found by t h e r e c e n t Task F o r c e on H o u s i n g and Urban Development t h a t the o v e r a l l p r e -f e r e n c e i s " f o r s i n g l e - f a m i l y h o u s e s . U s i n g i n f o r m a l (and n o n - s c i e n t i f i c ) s a m p l i n g t e c h n i q u e s , i t was found t h a t a t l e a s t 80 p e r c e n t o f t h o s e p r e -s e n t a t t h e i r p u b l i c m e e t i n g s wanted t o own t h e i r own home, a f i g u r e w h i c h i s r e p o r t e d t o c o r r e s p o n d w i t h the f i n d i n g s o f a T o r o n t o p r o f e s s o r u s i n g more s c i e n t i f i c s a m p l i n g p r o c e d u r e s ( H e l l y e r , 1 9 6 9 ) . ( i i i ) I n v e s t o r p r e f e r e n c e s The r e s i d e n t i a l c o n s t r u c t i o n i n d u s t r y , b e i n g composed l a r g e l y . o f numerous s m a l l companies, depends h e a v i l y on borrowed funds f o r i t s c o n -s t r u c t i o n a c t i v i t i e s ( P o r t e r , 1964); a p p r o x i m a t e l y 82 p e r c e n t o f the f i n a n c i n g was from e x t e r n a l s o u r c e s f r o m 1954 t o 1964. T h e ? . p o t e n t i a l i n -f l u e n c e , of e x t e r n a l i n v e s t o r s on t y p e s o f d w e l l i n g s c o n s t r u c t e d i s thus w o r t h c o n s i d e r i n g . The m a j o r i t y of mortgage l o a n s made i n Canada f a l l under one of t h r e e c a t e g o r i e s : ( i ) NHA i n s u r e d l o a n s by l e n d i n g i n s t i t u t i o n s ( l i f e i n s u r a n c e companies, t r u s t companies, mortgage l o a n companies, c h a r t e r e d b a n k s , e t c . ) ; ( i i ) c o n v e n t i o n a l l o a n s by l e n d i n g i n s t i t u t i o n s ; ( i i i ) NHA i n s u r e d l o a n s by CMHC. I n 1968, t h e number o f d w e l l i n g u n i t s approved under each o f t h e s e was: ( i ) N H A - i n sured l o a n s (by i n s t i t u t i o n s ) 61,601 ( i i ) j c o n v e n t i o n a l l o a n s 86,036 ( i i i ) CMHC l o a n s 27,487 The t y p e s . o f l o a n s made by CMHC a r e summarized i n T a b l e 6. I t i s e v i d e n t t h a t t h e m a j o r i t y o f . d i r e c t l o a n s made under S e c t i o n 40 o f t h e N a t i o n a l H o u s i n g A c t have been t o i n d i v i d u a l s f o r t h e p u r c h a s e s o f new ho u s e s . The " o t h e r " c a t e g o r y , w h i c h has been i n c r e a s i n g r a p i d l y i n t h e p a s t few y e a r s , c o n s i s t s l a r g e l y o f l o w - r i s e m u l t i - u n i t d w e l l i n g s . A l t h o u g h CMHC mortgages have been l a r g e l y f o r s i n g l e - f a m i l y . d w e l l i n g s i n t h e 1960's,. i n 1968 they-were d i v i d e d f a i r l y e v e n l y between s i n g l e and m u l t i p l e u n i t s . I n s t i t u t i o n a l l e n d e r s a c c o u n t f o r by f a r t h e l a r g e s t p o r t i o n o f mortgages a p p r o v e d , and a r e t h u s . i n t h e b e s t p o s i t i o n t o i n f l u e n c e t h e t y p e o f d w e l l i n g u n i t s c o n s t r u c t e d . I n T a b l e 7 i s i n d i c a t e d t h e r e l a t i v e d i s -p o s i t i o n o f i n s t i t u t i o n a l mortgage f u n d s between new s i n g l e . d e t a c h e d houses and m u l t i p l e u n i t . h o u s i n g f o r c o n v e n t i o n a l and NHA-insured l o a n s . I n t h e 1950's, t h e N a t i o n a l H o u s i n g A c t s t i m u l a t e d t h e c o n s t r u c t i o n of d e t a c h e d d w e l l i n g s n o t e x c e e d i n g a s p e c i f i c s i z e and v a l u e ( I l l i n g , 1 964). A t l e a s t s i n c e 1957, t h e r e has been a d e f i n i t e t r e n d toward t h e f i n a n c i n g o f m u l t i p l e - u n i t d w e l l i n g s under NHA-insured l o a n s . I t i s a l s o a p p a r e n t from T a b l e 7 t h a t t h e m a j o r i t y o f c o n v e n t i o n a l mortgage funds p r o v i d e d by i n s t i -t u t i o n a l l e n d e r s have been f o r m u l t i p l e — u n i t r e s i d e n c e s , a l t h o u g h no maj o r t r e n d i s a p p a r e n t . NHA-APPROVED LOANS BY,CMHC FOR NEW HOUSING SECTION 40, NHA YEAR HOME-OWNERSHIP RENTAL ( D w e l l i n g U n i t s ) OTHER* . TOTAL 1962 13,223 1,328 14,551 1963 21,953 562 2,094 24,609 1964 25,254 1,566 1,861 28,681 1965 27,465 2,328 2,521 32,314 1966 27,844 2,828 5,403 36,075 1967 28,185 4,947 '9,912 43,044 19.68 12,992 1,352 13,143 27,487 I n c l u d e s a c t i v i t y under the f o l l o w i n g s e c t i o n s o f the N a t i o n a l H o u s i n g A c t : L i m i t e d D i v i d e n d (Sec. 1 6 ) , Non-p r o f i t ( Sec. 16A), P r i m a r y I n d u s t r y (Sec. 1 7 ) , P u b l i c Hous-i n g (Sec. 35D), St u d e n t H o u s i n g ( S e c , 36B). Sour c e : C e n t r a l Mortgage and H o u s i n g C o r p o r a t i o n , 1969a. C a n a d i a n H o u s i n g S t a t i s t i c s •: 1968. MORTGAGE LOANS APPROVED BY LENDING INSTITUTIONS, .BY .TYPE OF DWELLING NHA—Insured- C o n v e n t i o n a l YEAR SINGLE DETACHED DWELLINGS MULTIPLE DWELLINGS SINGLE DETACHED DWELLINGS (Per Cent o f D w e l l i n g U n i t s ) MULTIPLE DWELLINGS 1957 1958 1959 1960 1961 1962 1963 1964 1965 1966 1967 1968 92.5 82.6 85.7 67.0 62.2 69.4 65.4 43.4 33.5 29.2 22.0 32.8 7.5 17.4 14.3 33.0 37.8 30.6 34.6 56.6 66.5 70.8 78.0 67.2 37.1 27.4 30.0 34.1 32.6 24.9 24.1 21.8 24.7 30.1' 26.5 27.1 62.9 72.6 70.0 65.9 67.4 75.1 75.9 78.2 75.3 69.9 73.5 72.9 So u r c e : C e n t r a l - Mortgage and H o u s i n g C o r p o r a t i o n , 1969a. C a n a d i a n H o u s i n g S t a t i s t i c s 1968. The c h a r t e r e d b a n k s , w h i c h v i r t u a l l y w i t h d r e w from NHA l e n d i n g i n 1959, resumed mortgage l e n d i n g i n May, 1967. The banks f a v o u r s i n g l e -f a m i l y u n i t s as r e c i p i e n t s of t h e i r mortgage f u n d s , p a r t l y b e c a u s e l i t e n a b l e s them t o s p r e a d funds more e f f e c t i v e l y a c r o s s t h e w h ole c o u n t r y t h r o u g h e x t e n s i v e bank n e t w o r k s (CMHC, 1969a) , and p a r t l y b e c a u s e of t h e s h o r t - t e r m t u r n - o v e r . of t h e s e mortgages v e r s u s mortgages on apartments ( M a t h i a s , 1968). The c h a r t e r e d banks ( w h i c h a c c o u n t e d f o r 18.5 p e r c e n t of mortgage l o a n s approved by l e n d i n g i n s t i t u t i o n s i n 1968) .can be e x -p e c t e d t o i n c r e a s e t h e i r mortgage p a r t i c i p a t i o n ( S m i t h , L.B., 1969) and t h u s e n s u r e t h e a v a i l a b i l i t y of funds f o r d e t a c h e d h o u s e s . On t h e o t h e r hand, l i f e i n s u r a n c e companies ( t h e l a r g e s t group o f i n s t i t u t i o n a l l e n d e r s ) a r e showing an i n c r e a s i n g p r e f e r e n c e f o r mortgages on r e n t a l , p r o j e c t s ( M a t h i a s , 1 9 6 8 ) . One r e a s o n f o r t h i s i s t h a t i n a r e n t a l p r o j e c t , t h e y can l o c k a b o r r o w e r i n t o t h e mortgage f o r a r e l a t i v e -l y l o n g p e r i o d (which i s n e g o t i a b l e , and o f t e n . 2 5 y e a r s o r more) compared t o f i v e y e a r s f o r c o n v e n t i o n a l and N H A - i n s u r e d l o a n s t o home owners. Thus, when i n t e r e s t r a t e s a r e h i g h , r e n t a l p r o j e c t s a r e favoured. ( M a t h i a s , 1968). A second r e a s o n f o r p r e f e r r i n g mortgages o n . r e n t a l p r o j e c t s i s t h e p o s s i b i l -i t y o f e q u i t y p a r t i c i p a t i o n w h i c h p r o v i d e s a hedge a g a i n s t i n f l a t i o n . Such p a r t i c i p a t i o n cannot be o b t a i n e d i n the c a s e of i n d i v i d u a l homes (Boyd, 1968). A n o t h e r r e a s o n f o r more money g o i n g i n t o a partments i s t h e l o w e r c o s t o f s e r v i c i n g the mortgage, a c o s t w h i c h i s r e p o r t e d l y t h r e e t i m e s h i g h e r f o r s i n g l e - f a m i l y u n i t s t h a n f o r apartments ( G i b s o n , 1969). O t h e r NHA-approved l e n d e r s ( t r u s t companies, l o a n companies, e t c . ) a l s o f a v o u r r e n t a l p r o j e c t s f o r t h e i r funds f o r t h e r e a s o n s i n d i c a t e d above. P e n s i o n f u n d s , w h i c h a r e now b e g i n n i n g t o i n c r e a s e t h e i r commitment t o m ortgages, appear .to be f o l l o w i n g the l e a d o f l i f e i n s u r a n c e companies i n demanding e q u i t y p a r t i c i p a t i o n ( G i b s o n , 1969). A t p r e s e n t , w i t h the h i g h e s t p r o -p o r t i o n o f i n s t i t u t i o n a l mortgage funds coming from l i f e i n s u r a n c e , t r u s t , l o a n , and o t h e r such companies ( a p p r o x i m a t e l y 80 p e r c e n t ) i n s t i t u t i o n a l i n v e s t o r p r e f e r e n c e s a r e d e f i n i t e l y b a l a n c e d i n f a v o u r o f m u l t i p l e u n i t s t r u c t u r e s . ( i v ) Land c o s t s The c o s t o f l a n d , as i t i n f l u e n c e s t h e b u i l d i n g o f a p a r t m e n t s , o n l y o p e r a t e s i n urban a r e a s . I f l a n d p r i c e s become too h i g h , i t becomes u n e c o n o m i c a l t o b u i l d d e t a c h e d h o u s e s , the l a n d r e q u i r i n g more i n t e n s i v e use s u c h as f o r a p a r t m e n t s . W i t h the h i g h degree o f u r b a n i z a t i o n e x p e c t e d , as p r e v i o u s l y o u t l i n e d , i n c r e a s i n g p r e s s u r e s on urban l a n d can be a n t i c i -p a t e d . T h i s w i l l l o g i c a l l y l e a d t o more i n t e n s i v e use and h i g h e r c o s t s of l a n d i n u r b a n a r e a s , w i t h t h e r e s u l t t h a t m u l t i p l e u n i t d w e l l i n g s w i l l be f a v o u r e d . I t s h o u l d be r e c o g n i z e d t h a t the a l l o c a t i o n o f l a n d t o a p a r t -ment c o n s t r u c t i o n i s l a r g e l y a z o n i n g m a t t e r , hence h i g h l a n d c o s t s a l o n e a r e n o t a s u f f i c i e n t b a s i s on w h i c h t o f o r e c a s t i n c r e a s e s i n m u l t i - f a m i l y d w e l l i n g s . • (v) Incomes and h o u s i n g c o s t s The r e l a t i v e c o s t o f v a r i o u s t y p e s o f accommodation, combined w i t h a b i l i t y t o pay, t o g e t h e r i n f l u e n c e a f a m i l y ' s c h o i c e o f r e s i d e n c e . I n c r e a s e s i n h o u s i n g c o s t s can be a t t r i b u t e d t o a number o f f a c t o r s . H e l l y e r (1969) i n d i c a t e d t h a t t h e t h r e e major causes a r e : ( i ) t h e c o s t o f money; ( i i ) the c o s t o f l a n d ; and ( i i i ) s a l e s t a x on b u i l d i n g m a t e r i a l s . The i n c r e a s e i n l a n d c o s t s i s l a r g e l y due t o demands from- m u n i c i p a l i t i e s t h a t d e v e l o p e r s i n s t a l l a v a r i e t y o f f u l l y - p a i d s e r v i c e s i n new sub-d i v i s i o n s ( A n d r a s , 1969). M u n i c i p a l z o n i n g laws have been c i t e d by t h e R o y a l A r c h i t e c t u r a l I n s t i t u t e o f Canada (1960) t o be r e s p o n s i b l e f o r t h e w a s t e o f s u b s t a n t i a l p o r t i o n s o f suburban l a n d , t h u s r a i s i n g t h e c o s t p e r i n d i v i d u a l l o t . I n r e c e n t y e a r s , i n t e r e s t r a t e s on mortgages have c l i m b e d s t e e p l y . A c c o r d i n g t o H e l l y e r ( 1 9 6 9 ) , a r i s e o f one p e r c e n t a g e p o i n t i n i n t e r e s t r a t e s on a $15,000 25-year mortgage i n c r e a s e s t h e m o n t h l y pay-ment by o v e r $9, r a i s i n g i t s t o t a l a m o r t i z a t i o n c o s t by more t h a n $2,800. I n a d d i t i o n t o t h e s e r e a s o n s , p r i c e i n c r e a s e s can be t r a c e d t o l a r g e r f l o o r a r e a s , and m ounting quotas of m e c h a n i c a l gear and c o n v e n i e n c e s b u i l t i n d u r i n g c o n s t r u c t i o n . I n s p i t e of r a p i d i n c r e a s e s i n s h e l t e r c o s t s , incomes have been r i s i n g e v e n , f a s t e r (Adamson, 1967). E v i d e n c e o f t h i s i s shown i n F i g u r e 3, where i t i s a p p a r e n t t h a t p e r s o n a l d i s p o s a b l e income p e r c a p i t a has been r i s i n g f a s t e r t h a n h o u s i n g c o s t s . A l t h o u g h f a m i l y incomes may be a b e t t e r measure t o use t h a n p e r s o n a l d i s p o s a b l e income p e r c a p i t a , such d a t a a r e somewhat i n c o m p l e t e . F i g u r e s p r e s e n t e d by CMHC (1969a) f o r a v a i l a b l e y e a r s i n d i c a t e t h a t f a m i l y incomes are r i s i n g a t an even h i g h e r r a t e t h a n p e r s o n a l d i s p o s a b l e income p e r c a p i t a . Assuming t h a t the d i s t r i b u t i o n of incomes i s n o t becoming l e s s e q u i t a b l e t h r o u g h o u t Canada, the a b i l i t y o f Canadians to p u r c h a s e h o u s i n g i s thus i n c r e a s i n g . A t the same t i m e , t h e i n c r e a s i n g v o l -ume o f goods and s e r v i c e s a v a i l a b l e to t h e consumer may be d e c r e a s i n g t h e p r o p o r t i o n of h i s income w h i c h i s w i l l i n g t o a l l o c a t e t o h o u s i n g . I n s u p p o r t o o o o -O. £ z x T3 C 220 200 -1 8 0 -1 6 0 140 _ Personal disposable income per capita Shelter cost (consumer price index) / - / / / / 1956 1960 1964 1968 Year Figure 3. Indexes of shelter cost and persona) disposable income per capita Source: C M H C , 1969a/ Canadian Housing Statistics 1968. of t h i s , R i c h (1970) i n d i c a t e d t h a t , i n r e c e n t y e a r s , a g r e a t e r . p o r t i o n of the consumer's d i s c r e t i o n a r y p u r c h a s e s has been f o r t r a v e l , s p o r t j r e c r e a t i o n , e d u c a t i o n , and a v a r i e t y o f o t h e r s e r v i c e s . S i n c e 1960, t h e c o s t o f home-ownership has been i n c r e a s i n g a t a f a s t e r r a t e t h a n t h e c o s t o f r e n t a l accommodation. T h i s i s i l l u s t r a t e d i n F i g u r e 4. A l t h o u g h t h e e x t e n t t o w h i c h t h i s has been i n f l u e n c i n g t h e t r e n d t o apartment l i v i n g w ould be d i f f i c u l t t o d e t e r m i n e , i t has un-, d o u b t e d l y been an u n d e r l y i n g f a c t o r . A s s o c i a t e d w i t h t h i s r e l a t i v e l y h i g h e r c o s t o f d e t a c h e d houses (and t h e t r e n d toward apartment l i v i n g ) i s t h e i n c r e a s i n g down payment r e q u i r e m e n t w h i c h o f t e n a c t s as a d e t e r r e n t t o home-ownership (Mansur, 1967) . Under t h e N a t i o n a l H o u s i n g A c t i t i s p o s s i b l e t o o b t a i n a m o r t -gage w i t h a f i v e p e r c e n t down payment. C o n v e n t i o n a l l e n d e r s a r e t h e o r e -t i c a l l y l i m i t e d t o a 75 p e r c e n t l o a n , b u t i n p r a c t i c e i t i s p o s s i b l e t o i n c r e a s e t h i s t o 90 p e r c e n t ( H e l l y e r , 1 9 6 9 ) . The NHA l o a n c e i l i n g (which was $18,000 and j u s t r e c e n t l y r a i s e d t o $25,000), c o u p l e d w i t h i n c r e a s i n g market p r i c e s , have o f t e n r e s u l t e d i n an e v e n . h i g h e r down payment. The aver a g e down payment f o r houses under NHA terms i n c r e a s e d f r o m $2,475 i n 1961 t o $4,547 i n 1968 (CMHC, 1969a) , an i n c r e a s e o f 84 p e r c e n t as com-p a r e d t o a 70 p e r c e n t i n c r e a s e i n f a m i l y incomes o v e r t h e same p e r i o d . The down payment p r o b a b l y has the g r e a t e s t e f f e c t i n d e t e r r i n g new (young) f a m i l i e s from p u r c h a s i n g a house. I t i s a l m o s t i m p o s s i b l e t o i n d i c a t e t h e r e l a t i v e i n f l u e n c e t h e f a c t o r s d i s c u s s e d above have had on the t r e n d towards apartment c o n s t r u c -t i o n . The growth o f urban c e n t r e s has been s i n g l e d out as the most im p o r -t a n t , y e t some of t h e o t h e r f a c t o r s a r e c l o s e l y r e l a t e d t o t h i s phenomenon; O O c -t r> CD CQ c o >o o >o Q n Q 3 Q Q . Q ' X o c (/> 3 CQ co Q n CD 3 o_ CD X CD n O ° 3 in X Q Index Number (1949=100) Cn o o 4^  O o o CO o ro o o \ \ \ \ o o -< CD Q \ \ \ \ TO x CD o 5. 3 Q_ CD O 3 CD -t 3 " T3 00 -. S3 o> 4^  O 3 CD I O 3 CD o CO \ oe and a l l the a s p e c t s o u t l i n e d u n d o u b t e d l y had a s i g n i f i c a n t e f f e c t . L o o k i n g o v e r t h e l i s t o f i t e m s i n v o l v e d i n the i n c r e a s i n g p r o -p o r t i o n o f apartment c o n s t r u c t i o n , i t i s e v i d e n t t h a t they a r e a l l v i r -t u a l l y beyond t h e i n f l u e n c e of the f o r e s t i n d u s t r i e s , w i t h t h e p o s s i b l e e x c e p t i o n o f house p r i c e s . House p r i c e s can o n l y be , i n f l u e n c e d by t h e f o r e s t i n d u s t r i e s t h r o u g h d e c r e a s e s i n t h e i r p r o d u c t c o s t s t o t h e b u i l d e r o r t h r o u g h i n c r e a s e d i n d u s t r i a l i z a t i o n of wood frame c o n s t r u c t i o n methods. V i e w i n g the h i s t o r i c a l upward t r e n d s 3 i n lumber p r i c e s , t h e r e must be some doubt t h a t s i g n i f i c a n t economies can be e f f e c t e d . Even g i v e n such c o s t r e d u c t i o n s , i t i s u n l i k e l y t h a t the demand would be s u f f i c i e n t l y e l a s t i c t o r e s u l t i n i n c r e a s e d p r o f i t s , due t o t h e i n f l u e n c e o f t h e o t h e r f a c t o r s w h i c h have a f f e c t e d t h e t r e n d s t o m u l t i - f a m i l y d w e l l i n g s . I t can be con-c l u d e d t h a t the t r e n d s n o t e d must be a c c e p t e d as g i v e n . E f f o r t s by the f o r e s t i n d u s t r i e s t o improve t h e i r p o s i t i o n i n t h e h o u s i n g m a rkets must be s u p e r i m p o s e d u p o n , t h i s framework o f d w e l l i n g s t y p e s . CONSUMPTION OF WOOD PRODUCTS IN HOUSING I n t h e p r e v i o u s s e c t i o n , t r e n d s i n d w e l l i n g s t y p e s were o u t l i n e d . T h e i r s i g n i f i c a n c e l i e s i n t h e e f f e c t t h a t t y p e o f d w e l l i n g has on wood co n s u m p t i o n . There i s l i t t l e s t a t i s t i c a l i n f o r m a t i o n on t h i s f o r Cana-d i a n h o u s i n g , b u t some g e n e r a l o b s e r v a t i o n s and A m e r i c a n s t a t i s t i c s a r e somewhat e n l i g h t e n i n g . I n t h e p a s t , t h e b u l k o f C a n a d i a n h o u s i n g was o f .the s i n g l e - f a m i l y v a r i e t y , and has t r a d i t i o n a l l y been of wood frame c o n s t r u c t i o n , w i t h r e -s u l t a n t h i g h demands f o r s o f t w o o d lumber and o t h e r wood p r o d u c t s (McCance, 1969a). A c c o r d i n g t o t h e C a n a d i a n Department o f Trade and Commerce ( c a . 19 6 5 ) , about 90 p e r c e n t o f C a n a d i a n houses use wood frame c o n s t r u c t i o n . More r e c e n t l y , o t h e r forms o f low h o u s i n g have d e v e l o p e d , i n c l u d i n g s e m i -d e t a c h e d , d u p l e x , and row or townhouse d w e l l i n g s . The use of wood i s a l s o h i g h i n t h e s e d w e l l i n g t y p e s s i n c e t h e y l a r g e l y f o l l o w wood frame c o n s t r u c t i o n methods, w i t h t h e e x c e p t i o n o f f i r e - r e s i s t i n g p a r t y w a l l s where r e q u i r e d i n b u i l d i n g codes (McCance, 1969a). I t may be n o t e d t h a t the a b s o l u t e volume of wood p e r u n i t used i n wood frame row h o u s i n g would be l e s s t h a n i n a wood frame s i n g l e -f a m i l y house due t o t h e e l i m i n a t i o n o f some w a l l s . S i m i l a r l y , t h e r e a r e s i g n i f i c a n t r e d u c t i o n s i n r o o f i n g m a t e r i a l s r e q u i r e d i n l o w - r i s e d w e l l i n g forms w h i c h have one d w e l l i n g u n i t above a n o t h e r . These o b s e r v a t i o n s a p p l y t o l o w - r i s e a partments of wood frame c o n s t r u c t i o n w h i c h a r e c o n s t r u c -t e d up t o t h r e e s t o r e y s h i g h . Prestemon (1970b) i n d i c a t e d t h a t l o w - r i s e "garden a p a r t m e n t s " o f one t o t h r e e s t o r e y s have t r a d i t i o n a l l y been o f t h e wood frame t y p e i n t h e U.S.A. I t i s r e a s o n a b l e t o assume t h a t t h i s i s a l s o t h e c a s e i n Canada. H i g h - r i s e apartments use s u b s t a n t i a l l y l e s s wood t h a n low h o u s i n g forms ( i n c l u d i n g l o w - r i s e a p a r t m e n t s ) , b o t h b e -cause o f the t h r e a t o f f i r e s p r e a d and f o r s t r u c t u r a l r e a s o n s (McCance, 1969a). There i s no d i s t i n c t i o n made i n CMHC d a t a between l o w - r i s e and . h i g h - r i s e a p a r t m e n t s . The U.S. Department o f A g r i c u l t u r e (1965) has i n -d i c a t e d t h a t l o w - r i s e apartments o f l e s s t h a n f o u r s t o r e y s have a c c o u n t e d f o r o v e r 75 p e r c e n t o f a l l m u l t i - f a m i l y d w e l l i n g u n i t s b u i l t i n the U.S.A. i n r e c e n t y e a r s , and Prestemon (1970b) s t a t e d t h a t about 80 p e r c e n t o f apartments b u i l t i n 1968 were i n t h i s c a t e g o r y . I f t h i s l a t t e r f i g u r e i s a p p l i e d t o t h e 1968 s t a r t s and comple-t i o n s o f apartments i n Canada ( f r o m T a b l e s 4 and 5 ) , an e s t i m a t e d 20,677 s t a r t s and 15,672 c o m p l e t i o n s were i n h i g h - r i s e a p a r t m e n t s , c o r r e s p o n d i n g t o 11 and n i n e p e r c e n t of t o t a l s t a r t s and c o m p l e t i o n s , r e s p e c t i v e l y . I f 90 p e r c e n t of a l l o t h e r forms o f h o u s i n g a r e assumed t o be o f wood frame c o n s t r u c t i o n (as i s t h e case f o r s i n g l e - f a m i l y h o u s e s ) , t h e n a p p r o x i m a t e l y 158,580 s t a r t s , and 139,790 c o m p l e t i o n s i n 1968, c o r r e s p o n d i n g t o 81 and 82 p e r c e n t o f a l l s t a r t s and c o m p l e t i o n s , r e s p e c t i v e l y , were i n d w e l l i n g s u t i l i z i n g wood frame c o n s t r u c t i o n methods. T h i s i s a g r o s s (and perhaps l i b e r a l ) e s t i m a t e b a s e d on two a s s u m p t i o n s , t h e v a l i d i t y o f w h i c h can n e i t h e r be p r o v e n n o r d i s p r o v e n on the b a s i s o f a v a i l a b l e i n f o r m a t i o n . N e v e r t h e l e s s , t h i s e s t i m a t e does i n d i c a t e t h a t the s i t u a t i o n i s n o t as d e p r e s s i n g f o r t h e f o r e s t i n d u s t r i e s as m i g h t be assumed f r o m F i g u r e s 1 and 2. A c t u a l volumes o f wood consumed by t y p e o f d w e l l i n g a r e n o t a v a i l a b l e f o r Canada. Some A m e r i c a n s t u d i e s do p r o v i d e i n s i g h t i n t o t h i s • q u e s t i o n , b u t t h e i r a p p l i c a t i o n t o the Ca n a d i a n s i t u a t i o n i s n o t e n t i r e l y v a l i d . The most t h o r o u g h s t u d y t o d a t e , c a r r i e d o ut by t h e U.S. F o r e s t S e r v i c e , r e p o r t s wood consumption i n s i n g l e - f a m i l y d w e l l i n g s i n s p e c t e d by the F e d e r a l H o u s i n g A d m i n i s t r a t i o n i n 1959, 1962 and 1968 ( P h e l p s , 1970). Some o f t h e f i n d i n g s o f t h i s s t u d y , c o v e r i n g the whole o f t h e U.S.A., a r e s h o w n J i h v T a b l e 8. I n t h e houses sampled, i t was found t h a t , between 1962 and 1968, average lumber c o n s u m p t i o n d e c r e a s e d f r o m 10,701 bd. f t . t o 10,271 bd. f t . T h i s was l a r g e l y a t t r i b u t e d t o t h e r e p l a c e m e n t o f lumber by plywood f o r r o o f s h e a t h i n g , by c a r p e t i n g i n f i n i s h f l o o r i n g , and by plywood and non-wood m a t e r i a l s i n s i d i n g . The use of plywood p e r house, as i n d i c a t e d by t h i s s t u d y , i n -c r e a s e d f r o m 2,382 s q . f t . i n 1962 t o 4,158 s q . f t . i n 1968. T h i s was a t t r i b u t e d l a r g e l y t o i n c r e a s e d plywood consumption f o r s u b f l o o r i n g and u n d e r l a y m e n t , m i l l w o r k and t r i m , and i n r o o f s h e a t h i n g . The i n c r e a s e d c o n s u m p t i o n o f h a r d b o a r d p e r ho u s e , from 507 s q . f t . i n 1962 t o 1,062 s q . f t . i n 1968, was due t o t h e i n c r e a s e d use o f t h i s m a t e r i a l i n s i d i n g and i n m i l l w o r k and t r i m . The use of i n s u l a t i o n b o a r d p e r house remained r e l a t i v e l y c o n s t a n t t h r o u g h o u t t h e p e r i o d , d e c r e a s i n g s l i g h t l y from 750 s q . f t . i n 1962 t o 742 s q . f t . i n 1968. Most of t h e i n c r e a s e d use of p a r t i c l e b o a r d p e r house, from 70 s q . f t . t o 180 s q . f t . o v e r t h e same p e r i o d , was due t o t h e g r e a t e r use of t h i s m a t e r i a l as u n d e r l a y m e n t . I n -c r e a s e d s h i n g l e c onsumption p e r house, from 3.0 t o 3.7 s q u a r e s , r e f l e c t e d a h i g h e r p e r c e n t a g e o f houses u s i n g wood s h i n g l e r o o f s (18 p e r c e n t i n 1968 compared t o 10 p e r c e n t i n 1962). A number of c o n s t r u c t i o n c h a r a c t e r i s t i c s , n o t a b l y f l o o r a r e a , t y p e o f foundation,:,mumber of storeys,:*;, and t y p e of e x t e r i o r w a l l c o n s t r u c t i o n , i n f l u e n c e t h e wood consumption p e r house. The number of s t o r e y s i n f l u e n c e d wood consumption p r i m a r i l y t h r o u g h d i f f e r e n c e s i n f l o o r a r e a . O n e - s t o r e y houses (79 p e r c e n t of t h e 1968 s a m p l e ) , had an average a r e a o f 1,318 s q . f t . , , , s p l i t l e v e l s ( n i n e p e r c e n t of t h e 1968 sample) had an a v e r a g e a r e a o f 1,490 s q . f t . , and 1-1/2 t o t w o - s t o r e y houses a v e r a g e d 1,812 s q . f t . o f ' f l o o r a r e a . The o v e r a l l a v e r a g e f l o o r a r e a was 1,392 s q . f t . T h i s compares t o an a v e r a g e f l o o r a r e a of 1,112 s q . f t . f o r houses f i n a n c e d under t h e N a t i o n a l H o u s i n g A c t i n Canada i n 1968. Hence, one m ight ex-p e c t t h a t l e s s wood.was consumed i n C a n a d i a n houses t h a n shown i n T a b l e 8. Ons t h e o t h e r hand, 43 p e r cent of t h e houses sampled had c o n c r e t e s l a b f o u n d a t i o n s w h i c h d e c r e a s e s c o n s i d e r a b l y t h e volume of wood r e q u i r e d . Few houses a r e c o n s t r u c t e d i n Canada w i t h s u c h f o u n d a t i o n s , w h i c h w o u l d t e n d t o i n c r e a s e C a n a d i a n consumption p e r u n i t above t h a t shown i n T a b l e 8. A p p r o x i m a t e l y 91 p e r c e n t o f t h e sampled houses had wood.frame ex-t e r i o r w a l l s , w h i c h i s p r o b a b l y c l o s e t o t h e C a n a d i a n s i t u a t i o n . How t h e s e f a c t o r s i n f l u e n c e wood cons u m p t i o n p e r u n i t i s shown i n T a b l e 9 u s i n g d a t a f o r 1962; W i t h t h e p r o b a b l e d i f f e r e n c e s w h i c h e x i s t between houses b u i l t i n t h e U.S.A. and Canada, i t would n o t be e n t i r e l y a c c e p t -a b l e t o assume t h a t f i g u r e s p r e s e n t e d i n T a b l e s '8.. and 9 a r e a p p l i c a b l e t o Canada. WOOD USED PER UNIT IN-SINGLE-FAMILY HOUSES INSPECTED BY THE FEDERAL HOUSING ADMINISTRATION, 1962 and 1968 INSULATION PARTICLE SHINGLES. LUMBER PLYWOOD HARDBOARD BOARD BOAR© & SHAKES YEAR ( b d . f t . ) ( s q . f t . - 3/8 i n ; ) ( s q . f t . - 1/4 i n . ) ( s q . f t ; - 1/2 i n . ) ( s q . f t . - 3/4 i n . ) ( S q u a r e s ) F l o o r and f o u n d a t i o n s 1962 2,633 1968 2,126 488 1,386 9 22 31 131 W a l l s and 1962 3,387 p a r t i t i o n s 1968 3,387 347 277 333 571 720 677 0.6 0.1 Roof and c e i l i n g 1962 1968 3,070 2,927 1,080 1,578 1 30 65 2.4 3.6 M i l l w o r k and t r i m 1962 1968 1,6.11 1,831 467 917 164 469 A * 39 49 TOTAL 1962 10,701 2,382 507 750 70 3.0 1968 10,271 4,158 1,062 742 180 3.7 L e s s t h a n 0.5 s q . f t . Source: P h e l p s , R. B. 1970. Wood P r o d u c t s Used i n S i n g l e - F a m i l y Houses I n s p e c t e d by t h e F e d e r a l H o u s i n g A d m i n i s t r a t i o n , 1959, 1962 and 1968. t o O N TABLE 9 WOOD USED PER UNIT* BY CONSTRUCTION CHARACTERISTICS, 1962 . - _.,v • • ' - INSULATION PARTICLE LUMBER -PLYWOOD BOARD. BOARD ( s q . f t . ( s q . f t . ( s q . f t . (bd. f t . ) 3/8 i n . ) - 1/2 i n . ) - 3/4 i n . ) S t o r e y s : O n e - s t o r e y 9,394 1,947 750 68 1 1 / 2 - two 12,080 2,970 558 97 S p l i t l e v e l 13]O07 3,234 850 66 F o u n d a t i o n : N o n - s l a b ' 1 1 , 8 2 3 2,508 766 92 S l a b 7,387 1,673 730 41 E x t e r i o r w a l l : Wood; frame 10,400 2,205 840 74 Masonry 6,820 1,829 84 48 E x c l u d i n g wood used f o r e x t e r i o r w a l l s i d i n g . Source:. P h e l p s , R. B., 1966. Wood P r o d u c t s Used i n S i n g l e - F a m i l y Houses I n s p e c t e d by t h e F e d e r a l H o u s i n g A d m i n i s t r a t i o n , i 9 5 9 and 1962. F i g u r e s showing wood use p e r d w e l l i n g ..unit were a l s o p r e s e n t e d by t h e U.S. F o r e s t S e r v i c e i n "Timber Trends i n the U n i t e d S t a t e s " (U.S..: D.A., 1965). T h e i r d a t a f o r 1962, and p r o j e c t i o n s f o r 1970 and 1980 a r e p r e s e n t e d i n T a b l e 10. A s u b s t a n t i a l d i f f e r e n c e i i i wood consumption b e -tween d w e l l i n g t y p e s i s e v i d e n t . I n 1962, one and two f a m i l y d w e l l i n g s TABLE 10 WOOD PRODUCTS CONSUMED PER DWELLING U N I T + ., LUMBER PLYWOOD AND VENEER BUILDING BOARD" (bd. f t . ) ( s q . f t . - 3/8 i n . ) ( s q . f t . - 1/2 i n . ) ONE AND MULTI- ONE AND MULTI- ONE AND MULTI-YEAR . TWO FAMILY FAMILY TWO FAMILY . FAMILY TWO FAMILY FAMILY 1962 11,190 4,500 3,010 1,800 1,320 350 1970 10,740 4,280 3,610 1,820 1,480 360 1980 10,290 4,050 4,010 1,830 1,720 370 + E s t i m a t e s i n c l u d e a l l o w a n c e f o r m a n u f a c t u r i n g and o n - s i t e w a s t e . * I n c l u d e s i n s u l a t i o n b o a r d , h a r d b o a r d , and p a r t i c l e b o a r d . S o u r c e : U .S.D.A. 1965. Timber Trends i n t h e U n i t e d S t a t e s . consumed a p p r o x i m a t e l y 2-1/2 t i m e s more lumber, 66 p e r c e n t more plywood and v e n e e r , and a l m o s t f o u r t i m e s more b u i l d i n g b o a r d t h a n d i d m u l t i -f a m i l y d w e l l i n g s on a p e r u n i t b a s i s . I t s h o u l d be n o t e d t h a t t h e f i g -u r e s f o r m u l t i - f a m i l y d w e l l i n g s i n c l u d e b o t h h i g h - r i s e and l o w - r i s e a p a r t m e n t s . The volume of lumber employed i n t h e s e u n i t s ranged f r o m about 1,200 bd. f t . p e r u n i t i n h i g h - r i s e apartments t o 5,600 b d . f t . p e r u n i t i n t h e l o w - r i s e v a r i e t y . No comparable f i g u r e s appear t o be' a v a i l a b l e f o r plywood, h a r d b o a r d , p a r t i c l e b o a r d , o r i n s u l a t i o n b o a r d . The p r o j e c t i o n s i n d i c a t e t h a t lumber, consumption p e r u n i t i s e x p e c t e d t o c o n t i n u e i t s d e c l i n e i n t h e f u t u r e , w h i l e plywood and b u i l d i n g b o a r d i n c r e a s e i n p e r u n i t c o n s u m p t i o n . More recently, Hair and U l r i c h (1967) have indicated that m u l t i -family units require only 2/5 as much lumber and 3/5 as much plywood as single-family dwellings. The close correspondence between these r a t i o s and r a t i o s which could be calculated from figuresgpresented i n Table 10 would suggest that they were derived from "Timber Trends i i i the United States." Several other figures on wOod consumption i n r e s i d e n t i a l construc-t i o n . a r e w w o r i h r . n o i E u n g . According to the American Plywood Association, plywood,use per single-family dwelling was 5,500 sq, f t . i n 1968 and was expected to r i s e to 5,700 sq. f t . by 1970 and 6,000 sq. f t . by 1972 (Lam-bert, 1969). There i s evidence that Canadian houses are on the average considerably smaller than i n the U.S.A., and hence the consumption of plywood (and other wood products) per unit may be considerably lower. According to the same author, the average floor* area of FHA-insured houses i n the U.S.A. was 1,365 sq. f t . i n 1963 and 1,570 sq. f t . i n 1967. The'a'.comparable Canadian figures f o r NHA-insured houses are 1,136 sq. f t . and 1,15,3 sq. f t . f o r 1963 and 1967, re s p e c t i v e l y (CMHC, 1969a). Lewis (1969) recently indicated that U.S. p a r t i c l e board con-sumption i n 1965 was 65 sq. f t . per one and two family u n i t s , and 35 sq. f t . per apartment u n i t . Hardboard consumption was reportedly 640 sq. f t . and'180 sq. f t . per unit for one and two family dwellings and apartments, r e s p e c t i v e l y . With such l i t t l e data av a i l a b l e on the consumption of wood pro-ducts by type of dwelling, the impact of current trends.toward r e l a t i v e -l y more apartments and fewer single-family houses i s d i f f i c u l t to e s t i -mate q u a n t i t a t i v e l y , although i t i s undoubtedly large. Some of t h e problems o f a p p l y i n g A m e r i c a n d a t a t o Canada have a l r e a d y been p o i n t e d o u t . A n o t h e r p r o b l e m i s t h a t t h e r e i s no e v i d e n c e t h a t t h e p r o p o r t i o n o f l o w - r i s e t o h i g h - r i s e a partments i s t h e same i n b o t h c o u n t r i e s . A f u r t h e r c o m p l i c a t i o n i s t h a t t h e p r o p o r t i o n s o f p r e -f a b r i c a t e d d w e l l i n g s i n t h e two c o u n t r i e s may d i v e r g e c o n s i d e r a b l y . P l a t t s (1964b) e s t i m a t e d t h a t about 35 p e r c e n t o r more of U.S. j s i n g l e -f a m i l y d w e l l i n g s were p r e f a b r i c a t e d i n 1962, compared t o 15 p e r c e n t f o r Canada a t t h e t i m e o f h i s r e p o r t . The U.S.D.A. (1965) r e p o r t e d t h a t t h e co n s u m p t i o n o f lumber p e r u n i t i n p r e f a b r i c a t e d s i n g l e - f a m i l y u n i t s i s s u b s t a n t i a l l y b e l o w t h a t used i n c o n v e n t i o n a l l y c o n s t r u c t e d u n i t s . These two c o n s i d e r a t i o n s , c o u p l e d w i t h t h e p r e v i o u s l y m e n t i o n e d problems appear t o i n v a l i d a t e . t h e use of A m e r i c a n d a t a , s u c h as c o n t a i n e d i n T a b l e s 8 and 10, f o r a p p l i c a t i o n i n Canada. I t c a n o n l y be c o n c l u d e d t h a t i n Canada• apa r t m e n t s p r o b a b l y use from o n e - t H i r d t o o n e - h a l f t h e volume o f wood p r o d u c t s t h a t c o n v e n t i o n a l houses use on a p e r u n i t b a s i s , and t h a t t h e c u r r e n t t r e n d i n d w e l l i n g , t y p e s i s h a v i n g a heavy impact on t h e demand f o r wood i n . r e s i d e n t i a l c o n s t r u c t i o n . FACTORS INFLUENCING CHOICE OF MATERIALS IN RESIDENTIAL CONSTRUCTION Compelling w i t h wood i n t h e r e s i d e n t i a l c o n s t r u c t i o n market a r e a h o s t o f p r o d u c t s f a l l i n g i n t h e c a t e g o r i e s o f n o n - m e t a l l i c m i n e r a l s , m e t a l s , and p l a s t i c s . How t h e s e p r o d u c t s f a r e i n t h e h o u s i n g market i s dependent upon numerous f a c t o r s , any one of. which.may p r o h i b i t t h e use of a p r o d u c t r e g a r d l e s s o f how w e l l i t meets o t h e r r e q u i r e m e n t s . I n some i n s t a n c e s t h e r e I s l i t t l e t a n g i b l e e v i d e n c e i n d i c a t i n g how c e r t a i n f a c -t o r s do i n f l u e n c e the c h o i c e o f m a t e r i a l s , and o f t e n s t a t i s t i c a l d ataware l a c k i n g . N e v e r t h e l e s s , an e x a m i n a t i o n o f t h e s e f a c t o r s , t o t h e e x t e n t p e r m i t t e d by a v a i l a b l e i n f o r m a t i o n , i s e s s e n t i a l t o t h i s s t u d y . T r a d i t i o n Wood frame c o n s t r u c t i o n , d e v e l o p e d o v e r t h e p a s t two c e n t u r i e s , i s t r a d i t i o n a l i n Canada, and has t y p i c a l l y c a l l e d f o r l a r g e volumes of so f t w o o d lumber and o t h e r wood p r o d u c t s {McCanee,; 1969a) . Wood frame c o n s t r u c t i o n has p r o v e d t o be a d a p t a b l e t o t e m p e r a t u r e extremes from -40°F t o 100°F and has been used e c o n o m i c a l l y i n b o t h s i n g l e - and m u l t i - f a m i l y d w e l l i n g s , w i t h h e i g h t l i m i t a t i o n s .of t h r e e s t o r e y s ( O r r , 1 9 6 6 ) . S i n c e 1940, p r e f a b r i c a t i o n i n wood.frame c o n s t r u c t i o n has been.adopted on an i n c r e a s i n g s c a l e , w i t h components m a n u f a c t u r e d o f f - s i t e and ship.ped t o t h e b u i l d i n g , s i t e . f o r a s s e m b l y . A l t h o u g h . h o u s e c o n s t r u c t i o n i s . o f t e n c i t e d by c r i t i c s as. b e i n g v e r y backward and i n e f f i c i e n t , . D i c k e n s 0-969) m a i n -t a i n s , t h a t house . b u i l d e r s have a.good r e c o r d f o r h o l d i n g down c o n s t r u c t i o n c o s t s . He i n d i c a t e d t h a t i n . s p i t e o f a c o s t i n c r e a s e o f 51 p e r c e n t f o r m a t e r i a l s and 136 p e r c e n t f o r l a b o r i n . t h e 19.49-65 p e r i o d , house c o n s t r u c -t i o n c o s t s r o s e by o n l y . 4 4 p e r c e n t o v e r t h e same p e r i o d . I n c o m p a r i s o n t o p r i c e movements of o t h e r consumer d u r a b l e s , house p r i c e s have n o t p e r f o r m e d as w e l l as D i c k e n s i m p l i e d . The consumer p r i c e i n d e x f o r new houses i n 1970 (1961 = 100) was 161.4, compared t o 96.6 f o r a p p l i a n c e s , 126.2 f o r f u r n i t u r e , and 98.8 f o r new p a s s e n g e r c a r s : Seen i n t h i s p e r s p e c t i v e , house b u i l d e r s have n o t k e p t p r i c e s (and p r e s u m a b l y ? c o s t s ) down t o t h e l e v e l s a t t a i n e d by p r o d u c e r s o f o t h e r consumer d u r a b l e s . Y e t i t i s m a i n -t a i n e d t h a t wood frame c o n s t r u c t i o n i s s t i l l d i f f i c u l t t o s u r p a s s f o r v e r -s a t i l i t y , s t r u c t u r a l adequacy, and low c o s t p r o d u c t i o n ( O r r , 1966). T r a d i t i o n a l ways o f p e r f o r m i n g t a s k s embody t h e a s s u r a n c e o f t h e t e s t o f t i m e . P r o v e n methods s u c h as wood frame c o n s t r u c t i o n p r o v i d e r e l i a b i l i t y and e n t a i l l e s s r i s k f o r e n t r e p r e n e u r s i n t h e house b u i l d i n g i n d u s t r y . T h i s a p p l i e s b o t h t o b u i l d e r s and t o s u p p l i e r s o f mortgage money, who a r e r e p o r t e d t o be e x t r e m e l y c o n s e r v a t i v e i n t h e i r a p p roach t o new b u i l d i n g d e s i g n s , methods, and m a t e r i a l s . I t wou l d t h u s appear t h a t wood s u p p l i e r s have t h e w e i g h t . o f t r a d i t i o n i n t h e i r f a v o u r . Too-much emphasis s h o u l d . n o t be p l a c e d on t h e i n f l u e n c e o f t r a d -i t i o n a l f a c t o r s i n t h e f u t u r e . Over t i m e , as t h e b u i l d i n g i n d u s t r y deve-. l o p s more s o p h i s t i c a t e d management t e c h n i q u e s , and more h i g h l y e d u c a t e d i n d i v i d u a l s e n t e r t h e f i e l d , the.bonds of t r a d i t i o n w i l l , l o s e t h e i r h o l d and a l l o w f o r i n n o v a t i o n s i n b u i l d i n g t e c h n i q u e s and m a t e r i a l s .which p r o -v i d e economies I n p r o d u c t i o n . L a the. s h o r t t e r m , t r a d i t i o n . w i l l p r o b a b l y h a ve.a s t r o n g e r e f f e c t t h a n o v e r t h e l o n g r u n . A v a i l a b i l i t y C l o s e l y a s s o c i a t e d w i t h , t h e development of wood as t h e t r a d i t i o n -a l b u i l d i n g m a t e r i a l i n Canada was i t s a v a i l a b i l i t y i n - l a r g e volumes. The e a r l y s e t t l e r s , i n c l e a r i n g l a n d . f o r b u i l d i n g s and f a r m s , had s u f f i -c i e n t wood a t t h e i r , d i s p o s a l i f o r a l l of t h e i r , b u i l d i n g needs. At t h a t t i m e t h e t e c h n o l o g y f o r making s u i t a b l e m e t a l s and p l a s t i c s a v a i l a b l e f o r b u i l d i n g had n o t been d e v e l o p e d . I n d e e d , a t t h a t t i m e t h e v a s t m i n -e r a l d e p o s i t s i n Canada .were v i r t u a l l y unknown. The s i t u a t i o n has now changed w i t h t h e d i s c o v e r y of . s u b s t a n t i a l volumes of b o t h f e r r o u s and n o n - f e r r o u s m i n e r a l o r e b o d i e s as w e l l as v a s t p e t r o l e u m r e s o u r c e s . The a v a i l a b i l i t y o f t h e s e m a t e r i a l s i s , t h e r e f o r e , no l o n g e r a l i m i t i n g f a c t o r . U n l i k e t h e f o r e s t r e s o u r c e , m i n e r a l r e s o u r c e s are..non-renewable, thus i m p l y i n g i n c r e a s i n g c o s t i n d u s t r i e s due t o e x t e r n a l , d i s e c o n o m i e s (Mead, 1966). B u t , i t can a l s o be argued t h a t s i m i l a r e x t e r n a l d i s e c o n o -mies e x i s t i n t h e f o r e s t i n d u s t r i e s i n t h a t . i n c r e a s i n g e x p e n d i t u r e s w i l l be r e q u i r e d t o manage t h e f o r e s t s a t a l e v e l s u f f i c i e n t t o e nsure s u s -t a i n e d o r i n c r e a s i n g y i e l d s . I n a d d i t i o n , i t may be n o t e d t h a t d e c r e a s -i n g q u a l i t y and s i z e o f t h e t i m b e r r e s o u r c e , and i n c r e a s i n g d i s t a n c e s t o m e r c h a n t a b l e s t a n d s , have been s i g n i f i c a n t f a c t o r s c o n t r i b u t i n g t o h i g h e r c o s t s and t h e l o s s . o f . m a r k e t s f o r wood. F o r t h e f o r e s e e a b l e f u t u r e , r e l a -t i v e a v a i l a b i l i t y . o f r e s o u r c e s , e x c e p t perhaps f o r r e g i o n a l d i s p a r i t i e s , s h o u l d . n o t . s i g n i f i c a n t l y i n f l u e n c e t h e . u s e of m a t e r i a l s . I n ; . c o n s t r u c t i o n . P r i c e , of M a t e r i a l s . R e l a t i v e p r i c e s o f . competing .materials;, a r e one of t h e most i m p o r -t a n t f a c t o r s i n f l u e n c i n g m a t e r i a l s c h o i c e . R e a l p r i c e s a r e o f t e n e l u s i v e b e c a u s e of a d d i t i o n a l p r i c e f a c t o r s n o t i n c l u d e d i n p r i c e q u o t a t i o n s . These i n c l u d e d i s c o u n t s , a s s e m b l y o r e r e c t i o n c o s t s , and f r e q u e n c y o f m a i n t e n a n c e i n h e r e n t w i t h , a g i v e n m a t e r i a l . Because o f t h e m u l t i p l i c i t y o f f i r m s , p r o d u c t s and p r i c i n g p o l i c i e s , , i t i s i m p o s s i b l e t o e v a l u a t e t h e i n f l u e n c e o f most o f t h e s e a d d i t i o n a l , p r i c e v a r i a b l e s , in...anything b u t a p r o d u c t - b y - p r o d u c t c o m p a r i s o n . Such a d e t a i l e d a n a l y s i s w i l l n o t be e n t e r e d i n t o h e r e . I n s t e a d , a c o m p a r i s o n o f r e l a t i v e p r i c e s o f m a t e r -i a l s w i i l . b e made i n order, t o h e l p e v a l u a t e , t h e p r i c e p o s i t i o n of wood and wood p r o d u c t s w i t h . r e s p e c t t o c o m p e t i t i v e m a t e r i a l s . Wood p r o d u c t s have m a i n t a i n e d a f a v o u r a b l e p r i c e p o s i t i o n r e l a -t i v e t o competing p r o d u c t s , a s i t u a t i o n w h i c h l a r g e l y a c c o u n t s f o r t h e i r w i d e s p r e a d use f o r r e s i d e n t i a l c o n s t r u c t i o n . There i s , however, s u b s t a n -t i a l e v i d e n c e t h a t t h e p r i c e advantage h e l d by wood p r o d u c t s h a s been g r a d u a l l y d i m i n i s h i n g o v e r most of t h i s c e n t u r y . Zaremba (1958) i n d i c a t e d t h a t t h e w h o l e s a l e p r i c e i n d e x o f a l l commodities i n t h e U.S.A. remained r e l a t i v e l y s t a b l e o v e r t h e p e r i o d 1860 t o 1955, w h i l e lumber p r i c e s s t e a d i l y r o s e above t h e a l l - c o m m o d i t i e s i n d e x , f o l l o w i n g r o u g h l y a t h r e e p e r c e n t t r e n d l i n e . P o t t e r and C h r i s t y (1962) a l s o i n d i c a t e d t h a t , over t h e 1870-1957 p e r i o d , o n l y t h e f o r e s t p r o d u c t s s e c t o r , showed an i m p o r t a n t u p t r e n d i n p r i c e s , w h i c h was accompanied by a d e c l i n e i n p e r c a p i t a c o n -s u m p t i o n . S i n c e . t h e U..S. market has,, always been an, o v e r r i d i n g f a c t o r I n t h e d e t e r m i n a t i o n of lumber p r i c e s , i n . Canada (Widman, 1969)., t h e i r o b s e r -v a t i o n s a r e . p r o b a b l y e q u a l l y a p p l i c a b l e t o t h e C a n a d i a n s i t u a t i o n . . I n F i g u r e 5 t h e movement of t h e C a n a d i a n g e n e r a l w h o l e s a l e p r i c e i n d e x i s i l l u s t r a t e d a l o n g w i t h , some of i t s . m a j o r components, o v e r t h e p e r -i o d 1940 t o 1968. The i n c r e a s e i n t h e p r i c e o f wood p r o d u c t s i s shown t o have g r e a t l y exceeded t h e i n c r e a s e s i n o t h e r p r o d u c t g r o u p s . As of 1968, o o o CO I IT) co o (1) _ Q £ z X c 380 -340 -300 — 2 6 0 -220 180 -140 -General wholesale index Non-ferrous metal products Non-metallic mineral products Wood products Iron products 1940 1950 1960 Year Figure 5. Wholesale price indexes in Canada Source: DBS, 1951. Wholesale Price Indexes, 1913-1950. DBS, 1953-69. Prices and Price Indexes. the wholesale p r i c e index of wood products stood at 367.9 as compared to 276.8 for i r o n products, 250.8 for.non-ferrous metals products, and 206.0 for non-metallic minerals products. Zaremba CL958) explained the d i v e r -gence of lumber p r i c e s above all-commodity prices as being r e l a t e d to the divergence of the cost structure of the lumber industry from that of the whole economy. In the long run, prices must cover average costs of produc-t i o n , hence lumber p r i c e s w i l l p a r a l l e l the trend i n average costs of pro-duction. Thus, the high lumber prices noted represent the divergence of the cost structure of the lumber,industry from the cost structure of the economy. He further r e l a t e d the r i s i n g cost structure of the lumber i n -dustry to the f a i l u r e of that industry to increase the p r o d u c t i v i t y of labour as wages and p r o d u c t i v i t y increased throughout.the economy. More s p e c i f i c to the housing market are the p r i c e index numbers of r e s i d e n t i a l b u i l d i n g materials shown i n Figure 6. The o v e r a l l form: of these curves i s s i m i l a r to the wholesale p r i c e indexes i n Figure 5; but p r i c e s of r e s i d e n t i a l b u i l d i n g materials have r i s e n at a f a s t e r rate. In the period from 1940 to 1951, the prices of lumber and lumber products i n -creased at asrauch higher rate than other b u i l d i n g materials. Calculated from the 1935-39 base years, prices of lumber products had increased 325 per cent by 1951, compared to 41 per cent for concrete products., 81 per cent f o r bricks,,, and 113 per cent for. metal products. R e l a t i v e l y stable p r i c e s prevailed during the remainder, of the 195Q's1!5but, since 1962, the p r i c e s of .lumber products used In housing have again, accelerated r a p i d l y , while increases i n the .prices of other b u i l d i n g materials, have been, minor i n comparison. I t should.be noted that the t o t a l p r i c e index.of resid e n t t i a l b u i l d i n g materials has c l o s e l y followed the pattern of lumber prices 400 200 Total - all products Metal products Lumber and lumber products Concrete products Bricks / / 1 _1__J I I u 1940 1950 Year 1960 Figure 6. Price index numbers of residential building materials in Canada Source: DBS, 1953—69. Prices and Price Indexes. t h r o u g h o u t t h e p e r i o d shown, e v i d e n c e of t h e s t r o n g i n f l u e n c e of lumber p r o d u c t s i n t h e t o t a l i n d e x . I n 1968,.the b u i l d i n g m a t e r i a l s i n d e x f o r lumber p r o d u c t s s t o o d a t 577 compared t o 189 f o r c o n c r e t e p r o d u c t s ,1*263 f o r b r i c k s , and 262 f o r m e t a l p r o d u c t s . T h i s r e p r e s e n t s a s u b s t a n t i a l d e c r e a s e i n t h e p r i c e advantage of lumber p r o d u c t s . E c o n o m i s t s have d i s t i n g u i s h e d two t y p e s of b u i l d i n g c y c l e s : a s h o r t c y c l e about t h e same l e n g t h as t h e g e n e r a l b u s i n e s s c y c l e , and a l o n g c y c l e o f a p p r o x i m a t e l y 15 t o 20 y e a r s . Z i v n u s k a (1952) has shown t h a t t h e c o n s u m p t i o n of lumber i n c o n s t r u c t i o n i s c l o s e l y r e l a t e d t o s h o r t b u i l d i n g c y c l e s ( w h i c h i n t u r n had c o r r e s p o n d e d c l o s e l y t o g e n e r a l b u s i n e s s . c y c l e s over t h e p e r -i o d he i n v e s t i g a t e d ) . There was l e s s e v i d e n c e of a r e l a t i o n s h i p e x i s t -i n g between lumber c o n s u m p t i o n and t h e l o n g c y c l e , l a r g e l y due t o a l a c k o f lumber c o n s u m p t i o n d a t a o v e r a s u f f i c i e n t l y l o n g p e r i o d . R e s i d e n t i a l c o n s t r u c t i o n , t h e most i m p o r t a n t s i n g l e s o u r c e o f lumber demand, i s s u b j e c t t o p a r t i c u l a r l y v i o l e n t c y c l i c a l f l u c t u a t i o n s . B o t h W h i t e (1967) i n Canada, and Mead (1961) i n t h e U n i t e d S t a t e s , have i n d i c a t e d t h a t , s i n c e World War I I , t h e r e has been a t e n d e n c y f o r c y c l e s i n r e s i d e n t i a l c o n s t r u c t i o n t o move c o n t r a c y c l i c a l l y (as opposed to p r o -c y c l i c a l movements between t h e two W o r l d Wars).. -This c o n t r a c y c l i c a l move-ment i n r e s i d e n t i a l c o n s t r u c t i o n . h a s been r e l a t e d t o t h e a c t i o n o f g o v e r n -ment s p o n s o r e d mortgage a i d programs;.-.(EHA-VA.mortgages, i n the. U n i t e d , S t a t e s , and NHA mortgages i n . Canada). I t i s e x p l a i n e d by b o t h of t h e above a u t h o r s t h a t d u r i n g p e r i o d s , o f s . t r e n g t h i n t h e w h o l e economy, . i n t e r e s t r a t e s , a r e h i g h and r i s i n g , w i t h t h e r e s u l t t h a t l i m i t e d funds a r e a v a i l a b l e f o r l o w -i n t e r e s t g o v e r n m e n t - i n s u r e d mortgages.. C o n v e r s e l y , when t h e economy i s s l o w i n g down and i n t e r e s t r a t e s . f a l l i n g , g o v e r n m e n t - i n s u r e d mortgages become more a t t r a c t i v e , hence t h e c o n t r a c y c l i c a l a c t i v i t y i n r e s i d e n t i a l c o n s t r u c t i o n . The s i g n i f i c a n c e o f t h e s e c y c l e s to. t h e lumber i n d u s t r y l i e s • i n t h e f a c t t h a t t h e demand f o r lumber i s a d e r i v e d demand. Thus;, c y c l i c a l f l u c t u a t i o n s i n b u i l d i n g a c t i v i t y r e s u l t i n s i m i l a r f l u c t u a t i o n s , i n t h e demand f o r lumber. A l t h o u g h b u i l d i n g c y c l e s have been s t r e s s e d above, th e demand f o r lumber i n i n d u s t r i a l u s e s i s s i m i l a r l y r e l a t e d t o . b u s i n e s s c y c l e s . The development o f c y c l e s i n lumber p r o d u c t i o n thus depends on t h e combined i n f l u e n c e . o f b u i l d i n g and b u s i n e s s c y c l e s , t h e i r r e l a t i v e i m p o r t a n c e i n d e t e r m i n i n g lumber demand depending, on t h e g e n e r a l l e v e l o f a c t i v i t y i n e a c h , and t h e a m p l i t u d e o f t h e i r r e s p e c t i v e c y c l i c a l move-ments . I n a d d i t i o n t o c y c l i c a l f l u c t u a t i o n s , lumber p r i c e s have t y p i c a l l y f o l l o w e d a c l e a r p a t t e r n o f s e a s o n a l b e h a v i o r , as de m o n s t r a t e d by Mead (1964) f o r p o n d e r o s a p i n e and D o u g l a s - f i r . T h i s s e a s o n a l p a t t e r n has been a t t r i b u t e d t o t h e s e a s o n a l n a t u r e o f c o n s t r u c t i o n a c t i v i t y w h i c h p i c k s up i n t h e s p r i n g and i s m a i n t a i n e d .at.a h i g h l e v e l t h r o u g h o u t t h e summer. N o r m a l l y , lumber p r i c e s have.peaked d u r i n g f i v e . d i f f e r e n t months f r o m A p r i l t o September and a r e a t a low. between November? and,January (Mead, 1 9 6 4 ) . F l u c t u a t i o n s i n . l u m b e r demand, a s e f f e c t e d t h r o u g h c y c l i c a l . m o v e -ments i n b u s i n e s s and b u i l d i n g , a r e p r i m a r i l y r e s p o n s i b l e . f o r lumber p r i c e f l u c t u a t i o n s ; . G i v e n a change i n demand, t h e lumber i n d u s t r y ( a p p r o a c h i n g t h e e c o n o m i s t ' s model of p u r e c o m p e t i t i o n ) i s more apt t o a d j u s t t h r o u g h a p r i c e change r a t h e r t h a n a change i n . o u t p u t . The r e s u l t i s t h a t s u b -s t a n t i a l f l u c t u a t i o n s i n lumber p r i c e s t e n d t o o c c u r f r e q u e n t l y i n r e s p o n s e t o changes i n demand. I n a d d i t i o n t o demand c y c l e s t h e . s e a s o n a l i t y o f l o g s u p p l y a l s o i n f l u e n c e s p r i c e l e v e l s . . S e v e r e w i n t e r w e a t h e r , s p r i n g b r e a k - u p , and h i g h f o r e s t - f i r e d anger, can a l l t e r m i n a t e l o g g i n g o p e r a t i o n s , w h i c h , i n t u r n , a f f e c t s l o g and lumber s u p p l y ( R i c h , 1 9 7 0 ) . O t h e r f a c t o r s , s u c h as l a b o u r s t r i k e s and b o x - c a r s h o r t a g e s have a l s o been c i t e d as r e a s o n s f o r lumber s u p p l y s h o r t a g e s . The p r o b l e m of f l u c t u a t i n g p r i c e s , as caused by t h e above i n f l u e n c e s of s u p p l y and demand, and p o s s i b l e s o l u t i o n s w i l l be d i s c u s s e d s u b s e q u e n t l y . H a v i n g o b s e r v e d p r i c e t r e n d s o f wood p r o d u c t s i n r e l a t i o n t o com-p e t i n g m a t e r i a l s , i t i s a p p a r e n t t h a t t h e p r i c e e l a s t i c i t y of demand f o r wood p r o d u c t s r e q u i r e s some d i s c u s s i o n h e r e . The q u e s t i o n t o . b e answered i s : how does an i n c r e a s e i n t h e p r i c e o f lumber ( o r o t h e r wood p r o d u c t s ) i n f l u e n c e t h e demand f o r t h a t p r o d u c t ? T h i s q u e s t i o n i n v o l v e s b o t h p r i c e e l a s t i c i t y o f demand and c r o s s e l a s t i c i t y , w h i c h i s i n c l u d e d i n . t h e f o r m e r . Mead (1966) has p r e s e n t e d a t h e o r e t i c a l d i s c u s s i o n , o f q u a l i t a t i v e f a c t o r s i n f l u e n c i n g t h e p r i c e e l a s t i c i t y o f demand f o r lumber. E l a s t i c i t y o f demand . i n c r e a s e w i t h . t i m e a f t e r , a . p r i c e change. He i n d i c a t e d . t h a t t i m e i s r e q u i r e d t o change f i r m l y e n t r e n c h e d , b u y i n g h a b i t s , t o . : a l t e r . r e g u l a t o r y f a c t o r s , ( s u c h as amendments t o b u i l d i n g , codes, t o p e r m i t the. u s e o f new. m a t e r i a l s ) . , and t o a l l o w r e c e n t l y p u r c h a s e d goods to.wear. o u t . Zaremba (1963) added t h a t t i m e was r e q u i r e d a f t e r a p r i c e i n c r e a s e . f o r t h e t r a i n i n g o f l a b o u r i n t h e use o f new m a t e r i a l s , and f o r new p r o d u c t r e s e a r c h t o f i n d s u b s t i t u t e s . A c c o r d i n g t o Mead 0-966') , p r o b a b l y t h e most i m p o r t a n t d e t e r m i n a n t s o f demand e l a s t i c i t y a r e t h e a v a i l a b i l i t y and s u i t a b i l i t y . o f s u b s t i t u t e s . G i v e n t h a t c l o s e s u b s t i t u t e s a r e a v a i l a b l e , an i n c r e a s e i n t h e p r i c e o f lumber w i l l r e s u l t i n a d e c r e a s e I n t h e demand f o r lumber and a c o r r e s p o n d -i n g i n c r e a s e i n t h e demand;for t h e s u b s t i t u t e , r e f l e c t i n g a h i g h c r o s s e l a s t i c i t y o f demand. On t h e q u e s t i o n o f a v a i l a b i l i t y , he c o n c l u d e d t h a t t h e s u p p l y o f s u b s t i t u t e s of v a r i o u s m a t e r i a l s groups ( m e t a l s and non-m e t a l l i c m i n e r a l s ) was n o t a l i m i t i n g f a c t o r . A l t h o u g h , lumber ( p r i m a r i l y b o a r d s ) has been l a r g e l y r e p l a c e d i n a number o f u s e s by plywood and o t h e r p a n e l p r o d u c t s , t h e r e has been a l a c k o f s a t i s f a c t o r y s u b s t i t u t e s f o r s t r u c -t u r a l lumber. From t h i s v i e w p o i n t , t h e c r o s s e l a s t i c i t y o f demand f o r lumber i s r e l a t i v e l y i n e l a s t i c . However, i t has p r o b a b l y tended t o i n -c r e a s e i n r e c e n t y e a r s as a r e s u l t o f new p r o d u c t developments w h i c h have o c c u r r e d . Zaremba (1963) has s t r e s s e d t h a t even g i v e n a p o s s i b l e s u b s t i -t u t e , consumer p r e f e r e n c e c o u l d p r e v e n t i t s u s e . Mead (1966) f u r t h e r s t a t e d t h a t t h e r e l a t i v e l y s m a l l i m p o r t a n c e o f lumber i n t o t a l c o n s t r u c t i o n c o s t s , t o g e t h e r w i t h t h e p r o b a b l e i n e l a s t i c demand f o r r e s i d e n t i a l c o n s t r u c t i o n , would s u p p o r t t h e t h e o r y o f an i n e l a s -t i c demand c o n d i t i o n f o r lumber. On t h e other, hand, Zaremba (1963) c a u -t i o n e d a g a i n s t s u c h : a c o n c l u s i o n , s i n c e even a s m a l l c o s t r e d u c t i o n may be s i g n i f i c a n t , i n a. h i g h l y c o m p e t i t i v e c o n s t r u c t i o n i n d u s t r y . . Zaremba . (1963) i n t r o d u c e d i n - p l a c e c o s t , as a f u r t h e r c o n s i d e r a t i o n , , i n d i c a t i n g , t h a t t h e f i n a l purchaser, o f a house i s n o t i n t e r e s t e d i n the. c o s t . of. I n d i v i d u a l m a t e r i a l s b u t t h e p u r c h a s e p r i c e o f t h e co m p l e t e d d w e l l i n g . Taken, t o g e t h e r , Mead (1966) c o n c l u d e d t h a t t h e e v i d e n c e i n d i c a t e d t h a t t h e demand f o r lumber w a s . i n t h e i n e l a s t i c range b u t was becoming more e l a s t i c o v e r t i m e . The h i s t o r i c a l l y h i g h s o f t w o o d lumber p r i c e s r e a c h e d i n t h e s p r i n g o f 1969 have, p e r h a p s , b r o u g h t w i t h them some e v i d e n c e t h a t t h e demand f o r lumber i s becoming more e l a s t i c . .The. c o u r s e of t h e s e r e c e n t p r i c e t r e n d s a r e p l o t t e d i n F i g u r e 7 f o r D o u g l a s - f i r lumber and plywood. O t h e r s o f t -wood s p e c i e s e x p e r i e n c e d s i m i l a r p r i c e t r e n d s o v e r t h e 1967—69 p e r i o d . I n t h e s a m e ' i l l u s t r a t i o n , t h e r e l a t i v e l y s t a b l e p r i c e p a t t e r n s f o r c l a y p r o d u c t s , s t e e l s h e e t s and s t r i p s , and aluminum s h e e t s and s t r i p s a r e shown f o r c o m p a r i s o n . The s h o r t a g e i n s o f t w o o d lumber s u p p l i e s , w h i c h c o n t r i b u t e d t o t h e s e s h a r p . l u m b e r p r i c e i n c r e a s e s , c r e a t e d a s e r i o u s p r o b l e m f o r Canada's e n t i r e b u i l d i n g i n d u s t r y (Widman, 1969). Growing w o r l d demand f o r Canada's s o f t w o o d lumber has been c i t e d by him as t h e cause of t h i s development. A c c o r d i n g t o C a n a d i a n F o r e s t I n d u s t r i e s ( 1 9 6 9 ) and McCance (1 9 6 9 a ) , t h e s e r a p i d l y i n c r e a s i n g lumber p r i c e s have a c c e l e r a t e d t h e demand . f o r a l t e r -n a t i v e p r o d u c t s . McCance i n d i c a t e d t h a t lumber had ce a s e d t o be c o m p e t i t i v e w i t h many s u b s t i t u t e p r o d u c t s when lumber p r i c e s were n e a r i n g t h e i r peak e a r l y i n 1969. F r e q u e n t p r e s s r e p o r t s of b u i l d e r s t r y i n g out s t e e l s t u d s would.;appear t o b e a r t h i s o u t . G i v e n . s u c h p r i c e t r e n d s as shown i n F i g u r e 7, McCance ( 1 9 6 9 a ) s t a t e d t h a t b u i l d e r s , w i l l . m a k e s t r o n g e f f o r t s . t o r e d u c e t h e lumber c o n t e n t of t h e i r b u i l d i n g s t o t h e l o w e s t p o s s i b l e , l e v e l . S uch r e p o r t s as t h e s e appear t o s u p p o r t , t h e s t a t e m e n t t h a t , lumber demand i s b e -coming more e l a s t i c , On t h e o t h e r hand, t h e s u b s t a n t i a l p r i c e i n c r e a s e s w h i c h , a t t e n d e d t h e r e c e n t s h o r t a g e . i n . s u p p l y i n d i c a t e . t h a t lumber demand i s s t i l l q u i t e i n e l a s t i c , a t l e a s t i n t h e s h o r t r u n . I t s h o u l d be n o t e d t h a t a s ' t h e p r i c e , d i f f e r e n t i a l between wood p r o d u c t s and a l t e r n a t i v e m a t e r i a l s d e c r e a s e s , t h e p r o b a b i l i t y o f c o m p e t i -t i v e p r o d u c t s b e i n g d e v e l o p e d u s i n g t h e s e s u b s t i t u t e m a t e r i a l s I n c r e a s e s . T h i s w o u l d s u g g e s t a g r o w i n g i m p o r t a n c e of r e s e a r c h and development, a t o p i c w h i c h w i l l be d i s c u s s e d i n subsequent pages. P r o d u c e r s o f m e t a l and p l a s t i c p r o d u c t s a r e p a r t i c u l a r l y eager t o e n t e r t h e h o u s i n g market on a l a r g e s c a l e . An i n d i c a t i o n of how t h e i r p r i c e s have been moving i s shown i n F i g u r e 8. P l a s t i c s and s y n t h e t i c r e -s i n s have been d e c r e a s i n g i n p r i c e s i n c e 1961. Aluminum s h e e t s and s t r i p s i n c r e a s e d i n p r i c e between 1961 and 1965, b u t by 1968 were down t o one p e r c e n t above t h e 1961 l e v e l . I n 19,68, c o l d r o l l e d s t e e l s h e e t s and. s t r i p s were o n l y 3.3 p e r c e n t above the 1961 l e v e l . These s p e c i f i c m a t e r i a l s . were chosen f o r c o m p a r a t i v e p u r p o s e s h e r e because t h e y a r e e i t h e r b e i n g employed or most l i k e l y t o be employed i n p r o d u c t s f o r t h e h o u s i n g market. I n c o m p a r i s o n , D o u g l a s - f i r lumber a v e r a g e d a 51.5 p e r c e n t p r i c e i n c r e a s e between 1961 and 1968 w h i l e D o u g l a s - f i r plywood a v e r a g e d a 39.2 p e r c e n t i n c r e a s e . However, i t s h o u l d a l s o be n o t e d t h a t plywood had been d e c r e a s -i n g i n p r i c e f o r many y e a r s p r i o r t o 1961. F i g u r e 9 i l l u s t r a t e s how p r i c e s of some s p e c i f i c wood p r o d u c t s have behaved s i n c e 1961 i n c o m p a r i s o n . w i t h p l a s t i c s . a n d s t e e l . .Mouldr. i n g s . a n d f l o o r i n g a r e a r e a s i n w h i c h . p l a s t i c s m a n u f a c t u r e r s a r e a t t e m p t i n g t o make f u r t h e r i n r o a d s . The*53 per, c e n t i n c r e a s e i n wood,moulding p r i c e s o v e r the. 1961-68 p e r i o d , c o m p a r e . u n f a v o u r a b l y w i t h t h e n i n e p e r c e n t d e c r e a s e i n p l a s t i c and s y n t h e t i c r e s i n , p r i c e s . T h i s , has c e r t a i n l y improved t h e p r o s p e c t s f o r p l a s t i c m a n u f a c t u r e r s a t t e m p t i n g t o compete.In t h i s f i e l d . Figure 8. Industry selling price indexes Source: DBS, 1970b. Industry Selling Price Indexes 1956-68. Mouldings / / i i i i I I I I I I I I L 1955 I960 1965 Year Figure 9. Industry selling price indexes Source: DBS, 1970b. Industry Selling Price Indexes 1956-68. The c o m p e t i t i v e p o s i t i o n o f hardwood f l o o r i n g i s a l s o r a p i d l y d e t e r i o r -a t i n g w i t h r e s p e c t t o p r i c e , m a r k i n g a 33 p e r c e n t p r i c e advance o v e r t h e same p e r i o d . W i t h s t e e l d o ors p r e s e n t l y e n t e r i n g t h e h o u s i n g m a r k e t , t h e i n c r e a s i n g p r i c e s o f wood s l a b and f l u s h d o o r s shown i n F i g u r e 9 w i l l o n l y t e n d t o a c c e l e r a t e t h e a c c e p t a n c e o f t h i s new p r o d u c t . A l t h o u g h f u r t h e r p r i c e c o mparisons c o u l d be made; t h e above s h o u l d be s u f f i c i e n t t o i l l u s t r a t e t h a t wood p r o d u c t s a r e q u i c k l y l o s i n g t h e i r p r i c e a d v a n t a g e , a most c r i t i c a l p arameter o f c o m p e t i t i o n . B u i l d i n g c y c l e s , as t h e s o u r c e o f p r i c e f l u c t u a t i o n s o f wood p r o d u c t s , have been d i s c u s s e d p r e v i o u s l y . The p r o b l e m o f f l u c t u a t i n g p r i c e s w i l l be d i s c u s s e d b e l o w , w i t h p a r t i c u l a r r e f e r e n c e t o p o s s i b l e s t a b i l i z i n g measures. R a p i d p r i c e f l u c t u a t i o n s p r e c l u d e a s t a b l e market and w i l l a l s o i n f l u e n c e b u i l d e r s t o seek a l t e r n a t i v e c o n s t r u c t i o n methods ( C a n a d i a n F o r e s t I n d u s t r i e s , 1 9 6 9 ) . C y c l i c a l . o r o t h e r p r i c e f l u c t u a t i o n s c r e a t e problems f o r t h e b u i l d e r by making p l a n n i n g and e s t i m a t i n g c o s t s o f c o n -s t r u c t i o n d i f f i c u l t . U n expected l a r g e p r i c e i n c r e a s e s may r e s u l t i n a p r o j e c t e d s e l l i n g p r i c e w h i c h exceeds t h e p u r c h a s i n g a b i l i t y o f t h e t a r -g e t market ( R i c h , 1 9 6 9 ) . R a p i d f l u c t u a t i o n o f p r i c e s , as w e l l as h i g h p r i c e s , i s thus a n o t h e r p r o b l e m w h i c h t h e lumber i n d u s t r y i s f a c e d w i t h . C o n s i d e r a b l e i n t e r e s t has been a r o u s e d r e c e n t l y . w i t h r e s p e c t t o f u t u r e s m a r k e t s . f o r "-lumber r and--plywood, a t o o l w i t h w h i c h i t I s hoped t o a t l e a s t p a r t i a l l y a l l e v i a t e t h e above p r o b l e m . S i n c e O c t o b e r 1969, t h r e e commodity exchanges have begun t o s e l l f u t u r e s c o n t r a c t s f o r wood p r o d u c t s . The C h i c a g o M e r c a n t i l e Exchange i s - d e a l i n g i n lumber f u t u r e s , w h i l e t h e C h i c a g o Board o f Trade and t h e New: Y o r k M e r c a n t i l e Exchange a r e h a n d l i n g plywood f u t u r e s c o n t r a c t s ( W h i t e and Conway,,1970). As o f J a n u a r y 1970, t h e p r i c e s of t h e s e commodities were r e l a t i v e l y s t a b l e , p a r t i c u l a r l y i n t h e c a s e of plywood. I t i s s t i l l t o o e a r l y t o d e t e r m i n e whether t h i s m a r k e t i n g t o o l w i l l be s u c c e s s f u l . The amount of . t r a d i n g i n t h e s e c o n -t r a c t s has been s m a l l , as i s t h e u s u a l c a s e f o r a new commodity b e i n g t r a d e d . The e x t e n t of t r a d e p a r t i c i p a t i o n w i l l p r o b a b l y d e t e r m i n e i t s u l t i m a t e s u c c e s s (White and Conway, 1970). One b u i l d e r , commenting on f u t u r e s m a r k e t s , s t a t e d t h a t " a n y t h i n g t h a t p u t s s t a b i l i t y i n t o our mar-k e t s i s a good t h i n g . " ( R i c h , 1 9 6 9 ) . A l t h o u g h t h e t r a d i n g of f u t u r e s c o n t r a c t s s h o u l d t h e o r e t i c a l l y t e n d t o f l a t t e n out p r i c e f l u c t u a t i o n s , t h e degree of s u c c e s s i n d o i n g so w i l l p r o b a b l y be m i n i m a l . I t has been ar g u e d t h a t t h e r e a s o n f o r h a v i n g a commodity market and f o r t h e s p e c u l a t o r e n t e r i n g i t i s t h e f a c t t h a t p r i c e f l u c t u a t i o n does e x i s t , and t h a t t h e e f f e c t of f u t u r e s t r a d i n g on p r i c e s i t u a t i o n s as i n 1968-69 ( w h i c h were d e t e r m i n e d t h r o u g h s u p p l y and demand) w i l l be l i m i t e d ( J o s e p h s o n , 1 9 6 9 ) . The p r i m a r y p u r -pose o f h a v i n g a f u t u r e s market f o r lumber and plywood i s so t h a t b u y e r s and s e l l e r s o f t h e s e commodities w i l l have a means o f h e d g i n g a g a i n s t i n -c r e a s e s and d e c r e a s e s i n p r i c e . . By u s i n g t h e f u t u r e s m a r k e t . t o hedge a g a i n s t p r i c e changes, b o t h b u y e r s and s e l l e r s w i l l be a b l e . t o e s t i m a t e f u t u r e c o s t s and r e v e n u e s much more a c c u r a t e l y and thus e l i m i n a t e much o f t h e . u n c e r t a i n t y i n h e r e n t i n f l u c t u a t i n g p r i c e s . A l t h o u g h , lumber and plywood f u t u r e s m a r k ets have drawn much a t t e n -t i o n r e c e n t l y , t h e r e a r e s e v e r a l o t h e r ways i n w h i c h t h e s e v e r i t y of p r i c e f l u c t u a t i o n s can be r e d u c e d . The f i r s t o f t h e s e i s t h r o u g h g r e a t e r d i v e r -s i f i c a t i o n o f markets s e r v e d by the. f o r e s t i n d u s t r i e s . T h i s i n c l u d e s b o t h i n c r e a s i n g the number of s p e c i f i c end uses f o r wood p r o d u c t s and expand-i n g e x p o r t m a r k e t s t o i n c l u d e a l a r g e r number o f o f f - s h o r e buyers.. By so d o i n g , . t h e demand c y c l e s f o r wood p r o d u c t s a r e more a p t t o be compensating i n t h e i r c y c l i c a l movements, thus r e d u c i n g the p r o b a b i l i t y o f l a r g e p r i c e f l u c t u a t i o n s . The second s u g g e s t e d method of r e d u c i n g lumber p r i c e f l u c t u a t i o n s i s t o i n c r e a s e government s p e n d i n g on p u b l i c h o u s i n g when p r i v a t e e x p e n d i -t u r e s i n r e s i d e n t i a l c o n s t r u c t i o n a r e low. Cou p l e d w i t h t h i s i s t h e need f o r more s t a b l e mortgage f i n a n c i n g methods w h i c h a r e not s u b j e c t t o the v a g a r i e s o f f l u c t u a t i n g market i n t e r e s t r a t e s , and n o t a d v e r s e l y a f f e c t e d by government monetary and f i s c a l p o l i c i e s . W i t h t h e o v e r r i d i n g I n f l u e n c e w h i c h p r e s e n t f i n a n c i n g methods have on t h e development of b u i l d i n g c y c l e s , t h i s a r e a h o l d s c o n s i d e r a b l e o p p o r t u n i t y . f o r t h e development o f . s t a b i l i z i n g measures. A t h i r d method w h i c h would add s t a b i l i t y t o wood.products p r i c e s i s t o a l l o w f o r g r e a t e r f l e x i b i l i t y i n a n n u a l a l l o w a b l e c u t s , ( Z i v n u s k a , 1952). R e l a t i v e l y f i x e d a l l o w a b l e c u t s c r e a t e an i n e l a s t i c t i m b e r s u p p l y c o n d i t i o n , thus r e s t r i c t i n g t h e degree t o w h i c h lumber p r o d u c e r s can respond, t o i n - * c r e a s e d demand. The., r e s u l t , i s t h a t f u r t h e r p r e s s u r e s a r e put on . p r i c e s t h a n i f t i m b e r s u p p l y was n o t so r e g u l a t e d . The a d o p t i o n of a more f l e x -i b l e f o r m u l a f o r d e t e r m i n i n g a l l o w a b l e , c u t t h a n p r o v i d e d b y p r e s e n t l y a d -m i n i s t e r e d s u s t a i n e d y i e l d p o l i c i e s - w o u l d a l l o w , t i m b e r , p r o d u c e r s t o a l i g n , t h e i r t i m b e r h a r v e s t s more c l o s e l y w i t h d e m a n d . c o n d i t i o n s and. hence r e d u c e o r e l i m i n a t e t h e p r e s s u r e s e x e r t e d on.lumber p r i c e s by an i n e l a s t i c t i m b e r s u p p l y . A n o t h e r a i d t o p r i c e s t a b i l i z a t i o n , a k i n t o t h e q u e s t i o n o f t i m b e r s u p p l y , i s t h a t o f improved i n v e n t o r y management. The e x i s t e n c e o f lumber i n v e n t o r i e s e i t h e r t o o l a r g e o r t o p s m a l l r e l a t i v e t o #demand r e s u l t s i n f l u c t u a t i n g p r i c e s (Rolemo, 1971) . Through good i n v e n t o r y , management by i n d i v i d u a l f i r m s , lumber s u p p l y can be more c l o s e l y c o - o r d i n a t e d w i t h de-mand, and s h o u l d a c c o r d i n g l y smooth out lumber p r i c e f l u c t u a t i o n s . C l o s e l y r e l a t e d t o improved i n v e n t o r y management i s t h e need f o r more a c c u r a t e p r e d i c t i o n s o f f u t u r e market . r e q u i r e m e n t s . S i n c e s o p h i s t i -c a t e d market f o r e c a s t i n g t e c h n i q u e s r e q u i r e c o n s i d e r a b l e e x p e r t i s e , i m -p r o v e d market a n a l y s i s c o u l d p r o b a b l y b e s t be approached on an i n d u s t r y -w i d e b a s i s . The measures s u g g e s t e d above f o r a p p r o a c h i n g the p r o b l e m o f f l u c t u a t i n g p r i c e s would p r o b a b l y n o t e l i m i n a t e c y c l i c a l p r i c e movements, bu t c o u l d p o s s i b l y r e d u c e them t o a more a c c e p t a b l e l e v e l . R e s e a r c h and Development R e s e a r c h and development (R & D) i s t h e s o u r c e o f new p r o d u c t s , whether of wood or competing m a t e r i a l s and, as s u c h , . p l a y s a s i g n i f i c a n t r o l e i n any i n d u s t r y f a c i n g c o m p e t i t i o n i n t h e market. As p r e v i o u s l y s t a t e d , wood p r o d u c t s have h i s t o r i c a l l y been p r i c e d a t l e v e l s l o w e r t h a n t h e i r p o s s i b l e s u b s t i t u t e s ; b u t w i t h a d i m i n i s h i n g p r i c e d i f f e r e n t i a l , m a n u f a c t u r e r s o f competing p r o d u c t s w i l l f i n d i t e a s i e r . t o compete f o r t r a d i t i o n a l , wood m a r k e t s . T h e i r a b i l i t y t o do so w i l l l a r g e l y depend on t h e i r s u c c e s s i n d e v e l o p i n g f u n c t i o n a l l y s u i t a b l e p r o d u c t s w i t h r e a s o n a b l e i n - p l a c e c o s t s , The amount of R & D c a r r i e d out by competing i n d u s t r i e s may thus be some i n d i c a t i o n o f t h e i r s u c c e s s i n t h i s a r e a , and of t h e p r o b -a b i l i t y o f t h e i r d e v e l o p i n g new p r o d u c t s t h a t would be c o m p e t i t i v e w i t h wood. I n t h e c o n s t r u c t i o n f i e l d , , t h e m a n u f a c t u r e r s a r e t h e p r i m a r y i n -n o v a t o r s , d e v o t i n g much energy t o t h e development o f new p r o d u c t s (Handegord, 1969). An i m p o r t a n t m o t i v a t i o n i s t o improve p e r f o r m a n c e i n r e l a t i o n t o c o m p e t i t o r ' s p r o d u c t s . C l o s e l y a s s o c i a t e d w i t h t h i s i s r e s e a r c h c a r r i e d out by s p e c i a l t y t r a d e and p r o d u c t a s s o c i a t i o n s . O t h e r h o u s i n g r e s e a r c h a c t i v i t y i n Canada ( r e l a t e d t o b u i l d i n g m a t e r i a l s and methods) i s l a r g e l y c a r r i e d o u t by t h e N a t i o n a l R e s e a r c h C o u n c i l ' s D i v i s i o n o f B u i l d i n g R e s e a r c h and t h e N a t i o n a l House B u i l d e r ' s A s s o c i a t i o n . The D i v i s i o n of B u i l d i n g Re-s e a r c h , t h e main agency i n v o l v e d i n t e c h n i c a l r e s e a r c h r e l a t e d t o c o n s t r u c -t i o n , i n i t i a t e s i t s p r o j e c t s i n r e s p o n s e t o r e q u e s t s made by members of i n -d u s t r y o r p u b l i c a g e n c i e s ( C a n a d i a n C o n s t r u c t i o n A s s o c i a t i o n , 1 9 6 9 ) . On t h e b a s i s o f a v a i l a b l e i n f o r m a t i o n , i t i s n o t p o s s i b l e t o a c c u r a t e l y assess, the p r o p o r t i o n o f t h e i r r e s e a r c h d e v o t e d t o wood p r o d u c t s v e r s u s s u b s t i t u t e m a t e r i a l s . The T e c h n i c a l R e s e a r c h Committee o f the N a t i o n a l House B u i l d e r s A s s o c i a t i o n has b u i l t s e v e n e x p e r i m e n t a l houses w i t h t h e aim o f i n v e s t i g a t -i n g new b u i l d i n g m a t e r i a l s and t e c h n i q u e s (McCance, 1969a). The l a t e s t o f t h e s e s h o u l d be o f p a r t i c u l a r i n t e r e s t t o t h e f o r e s t i n d u s t r i e s due.to i t s u s e o f s t e e l f l o o r j o i s t s , s t e e l s t u d s , and v i n y l s i d i n g , s o f f i t s and f a s c i a (McCance, 1969b). F i n a n c i a l a s s i s t a n c e f o r t h i s r e s e a r c h program has been l a r g e l y p r o v i d e d by CMHC w h i c h c a n . s u p p o r t a v a r i e t y o f h o u s i n g r e s e a r c h programs under t h e terms o f P a r t V of t h e N a t i o n a l H o u s i n g A c t o f 1954 (CMHC, 1969b). I n 1968, t h i s agency p r o v i d e d $212,550 f o r r e s e a r c h i n c o n s t r u c t i o n , and an e s t i m a t e d $308,485 i n 1969. No i n f o r m a t i o n i s a v a i l a b l e c o n c e r n i n g R & D e x p e n d i t u r e s made by manufacturers';: and s u p p l i e r s o f b u i l d i n g m a t e r i a l s s p e c i f i c a l l y f o r , o r c o n t r i b u t i n g t o , i n n o v a t i o n s f o r t h e h o u s i n g m a r ket. But s t a t i s t i c s a r e a v a i l a b l e showing e x p e n d i t u r e s on R & D by i n d u s t r y i n Canada. A l t h o u g h s u c h d a t a do n o t throw l i g h t on t h e e f f e c t i v e n e s s o r s u c c e s s of t h e r e -s e a r c h a c t i v i t y , t h e y g e n e r a l l y i n d i c a t e t h e l e v e l o f e f f o r t d i r e c t e d t o -wards r e d u c i n g c o s t s and i n t r o d u c i n g new p r o d u c t s . T a b l e 11 c o n t a i n s t o t a l i n t r a - m u r a l R & D e x p e n d i t u r e s f o r s e l e c t e d i n d u s t r i e s i n Canada. These d a t a i n c l u d e g r a n t s r e c e i v e d under v a r i o u s r e s e a r c h i n c e n t i v e s p r o -grams s p o n s o r e d by f e d e r a l government a g e n c i e s . The p e r f o r m a n c e of t h e wood i n d u s t r i e s compared t o o t h e r i n d u s -t r i e s i s n o t i m p r e s s i v e j u d g i n g from t h e f i g u r e s i n T a b l e 11. I n 1968, t h e s e i n d u s t r i e s s p e n t o n l y $667,000 on i n t r a - m u r a l R & D compared t o $6,299,000 f o r p r i m a r y f e r r o u s m e t a l s i n d u s t r i e s , $5,845,000 f o r m e t a l f a b r i c a t i n g i n d u s t r i e s , $3,333,000 f o r n o n - m e t a l l i c m i n e r a l p r o d u c t s , and $32,926,000 f o r t h e " o t h e r " c h e m i c a l p r o d u c t s i n d u s t r i e s ( which p r e -sumably i n c l u d e s p l a s t i c s , s y n t h e t i c r e s i n s , and i n d u s t r i a l c h e m i c a l s ) . ' O v e r a l l , t h e wood i n d u s t r i e s , i n 1968, c o n t r i b u t e d a p p r o x i m a t e l y 0.2 p e r ce n t o f t h e t o t a l R & D o u t l a y by m a n u f a c t u r i n g i n d u s t r i e s i n Canada. Whether t h e above f i g u r e s a r e a c c u r a t e i s open t o q u e s t i o n , b u t a r e a c c e p t e d h e r e on t h e b a s i s o f t h e r e b e i n g no a l t e r n a t i v e s o u r c e . The p r e l i m i n a r y n a t u r e o f t h e 1968 f i g u r e s , c o u p l e d w i t h upward r e v i s i o n s . o f p r e l i m i n a r y data, i n t h e p a s t , i n d i c a t e t h a t . t h e .1968 d a t a i n T a b l e 11 a r e p r o b a b l y • c o n -s e r v a t i v e , p a r t i c u l a r l y t h e f i g u r e f o r t h e wood i n d u s t r y . A l t h o u g h f e d e r a l INTRA-MURAL R & D EXPENDITURES IN CANADA, BY INDUSTRY 1965 r 1966 r 1967 1968 P (thousands o f d o l l a r s ) Wood 417 449 1,341 667 P r i m a r y m e t a l s ( f e r r o u s ) 7,621 8,696 6,225 6,299 P r i m a r y m e t a l s ( n o n - f e r r o u s ) 13,834 16,632 20,066 16,199 M e t a l f a b r i c a t i n g 2,456 3,113 4,856 5,845 N o n - m e t a l l i c m i n e r a l p r o d u c t s 1,844 2,795 3,346 3,333 Ot h e r c h e m i c a l p r o d u c t s 30,592 35,970 36,542- 32,926 T o t a l : O t h e r m a n u f a c t u r i n g i n d u s t r i e s 214,784 228,619 240,323 252,393 T o t a l : M a n u f a c t u r i n g i n d u s t r i e s 271,548 296,274 312,699 317,662 r = R e v i s e d p = P r e l i m i n a r y S o u r c e : DBS, 1970a. I n d u s t r i a l R e s e a r c h and Development E x p e n d i t u r e s i n Canada, 1967. government i n - h o u s e r e s e a r c h i s n o t b e i n g p r e s e n t e d h e r e , i t m i g h t be n o t e d t h a t i n t h e 1966-67 f i s c a l y e a r , o p e r a t i n g . a n d c a p i t a l f u n d s expended b y ^ t h e F o r e s t P r o d u c t s L a b o r a t o r i e s i n Ottawa and Vancouver t o t a l l e d $2,240,000 (Department o f F i s h e r i e s and F o r e s t r y , 1 9 6 8 ) . In Table 12, Industry.expenditures on extra-mural R & D are pre-sented for selected i n d u s t r i e s , i . e . , industry funds spent i n support of R & D by contract research organizations and u n i v e r s i t i e s . Again, the wood i n d u s t r i e s , i n supporting $0.2 m i l l i o n . o f extra-mural research i n J 1968, exhibited the lowest degree of p a r t i c i p a t i o n i n comparison with i t s competitors. Metal f a b r i c a t i n g industries were not far ahead, support-ing $0.3 m i l l i o n of such research, whiletthe primary, non-ferrous metals i n -dustry supported the largest amount of extra-mural research with $7.7 m i l l i o n . TABLE 12 EXTRA-MURAL R & D EXPENDITURES IN CANADA, BY INDUSTRY 1965r 1966r 1967 1968P ~ (millions of d o l l a r s ) Wood 0.2 .0.2 0.3 0.2 Primary metals (ferrous) .0.3 0.3 0.5 0.5 Primary metals (non-ferrous) 7.3 l7».33* 7.2 7.7 Metal f a b r i c a t i n g 0.2 0.3 0.4 0.3 Non-metallic mineral products 0.9 1.0 0.8 0.9 Other chemical products 1.3 1.4 1.8 1.7 T o t a l : Other manufacturing i n d u s t r i e s 24.1 26.7 27.4 27.7 To t a l : Manufacturing industries 34.3 37.2 38.3 38.9 r = Revised p = P-relimi'nar-y Source: DBS, 1970a. Expenditures I n d u s t r i a l Research and Development i n Canada, 1967. J u d g i n g from t h e r e l a t i v e e x p e n d i t u r e s on R & D by t h e i n d u s t r y groups o u t l i n e d above, i t would appear th_at s u b s t i t u t e s have a good chance of making f u r t h e r i n r o a d s i n t o t r a d i t i o n a l wood m a r k e t s . I t may be n o t e d t h a t many C a n a d i a n f i r m s a r e f o r e i g n owned, and t h a t much o f t h e r e s e a r c h i s p e r f o r m e d by t h e p a r e n t company and t h e n adap-t e d t o t h e C a n a d i a n s i t u a t i o n ( F i n a n c i a l P o s t , 1969a). S i n c e t h e U n i t e d S t a t e s i s by f a r t h e l a r g e s t . s o u r c e o f f o r e i g n o w n e r s h i p i n Canada, and i n f o r m a t i o n f l o w s r e a d i l y a c r o s s our b o r d e r , A m e r i c a n e x p e n d i t u r e s on. R & D a r e a l s o r e l e v a n t t o some e x t e n t i n Canada. I n T a b l e 13, t o t a l i n -d u s t r i a l r e s e a r c h e x p e n d i t u r e s a r e shown by s e l e c t e d m a n u f a c t u r i n g i n d u s -t r i e s i n t h e U n i t e d S t a t e s . The i n d u s t r i a l groups l i s t e d c l o s e l y c o r r e s p o n d t o t h o s e i n T a b l e 11 f o r Canada. S i m i l a r t o t h e C a n a d i a n c a s e , wood p r o d u c t s i n d u s t r i e s i n t h e U.S.A. o n l y a c c o u n t e d f o r 0.1 p e r c e n t of t h e t o t a l e x p e n d i t u r e on R & D by manu-f a c t u r i n g i n d u s t r i e s i n 1967. The $14 m i l l i o n e x p e n d i t u r e on wood p r o d u c t s r e s e a r c h i n 1967 was s m a l l compared t o $144 m i l l i o n on f e r r o u s m e t a l s and p r o d u c t s , $165 m i l l i o n on f a b r i c a t e d m e t a l p r o d u c t s , $ 1 5 2 . m i l l i o n on s t o n e , c l a y and g l a s s p r o d u c t s , and $206 m i l l i o n on t h e " o t h e r " c h e m i c a l s group. F i g u r e s s u c h as t h e s e h e l p e x p l a i n why s u b s t i t u t e m a t e r i a l s a r e b e g i n n i n g t o compete more f a v o u r a b l y w i t h wood p r o d u c t s . I n t h e U.S.A., f o r e s t p r o -d u c t s i n d u s t r i e s as a whole, ( i n c l u d i n g p u l p and paper) s p e n t a p p r o x i m a t e l y 0.6 p e r c e n t o f s a l e s on R & D i n 1964 compared t o t h e a l l i n d u s t r y a v e r -age o f 4.4 p e r c e n t (McKean, 1966). The c o n c l u s i o n s a r r i v e d a t by McKean were t h a t R & D funds, were e s p e c i a l l y - s m a l l f o r lumber and wood p r o d u c t s , t h a t t h e employment o f s c i e n t i s t s by t h e wood i n d u s t r i e s was f a l l i n g b e -h i n d , and t h a t t h e f o r e s t i n d u s t r i e s have l o s t i m p o r t a n t m a r e k t s due t o " r e s e a r c h i n competing i n d u s t r i e s . A l l t h e s e would appear t o be undeniably-t r u e . U n l e s s t h e R & D e f f o r t o f t h e f o r e s t i n d u s t r i e s i s s u b s t a n t i a l l y i n c r e a s e d , and i s s u c c e s s f u l , one may a n t i c i p a t e a. c o n t i n u i n g l o s s o f mar-k e t s t o s u b s t i t u t e m a t e r i a l s . TABLE 13 FUNDS FOR R & D PERFORMANCE IN THE U.S.A., BY INDUSTRY 1963 1964 1965 1966 1967 ( m i l l i o n s o f d o l l a r s ) Lumber, wood p r o d u c t s and f u r n i t u r e 11 12 12 13 14 P r i m a r y m e t a l s : F e r r o u s m e t a l s and p r o d u c t s 106 116 128 139 144 N o n - f e r r o u s m e t a l s and p r o d u c t s 77 79 85 93 102 F a b r i c a t e d m e t a l p r o d u c t s 153 148 145 154 165 S t o n e , c l a y and g l a s s p r o d u c t s 100 110 117 128 152 Other c h e m i c a l s 214 186 184 188 206 T o t a l 661 651 671 715 783 O t h e r m a n u f a c t u r i n g i n d u s t r i e s 11,693 12,543 13,132 14,343 15,097 T o t a l : M a n u f a c t u r i n g i n d u s t r i e s 12,354 13,194 13,803 15,058 15,880 Sou r c e : N a t i o n a l S c i e n c e F o u n d a t i o n 1969. .Development i n I n d u s t r y , 1967. R e s e a r c h and F u n c t i o n a l \i S u i t a b i l i t y B e f o r e a p r o d u c t can be employed f o r any p u r p o s e , i t must meet t h e f u n c t i o n a l r e q u i r e m e n t s of t h e s p e c i f i e d end u s e . Such r e q u i r e m e n t s a r e v a r i e d i n n a t u r e , r a n g i n g f r o m s t r u c t u r a l p e r f o r m a n c e and d u r a b i l i t y t o sound a b s o r p t i o n p r o p e r t i e s and a e s t h e t i c a p p e a l . I n h e r e n t i n a l l p r o -d u c t s a r e t h e p r o p e r t i e s o f t h e b a s i c m a t e r i a l ( s ) o f w h i c h i t i s composed. I t would be a p p r o p r i a t e t h e r e f o r e t o examine t h e p r o p e r t i e s o f m a t e r i a l s c ompeting i n t h e h o u s i n g m a r k e t , p o i n t i n g out t h e i r s t r e n g t h s and l i m i t a -t i o n s . A l t h o u g h t h e r e a r e l a r g e v a r i a t i o n s i n p r o p e r t i e s between i n d i v i -d u a l p r o d u c t s w i t h i n g i v e n groups of m a t e r i a l s , an a t t e m p t w i l l be made t o b u i l d t h i s d i s c u s s i o n around l a r g e -groupings and g e n e r a l c h a r a c t e r i s -t i c s . One o f t h e p r i m a r y r e q u i r e m e n t s i n c o n s t r u c t i o n i s f o r a b u i l d -i n g m a t e r i a l c a p a b l e of s u p p o r t i n g t h e s t r u c t u r e and t h e l o a d s i t may be e x p e c t e d t o b e a r . . M a t e r i a l s commonly r e c o g n i z e d as c a p a b l e o f p e r f o r m i n g s t r u c t u r a l f u n c t i o n s a r e c o n c r e t e , s t e e l , and wood. I t i s r e c o g n i z e d t h a t t h e major advantage of s t e e l l i e s i n i t s s t r e n g t h , y e t i n h i g h - r i s e apartment c o n s t r u c t i o n , c o n c r e t e i s used a l m o s t e x c l u s i v e l y , w i t h s t e e l r o d s employed f o r r e i n f o r c i n g p u r p o s e s CMoreau and Van d e r Ryn, 1 9 6 7 ) . The l a c k o f s t e e l s u p p o r t i n g members, i n apartment b u i l d i n g s has been a t t r i b u t e d by • t h e s e a u t h o r s t o i t s r e l a t i v e l y h i g h cos,t,, and t h e f a c t t h a t s t e e l a l o n e cannot p e r f o r m f u n c t i o n s , o t h e r t h a n s t r u c t u r a l , s u p p o r t , t h u s r e q u i r i n g a d d i t i o n a l m a t e r i a l s t o p r o v i d e o t h e r needs. S t e e l f a i l s t o p r o v i d e adequate sound I n s u l a t i o n , t h e r m a l i n s u l t a i o n , w i l l c o r r o d e i f n o t a d e q u a t e l y c o a t e d , and i s n o t s u f f i c i e n t l y f i r e - r e s i s t a n t , l o s i n g s t r e n g t h r a p i d l y a t t e m p e r a t u r e s o v e r 1000*F (Moreau and Van d e r Ryn,. 1 9 6 7 ) . em C o n c r e t e p o s s e s s e s h i g h c o m p r e s s i v e s t r e n g t h , b u t i t s s t r e n g t h i n t e n s i o n i s o f t e n as l i t t l e as o n e - t e n t h i t s s t r e n g t h i n c o m p r e s s i o n ; i t i s t h e r e f o r e n o t e f f i c i e n t by i t s e l f i n r e s i s t i n g t e n s i l e and b e n d i n g s t r e s s e s (Hutcheon, 1961). Combined w i t h s t e e l r e i n f o r c e m e n t , b o t h com-p r e s s i v e and t e n s i l e s t r e n g t h r e q u i r e m e n t s can be met. S t e e l and c o n c r e t e a r e a l s o c o m p a t i b l e w i t h r e s p e c t t o t h e r m a l e x p a n s i o n s and b o t h e x h i b i t s i m i l a r s t r a i n s when l o a d e d t o t h e i r n o r m a l w o r k i n g s t r e s s e s (Hutcheon, 1961).. A t t h e same t i m e , c o n c r e t e i s c a p a b l e of p r o v i d i n g o t h e r f u n c t i o n s , p a r t i c u l a r l y f i r e r e s i s t a n c e and i n s u l a t i o n . Wood does n o t p o s s e s s the h i g h c o m p r e s s i v e s t r e n g t h o f s t e e l and c o n c r e t e (on a mass b a s i s ) , n or t h e t e n s i l e s t r e n g t h o f s t e e l and i s a c c o r d i n g l y l i m i t e d i n s t r u c t u r a l u s e s . ( I n Canada, t h e h e i g h t r e s t r i c -t i o n f o r s t r u c t u r a l wood frame c o n s t r u c t i o n i n h o u s i n g has been s e t a t t h r e e s t o r e y s by t h e N a t i o n a l B u i l d i n g Code) . Y e t wood does have good s t r e n g t h i n b o t h t e n s i o n and c o m p r e s s i o n a l o n g the g r a i n , w h i c h , combined w i t h i t s l i g h t w e i g h t , g i v e s i t a v e r y h i g h s t r e n g t h - t o - w e i g h t r a t i o ( H u t c h -eon and J e n k i n s , 1 9 6 7 a ) , h i g h e r , i n f a c t , t h a n b o t h s t e e l and c o n c r e t e . I t s a b i l i t y t o w i t h s t a n d b e n d i n g l o a d s has alw a y s c o n t r i b u t e d g r e a t l y t o i t s v a l u e as a b u i l d i n g m a t e r i a l . However, t h e r e l a t i v e l y l ow s h e a r s t r e n g t h a l o n g t h e g r a i n , n e c e s s i t a t e s c a r e f u l d e s i g n when u t i l i z i n g wood i n t e n s i o n members (Hutcheon and J e n k i n s , 1967b). U n l i k e s t e e l and c o n c r e t e , w h i c h a r e homogeneous m a t e r i a l s w i t h u n i f o r m p r o p e r t i e s t h a t can be c a l c u l a t e d i n advance, s o l i d wood i s a het e r o g e n e o u s m a t e r i a l o f g r e a t v a r i a b i l i t y (Tromp and Campredon, 1966) . T h i s w i d e range o f q u a l i t y has made n e c e s s a r y the. e s t a b l i s h m e n t o f lumber grades t o f a c i l i t a t e p r o p e r use of t h e m a t e r i a l . Softwood lumber may be e i t h e r g raded as "Yard Lumber" o r " S t r u c t u r a l Lumber." S t r u c t u r a l l y g raded m a t e r i a l i s i n t e n d e d t o meet e n g i n e e r i n g r e q u i r e m e n t s and must be c a t e g o r -i z e d by i n t e n d e d use as w e l l as s p e c i e s and grade ( D i c k e n s , 1967). I t i s seldom e c o n o m i c a l t o use t h i s t y p e o f lumber i n h o u s i n g , w i t h t h e r e s u l t t h a t t a b l e s have been p r e p a r e d showing s i z e and span r e l a t i o n s h i p s f o r y a r d g r a d e s of d i m e n s i o n lumber f o r use as j o i s t s and r a f t e r s i n h o u s i n g ( D i c k e n s , 1967). Due t o t h e i n h e r e n t v a r i a b i l i t y o f wood, most wood s t r u c -t u r e s a r e g r o s s l y o v e r - d e s i g n e d i n t h e i n t e r e s t s o f s a f e t y , and hence c o s t more t h a n t h e y s h o u l d ( M i l l i g a n , 1965). I t i s hoped t h a t t h i s can be o v e r -come w i t h m e c h a n i c a l s t r e s s g r a d i n g o f lumber i n t e n d e d f o r s t r u c t u r a l u s e . One o f the more immediate u s e s f o r m e c h a n i c a l l y s t r e s s r a t e d lumber c o u l d be i n f a c t o r y - b u i l t s t r u c t u r a l components where p e r f o r m a n c e and p r e d i c t a -b i l i t y c o u l d be e n s u r e d t h r o u g h t h e use of lumber known t o meet s p e c i f i c s t r e n g t h r e q u i r e m e n t s . I t has been p o i n t e d out by Tromp and Campredon (1966) t h a t a r c h i -t e c t s c o n s i d e r t h e r i s k s g r e a t e r when b u i l d i n g w i t h wood t h a n w i t h , i s o t r o -p i c m a t e r i a l s . F u r t h e r m o r e , a knowledge of wood i s no l o n g e r c o n s i d e r e d a p a r t o f t h e e d u c a t i o n o f a r c h i t e c t s and s t r u c t u r a l e n g i n e e r s , a f a c t o r w h i c h may be r e s p o n s i b l e f o r s h r i n k i n g m a r kets ( R i c h , 1969). These com-ments may n o t be p a r t i c u l a r l y r e l e v a n t t o t h e h o u s i n g market i n w h i c h wood frame c o n s t r u c t i o n has been used t r a d i t i o n a l l y , r e s u l t i n g i n w e l l known b u i l d i n g methods w h i c h do n o t u s u a l l y r e q u i r e e n g i n e e r i n g o r a r c h i -t e c t u r a l s e r v i c e s i n i n i t i a l d e s i g n s . P l a s t i c s a r e n o t n o r m a l l y t h ought of as s t r u c t u r a l m a t e r i a l s . They c a n be d i v i d e d i n t o two major g r o u p s : t h e r m o p l a s t i c s and t h e r m o s e t s ; t h e f o r m e r can be m e l t e d t o l i q u i d f o r m by h e a t and r e f o r m e d t o s o l i d s by c o o l i n g s w h i l e t h e l a t t e r can be formed o n l y once, by h e a t - c u r i n g , and r a t h e r t h a n l i q u i f y , w i l l e i t h e r s o f t e n and char o r b u r n when r e h e a t e d ( P l a t t s , 1 9 6 4 a ) . T h e r m o s e t t i n g p l a s t i c s o f f e r t h e b e s t p o s s i b i l i t i e s f o r s t r u c t u r a l p u r p o s e s , p a r t i c u l a r l y t h e g l a s s r e i n f o r c e d p l a s t i c s (GRP) i n w h i c h p o l y e s t e r r e s i n s a r e most commonly u s e d (Makowski, 1966) . P r o b -lems i n v o l v e d i n u s i n g p l a s t i c s s t r u c t u r a l l y a r e t h a t t h e y c r e e p under s u s t a i n e d l o a d , have an i n h e r e n t l a c k of s t i f f n e s s (Makowski, 1966), have a h i g h c o e f f i c i e n t <5f e x p a n s i o n , and t h e i r h e a t d i s t o r t i o n t e m p e r a t u r e i s g e n e r a l l y low, making them u n s u i t a b l e f o r s t r u c t u r a l use i n b u i l d i n g s ( B e n j a m i n , 1 9 6 8 ) . P r o p e r ' s t r u c t u r a l d e s i g n can overcome t h e l a c k of s t i f f s n e s s t o a l a r g e e x t e n t , b u t t h e shape and appearance of s u c h s t r u c t u r e s d i f f e r a p p r e c i a b l y from c o n v e n t i o n a l l y a c c e p t e d d e s i g n s (Makowski, 1 9 6 6 ) . P l a s t i c s a n d w i c h p a n e l s o f f e r an a d d i t i o n a l a p p l i c a t i o n o f p l a s -t i c s f o r s t r u c t u r a l p u r p o s e s . V a r i o u s expanded p l a s t i c s foams a r e f i n d -i n g a p p l i c a t i o n s as the c o r e f o r s a n d w i c h c o n s t r u c t i o n , expanded p o l y -s t y r e n e , r i g i d p o l y u r e t h a n e , . e x p a n d e d p o l y v i n y c h l o r i d e (PVC) and p h e n o l i c s b e i n g f r e q u e n t l y used t y p e s (Makowski, 1966). W i t h s k i n s of.aluminum, s t e e l , p l ywood, o r a s b e s t o s cement, t h e y p r o v i d e s t r u c t u r a l s t r e n g t h , t h e r m a l i n s u l a t i o n , and a c t as a w a t e r vapour b a r r i e r . A l t h o u g h Makowski i n d i c a t e d t h a t one and two s t o r e y b u i l d i n g s have been c o n s t r u c t e d u s i n g p l a s t i c s a n d w i c h p a n e l s as e x t e r n a l l o a d - ^ c a r r y i n g w a l l s , P l a t t s (1964a) s u g g e s t e d t h a t t h e c o s t s o f s u c h components would n o t p e r m i t s e r i o u s c o m p e t i t i o n w i t h wood frame h o u s i n g f o r some t i m e . S t r e n g t h i s o n l y one r e q u i r e m e n t o f b u i l d i n g m a t e r i a l s and i s n o t c r i t i c a l i n some a p p l i c a t i o n s . A n o t h e r major c o n s i d e r a t i o n i s t h e f i r e -r e s i s t a n c e o f t h e m a t e r i a l . The r a t e and e x t e n t o f f i r e s p r e a d t h r o u g h b u i l d i n g s i s of p r i m e i m p o r t a n c e i n f i r e p r o t e c t i o n . The f l a m m a b i l i t y o f m a t e r i a l s w i l l . d e t e r m i n e t h e ease o f i g n i t i o n and r a t e o f development o f a f i r e ( S h o r t e r , 1963). Wood has been known as a n a t u r a l f u e l f o r c e n t u r i e s , and as a, r u l e w i l l b u r n u n t i l d e s t r o y e d . I t i s now r e c o g n i z e d t h a t l a r g e t i m b e r s e c t i o n s a r e s l o w t o i g n i t e and, a l t h o u g h t h e y s u p p o r t combusion i n i t i a l l y , t h e y soon c h a r and t h e f l a m e s a r e e x t i n g u i s h e d ( M i l l i g a n , 1 9 6 5 ) . The wood w i l l c o n t i n u e t o c h a r a t a r a t e o f a p p r o x i m a t e l y 1/40 i n c h p e r m i n u t e ( G a l -b r e a t h , 1 9 6 5 ) , b u t w i l l o n l y l o s e s t r e n g t h due t o t h e r e d u c t i o n i n i t s c r o s s - s e c t i o n a l a r e a ( M i l l i g a n , 1965) . The s l o w c h a r r i n g r a t e e n a b l e s s u c h heavy s t r u c t u r a l t i m b e r s t o s u p p o r t t h e i r l o a d f o r a c o n s i d e r a b l e t i m e a f t e r the f i r e has begun, t h u s a l l o w i n g s u f f i c i e n t t i m e f o r the" b u i l d i n g t o be e v a c u a t e d and t h e f l a m e s e x t i n g u i s h e d . T h i s i s o n l y t r u e w i t h heavy t i m b e r c o n s t r u c t i o n w h i c h i s n o t u s u a l l y employed i n r e s i d e n c e s . I n common l i g h t frame c o n s t r u c t i o n , wood f r a m i n g members have a r e l a t i v e l y s h o r t f i r e endurance ( o f t e n l e s s t h a n 10 m i n u t e s ) i f exposed d i r e c t l y t o f i r e ( S h o r t e r , 1 9 6 4 ) . Wood thus has two d i s a d v a n t a g e s w i t h r e s p e c t t o f i r e r e s i s t a n c e : i t adds t o the f u e l l o a d , and can be c o m p l e t e l y d e s t r o y e d . A l t h o u g h f i r e r e t a r d a n t s a r e now a v a i l a b l e f o r t r e a t i n g wood, t h e r e are, a number of problems l i m i t i n g t h e i r u s e . These i n c l u d e l e a c h a b i l i t y ( w hich r e s t r i c t s most r e t a r d a n t t r e a t e d wood t o i n t e r i o r a p p l i c a t i o n s ) , a de-c r e a s e i n most s t r e n g t h p r o p e r t i e s of t r e a t e d m a t e r i a l , a d e c r e a s e i n t h e glvieability'; and most of a l l , t h e c o s t o f t r e a t e d wood i s h i g h . As p r e v i o u s l y i n d i c a t e d , s t e e l i s a l s o s e v e r e l y a f f e c t e d by f i r e . A t t e m p e r a t u r e s above 1000°F, s t e e l l o s e s s t r e n g t h s i g n i f i c a n t l y and i t i s t hus e s s e n t i a l t h a t s t e e l be p r o t e c t e d w i t h an i n s u l a t i n g l a y e r when used i n s t r u c t u r a l a p p l i c a t i o n s i n b u i l d i n g s (Moreau and Van der Ryn, 1967). As i n the c a s e o f l i g h t wood c o n s t r u c t i o n , l i g h t s t e e l f r a m i n g members, i f exposed d i r e c t l y t o f i r e , have s h o r t f i r e e ndurance, o f t e n l e s s t h a n 10 m i n u t e s ( S h o r t e r , 1 9 6 4 ) . B r i c k and o t h e r b u r n e d c l a y p r o d u c t s a r e r e l a t i v e l y s t a b l e m a t e r -i a l s i n f i r e , l o s i n g l i t t l e s t r e n g t h ( G a l b r e a t h , 1965). C o n c r e t e w i l l l o s e s t r e n g t h when exposed t o f i r e , r e t a i n i n g about o n e - h a l f i t s f o r i g i n a l s t r e n g t h a t 950°F and o n e - t h i r d a t 1300°F; t h e s t r e n g t h l o s s i s i r r e v e r -s i b l e . However, t h e good t h e r m a l i n s u l a t i o n p r o p e r t i e s o f c o n c r e t e , as w i t h wood, p r e v e n t s u f f i c i e n t h e a t i n g up of t h e i n t e r i o r o f c o n c r e t e members t o cause s i g n i f i c a n t s t r e n g t h r e d u c t i o n ( G a l b r e a t h , 1 9 6 5 ) . F i r e , a l o n g w i t h smoke and t o x i c fumes, i s a ma j o r p r o b l e m w i t h p l a s t i c s . I n s t r u c t u r a l a p p l i c a t i o n s , p l a s t i c s w o u l d l o s e s t r e n g t h and c o l l a p s e a t t e m p e r a t u r e s much b e l o w t h o s e r e a c h e d i n any w e l l d e v e l o p e d f i r e ( P l a t t s , 1 9 6 4 a ) , and i n s u c h a s i t u a t i o n , t h e " s e l f - e x t i n g u i s h i n g " c h a r a c t e r i s t i c s o f some p l a s t i c s have l i t t l e b e a r i n g on t h e f i r e r e s i s t -ance o f t h e ^ s t r u c t u r e s i n c e t h e c r i t i c a l q u e s t i o n i s how much time p a s s e s b e f o r e t h e s u p p o r t i n g members c o l l a p s e . There i s a c o n s i d e r a b l e v a r i a -t i o n i n t h e f l a m m a b i l i t y of d i f f e r e n t p l a s t i c s , b u t g e n e r a l l y i t i s f e l t t h a t where u s e d as n o n - s t r u c t u r a l f i n i s h e s , t r i m s and c o v e r i n g s , t h e y r e p r e s e n t a s m a l l f i r e l o a d ( P l a t t s , 1 964a). F o u r groups o f p l a s t i c s a r e p a r t i c u l a r l y t r o u b l e d by f l a m m a b i l -i t y p roblems b e c a u s e o f t h e i r g e n e r a l and w i d e s p r e a d m a r k e t s : v i n y l s and p o l y o l e f i n s , s t y r e n i c s ( m o s t l y ABS ) , p o l y e s t e r s , and foams ( m o s t l y u r e t h a n e s and expanded p o l y s t y r e n e ) (Wood, 1968). A major p r o b l e m w i t h r e t a r d a n t s d e v e l o p e d t o i n c r e a s e t h e f l a m e r e s i s t a n c e o f s u c h p l a s t i c s • i s t h a t most of the r e t a r d a n t m a t e r i a l s e i t h e r t e n d t o degrade t h e p l a s -t i c o r i n c r e a s e i t s p r o d u c t i o n o f smoke and t o x i c fumes when burned (Wood, 1968). T h i s o n l y adds t o t h e p r o b l e m o f smoke e m i s s i o n w h i c h can be h i g h , t h e r e b y r a i s i n g t h e q u e s t i o n o f p r a c t i c a l i t y i n m u l t i - s t o r e y b u i l d i n g s where e g r e s s i s d i f f i c u l t , ( P l a t t s , 1 9 6 4 a ) . Good t h e r m a l i n s u l a t i o n i s d e s i r a b l e f o r m a t e r i a l s used i n e x -t e r i o r w a l l s and r o o f s where an i m p o r t a n t f u n c t i o n i s t o i s o l a t e t h e i n -t e r i o r f r o m i n c l e m e n t e x t e r i o r c o n d i t i o n s . V e r y few r e s i d e n t i a l c o n s t r u c -t i o n m a t e r i a l s p r o v i d e s u f f i c i e n t i n s u l a t i n g v a l u e of t h e m s e l v e s , and w i t h b o t h wood frame and s o l i d masonry c o n s t r u c t i o n , i t i s common p r a c t i c e t o p l a c e i n s u l a t i o n w i t h i n t h e e x t e r i o r w a l l s ( B a l l , 1 961). The i n s u l a t i o n p r o v i d e d by t h e b a s i c w a l l s y s t e m w i l l , however, a f f e c t t he amount and c o s t of a d d i t i o n a l i n s u l a t i o n r e q u i r e d t o meet a c c e p t e d s t a n d a r d s . M e t a l s a r e t h e p o o r e s t t h e r m a l i n s u l a t o r s , hence t h e y a r e h i g h l y dependent upon o t h e r m a t e r i a l s where t h e r m a l i n s u l a t i o n i s r e q u i r e d . By c o m p a r i s o n , t h e i n s u l a t i n g p r o p e r t i e s o f most o t h e r b u i l d i n g m a t e r i a l s a r e q u i t e good. T a b l e 14 shows t h e r m a l c o n d u c t i v i t y v a l u e s f o r s e v e r a l common A t y p e o f p l a s t i c - c o m p o s e d o f a c r y l o n i t r i l e , b u t a d i e n e , and s t y r e n e . b u i l d i n g m a t e r i a l s . I t may be n o t e d t h a t wood i s a b e t t e r i n s u l a t o r t h a n b r i c k and c o n c r e t e . The foamed p l a s t i c s o f f e r e x c e l l e n t i n s u l a t i n g p r o p e r -t i e s , the u r e t h a n e s i n p a r t i c u l a r o f f e r i n g K v a l u e s about o n e - h a l f t h o s e o f c o n v e n t i o n a l i n s u l a t i o n m a t e r i a l s . I t would thus appear t h a t p l a s t i c foams have c o n s i d e r a b l e p o t e n t i a l as i n s u l a t i o n i n r e s i d e n t i a l b u i l d i n g s and may o f f e r s t i f f c o m p e t i t i o n t o g l a s s w o o l , m i n e r a l w o o l , and i n s u l a t i o n b o a r d s p r e s e n t l y i n common use. TABLE 14 THERMAL CONDUCTIVITY OF BUILDING MATERIALS MATERIAL THERMAL CONDUCTIVITY (K) [(Btu)(in.)/(sq.ft.)(°F)(hr.)]. Aluminum S t e e l C o n c r e t e , s a n d , and s t o n e a g g r e g a t e s B r i c k , common b u i l d i n g Wood, p a r a l l e l t o g r a i n ( s p . g r . 0.35 - 0.70) Gypsum b o a r d , between l a y e r s o f paper Wood, a c r o s s t h e g r a i n ( s p . g r . 0.35 - 0.70) I n s u l a t i n g b o a r d s ( s p . g r . 0.15 - 0.30) G l a s s w o o l U r e t h a n e foam 1400 315 11 - 16 4.8 1.6 - 2.9 1.4 0.65 - 1.15 0.27 - 0.32 0.27 0.16 From: P l a t t s , R. E., 1964a. The R o l e o f P l a s t i c s i n House S t r u c t u r e . S o u r c e : Stamm, A. J . , 1964. Wood and C e l l u l o s e S c i e n c e . Sound i n s u l a t i o n i s a n o t h e r d e s i r a b l e p r o p e r t y of b u i l d i n g m a t e r -i a l s : i n w a l l systems t o e x c l u d e n o i s e d i s t u r b a n c e s f r o m o u t s i d e , and i n f l o o r s and c e i l i n g s t o r e d u c e n o i s e t r a n s m i s s i o n between d w e l l i n g ^ u n i t s i n m u l t i - s t o r e y s t r u c t u r e s . L i g h t w e i g h t c o n s t r u c t i o n i n modern b u i l d i n g methods has r e q u i r e d t h a t sound a b s o r p t i o n be e x p l i c i t l y d e a l t w i t h i n t h e b a s i c d e s i g n o f w a l l s and f l o o r s (Northwood, 1960). A v a i l a b l e b u i l d i n g m a t e r i a l s as used i n s t a n d a r d wood frame and masonry c o n s t r u c t i o n do n o t p r o v i d e s u f f i c i e n t sound i n s u l a t i o n w i t h o u t a d d i t i o n a l d e s i g n c o n s i d e r -a t i o n s . I n d e t a c h e d h o u s e s , sound problems a r e a t a minimum. I n m u l t i -f a m i l y d w e l l i n g s , however, n o i s e can be a s i g n i f i c a n t p r o b l e m . I n any d i s c u s s i o n c o n c e r n i n g sound t r a n s m i s s i o n , i t i s n e c e s s a r y t o d i s t i n g u i s h between a i r b o r n e sound t r a n s m i s s i o n ( t h r o u g h w a l l s and f l o o r s ) and i m p a c t sound t r a n s m i s s i o n ( t h r o u g h f l o o r s ) . Impact n o i s e s a r e m o r e - d i f f i c u l t t o c o n t r o l . I n t h e c a s e of a i r b o r n e and i m p a ct n o i s e s , t h e f a c t o r s g o v e r n -i n g sound t r a n s m i s s i o n a r e t h e mass of t h e w a l l , i t s s t i f f n e s s , t h e c o n -t i n u i t y o f t h e t r a n s m i s s i o n p a t h , and sound a b s o r p t i o n i n t h e s p a c e i n s i d e t h e w a l l o r f l o o r (Northwood e t al., 1967). F o r sound t r a n s m i s s i o n through, w a l l s between o c c u p a n c i e s , t h e R e s i d e n t i a l S t a n d a r d s o f t h e N a t i o n a l B u i l d i n g Code (NBC), r e q u i r e a t r a n s m i s s i o n l o s s o f Sound T r a n s m i s s i o n C l a s s (STC) 45 o r h i g h e r . The most common (and p r o b a b l y s i m p l e s t ) s t u d w a l l m e e t i n g t h i s r e q u i r e m e n t i s an arrangement o f s t a g g e r e d s t u d s w i t h 1 / 2 - i n c h p l a s t e r on 3 / 8 - i n c h l a t h , o r w i t h 5 / 8 - i n c h gypsum b o a r d , w i t h m i n e r a l wool:between t h e s t u d s . I n c o m p a r i s o n , t h e s i m p l e s t masonry w a l l s a t i s f y i n g t h i s r e q u i r e m e n t i s a w a l l o f 8 - i n c h dense a g g r e g a t e b l o c k o r an 8 - i n c h . l i g h t , w e i g h t b l o c k p a i n t e d on b o t h s i d e s (Northwood et ul., 1967). - The masonry w a l l w o u l d appear t o have t h e s i m p l e s t c o n s t r u c t i o n , b u t under n o r m a l c i r c u m s t a n c e s w o u l d be f a c e d w i t h p l a s t e r o r gypsum b o a r d , p r o v i d i n g an even h i g h e r STC r a t i n g . P l a s t i c s s a n d w i c h p a n e l s , due t o t h e i r l i g h t w e i g h t and h a r d s u r -f a c e , p r o v i d e poor a c o u s t i c i n s u l a t i o n , b u t c o n t i n u i n g r e s e a r c h u s i n g m u l t i - l a y e r e d c o r e s o f h i g h and l o w " d e n s i t y foams a r r a n g e d a l t e r n a t e l y may p r o d u c e an adequate s o l u t i o n t o t h e p r o b l e m (Makowski, 1966). Impact n o i s e i s o f t e n r a t e d by t h e Impact N o i s e R a t i n g (INR) de-v e l o p e d by t h e U.S. F e d e r a l H o u s i n g A d m i n i s t r a t i o n . A l t h o u g h t h e r e a r e no r e s i d e n t i a l s t a n d a r d s r e l a t i n g t o i m pact n o i s e i n Canada, i t i s g e n e r a l l y a g r e e d t h a t f o r s a t i s f a c t o r y p e r f o r m a n c e , t h e INR s h o u l d be z e r o o r p o s i -t i v e ( O l y n y k , 1967). The r e d u c t i o n of i m p a c t n o i s e depends l a r g e l y - upon t h e d e s i g n o f t h e f l o o r s y s t e m s i n c e no commonly used s t r u c t u r a l b u i l d i n g m a t e r i a l s p o s s e s s s u f f i c i e n t i n s u l a t i n g p r o p e r t i e s on t h e i r own. F o r example, common wood frame f l o o r s (as used i n d e t a c h e d houses) have an INR of -8 t o -18, and a STC o f 47 t o 32 (Northwood et al., 1967). A 4-i n c h b a r e r e i n f o r c e d c o n c r e t e s l a b f l o o r t e s t e d by O l y n y k (1967) had an INR of -21. A l t h o u g h c o n c r e t e i s r e l a t i v e l y e f f e c t i v e i n r e d u c i n g a i r -b o r n e sound, i m p a c t n o i s e t r a n s m i s s i o n t h r o u g h c o n c r e t e s l a b i s a p r o b l e m i n a partments (Moreau and Van d e r Ryn, 1 9 6 7 ) . The use o f a s o f t f l o o r c o v e r i n g s u c h as a c a r p e t i s t h e most e f f e c t i v e method of r e d u c i n g impact n o i s e s . R e s i l i e n t c o v e r i n g s s u c h as v i n y l , l i n o l e u m o r r u b b e r t i l e a r e of l i t t l e v a l u e i n c o n t r o l l i n g i m p a c t n o i s e (Northwood et al.,. 1967). These a u t h o r s d e s c r i b e o t h e r methods o f c o n t r o l l i n g i m p a c t n o i s e w h i c h i n c l u d e p r o v i d i n g a f l o a t i n g f l o o r ( u s i n g a r e s i l i e n t l a y e r such as f i b r e -b o a r d ) , p r o v i d i n g a suspended c e l l i n g , and p l a c i n g m i n e r a l w o o l i n s u l a t i o n between t h e f l o o r and c e i l i n g . S t e e l p r e s e n t s poor a c o u s t i c a l c h a r a c t e r i s t i c s b o t h f o r a i r b o r n e and i m p a ct n o i s e s and w o u l d r e q u i r e e l a b o r a t e systems of s o u n d - p r o o f i n g b e f o r e becoming a c c e p t a b l e (Moreau and Van der Ryn, 1967). I t would appear t h a t t h e a c o u s t i c p r o p e r t i e s o f s t r u c t u r a l m a t e r -i a l s , a l t h o u g h i m p o r t a n t , do n o t p l a y a s i g n i f i c a n t p a r t i n t h e c h o i c e o f s u c h m a t e r i a l s , s i n c e s t r u c t u r a l p e r f o r m a n c e and f i r e r e s i s t a n c e a r e g i v e n p r i m e c o n s i d e r a t i o n . However, a c o u s t i c p r o p e r t i e s a r e i m p o r t a n t i n c h o o s -i n g f i n i s h e d f l o o r i n g m a t e r i a l s and m a t e r i a l s used i n f l o a t i n g f l o o r s atid h a n g i n g c e i l i n g s . Some impact n o i s e r a t i n g s o b t a i n e d by O l y n y k f o r v a r -i o u s f l o o r c o n s t r u c t i o n s u s e d on a 4 - i n c h r e i n f o r c e d c o n c r e t e s l a b a r e shown i n T a b l e 15. S e v e r a l m a t e r i a l s i n c l u d i n g f i b r e b o a r d s , c o r k b o a r d , v a r i o u s expanded p l a s t i c foams, and c a r p e t i n g a l l p o s s e s s good a c o u s t i c a l p r o p e r t i e s i n f l o o r c o n s t r u c t i o n s , and t h e i r a b i l i t y t o compete w i l l l a r g e -l y depend on t h e i r r e l a t i v e p r i c e s and t h e t o t a l i n - p l a c e c o s t of t h e f l o o r s y s t e m i n w h i c h t h e y a r e used. I t may be n o t e d i n T a b l e 15 t h a t t h e v i s c o s e c a r p e t p r o v i d e s the h i g h e s t INR and i s a l s o t h e s i m p l e s t s u r f a c e c o n s t r u c -t i o n . A n o t h e r c o n s i d e r a t i o n i n c h o o s i n g a p p r o p r i a t e m a t e r i a l s i s t h e i r d u r a b i l i t y under the c o n d i t i o n s of use. M a t e r i a l s r e q u i r i n g f r e q u e n t m a i n -t e n a n c e a r e i n a p o o r e r c o m p e t i t i v e p o s i t i o n t h a n t h o s e w h i c h a r e v i r t u a l l y m a i n t e n a n c e f r e e . I n e x t e r i o r a p p l i c a t i o n s , c l i m a t i c f a c t o r s and n a t u r a l phenomena a r e r e s p o n s i b l e f o r most of t h e d e t e r i o r a t i o n t h a t o c c u r s i n b u i l d i n g m a t e r i a l s . IMPACT NOISE RATINGS USING VARIOUS FLOOR CONSTRUCTIONS ON CONCRETE FLOOR CONSTRUCTION IMPACT NOISE RATING 1 / 8 - i n . v i n y l - a s b e s t o s t i l e bonded t o 1 / 4 - i n . plywood on 1 / 2 - i n . plywood on 1 / 2 - i n . f i b r e b o a r d ( d e n s i t y = 16.9 l b . / c u . f t . ) on b . c . + 5 1 / 8 - i n . v i n y l - a s b e s t o s t i l e bonded t o 1 / 4 - i n , plywood on 5 / 8 - i n . plywood bonded t o 1 / 4 - i n . r e g u l a r f l e x i b l e p o l y u r e t h a n e foam ( d e n s i t y = 1 . 4 l b . / c u . f t . ) on b . c . + 2 1 - 3 / 8 - i n . p r e c a s t c o n c r e t e on 1 / 4 - i n . f i b r e b o a r d ( d e n s i t y = 19 l b . / c u . f t . ) on b . c . 0 1 - 3 / 8 - i n . p r e c a s t c o n c r e t e on 1 - i n . c o r k b o a r d ( d e n s i t y = 7.9 l b . / c u . f t . ) on b . c . + 5 1 - 3 / 8 - i n . p r e c a s t c o n c r e t e on 5 / 8 - i n . gypsum w a l l b o a r d ( d e n s i t y =.49 l b . / c u . f t . ) on b.c. - 1 1 - 3 / 8 - i n . p r e c a s t c o n c r e t e on 1 - i n . s e m i - r i g i d expanded p o l y u r e t h a n e ( d e n s i t y = 1.9 l b . / c u . f t . ) on b . c . + 6 V i s c o s e c a r p e t w i t h 1 / 4 - i n . l o o p p i l e , c o a t e d back ( s u r f a c e d e n s i t y = 0.35 l b . / c u . f t . ) on b . c. +13 4 - i n . b a r e c o n c r e t e s l a b S o u r c e : O l y n y k , D., 1967. Impact Sound T r a n s m i s s i o n T e s t s on a C o n c r e t e S l a b F l o o r w i t h V a r i o u s S u r f a c e C o n s t r u c t i o n s . Most m a t e r i a l s a r e s u b j e c t t o some t y p e o f w e a t h e r i n g o r c o r r o s i o n , f o r w h i c h t h e p r e s e n c e o f w a t e r i s o f t e n a r e q u i r e m e n t . W i t h m e t a l s t h e r e I s a p r o b l e m of c o r r o s i o n ( f o r w h i c h w a t e r i s n e c e s s a r y ) , a major r e a s o n why t h e r e has been l i m i t e d use of m e t a l c u r t a i n w a l l s i n apartment c o n s t r u c t i o n (Moreau and Van der Ryn, 1967). I r o n and . s t e e l have no monopoly on c o r r o s i o n p r o b l e m s . Water r u n n i n g o v e r copper and aluminum can a l s o r e s u l t i n d i s f i g u r i n g marks and s t r e a k s on e x t e r i o r s u r f a c e s , s u c h as below aluminum window frames ( L a t t a , 1 9 6 2 ) . Recent a d -vances i n p l a s t i c c o a t i n g s , baked enamel f i n i s h e s , , a n d o t h e r p r o t e c t i v e c o a t i n g s have c o n t r i b u t e d much t o t h e s o l u t i o n o f t h e s e p r o b l e m s . M a t e r i a l s s u c h as c o n c r e t e and porous s t o n e s c a n . s u f f e r damage fr o m a number o f c a u s e s . S a l t s may be d i s s o l v e d by f r e e w a t e r i n t h e p o r e s of t h e m a t e r i a l , c a r r i e d t o t h e s u r f a c e and d e p o s i t e d t h e r e l e a v i n g a s t a i n c a l l e d e f f l o r e s c e n c e ( S e r e d a , 1969). I f w a t e r i s p r e s e n t i n t h e v o i d s o f s u c h m a t e r i a l s s u c h t h a t t h e m a t e r i a l i s n e a r l y s a t u r a t e d , f r e e z i n g o f the w a t e r can r e s u l t i n s u f f i c i e n t l y h i g h f o r c e s t o r u p t u r e i t ( L a t t a , 1962). S u l p h a t e a t t a c k on c o n c r e t e and t h e w e a t h e r i n g o f s t o n e and m o r t a r by r a i n w a t e r a c i d i f i e d by s u l p h u r gases i n t h e a i r a r e a d d i t i o n a l examples o f de-g r a d a t i o n ( S e r e d a , 1 9 6 9 ). B a s i c a l l y , however, s u c h m a t e r i a l s a r e r e g a r d e d as b e i n g a l m o s t m a i n t e n a n c e — f r e e (Benson, 1968a). Wood i s a d u r a b l e m a t e r i a l and w i l l r e m a i n i n t a c t o v e r l o n g p e r -i o d s w i t h o u t t h e use of c o a t i n g s ; b u t w e a t h e r i n g e f f e c t s do r e s u l t i n a change o f appearance o f t h e exposed s u r f a c e ( A s h t o n , 1 9 67). R a p i d m o i s t u r e c o n t e n t changes due t o w e t t i n g and d r y i n g o f exposed s u r f a c e s can r e s u l t i n s e r i o u s c h e c k i n g as w e l l . E x t e r i o r wood s u r f a c e s a r e t h u s n o r m a l l y c o a t e d i n o r d e r t o improve t h e appearance.. C o n c e n t r a t i o n s o f m o i s t u r e a t t h e i n -t e r f a c e between t h e wood and p a i n t o f t e n cause b l i s t e r s and f a i l u r e o f t h e p a i n t s u r f a c e . B l e e d t h r o u g h o f k n o t s has a l s o been a common p r o b l e m ( A s h -t o n , 1 9 6 7 ) . Depending on t h e t y p e of c o a t i n g u s e d , w o o d ' s u r f a c e s n o r m a l l y < r e q u i r e r e p a i n t i n g at r e g u l a r i n t e r v a l s . o f about one t o f o u r o r f i v e y e a r s . The need f o r f r e q u e n t m a i n t e n a n c e of wood s u r f a c e s i n e x t e r i o r c o n d i t i o n s i s a s i g n i f i c a n t f a c t o r i n n o t c h o o s i n g s u c h m a t e r i a l f o r s i d i n g (Benson, 1968a) and a l s o f o r s o f f i t s , f a s c i a , and t r i m . A l t h o u g h many p l a s t i c s s u f f e r from c r a z i n g ( c r a c k i n g on a s m a l l s c a l e ) and f a d i n g due t o e x p o s u r e t o u l t r a v i o l e t l i g h t ( A s h t o n , 1 9 6 9 ) , some p l a s t i c f i l m s have been d e v e l o p e d w h i c h can r e t a i n t h e i r r e s i l i e n c e and appearance i n d e f i n i t e l y ( P l a t t s , 1964a).. C h l o r o s u l p h o n a t e d p o l y e t h y -l e n e ("Hypalon") and p o l y v i n y l f l u o r i d e ( " T e d l a r " ) a r e two of t h e most im-p o r t a n t s u c h c o a t i n g s y e t d e v e l o p e d , and can be used on a v a r i e t y o f s u r -f a c e s i n c l u d i n g m e t a l s and wood ( P l a t t s , 1 964a). These w i l l u n d o u b t e d l y i n f l u e n c e a movement toward m a i n t e n a n c e - f r e e s u r f a c e s p r o v i d e d t h a t t h e c o s t s a r e r e a s o n a b l e . R o t t i n g i s a n o t h e r p r o b l e m f a c e d by wood b u t n o t by i t s c o m p e t i -t o r s . Dry r o t , caused by Porta incrassata, i s t h e main decay fungus a c t i v e i n d w e l l i n g s i n N o r t h .America, although a few o t h e r brown r o t s a r e a l s o f o und (Boyce, 1 9 3 8 ) . Decay i n houses i s l a r g e l y p r e v e n t a b l e and r e s u l t s i n t h e f i r s t p l a c e from f a u l t y d e s i g n , f a u l t y c o n s t r u c t i o n , t h e use of wet t i m b e r , o r l a c k o f s a n i t a r y c o n d i t i o n s a f t e r c o n s t r u c t i o n . W i t h t h e knowledge o f t h e s e f u n g i w h i c h now e x i s t s , and t h e a v a i l a b i l i t y of a num-, b e r o f p r e s e r v a t i v e s , t h e r e i s no r e a s o n why decay s h o u l d c o n t i n u e t o be a p r o b l e m w i t h wood. The above d i s c u s s i o n has t o uched on a e s t h e t i c c o n s i d e r a t i o n s o f . m a t e r i a l s i n c o n n e c t i o n w i t h w e a t h e r i n g . I t may a l s o be n o t e d t h a t n a t u r a l m a t e r i a l s , p a r t i c u l a r l y wood, have an a e s t h e t i c a p p e a l n o t p r e s e n t i n s y n -t h e s i z e d m a t e r i a l s . A c c o r d i n g t o Tromp and Campredon ( 1 9 6 6 ) , s e v e r a l s t u d i e s have i n d i c a t e d t h a t wood i n t h e home environment i n c r e a s e s t h e f e e l i n g . o f w e l l b e i n g . I n s u p p o r t o f t h i s , Blomgren.(1965) s t a t e d t h a t wood has a number of b a s i c a p p e a l s and i s a s s o c i a t e d w i t h s e c u r i t y , p e a c e f u l n e s s , and r e l a x a t i o n . A u n i q u e advantage o f the a e s t h e t i c q u a l -i t i e s o f wood i s t h e w i d e range of d i s t i n c t i v e i n d i v i d u a l i t y t h a t wood p r o d u c t s can assume. The advantage of wood from an a e s t h e t i c v i e w p o i n t i n i n t e r i o r d e c o r a t i n g i s s u p p o r t e d by a t t e m p t s made t o emulate i t u s i n g o t h e r m a t e r i a l s , n o t a b l y p l a s t i c l a m i n a t e s (Tromp and Campredon, 1966). A v a r i e t y o f p r o d u c t s a r e now a v a i l a b l e w h i c h do a r e m a r k a b l y good j o b of s i m u l a t i n g wood g r a i n p a t t e r n and c o l o u r . B u i l d i n g Codes The manner and e x t e n t t o which, b u i l d i n g codes i n f l u e n c e m a t e r i a l s . u s e , a l t h o u g h sometimes c l e a r , i s n o t always e v i d e n t . D i r e c t code r e s t r i c -t i o n s w h i c h p r e v e n t t h e use of s p e c i f i c m a t e r i a l s a r e t h e e a s i e s t t o a p p r e -c i a t e . Code r e g u l a t i o n s b a s i c a l l y r e s t on t h e c r i t e r i o n o f p u b l i c s a f e t y w h i c h r e q u i r e s s t r u c t u r a l s u f f i c i e n c y , p r o p e r f i r e p r e v e n t i o n measures, and p r o v i s i o n s f o r p u b l i c h e a l t h . Wood, b e i n g c o m b u s t i b l e , has been w i d e l y r e s t r i c t e d by b u i l d i n g codes and, a c c o r d i n g t o t h e N a t i o n a l F o r e s t P r o d u c t s A s s o c i a t i o n ( c a . 1965), has been more c l o s e l y c o n t r o l l e d t h a n any o t h e r m a t e r i a l . M a n u f a c t u r e r s o f o t h e r m a t e r i a l s have a l s o c l a i m e d undue r e s t r i c -t i o n s due t o b u i l d i n g r e g u l a t i o n s . D o e r i n g (1967) i n d i c a t e d t h a t s t e e l s t i l l f a c e s a n c i e n t r e s t r i c t i o n s and a e s t h e t i c i n h i b i t i o n s . S i m i l a r l y , t h e pr o p o s e d r e v i s i o n s t o t h e N a t i o n a l B u i l d i n g Code o u t l i n e d by Solomon ( 1 9 6 9 ) , w h i c h c a l l f o r t h e use o f b u i l d i n g m a t e r i a l s h a v i n g fewer smoke-producing q u a l i t i e s , w i l l have t h e g r e a t e s t e f f e c t on the p l a s t i c s i n d u s t r y . R e q u i r e m e n t s w h i c h c a l l f o r n o n c o m b u s t i b l e c o n s t r u c t i o n e x c l u d e wood'and l e s s o b v i o u s r u l e s may a l s o r e s u l t i n l i m i t a t i o n s on i t s u s e . As l o n g as s u c h r e g u l a t i o n s a r e j u s t i f i e d , t h e y cannot be r a t i o n a l l y opposed. I n s u c h c a s e s , t h e o n l y a l t e r n a t i v e i s t o p u r s u e f u r t h e r r e s e a r c h on f i r e r e t a r d a n t s t o l o w e r t h e i r c o s t and e l i m i n a t e o t h e r problems r e l a t e d t o t h e i r u s e , o r combine o t h e r m a t e r i a l s w i t h wood t o meet f i r e code a p p r o v a l . A c c o r d i n g t o McCance (1969a)-, d i s c r i m i n a t i o n a g a i n s t wood i s p r a c t i c e d i n many of our l a r g e s t c i t i e s i n an e f f o r t t o i n c r e a s e f i r e s a f e t y . Where s u c h p r a c t i c e s a r e e x c e s s i v e , t h e o n l y r e s u l t i s t o i n c r e a s e b u i l d i n g c o s t s w i t h o u t t h e b e n e f i t s o f added s a f e t y . O p p o s i t i o n by n a t i o n a l o r r e g i o n a l f o r e s t p r o d u c t s a s s o c i a t i o n s s h o u l d be made i n s u c h i n s t a n c e s . A major p r o b l e m f a c i n g t h e r e s i d e n t i a l c o n s t r u c t i o n i n d u s t r y i n Canada i s t h e m u l t i p l i c i t y o f b u i l d i n g codes w h i c h a r e o f t e n c o n t r a d i c -t o r y and u n n e c e s s a r i l y r e s t r i c t i v e (Fowke, 1969a). T h i s has r e s u l t e d from the d e l e g a t i o n o f a u t h o r i t y f o r b u i l d i n g r e g u l a t i o n s t o m u n i c i p a l i t i e s w h i c h o f t e n l a c k t h e c a p a b i l i t y o f p r o d u c i n g and a d m i n i s t e r i n g a r e a l i s t i c code. The l a c k o f u n i f o r m i t y i n codes has been c i t e d as t h e g r e a t e s t h i n d r a n c e t o t h e u t i l i z a t i o n o f new b u i l d i n g m a t e r i a l s and t e c h n i q u e s . ; A degr e e o f u n i f o r m i t y has been a t t a i n e d t h r o u g h the N a t i o n a l B u i l d i n g Code (NBC), an a d v i s o r y document p u b l i s h e d under t h e a u t h o r i t y o f t h e A s s o c i a t e Committee on t h e N a t i o n a l B u i l d i n g Code o f t h e N a t i o n a l Re-s e a r c h C o u n c i l ( L e g g e t , 1 9 6 7 ) . A c c o r d i n g t o L e g g e t , a t t h e end o f 1966 ov e r 70 p e r c e n t o f t h e Ca n a d i a n u r b a n p o p u l a t i o n l i v e d i n m u n i c i p a l i t i e s u s i n g t h e NBC i n w h o l e o r i n p a r t , w h i l e o v e r 90 p e r c e n t o f t h e i n c o r -p o r a t e d c i t i e s had adopted i t . However, i t i s th o u g h t t h a t i n . t h e m a j o r i t y of c a s e s where t h e NBC has been a l t e r e d f o r . u s e by m u n i c i p a l i t i e s , t h e a l t e r e d v e r s i o n b e a r s l i t t l e r e s e m b l a n c e t o t h e o r i g i n a l (Plywood W o r l d , 1968). The i d e a o f a t r u l y u n i f o r m b u i l d i n g code t h r o u g h o u t Canada i s s u p p o r t e d by e v e r y p r o f e s s i o n a l and t r a d e a s s o c i a t i o n d i r e c t l y o r i n d i r e c t -l y c o n n e c t e d w i t h c o n s t r u c t i o n , i n c l u d i n g a r c h i t e c t s , e n g i n e e r s , c o n t r a c -t o r s ; h o m e b u i l d e r s , and m a n u f a c t u r e r s / ( P l y w o o d W o r l d , 1968). Support o f t h i s o b j e c t i v e i s a l s o f o r t h c o m i n g from s u c h o r g a n i z a t i o n s as t h e N a t i o n a l R e s e a r c h C o u n c i l , t h e A s s o c i a t i o n o f C a n a d i a n F i r e M a r s h a l l s , and t h e Cana-d i a n U n d e r w r i t e r s A s s o c i a t i o n , t o name a few. W i t h i n c r e a s i n g p r e s s u r e f o r a u n i f o r m code, i t i s a n t i c i p a t e d t h a t t h e 1970 NBC w i l l r e c e i v e g r e a t e r a c c e p t a n c e by m u n i c i p a l i t i e s ( F i n . P o s t , 1969b). The r e l e v a n t q u e s t i o n f o r t h e f o r e s t i n d u s t r i e s i s : how w i l l a u n i f o r m b u i l d i n g code i n f l u e n c e wood consumption i n d w e l l i n g s ? I t may a c t t o e l i m i n a t e e x c e s s i v e f i r e r e s t r i c t i o n s on c o m b u s t i b l e m a t e r i a l s w h i c h would be of d e f i n i t e advantage t o wood p r o d u c t s m a n u f a c t u r e r s . I f u n i f o r m -i t y promotes t h e a c c e p t a n c e o f s u i t a b l e new m a t e r i a l s and t e c h n i q u e s as i s c l a i m e d , t h e n i t w i l l f a v o u r t h e i n n o v a t o r s i n t h i s t r a d i t i o n a l i n d u s t r y . I f i n d u s t r i a l R & D e x p e n d i t u r e s as p r e v i o u s l y o u t l i n e d a r e an i n d i c a t i o n o f i n n o v a t i v e p r o w e s s , t h e n s u b s t i t u t e s f o r wood c o u l d be e x p e c t e d t o e n t e r t h e h o u s i n g market a t a f a s t e r r a t e . A n o t h e r i m p l i c a t i o n of u n i f o r m b u i l d -i n g codes i s t h a t i t w i l l f a c i l i t a t e i n d u s t r i a l i z e d b u i l d i n g by. making t h e p r o d u c t s o f . a n y g i v e n f a c t o r y a c c e p t a b l e i n a l l m u n i c i p a l i t i e s . The que s -t i o n o f t h e i n f l u e n c e o f i n d u s t r i a l i z e d b u i l d i n g on the f o r e s t p r o d u c t s i n -d u s t r i e s w i l l be d e a l t w i t h i n a subsequent s e c t i o n . P r e f e r e n c e s P r e f e r e n c e s o f c u s t o m e r s , b u i l d e r s , a r c h i t e c t s and e n g i n e e r s p l a y a p a r t i n m a t e r i a l s c h o i c e ? These p r e f e r e n c e s a r e n o r m a l l y based on t h e c h a r a c t e r i s t i c s of t h e a l t e r n a t i v e m a t e r i a l s and a d e s i r e f o r s p e c i f i c q u a l i t i e s t o be b u i l t i n t o t h e s t r u c t u r e . The c h a r a c t e r i s t i c s of m a t e r -i a l s w h i c h i n l a r g e p a r t d e t e r m i n e p r e f e r e n c e s have been d i s c u s s e d , b u t t h e w e i g h t g i v e n them i s much l e s s c l e a r . A c c o r d i n g t o R i c h ( 1 9 6 6 ) , v e r y l i t t l e has been done by t h e f o r e s t i n d u s t r i e s i n consumer r e s e a r c h , most of t h e s t u d i e s h a v i n g been c a r r i e d out by t r a d e a s s o c i a t i o n s and one o r two l a r g e companies. The i n t e r e s t of t h e wood i n d u s t r i e s i n s u c h market r e s e a r c h has been g r o w i n g i n t h e p a s t few y e a r s as e v i d e n c e d by t h e i n -c r e a s i n g volume o f l i t e r a t u r e , b u t i n f o r m a t i o n c o n c e r n i n g consumer p r e f e r -ences i s s t i l l s c a r c e . As one b u i l d e r summed i t up, t h e lumber i n d u s t r y d o e s n ' t a p p r e c i a t e how i t s p r o d u c t s a r e u s e d , d o e s n ' t know t h e b a s i c m o t i -v a t i o n s of t h e b u i l d e r o r h i s p r o b l e m s , doesn't t a l k t h e same terms as t h e b u i l d e r , and has poor c o n t a c t w i t h the b u i l d i n g i n d u s t r y ( R i c h , 1 9 6 5 ) . P r o p e r l y d i r e c t e d market r e s e a r c h i s c a p a b l e o f r e v e a l i n g consumer needs and m o t i v a t i o n s , thus p r o v i d i n g v a l u a b l e i n f o r m a t i o n f o r t h e d e s i g n of p r o d u c t s and f o r p r o m o t i o n a l a p p e a l s . A n o t h e r r e l e v a n t q u e s t i o n i s t h e degree o f i n f l u e n c e w h i c h v a r -i o u s groups e x e r t on f i n a l m a t e r i a l s c h o i c e . I n s i n g l e — f a m i l y house b u i l d -i n g , t h e c o n t r o l o f t h e a r c h i t e c t i s r e l a t i v e l y s m a l l , b e i n g l a r g e l y con-f i n e d t o custom, b u i l t houses (Fowke, 1969b). I n a r e c e n t s u r v e y made by " C a n a d i a n B u i l d e r " , b u i l d e r s were asked what p r o p o r t i o n of t h e i r p r o j e c t s were c a r r i e d out w i t h o u t a r c h i t e c t u r a l s e r v i c e s . I t was found t h a t 83 p e r c e n t o f house c o n s t r u c t i o n ' and 41 p e r c e n t o f apartment c o n s t r u c t i o n was done w i t h o u t t h e s e r v i c e s o f an a r c h i t e c t (Fowke, 1969b). I n . h i g h j r i s e a p a r t m e n t s , s t r u c t u r a l e n g i n e e r s a r e a l s o a major p a r t o f t h e d e s i g n team." Because t h e s t u d y o f wood i s i n s i g n i f i c a n t i n t h e e d u c a t i o n o f a r c h i t e c t s and e n g i n e e r s ( R i c h , 1 9 6 9 ) , t h e r e would appear t o be a need t o p r o v i d e them w i t h e d u c a t i o n a l , f a c t u a l , and p r o m o t i o n a l l i t e r a t u r e r e l a t i n g t o wood p r o d u c t s as w e l l as t o make a g r e a t e r e f f o r t i n d e t e r -m i n i n g t h e i r needs. A n o t h e r p r o f e s s i o n a l t h a t s h o u l d be m e n t i o n e d i s t h e s p e c i f i c a -t i o n w r i t e r ,. an i n d i v i d u a l who e v o l v e d out of t h e need f o r s p e c i a l i s t s who s t u d y and become f a m i l i a r w i t h m a t e r i a l s and c o n s t r u c t i o n t e c h n i q u e s ( C a n a d i a n B u i l d e r , 1969a). S i n c e t h e i r d u t i e s a r e p r i m a r i l y t o d e t e r m i n e p r o d u c t s and m a t e r i a l s t o comply w i t h any given5;performance c r i t e r i a , t he i m p o r t a n c e o f p r o v i d i n g t h i s group w i t h f a c t u a l i n f o r m a t i o n on new wood p r o d u c t s . i s o b v i o u s . Whereas t h e a r c h i t e c t , engineer,, and s p e c i f i c a t i o n w r i t e r a a r . e ^ h i g h l y i m p o r t a n t i n apartment c o n s t r u c t i o n , b u i l d e r s and consumers a r e most i m p o r t a n t i n c h o o s i n g m a t e r i a l s i n house c o n s t r u c t i o n . A r e c e n t s u r v e y i n d i c a t e d t h a t a h i g h p e r c e n t a g e o f b u i l d i n g c o n t r a c t o r s have a moderate t o h i g h degree o f i n f l u e n c e on t h e f i n a l c h o i c e o f p r o d u c t s (Fowke, 1969b), p a r t i c u l a r l y f o r s t r u c t u r a l m a t e r i a l s , f l o o r i n g , and doors and windows. However, i t may a l s o be n o t e d t h a t b u i l d e r s r e f l e c t t o a; l a r g e e x t e n t t h e p r e f e r e n c e s o f t h e i r c u s t o m e r s . E v i d e n c e s u p p o r t i n g t h i s has been f o u n d by Prestemon (1970a) i n an e x p l o r a t o r y s t u d y i n Iowa. Zaremba (1963) a l s o f ound t h a t , w i t h r e s p e c t t o m a t e r i a l s used on house e x t e r i o r s , t h e r e was a high, c o r r e l a t i o n between consumer p r e f e r e n c e and a c t u a l o w n e r s h i p . T h i s appears t o emphasize t h e f a c t t h a t i n t h e p u r c h a s e of a house, w h i c h r e p r e s e n t s an o c c a s i o n a l p u r c h a s e (sometimes o n l y once i n a p e r s o n ' s l i f e t i m e ) , t h e b u y e r i s more d e t e r m i n e d t o f u l f i l l h i s de-s i r e s f o r p a r t i c u l a r m a t e r i a l s . C o r p o r a t e L i n k s The e x i s t e n c e o f c l o s e t i e s between m a n u f a c t u r e r s and b u i l d e r s i s a s o u r c e o f i n f l u e n c e w h i c h has been g r o w i n g s t r o n g l y i n t h e U n i t e d S t a t e s i n r e c e n t y e a r s , b u t i s n o t y e t of g r e a t s i g n i f i c a n c e i n Canada. I n t h e U n i t e d S t a t e s many l a r g e b u i l d e r s have been a c q u i r e d b y c o r p o r a t i o n s l o o k i n g f o r a g u a r a n t e e d market f o r t h e i r b u i l d i n g m a t e r i a l s , and/or as a means of d i v e r s i f i c a t i o n and e x p a n s i o n . V e r t i c a l i n t e g r a t i o n , however, a c c o u n t s f o r o n l y a s m a l l amount o f t h e t o t a l f l o w o f m a t e r i a l s and p r o d u c t s s i n c e any one f i r m o n l y p r o d u ces a l i m i t e d s h a r e o f b u i l d i n g m a t e r i a l s needs ( B u i l d i n g M a t e r i a l s M e r c h a n d i s e r , 1967a); Other manufac-t u r e r s have chosen t o p r o v i d e f i n a n c i a l a s s i s t a n c e f o r s e l e c t e d b u i l d e r s o r b u i l d i n g o p e r a t i o n s . I n t h e p a s t , a number o f l a r g e c o r p o r a t i o n s have f a i l e d i n t h e i r a t t e m p t s t o e n t e r t h e b u i l d i n g i n d u s t r y , i n c l u d i n g A l l i e d C h e m i c a l C o r p o r -a t i o n , Monsanto Company, U.S. S t e e l C o r p o r a t i o n , Aluminum Company o f A m e r i c a ( A l c o a ) , U n i o n C a r b i d e C o r p o r a t i o n , and Rey n o l d s M e t a l s Company ( B u s i n e s s Week, 1967). Many of t h e i r p r oblems stemmed f r o m a t t e m p t i n g t o become b u i l d e r s t h e m s e l v e s , w i t h t h e r e s u l t t h a t most companies now e n t e r i n g t h e f i e l d a r e u t i l i z i n g t h e e x p e r t i s e o f e s t a b l i s h e d b u i l d e r s , e i t h e r t h r o u g h a c q u i s i t i o n o r j o i n t v e n t u r e s . A number of A m e r i c a n f o r e s t p r o d u c t s companies have been a c t i v e i n t h i s a r e a . U.S. Plywood-Champion P a p e r s I n c o r p o r a t e d has p a r t i c i p a t e d w i t h t h e J i m W a l t e r C o r p o r a t i o n i n a j o i n t . v e n t u r e , and t h r o u g h I t s w h o l l y owned s u b s i d i a r y Lewers & Cooke Development C o r p o r a t i o n , has p a r t i c i p a t e d i n j o i n t p r o j e c t s i n H a w a i i and on t h e m a i n l a n d ( B u s i n e s s Week, 1967). The.company has a l s o a c q u i r e d m a n u f a c t u r e r s o f wooden d o o r s , k i t c h e n c a b -i n e t s , and D r e x e l E n t e r p r i s e s , a l a r g e f u r n i t u r e m a n u f a c t u r e r (B.C. Re-s e a r c h , 1968). B o i s e Cascade C o r p o r a t i o n i s a c t i v e i n the a r e a of l i g h t c o n -s t r u c t i o n and l a n d development. T h i s company pfroduces m a n u f a c t u r e d houses t h r o u g h i t s s u b s i d i a r y K i n g s b e r r y Homes, and m o b i l e homes t h r o u g h Divco-Wayne C o r p o r a t i o n , a n o t h e r of i t s a c q u i s i t i o n s (B.C. R e s e a r c h , 1968). J o i n t h o u s e b u i l d i n g v e n t u r e s have a l s o been c a r r i e d o u t w i t h R. A. Watt Company, and P e r m a - B i l t E n t e r p r i s e s ; R. A. Watt i s now a s u b s i d i a r y of B o i s e Cascade ( T a y l o r , 1 9 6 9 ) . Evans P r o d u c t s Company i s p a r t i c i p a t i n g i n house c o n s t r u c t i o n t h r o u g h i t s Capp-Homes D i v i s i o n w h i c h p r e c u t s and s e l l s houses t h r o u g h -out most of t h e U n i t e d S t a t e s (B.C. R e s e a r c h , 1 9 6 8 ) . A c c o r d i n g t o t h e same a u t h o r i t y , P o t l a t c h F o r e s t s I n c o r p o r a t e d s u p p l i e s custom-made compo-n e n t s t o house b u i l d e r s t h r o u g h i t s Component F a b r i c a t i n g C e n t r e . The Weyerhaeuser Company, by w o r k i n g c l o s e l y w i t h s e l e c t e d f r a n -c h i s e d d e a l e r - b u i l d e r s t h r o u g h i t s R e g i s t e r e d Home Program, has a l s o moved i n t o t h e h o u s i n g f i e l d ( R i c h , 1 9 6 6 ) . Many n o n - f o r e s t p r o d u c t companies a r e a l s o becoming, a c t i v e I n house b u i l d i n g . A l c o a has p a r t i c i p a t e d i n a number of p r o j e c t s s i n c e i t s i n i t i a l f a i l u r e s , and Wes t i n g h o u s e E l e c t r i c C o r p o r a t i o n has been d e v e l o p -i n g a community i n F l o r i d a ( B u s i n e s s Week,. 1967) . • The G e n e r a l E l e c t r i c Company has l o n g range p l a n s f o r a town development, and Goodyear Rubber Company announced t h e development o f a new c i t y i n A r i z o n a ( B u i l d i n g M a t e r i a l s M e r c h a n d i s e r , 1967a). S e v e r a l o t h e r major U.S. c o r p o r a t i o n s a r e e i t h e r o p e r a t i n g , b u i l d i n g , o r p l a n n i n g t o b u i l d p l a n t s t o pro d u c e s e c t i o n a l h o u s i n g , i n c l u d i n g : O c c i d e n t a l P e t r o l e u m C o r p o r a t i o n , I n t e r -n a t i o n a l Telephone & T e l e g r a p h C o r p o r a t i o n , A m e r i c a n S t a n d a r d I n c o r p o r -a t e d , and Penn C e n t r a l Company ( F i n a n c i a l P o s t , 1970a). W i t h few e x c e p t i o n s , t h i s movement i n t o r e s i d e n t i a l c o n s t r u c -t i o n by m a j o r m a n u f a c t u r e r s has n o t been p a r a l l e l e d i n Canada.- F a i r -c h i l d A i r c r a f t a t t e m p t e d t o b u i l d m a n u f a c t u r e d homes i n M o n t r e a l f o r a s h o r t p e r i o d . b u t d i s c o n t i n u e d p r o d u c t i o n i n 1947 ( F i n a n c i a l P o s t , 1970a). G e n e r a l M o t o r s C o r p o r a t i o n has i n v e s t i g a t e d f a c t o r y - b u i l t h o u s i n g p e r i o d -i c a l l y o v e r t h e p a s t 40 y e a r s and has up t o now d e c i d e d a g a i n s t e n t r y . The Aluminum Company of-Canada ( A l c a n ) was t h e f i r s t l a r g e m a n u f a c t u r e r i n Canada t o move d i r e c t l y i n t o t h e h o u s i n g i n d u s t r y and r e m a i n i n . i t i . . - ! , A l c a n now o p e r a t e s a f a c t o r y i n Woodstock, O n t a r i o , p r o d u c i n g c o m p l e t e houses i n two s e c t i o n s , t h r o u g h i t s w h o l l y owned s u b s i d i a r y A l c a n . D e s i g n Homes L i m i t e d . The S t e e l Company of Canada ( S t e l c o ) has now formed a m a r k e t i n g group t o work e x c l u s i v e l y i n t h e h o u s i n g f i e l d . I t w i l l work c l o s e l y w i t h customers i n d e v e l o p i n g new h o u s i n g d e s i g n s , a s s i s t i n f i e l d ' d e v e l o p m e n t work, and c o - o p e r a t e i n s o l v i n g f a b r i c a t i o n and e r e c t i o n problems (Dack, 1967). Polymer C o r p o r a t i o n has t a k e n i t s f i r s t s t e p out of p e t r o c h e m i -c a l s i n t o i n d u s t r i a l i z e d b u i l d i n g , h a v i n g r e c e n t l y p u r c h a s e d t h e e x c l u s i v e C a n a d i a n l i c e n s e t o u se t h e Uniment s y s t e m o f S t r e s s e d S t r u c t u r e s I n c o r -p o r a t e d ( D e n v e r ) ( F i n a n c i a l P o s t , 1 9 7 0 c ) . The f o r e s t p r o d u c t s i n d u s t r i e s i n Canada have n o t y e t made at t e m p t s t o f o l l o w t h e l e a d of t h e i r c o u n t e r p a r t s . i n t h e U.S.A. or t h e above'Canadian c o r p o r a t i o n s . I f more competing m a n u f a c t u r e r s become i n -v o l v e d d i r e c t l y i n . h o u s i n g , i t would be r e a s o n a b l e t o assume t h a t m a j o r f o r e s t p r o d u c t s companies would f o l l o w s u i t . Not t o do so would s u r e l y l e a d t o a f u r t h e r d e t e r i o r a t i o n i n t h e i r h o u s i n g m a r k e t s s h o u l d competing companies e n t e r r e s i d e n t i a l c o n s t r u c t i o n w i t h non-wood frame b u i l d i n g methods f o r s i n g l e - f a m i l y d w e l l i n g s and l o w — r i s e m u l t i p l e d w e l l i n g s . Due t o t h e l a c k o f p a r t i c i p a t i o n o f major c o r p o r a t i o n s i n r e s i -d e n t i a l c o n s t r u c t i o n i n Canada, v e r t i c a l i n t e g r a t i o n o f m a t e r i a l s s u p p l i e r s and b u i l d e r s has v i r t u a l l y no e f f e c t on m a t e r i a l s use i n b u i l d i n g a t t h e p r e s e n t t i m e . A l t h o u g h i t may be argued t h a t c h a n g i n g l a b o u r c o s t s i n t h e c o n -s t r u c t i o n i n d u s t r y i n f l u e n c e t h e c o m p e t i t i v e a b i l i t y o f wood, i t i s f e l t , t h a t t h e main e f f e c t o f i n c r e a s i n g l a b o u r c o s t s i s t h e s u b s t i t u t i o n o f c a p i t a l f o r l a b o u r i n t h e c o n s t r u c t i o n p r o c e s s . How t h i s a c t u a l l y a f f e c t s t h e p o s i t i o n o f wood as a b u i l d i n g m a t e r i a l w i l l be d e a l t w i t h i n t h e d i s -c u s s i o n o f i n d u s t r i a l i z e d b u i l d i n g . PENETRATION OF SUBSTITUTES. FOR WOOD INTO THE HOUSING MARKET An attempt w i l l be made t o draw t o g e t h e r t h e s c a t t e r e d , incom-p l e t e , and sometimes c o n f l i c t i n g i n f o r m a t i o n . p e r t a i n i n g t o t h e n a t u r e and e x t e n t o f p e n e t r a t i o n o f wood s u b s t i t u t e s i n t o t h e h o u s i n g m a r ket. Recent and i m p o r t a n t p o t e n t i a l developments w i l l be d i s c u s s e d f o r t h e main m a t e r -i a l s groups i n v o l v e d . Aluminum Some o f t h e advantages o f aluminum f o r c o n s t r u c t i o n u ses c i t e d by Bower (1966) a r e i t s l i g h t n e s s , h i g h s t r e n g t h - t o - w e i g h t r a t i o , good r e s i s t a n c e t o c o r r o s i o n and good r e f l e c t i n g p r o p e r t i e s . However, b e -cause o f i t s r e l a t i v e l y h i g h c o s t , aluminum has l a r g e l y been c o n f i n e d t o a r c h i t e c t u r a l and s e m i - s t r u c t u r a l a p p l i c a t i o n s . Aluminum has been s u c c e s s f u l i n p e n e t r a t i n g t h e h o u s i n g market i n a few a p p l i c a t i o n s i n w h i c h wood has been used t r a d i t i o n a l l y . I t i s used p r i m a r i l y i n windows, s i d i n g , f a s c i a , and s o f f i t s ( P h i l l i p s , 1 9 6 7 ) . A l c a n D e s i g n Homes i s r e p o r t e d l y u s i n g aluminum f o r door hardware, l o u v r e s , v e n t s , f o i l v a p o u r , b a r r i e r , e x t e r i o r door t h r e s h o l d s and t h e e l e c t r i c w i r i n g s ystem i n i t s f a c t o r y - b u i l t homes ( H o l r o y d , 1 9 6 9 ) , most of w h i c h do n o t r e p l a c e wood. A c c o r d i n g t o P h i l l i p s ( 1 9 6 7 ) , 50 p e r c e n t of windows e n t e r i n g new houses i n t h e U n i t e d S t a t e s a r e aluminum. A s t u d y by Benson.(1968b) appears t o s u p p o r t t h i s f i g u r e . H i s s t u d y i n d i c a t e d t h a t 45 p e r c e n t Of t h e new houses b u i l t i n t h e U.S. u s e aluminum windows p r i m a r i l y , and an a d d i t i o n a l 15 p e r c e n t use b o t h wood and aluminum. The s t u d y r e v e a l e d t h a t a c h i e f f a c t o r f a v o u r i n g aluminum windows i s the m a i n t e n a n c e - f r e e c h a r a c t e r i s t i c as opposed t o wood windows w h i c h r e q u i r e f r e q u e n t p a i n t -i n g . F u r t h e r m o r e , aluminum u n i t s a r e l e s s e x p e n s i v e w i t h r e s p e c t t o b o t h p u r c h a s e p r i c e and i n s t a l l e d c o s t s , and a r e thus used more e x t e n s i v e l y i n l o w e r p r i c e d homes. The main advantages o f wood windows c i t e d were b e t t e r i n s u l a t i o n and appearance. As aluminum window m a n u f a c t u r e r s i m -p r o v e t h e appearance of t h e i r p r o d u c t s t h r o u g h t h e use of baked-on f i n -i s h e s , t h e p r i c e d i f f e r e n t i a l may r e s u l t i n f u r t h e r s u b s t i t u t i o n o f wood i n f a v o u r o f aluminum. As s i d i n g , aluminum h o l d s a s m a l l e r s h a r e of t h e m a r k e t , e s t i -mated by Benson (1968a) t o be about n i n e p e r cent of t h e U.S. s i d i n g m a r k e t. T h i s was c o r r o b o r a t e d by a s u r v e y of b u i l d e r s by t h e A m e r i c a n Plywood A s s o c i a t i o n (Crow's F o r e s t P r o d u c t s D i g e s t , 1970). F o r t h e same y e a r , P h e l p s (1970) i n d i c a t e d t h a t non-wood m a t e r i a l s were employed on 70 p e r c e n t of t h e F H A - i n s p e c t e d s i n g l e - f a m i l y houses i n h i s s u r v e y . I t may be n o t e d t h a t about 80 p e r c e n t of aluminum s i d i n g i n t h e U.S. goes i n t o r e m o d e l l i n g and t h e r e m a i n d e r i n t o new c o n s t r u c t i o n ( B u i l d i n g M a t e r -i a l s M e r c h a n d i s e r , 1967b) . These aluminum p r o d u c t s a r e a v a i l a b l e i n a Y ^ r i s t y o f c o l o u r s , t e x t u r e s , and s t y l e s . One of t h e m a j o r advantages of aluminum s i d i n g (as w e l l as most o t h e r non-wood s i d i n g s ) i s t h a t i t i s g e n e r a l l y c o n s i d e r e d m a i n t e n a n c e - f r e e . The i n t r o d u c t i o n of p o l y v i n y l f l u o r -i d e f i n i s h e s on aluminum s i d i n g v i r t u a l l y e l i m i n a t e d p a i n t i n g , and some man-u f a c t u r e r s a r e o f f e r i n g 30-year g u a r a n t e e s on t h e s e p r o d u c t s . However, such m a i n t e n a n c e - f r e e f i n i s h e s can be used on a v a r i e t y o f s u b s t r a t e s , i n c l u d i n g wood. ( I t may be n o t e d t h a t U.S. Plywood-Champion P a p e r s be-gan p r o d u c t i o n o f wood s i d i n g c o a t e d w i t h T e d l a r ( a p o l y v i n y l f l u o r i d e f i n i s h d e v e l o p e d by Dupont) i n 1963). Benson a l s o found t h a t the c o s t o f aluminum s i d i n g was e q u a l t o t h a t f o r f i b r e b o a r d and plywood, and s l i g h t l y l o w e r t h a n f o r lumber. However, a r c h i t e c t u r a l s t y l e and the home-buyer's p r e f e r e n c e s a r e a l s o i m p o r t a n t i n d e t e r m i n i n g t h e s i d i n g employed. I n f a c t , Zaremba (1963) found t h a t consumer p r e f e r e n c e had a v e r y s t r o n g i n - -f l u e n c e on t h e s i d i n g m a t e r i a l used. O f t e n a number of m a t e r i a l s ' c a n be" used s a t i s f a c t o r i l y f o r a g i v e n house s t y l e ; hence s t y l e s , a l t h o u g h t h e y may i n f l u e n c e t h e c h o i c e o f m a t e r i a l s , do n o t n e c e s s a r i l y d e t e r m i n e the s i d i n g m a t e r i a l s used. W i t h r e s p e c t t o p r e f e r e n c e s , lumber appears t o be f a v o u r e d f o r s i d i n g , a t l e a s t i n h i g h - p r i c e d houses. The t o t a l usage o f aluminum p e r new house i n the U.S. was r e p o r t e d as 300 pounds by P h i l l i p s ( 1 9 6 7 ) . I n c o m p a r i s o n , A l c a n D e s i g n Homes i s r e p o r t e d t o be u s i n g a p p r o x i m a t e l y 1200 pounds of aluminum p e r house ( t o t a l house w e i g h t i s 18 t o n s ) c o n s t r u c t e d a t i t s Woodstock, O n t a r i o p l a n t . No average s t a t i s t i c s comparable t o t h o s e c i t e d above f o r t h e U.S.A. a r e a v a i l a b l e f o r Canada. A p r o m i s i n g development i s t h a t o f s t r u c t u r a l s a n d w i c h p a n e l s i n w h i c h aluminum i s used as a f a c i n g m a t e r i a l bonded' t o a t h i c k l i g h t w e i g h t c o r e (Bower, 1966). I n s u c h p a n e l s , the aluminum p r o v i d e s t h e s t r e n g t h w h i l e the c o r e s e p a r a t e s t h e f a c e s t o p r o v i d e r i g i d i t y , and a l s o a c t s as b u l k i n s u l a t i o n . As p r e v i o u s l y i n d i c a t e d , t h e c o s t o f s u c h systems u s i n g foamed p l a s t i c c o r e s has p r e v e n t e d w i d e s p r e a d c o m m e r c i a l p r o d u c t i o n up t o t h e p r e s e n t t i m e . More r e c e n t l y , A l c o a has d e v e l o p e d two t y p e s of aluminum systems f o r house c o n s t r u c t i o n known as t h e ' A l u m i f r a m e System" and t h e " R i b W a l l B u i l d i n g . S y s t e m " ( T i b b o t , 1 9 7 0 ) , B o t h . o f t h e s e b u i l d i n g systems a r e i n an a d v a n c e d , s t a t e o f . d e v e l o p m e n t , b u t n e i t h e r i s c o m m e r c i a l l y , a v a i l a b l e y e t . The "Alumiframe System" i s composed of a number o f e x t r u d e d aluminum components, i n c l u d i n g window and door f r a m e s , 2 x 3 s t u d s and p l a t e s f o r use i n i n t e r i o r p a r t i t i o n s , and other, s t r u c t u r a l components i n c l u d i n g f l o o r beams and r o o f t r u s s e s . S tuds and p l a t e s a r e p e r f o r a t e d t o a l l o w f o r w i r i n g a nd.plumbing, and no s p e c i a l t o o l s o r i h o l e d r i l l i n g a r e r e q u i r e d . A development house u s i n g t h i s system was b u i l t j o i n t l y b y Ryan Homes and A l c o a . Aluminum 2 x 6 f l o o r j o i s t s - ^ w e r e u s e d o v e r t h e c o n v e n t i o n a l basement, and plywood d e c k i n g was screwed o n t o t h e j o i s t s . The p r e - a s s e m b l e d w a l l p a n e l s u s e d 2 x 4 aluminum s t u d s e and t h e r o o f t r u s s e s were f a b r i c a t e d o f aluminum. Some lumber was i n c o r p o r a t e d i n t o i t h e f r a m e , b u t most o f i t was of aluminum. A l t h o u g h t h e c o s t a n a l y s i s of t h i s s y s t e m - i s n o t - y e t c o m p l e t e , i t i s f e l t t h a t i t w i l l be c o m p e t i t i v e w i t h i n a few y e a r s , and t h a t t h e w a l l s y s t e m may,be c o m p e t i t i v e t o d a y . The " R i b W a l l B u i l d i n g System" has been u s e d t o b u i l d b o t h a r a n c h s t y l e house and a t w o . s t o r e y , four, f a m i l y townhouse. I n t h e r a n c h s t y l e h o u s e , t h r e e main components were u s e d : t h e r i b w a l l p a n e l , window p a n e l , and door p a n e l , a l l o f w h i c h had a baked enamel f a c t o r y f i n i s h . T h i s s y s t e m used s t e e l f l o o r j o i s t s t o w h i c h t h e plywood deck was f a s t e n e d . I n d i v i d u a l - p a n e l s .(of a l l t h r e e t y p e s ) . w e r e . f i r s t j o i n e d t o g e t h e r on t h e s i t e and then, t h e w h o l e w a l l , e r e c t e d . An I n e x p e r i e n c e d f i v e man crew was a b l e t o e r e c t . t h e w a l l s i n 9--1/2 h o u r s . R i g i d p o l y s t y r e n e i n s u l a t i o n was g l u e d d i r e c t l y t o t h e i n s i d e o f t h e w a l l panels.... I n . t h i s p a r t i c u l a r h o use, wood r o o f t r u s s e s were u s e d , and t h e remainder..of t h e i n t e r i o r f i n i s h i n g was. done.by c o n v e n t i o n a l t e c h n i q u e s . The townhouse used t e c h n i q u e s s i m i l a r t o t h o s e i n t h e r a n c h h ouse, w i t h some v a r i a t i o n s , i n c l u d i n g t h e use o f a c r a n e . t o p l a c e t h e much l a r g e r w a l l p a n e l s i n t o p o s i t i o n . Rather, t h a n t h r e e b a s i c , components t h e r e were o n l y two: a r i b w a l l p a n e l , and a window-door p a n e l , t h e p a n e l s b e i n g 16.stfeet h i g h r a t h e r t h a n .8 f e e t as i r i t h e . c a s e of t h e r a n c h house. The c l a i m has been made t h a t t h i s s y t e m . w i l l be more com-p e t i t i v e t h a n c o n v e n t i o n a l wood frame b u i l d i n g methods. S t e e l The i n t e r e s t w h i c h s t e e l m a n u f a c t u r e r s have i n . t h e h o u s i n g market has a l r e a d y been i n d i c a t e d . T h i s i n t e r e s t e x t e n d s i n t o b o t h m u l t i - f a m i l y and s i n g l e - f a m i l y d w e l l i n g s . A c c o r d i n g t o Dack ( 1 9 6 7 ) , t h e t y p i c a l , house r e c e n t l y . u s e d about one t o n of s t e e l , a f i g u r e w h i c h s t e e l , a u t h o r i t i e s f e l t c o u l d be r a i s e d t o t h r e e t o n s t h r o u g h . t h e development o f s u i t a b l e p r o d u c t s and b u i l d i n g t e c h n i q u e s . S i n c e t h e n , s t e e l makers have begun m a r k e t i n g s e v e r a l p r o d u c t s f o r use i n s i n g l e - f a m i l y d w e l l i n g s . I n 1967, t h e "Mod" h ouse, b u i l t o f s t e e l , b r i c k , a n d c o n c r e t e , was shown a t t h e N a t i o n a l Home Show i n T o r o n t o ( F i n a n c i a l P o s t , 1967). I t u s e d s t e e l wherever, p r a c t i c a b l e ^ a n d , . . a l t h o u g h n o t a. c o m m e r c i a l p r o d u c t , s t i m u l a t e d c o n s i d e r a b l e i n t e r e s t , and i s s y m b o l i c o f e f f o r t s b e i n g made by s t e e l p r o d u c e r s t o e n t e r t h e h o u s i n g f i e l d . L i g h t gauge s t e e l , t h e most l o g i c a l , and .promising, c o n t e n d e r f o r t h e h o u s i n g m a r k e t , has been used i n .commercial a n d . i n d u s t r i a l b u i l d i n g s i n s u c h a p p l i c a t i o n s as r o o f i n g , decking,, f l o o r i n g , c l a d d i n g , c e i l i n g f i x -t u r e s , door frames and o t h e r forms of t r i m ( H i l l , H.V., 1 9 6 6 ) . The n a t u r e o f s t e e l , as p r e v i o u s l y o u t l i n e d , r e q u i r e s t h a t i t be u s e d i n c o m b i n a t i o n w i t h . o t h e r m a t e r i a l s . One o f the c h i e f o b j e c t i o n s t o l i g h t gauge s t e e l has been t h e p o s s i b i l i t y o f . c o r r o s i o n , b u t w i t h t h e r e c e n t developments i n baked enamel and. p l a s t i c c o a t i n g s , t h i s , p r o b l e m has been v i r t u a l l y e l i m i n a t e d . A c c o r d i n g , t o H i l l , H. V. (1966)., t h e r e a r e two l i g h t - w e i g h t s t e e l frame h o u s i n g systems . i n use i n England, w h i c h . a r e r e p o r t e d l y b e i n g s o l d a t . c o m p e t i t i v e p r i c e s , whether t h e s e would meet C a n a d i a n b u i l d i n g codes or be c o m p e t i t i v e i n Canada a r e unanswered q u e s t i o n s . I n Canada, Anthes P r o d u c t s L i m i t e d has been d e v e l o p i n g a s t e e l j o i s t w h i c h .obtained p r o v i s i o n a l a c c e p t a n c e by CMHC i n 1967 ( F i n a n c i a l , P o s t , 1 9 6 7 ) . T h i s p r o d u c t ( o f l i g h t gauge . c o l d r o l l e d s t e e l ) was g i v e n i t s f i r s t f i e l d t r i a l i n a v e n t u r e by C o n s o l i d a t e d B u i l d i n g C o r p o r a t i o n i n 1967, i n c o - o p e r a t i o n w i t h A nthes ( C a n a d i a n B u i l d e r . , 1967). Advantages c i t e d f o r t h i s t y p e o f j o i s t a r e easy i n s t a l l a t i o n by u n s k i l l e d l a b o u r , no w a r p i n g , and c l e a r span basements. A l t h o u g h t h e r e were s t i l l m i n o r p r o b -lems t o be worked o u t , i t was f e l t t h a t t h e r e was a market f o r su c h j o i s t s i f t h e y c o u l d be p r o v i d e d i n s u f f i c i e n t . l e n g t h s t o p r e v e n t s i t e work, and become as e a s i l y a v a i l a b l e as 1 lumber. More r e c e n t l y , t h e N a t i o n a l House B u i l d e r s Association...employed b o t h s t e e l j o i s t s and s t e e l s t u d s i n i t s e x p e r i m e n t a l house b u i l t i n K i t c h e n e r . , O n t a r i o (McCance, 1969b). These f l o o r j o i s t s were employed If on both, t h e f i r s t and second, f l o o r s , w h i l e t h e 1-5/8 i n . s t e e l s t u d s were us e d f o r a l l n o n - l o a d b e a r i n g i n t e r i o r p a r t i t i o n s . I t was c l a i m e d t h a t s t e e l s t u d s r e q u i r e l e s s l a b o u r t o i n s t a l l and t h a t p r e d r i l l e d h o l e s f c a t f one f o o t i n t e r v a l s t o accommodate w i r i n g speed up t h i s j o b . H o y l e .(1970) has s t a t e d t h a t p r e - d r i l l e d h o l e s i n wood s t u d s have been o f f e r e d t o b u i l d -e r s i n t h e p a s t b u t were n o t s u c c e s s f u l because of r e d u c e d v e r s a t i l i t y and u s e f u l n e s s of s u c h s t u d s a t t h e b u i l d i n g s i t e . T h i s o b j e c t i o n does n o t a p p l y t o p r e - d r i l l i n g o f s t e e l s t u d s s i n c e t h e h o l e s a r e d r i l l e d i n a l l s u c h s t u d s . D u r i n g .1968 and t h e s p r i n g o f 1969, t h e r e c o r d h i g h lumber p r i -ces .brought w i t h i t many c l a i m s t h a t . t h e p r i c e o f s t e e l s t u d s was.compet-i t i v e , w i t h wood s t u d s f o r n o n - l o a d b e a r i n g i n t e r i o r p a r t i t i o n s . I n commer-c i a l b u i l d i n g s , s t e e l s t u d s f o r i n t e r i o r p a r t i t i o n s have found a f a i r de-g r e e o f a c c e p t a n c e o v e r t h e p a s t few y e a r s ( C a n a d i a n F o r e s t I n d u s t r i e s , 1969).. A l t h o u g h n o n - l o a d b e a r i n g s t e e l s t u d s were c l a i m e d t o have a compet-i t i v e edge o v e r lumber ( a t l e a s t i n some, a r e a s ) , t h e s u b s t a n t i a l drop i n lumber p r i c e s i n t h e l a t t e r h a l f of . 1969 has r e v e r s e d t h i s s i t u a t i o n i n most c a s e s . I n H o y l e ' s (1970) a n a l y s i s of s t e e l v e r s u s wood'.studs, t h e non-c o m b u s t i b l e n a t u r e of t h e f o r m e r i s p o i n t e d out as a d e f i n i t e advantage . i n m u l t i - f a m i l y , d w e l l i n g s . He i n d i c a t e s . t h a t wood s t u d w a l l s are,, on t h e a v e r a g e , s t i f f e r . t h a n s t e e l s t u d w a l l s , have h i g h e r . b e n d i n g . s t r e n g t h , and a r e .about 2-1/2 t i m e s s t r o n g e r i n . c o m p r e s s i o n . . T h i s l a t t e r p r o p e r t y i s of l i t t l e i m p o r t a n c e I n n o n - l o a d b e a r i n g w a l l s and, g i v e n t h a t t h e b e n d i n g s t r e n g t h o f s t e e l s t u d s i s s u f f i c i e n t f o r t h e i n t e n d e d p u r p o s e , t h e g r e a t e r b e n d i n g s t r e n g t h of wood s t u d s may be v i e w e d as o v e r - d e s i g n r a t h e r t h a n a s r e a l a dvantage. I t would appear t h a t , i n n o n - l o a d b e a r i n g w a l l s , s t e e l s t u d s w i l l c o n t i n u e t o t h r e a t e n t h e p o s i t i o n o f wood s t u d s , p a r t i c u l a r l y i f lumber p r i c e s r i s e . r e l a t i v e . t o s t e e l p r i c e s . However, i n e x t e r i o r l o a d b e a r i n g w a l l s , t h e r e q u i r e d u s e o f h e a v i e r gauge s t e e l f o r s t u d s w o u l d a t l e a s t . d o u b l e t h e i r p r i c e . Thus, H o y l e c o n c l u d e s t h a t t h e r e i s no a p p a r e n t r e a s o n f o r s t e e l t o r e p l a c e wood i n e x t e r i o r w a l l s . M e t a l s h e l v i n g i s a n o t h e r a r e a , i n w h i c h s t e e l p r o d u c t s a r e com-p e t i n g . . A s t u d y by Benson and Host (1968) d e t e r m i n e d t h a t t h e propor-:' t i o n o f m e t a l s h e l v i n g used i n s i n g l e - f a m i l y homes rang e d from one p e r c e n t i n k i t c h e n s t o 21 p e r c e n t i n garage and u t i l i t y a r e a s . The r e m a i n -i n g s h e l v i n g was composed o f . l u m b e r , plywood, and p a r t i c l e b o a r d . M e t a l s h e l v e s were s a i d t o have t h e advan t a g e s o f b e i n g warp f r e e and easy t o i n s t a l l s i n c e t h e y a r e g e n e r a l l y p u r c h a s e d r e a d y t o f a s t e n i n p l a c e . On t h e n e g a t i v e . s i d e , t h e y a r e n o t r e a d i l y a c c e p t e d by home b u y e r s , have a t i n n y a p p e a r a n c e , r a t t l e , and a r e more e x p e n s i v e . T h i s l a s t d i s a d v a n t a g e c i t e d was based on. p u r c h a s e p r i c e r a t h e r t h a n i n - p l a c e c o s t s s i n c e the., b u i l d e r s s u r v e y e d were unaware of t h e i n - p l a c e c o s t s o f t h e i r s h e l v i n g . The f i n d i n g s o f t h i s s t u d y s u g g e s t t h a t s t e e l w i l l meet o n l y , l i m i t e d s u c c e s s i n .the a r e a o f s h e l v i n g . M e t a l d o o r s a r e a more r e c e n t e n t r y i n i t h e h o u s i n g m a r k e t . U.S. S t e e l has d e v e l o p e d a s t e e l door i n p a r t n e r s h i p w i t h a m i l l w o r k company ( R i c h , 1 9 6 5 ) . T h i s door comes from t h e f a c t o r y p re-hung, d o e s , n o t . w a r p , c h i p , s c r a t c h , o r p e e l and has.good i n s u l a t i o n p r o p e r t i e s . M e t a l .clad d o o r s a r e a l s o b e i n g produced, i n O n t a r i o f o r . h o u s e s . . These doors have m e t a l c l a d d i n g on b o t h s i d e s , wood s t r i p p i n g around t h e edges, and a p o l y u r e t h a n e foam core.. Such doors are.much h i g h e r p r i c e d t h a n wood doors- and a r e t h u s u s e d p r i m a r i l y i n houses i n .the h i g h p r i c e r a n g e . S t e e l s i d i n g i s a n o t h e r r e c e n t development. The same c o a t i n g t e c h n i q u e s w h i c h a r e used f o r aluminum, can a l s o be a p p l i e d t o s t e e l . As e a r l y as 1967, s t e e l s i d i n g was r e p o r t e d l y u s e d on hundreds o f new houses i n S o u t h e r n O n t a r i o ( F i n a n c i a l P o s t , 1967) . S t e e l s i d i n g w i t h p r o t e c t i v e c o a t i n g s d o e s . n o t c r a c k , f l a k e , c h i p , b l i s t e r , o r p e e l , and i s economi-c a l l y c l e a n e d and m a i n t a i n e d . . As w i t h aluminum, s t e e l s i d i n g i s a v a i l -a b l e i n a v a r i e t y o f - t e x t u r e s and c o l o u r s . S t e l c o began m a r k e t i n g p r e -p a i n t e d s t e e l house s i d i n g . i n 1970 CGlobe and M a i l , 1970a).. A s i d e I n t e r -n a t i o n a l C o r p o r a t i o n , a w h o l l y owned s u b s i d i a r y o f U.S. S t e e l , i s a l s o e n t e r i n g t h e C a n a d i a n market w i t h s t e e l s i d i n g t h a t s i m u l a t e s a w o o d . g r a i n , p a t t e r n and i s f i n i s h e d w i t h v i n y l . A 30-year f a c t o r y g u a r a n t e e on. t h e s e p r o d u c t s p l a c e s them among t h e m a i n t e n a n c e - f r e e s i d i n g s . S t e e l o f f i c i a l s c l a i m t h a t s t e e l s i d i n g i s s l i g h t l y . l o w e r p r i c e d t h a n aluminum s i d i n g ( F i n a n c i a l P o s t , 1 967), b u t b o t h a r e h i g h e r , p r i c e d t h a n wood, s i d i n g . W i t h i n s t a l l a t i o n and m a i n t e n a n c e i n c l u d e d i n the t o t a l c o s t , aluminum and s t e e l a r e c l a i m e d t o be c o m p e t i t i v e with.wood s i d i n g s . P l a s t i c s The p l a s t i c s i n d u s t r y has f o r many y e a r s c l a i m e d t o be on t h e v e r g e o f . e n t e r i n g t h e c o n s t r u c t i o n market on a l a r g e s c a l e . F o r a number of r e a s o n s , no s u c h b r e a k t h r o u g h has.been, a c h i e v e d . A g r a d u a l i n c r e a s e i n t h e u s e o f . . p l a s t i c s i n , c o n s t r u c t i o n , has o c c u r r e d , and t h i s i n d u s t r y now has a number, o f p r o m i s i n g d e v e l o p m e n t s . The h i g h , p r i c e of. p l a s t i c s has been a major impediment t o more w i d e s p r e a d u s e . Three o t h e r r e a s o n s c i t e d f o r the. s l o w a d o p t i o n o f p l a s t i c s i n . c o n s t r u c t i o n a r e : t h e f i r e h a z a r d and smoke g e n e r a t i o n of p l a s t i c s , a n t i q u a t e d s p e c i f i c a t i o n - t y p e . b u i l d i n g codes, w h i c h d i s c r i m i n a t e a g a i n s t new p r o d u c t s , . a n d l a c k of i n f o r m a t i o n on p l a s t i c s a v a i l a b l e t o . a r c h i t e c t s ( C a n a d i a n P l a s t i c s . , 1969). I n most of ..the a p p l i c a t i o n s , . i n w h i c h p l a s t i c s have met s u c c e s s , t h e r e has been.no r e p l a c e m e n t of wood p r o d u c t s . I n a few i n s t a n c e s , t h e use o f p l a s t i c s has been a t t h e expense of wood pro d u c t s , . a l t h o u g h t h e e x t e n t o f s u b s t i t u t i o n i s d i f f i c u l t t o d e t e r m i n e and. p r o b a b l y q u i t e , s m a l l . A c c o r d i n g to. Salmond ( 1 9 6 9 ) , t h e c o n s t r u c t i o n i n d u s t r y has used 20 t o 24. p e r c e n t of the~U>.\S. p l a s t i c s p r o d u c t i o n i n each of t h e p r e v i o u s 10 y e a r s . I n 1967, Modern P l a s t i c s (1968) r e p o r t e d t h a t t h e t o t a l U.S. p l a s t i c s c o n s u m p t i o n i n b u i l d i n g c o n s t r u c t i o n was c l o s e t o 4 b i l l i o n pounds. Ther e a r e no d a t a f o r t h e r e s i d e n t i a l c o n s t r u c t i o n m a r k e t , •Salmond (1969) i n d i c a t e d t h a t t h e p e r c a p i t a consumption o f p l a s t i c s i n c o n s t r u c t i o n i n t h e U.S.A. and Canada i n 1965 was 12,6 and. 5.8 pounds, r e s p e c t i v e l y . There i s r e a s o n t o b e l i e v e t h a t t h e l a t t e r f i g u r e , i s some-what h i g h s i n c e . h e a l s o r e p o r t e d t h a t p l a s t i c s , c o nsumption i n Canada f i r s t exceeded one b i l l i o n pounds i n 1968. I f t h e same p r o p o r t i o n s h o l d i n . Canada .as i n t h e U.S., the. volume of p l a s t i c s u sed i n b u i l d i n g c o n s t r u c -t i o n i n Canada would have been a p p r o x i m a t e l y 200,000 t o 240,000 pounds i n 1968. P l a t t s (1964a) found i n h i s . s t u d y t h a t p l a s t i c s now dominate t h e f i e l d s : 6 f c o a t i n g s , , c l a d d i n g s , a n d . c o v e r i n g s i n b u i l d i n g . M o d e r n . P l a s t i c s (1968) i n d i c a t e d t h a t p a i n t s , c o a t i n g s , and a d h e s i v e s r e p r e s e n t o v e r h a l f o f t h e p l a s t i c s employed i n t h e b u i l d i n g m a r k e t . These, as w e l l as most o t h e r uses of p l a s t i c s i n h o u s i n g , do h o t compete w i t h wood p r o d u c t s . F o r example,, p o l y e t h y l e n e vapour b a r r i e r s , . . r e i n f o r c e d p l a s t i c s and a c r y l i c s i n g l a z i n g and s k y l i g h t s , p o l y s t y r e n e and a c r y l i c s i n l i g h t i n g and f i x -t u r e s , .and p o l y v i n y l . c h l o r i d e (PVC) e x t r u s i o n s .of g u t t e r s and downspouts . a r e complementary r a t h e r t h a n s u b s t i t u t e p r o d u c t s . A l s o , t h e v e r y . p r o m i s -i n g developments o f d r a i n - w a s t e - v e n t systems of ABS and PVC, and g l a s s r e i n f o r c e d p o l y e s t e r p l u m b i n g and b a t h f i x t u r e s w i l l have l i t t l e o r no e f f e c t on t h e consumption of wood p r o d u c t s . I t i s a l s o , i n t e r e s t i n g t o n o t e t h a t one of t h e l a r g e s t s i n g l e " c o n s t r u c t i o n " u s e s o f p l a s t i c s i s c o n s i d e r e d t o be u r e a , melamine, a n d . p h e n o l i c r e s i n s u s e d i n .the b o n d i n g of wood p a n e l . p r o d u c t s (Modern P l a s t i c s , 1 9 6 8 ) . I n t h e a r e a o f f l o o r i n g , v i n y l and v i n y l - a s b e s t o s t i l e s dominate s u c h a r e a s as k i t c h e n s and bathrooms, and have found.wide useii.In. r e c r e a -t i o n and .play rooms. Foam-backed t y p e s o f seamless v i n y l f l o o r i n g have more r e c e n t l y been i n t r o d u c e d (Modern P l a s t i c s , 1 9 6 8 ) . These f l o o r s u r -f a c e s a r e b e i n g promoted f o r , a l l a r e a s o f , t h e house, n o t m e r e l y u t i l i t y a r e a s , and.thus r e p r e s e n t p o t e n t i a l c o m p e t i t i o n , f o r f i n i s h e d w o o d . f l o o r -i n g . S y n t h e t i c . c a r p e t i n g o f a c r y l i c , n y l o n , and. p o l y p r o p y l e n e i s a n o t h e r c o n t e n d e r i n t h e f i n i s h e d f l o o r i n g m a r k e t , a l o n g w i t h . t r a d i t i o n a l c a r p e t i n g m a t e r i a l s . The use o f w a l l - t o - w a l l c a r p e t s ( s y n t h e t i c o r o t h e r -w i s e ) i n s t a l l e d b y . t h e b u i l d e r has a l r e a d y l e d t o a s i g n i f i c a n t l o s s o f wood f l o o r i n g m a r k e t s , p a r t i c u l a r l y i n ap a r t m e n t s where c a r p e t s . c a n be used v e r y e f f e c t i v e l y , t o r e d u c e i m p a c t . n o i s e t r a n s m i s s i o n . J o s e p h s o n (1969) I n d i c a t e d t h a t , s i n c e 1955, t h e s h a r e o f t h e r e s i d e n t i a l f l o o r i n g h e l d by wood p r o d u c t s has dropped from. t w o ^ t h l r d s ? i f t o o n e - q u a r t e r o f t h e t o t a l m a r k e t , w h i l e c a r p e t i n g and o t h e r non-wood .mater-i a l s , now c o v e r t h e o t h e r .75 p e r c e n t o f t h e t o t a l f l o o r a r e a of. new d w e l l -i n g . u n i t s b u i l t . I n Canada, t h e s u b s t i t u t i o n of. n o n - w o o d \ f l o o r i n g . m a t e r -i a l s has b e e n . l e s s d r a s t i c , p r o b a b l y b e c a u s e o f .the much l o w e r use o f c o n c r e t e s l a b f o u n d a t i o n s i n s i n g l e - f a m i l y , houses... C a r p e t i n g made of s y n t h e t i c f i b r e s , p a r t i c u l a r l y n y l o n . a n d . a c r y l o n , have had much s u c c e s s to d a t e , and t h e p o t e n t i a l r e m a i n s . h i g h f o r w a l l - t o - w a l l c a r p e t i n g i n g e n e r a l . The v e r y good i n s u l a t i n g v a l u e o f some.of t h e foamed p l a s t i c s has a l r e a d y been i n d i c a t e d . A l t h o u g h p o l y u r e t h a n e foam has t h e . b e s t i n -s u l a t i n g p r o p e r t i e s , p o l y s t y r e n e . i s . the. l o w e s t i n c o s t of t h o s e a v a i l -a b l e ( P l a t t s , 1 9 6 4 a ) , w h i c h a c c o u n t s f o r i t s g r e a t e r u s e up ..to t h e p r e -s e n t t i m e . As e a r l y as 1967, s e v e r a l h i g h - r i s e apartment b u i l d i n g s were r e p o r t e d t o be c o m p l e t e l y i n s u l a t e d w i t h u r e t h a n e foam (Modern. P l a s t i c s , . 1 968); and i t . i s now one o f t h e m a j o r . m a r k e t s f o r p l a s t i c s . i n c o n s t r u c -t i o n . . These foams have been r e l a t i v e l y w e l l a c c e p t e d as i n s u l a t i o n and appear d e s t i n e d t o c a p t u r e much o f t h i s market from t h e t r a d i t i o n a l m i n -e r a l wool*and i n s u l a t i o n b o a r d . A n o t h e r s i g n i f i c a n t development u s i n g . f o a m e d p l a s t i c s i s t h e l o a d b e a r i n g s a n d w i c h p a n e l w i t h a foamed p l a s t i c c o r e . S i n c e a c o r e m a t e r i a l must be a b l e t o s u p p o r t the. l o a d b e a r i n g s k i n s , styrene..foams ( w h i c h b e g i n t o s o f t e n a t 200°F. and a r e . s u b j e c t t o cr e e p under s u s t a i n e d l o a d ) appear somewhat l i m i t e d i n t h e i r , p o t e n t i a l as s u c h . a . c o r e m a t e r i a l . ( P l a t t s , 1 964a). The b e t t e r h e a t r e s i s t i n g . p r o p e r t i e s of u r e t h a n e foams - i n d i c a t e s a g r e a t e r l o n g - r a n g e p o t e n t i a l as a c o r e f o r . s a n d w i c h p a n e l s t h a n any o t h e r p l a s t i c foam.. Mt P l a t t s (1964a) indicated that.the technology f o r producing metal faced panels with a urethane foam core at h i g h production rates already e x i s t s , but that the cost of such components would not be. competitive with wood frame systems f o r many years. Foams can be used i n .conjunction with a v a r i e t y of skin materials, including aluminum, s t e e l , plywood, asbestos cement, and glass r e i n f o r c e d . p l a s t i c s (Makowski, 1966). A. de s c r i p t i o n of several d i f f e r e n t panels of this, general. type\ r sboth commercial and i n some stage of development, has been given by Makowski. He also indicated that phenolic r e s i n foam core (used:with glass r e i n f o r c e d p l a s t i c s ) and expanded.PVC,are f i n d i n g use as core material i n sandwich panels. Many one and two-storey buildings are reported to have been b u i l t i n which large f a c t o r y - b u i l t p l a s t i c sandwich panels were used as external load : bearing walls. One .set of townhouses employing glass f i b r e reinforced r e s i n panels was even described as low cost (Makowski, 1966). In c i t i n g the f e a s i b i l i t y of. f u l l y load.bearing walls with ex-, panded foam cores and stressed GRP skins, the F i n a n c i a l Post (1968a) has indicated that external walls offer.the biggest p o t e n t i a l for p l a s t i c s . Modern P l a s t i c s (1968) indicated that r e i n f o r c e d polyester panels and sandwiches are enjoying reasonable sa l e s . I t i s reported that the use of GRP panels with a backing of r i g i d urethane foam i s growing r a p i d l y , but housing was not c i t e d as a market. I t would appear that economics i s s t i l l holding back large-scale commercial production of sandwich panels with p l a s t i c foam cores. How-ever, the p o t e n t i a l of such panels i s tremendous if . the p r i c e structure can be made competitive with wood frame construction. ..A.recent e n t r y i n t o t h e h o u s i n g m a r k e t has been v i n y l , s i d i n g . A l t h o u g h i n t r o d u c e d i n t h e U.S.A. i n .1963, i t has more r e c e n t l y e n t e r e d t h e C a n a d i a n market. H i g h t h e r m a l . e x p a n s i o n , and c o n t r a c t i o n has i n t h e p a s t r e s u l t e d i n bowing o f the p a n e l s , b u t new i n s t a l l a t i o n t e c h n i q u e s ' have overcome t h i s p r o b l e m (Modern E l a s t i c s , 1968). I t i s c o n s i d e r e d a m a i n t e n a n c e - f r e e m a t e r i a l and i s b e i n g s o l d w i t h a 30-year g u a r a n t e e . W Benson's (1968a) s t u d y on s i d i n g m a t e r i a l s i n the U.S. d o e s . n o t m e n t i o n v i n y l , and Modern P l a s t i c s (1968) i n d i c a t e d t h a t . n o r e l i a b l e e s t i m a t e s a r e a v a i l a b l e on.the amount of PVC g o i n g i n t o house s i d i n g . A c c o r d i n g t o McCance ( 1 9 6 9 b ) , v i n y l s i d i n g c o s t s about f i v e p e r c e n t more t h a n aluminum. He a l s o n o t e d t h a t t h e Mark V I e x p e r i m e n t a l house of t h e N a t i o n a l . House B u i l d e r s A s s o c i a t i o n u s e d v i n y l s i d i n g , f a s c i a , s o f f i t s , and e a v e s , r e f l e c t i n g t h e i n t e r e s t o f - t h e house b u i l d i n g i n d u s t r y i n t h i s new m a t e r i a l . H i g h - p r e s s u r e d e c o r a t i v e l a m i n a t e s u s i n g p h e n o l i c and melamine r e s i n s are.commonly u s e d . i n k i t c h e n . c o u n t e r and. v a n i t y t o p s . .The h a r d a b r a s i o n and c h e m i c a l r e s i s t a n t s u r f a c e s have l e d , t o t h e v i r t u a l e l i m i -n a t i o n of c o m p e t i t i v e p r o d u c t s i n t h e u s e s mentioned.above.. A t t e m p t s t o e x t e n d t h e a p p l i c a t i o n o f h i g h - p r e s s u r e l a m i n a t e s t o v e r t i c a l w a l l , s u r f a c e s have been r e l a t i v e l y u n s u c c e s s f u l . Modern P l a s - . t i c s (1968) s t a t e d t h a t l o w - p r e s s u r e . l a m i n a t e s . o f p o l y e s t e r - i m p r e g n a t e d p a p e r s on v a r i o u s , c o m p o s i t i o n b o a r d s a r e now.'attempting . t o e n t e r t h i s marr k e t , o f f e r i n g p o t e n t i a l c o m p e t i t i o n . t o . d e c o r a t i v e wood veneers.. The most s u c c e s s f u l p l a s t i c p r o d u c t t y p e i n t h i s a r e a t o d a t e has been ,wood-grained v i n y l . f i l m s o ver a v a r i e t y of l o w - c o s t s u b s t r a t e s i n c l u d i n g p l ywood, gypsum b o a r d , and even c o r r u g a t e d c a r d b o a r d ...(Modern P l a s t i c s . , 1968).. T h i s has b e e n . r e f e r r e d t o as one of t h e f a s t e s t g r o w i n g m a r k e t s f o r . p l a s t i c s . Modern g r a i n p r i n t i n g t e c h n i q u e s a r e c a p a b l e of p r o d u c i n g p a t t e r n s on v i n y l . w h i c h a r e h a r d l y d i s t i n g u i s h a b l e , from, n a t u r a l wood, a t t h e same t i m e p r o v i d i n g .a w a t e r r e s i s t a n t , e a s i l y c l e a n e d s u r f a c e . Tane.(1967) c i t e d an i n c r e a s i n g t e n d e n c y towards t h e s u r f a c i n g o f gypsum b o a r d w i t h v i n y l f i l m . He a l s o n o t e d t h a t t h e average p r i c e of a v i n y l c o v e r e d 4 x 8 f t . plywood p a n e l was about $7 compared t o $11 and up f o r . n a t u r a l wood p a n e l s . . W h i l e t h e p r o s p e c t s f o r v i n y l i n d e c o r a t i v e w a l l c o v e r i n g s appear good, t h i s , i s becoming a h i g h l y c o m p e t i t i v e a r e a , with.hardwood plywood p a n e l s . a n d . d i r e c t g r a i n - p r i n t e d h a r d b o a r d s s t i l l s u p p l y i n g t h e v a s t . m a j o r -i t y o f . p a n e l s u s e d . Hardwood plywood i s s t i l l t he f a v o u r e d . m a t e r i a l . The market i s a segmented one w i t h a l a r g e v a r i e t y of s t y l e s and p r i c e s t o s u i t i n d i v i d u a l t a s t e s , i n d i c a t i n g t h a t no s i n g l e m a t e r i a l w i l l be a b l e t o s u p -p l y t h e w h ole m a r k e t . G l a s s f i b r e r e i n f o r c e d p o l y e s t e r (GRP). i s t h e most i m p o r t a n t and b e s t known s t r u c t u r a l p l a s t i c m a t e r i a l . GRP.panels can be m a n u f a c t u r e d w i t h a v a r i e t y of p r o p e r t i e s , d e p e n d i n g . o n . t h e . r e s i n - f i b r e r a t i o and t h e t y p e of f i b r e employed ( B e n j a m i n , 1 9 6 8 ) . U n t i l . t h e p r e s e n t , . GRP p a n e l s have been e x c l u d e d from the h o u s i n g market., l a r g e l y on t h e b a s i s of c o s t . N e v e r t h e l e s s , t h e h i g h s t r e n g t h o f t h e s e m a t e r i a l s has s u s t a i n e d i n t e r e s t i n them.. The. p o t e n t i a l of .sandwich, p a n e l s w i t h , . p l a s t i c .foam c o r e s and GRP f a c e s has a l r e a d y been o u t l i n e d . . GRP. p l u m b i n g . and b a t h f i x t u r e s a r e now b e i n g s o l d , i n some ca s e s as c o m p l e t e f a c t o r y - b u i l t bathroom c o r e u n i t s . . Whether t h e s e w i l l be s u c c e s s f u l o r n o t . s t i l l r e m a i n s t o be s e e n . Only .the. use of c o m p l e t e c o r e u n i t s would r e s u l t i n a r e p l a c e m e n t o f s m a l l volumes of wood. GRP p l a s t i c s have been u s e d i n a v a r i e t y o f non-r e s i d e n t i a l s t r u c t u r e s , o f t e n t a k i n g on e x o t i c .forms. . P o t e n t i a l u ses c i t e d i n h o u s i n g a r e r o o f i n g , c l a d d i n g , , i n t e r n a l components s u c h as p a r - . t i t i o n s , d o o r s , s t a i r c a s e s , a n d . c e i l i n g s . ( I n t e r b u i l d , 1 9 6 7 ) . The world.'s f i r s t h i g h r i s e apartment, b u i l d i n g c l a d w i t h r e i n - . f o r c e d p l a s t i c s w a s . s t a r t e d i n Londonv E n g l a n d . i n 1965 ( B u i l d i n g s , 1968). P r o t e c t i v e P l a s t i c s L i m i t e d , , o f O n t a r i o , . i s r e p o r t e d . t o have s u c c e s s f u l l y m arketed a p r e f a b r i c a t e d b u i l d i n g u s i n g GRP sand w i c h p a n e l s w i t h a u r e -t h a n e foam c o r e ( F i n a n c i a l P o s t , 1 9 6 8 a ) . The same s o u r c e r e p o r t e d t h a t a B r i t i s h company has d e v e l o p e d a F R P - p a n e l l e d house w h i c h has-been • approved by l o c a l b u i l d i n g . a u t h o r i t i e s i n B r i t a i n . f o r l o w - r i s e h o u s i n g . T h i s p a n e l system has a l s o been approved f o r apartments and o f f i c e b u i l d -i n g s ; A l t h o u g h GRP p a n e l systems a r e n o t y e t c o m p e t i t i v e i n C a n a d i a n h o u s i n g , a c t i v e r e s e a r c h i n t h i s a r e a . i s c o n t i n u i n g . a n d new developments can be e x p e c t e d . A few o t h e r minor developments a r e a l s o w o r t h n o t i n g . . Runeberg (1969) i n d i c a t e d t h a t d oors e n t i r e l y o f . p l a s t i c have been r e p o r t e d and . t h a t PVC d o o r s a r e b e i n g p r o d u c e d I n . l a r g e q u a n t i t i e s i n b o t h West Ge r -many •and I t a l y . E x t r u d e d p r o f i l e p r o d u c t s s u c h as window.and door frames a r e r a p i d l y . i n f i l t r a t i n g t b i s t r a d i t i o n a l wood market i n Europe (Runeberg, 1969.).' Modern. P l a s t i c s (1968) has i n d i c a t e d t h a t . - p r o d u c t i o n . of. PV.C.window frames began i n t h e U.S. i n 1966 and., a l t h o u g h r e s i d e n t i a l homes have p r o -v i d e d t h e l a r g e s t , m a r k e t so f a r , t h i s p r o d u c t has been r e l a t i v e l y , u n s u c c e s s -f u l t o d a t e . A more r e c e n t C a n a d i a n d e v e l o p m e n t . i s a l a r g e . p o l y s t y r e n e loam, b l o c k d e s i g n e d t o a c t as t h e forms f o r t h e c o n c r e t e frame o f t h e house and as ..the . i n s u l a t i o n . ( C a n a d i a n B u i l d e r , 1969b). The b l o c k s a r e f i r s t a ssembled u s i n g a d h e s i v e s , r e i n f o r c i n g r o d s . a r e . p l a c e d i n p o s i t i o n , and t h e c o n c r e t e i s p o u r e d . A v a r i e t y o f s i d i n g s and i n t e r i o r f i n i s h e s may be u s e d . F e n n e l l (1969) r e p o r t e d t h a t houses have b e e n . e r e c t e d i n B a r r i e a n d O a k v i l l e , O n t a r i o . u s i n g t h e "Foam Form" s y s t e m , as w e l l as a townhouse complex i n L e a m i n g t o n , U n i v e r s a l S e c t i o n s L i m i t e d , a l a r g e O n t a r i o b u i l d e r , has a c q u i r e d 50 p e r c e n t o wnership of Foam.Form Canada L i m i t e d , . . w h i c h p l a n s t o b u i l d , a p l a n t t o produce t h e s e p l a s t i c u n i t s i n t h e T o r o n t o a r e a . I n O c t o b e r , 1969, a p l a s t i c s , house .was. e x h i b i t e d a t t h e P l a s t i c s Show of Canada i n T o r o n t o ( C a n a d i a n B u i l d e r , 1 9 6 9 c ) . U n l i k e most., p r e -v i o u s p l a s t i c s h o u s e s , i t was o f c o n v e n t i o n a l d e s i g n and u s e d p l a s t i c s t o r e p l a c e more c o n v e n t i o n a l m a t e r i a l s . . T h i s house, sponsored, by t h e Department of Trade.and Development of O n t a r i o , and t h e S o c i e t y of t h e P l a s t i c s I n d u s t r y , of Canada, was u s e d t o d e m o n s t r a t e o n l y t h o s e p l a s t i c p r o d u c t s w h i c h a r e i n c o m m e r c i a l p r o d u c t i o n and r e a d i l y a v a i l a b l e . . (Mat-e r i a l s o t h e r t h a n p l a s t i c s were employed where no p l a s t i c s u b s t i t u t e was a v a i l a b l e ) . Many of t h e s e p r o d u c t s s h o u l d i n t e r e s t wood p r o d u c t s manu-f a c t u r e r s : PVC s i d i n g , v i n y l f a s c i a and s o f f i t s , p l a s t i c f a c e d w a l l p a p e r , k i t c h e n c a b i n e t s of vacuum formed impact. s£yrene.and p o l y e s t e r , l a m i n a t e s , i r r a d i a t e d w o o d # p l a s t i c . f l o o r i n g , . PVC c e i l i n g p a n e l s , "Foam Form" w a l l s y s t e m ( d e s c r i b e d , above) epoxy-aggregate. w a l l , p a n e l s , , v i n y l , w a l l , cover-, i n g s , u r e t h a n e foam f i l l e d f r o n t d o o r , PVC f a c e d b i - f o l d c l o s e t d o o r s , s l i d i n g PVC and aluminum r e a r d o o r s , p o l y e t h y l e n e m o u l d i n g f o r door frames,. PVC-faced. gypsum b o a r d i n t e r i o r w a l l s , a bathroom w i t h FRP w a l l s , f l o o r a n d ' c e i l i n g , and PVC window .frames. That t h e s e p r o d u c t s . a r e commer-c i a l l y . a v a i l a b l e i n Canada i s . e v i d e n c e t h a t , p l a s t i c s m a n u f a c t u r e r s a r e becoming m a j o r c o n t e n d e r s i n t h e h o u s i n g m a r k e t , i f n o t so much f o r s t r u c t u r a l components, a t l e a s t f o r a n c i l l a r y p r o d u c t s r e l a t e d t o . i n t e r -i o r and e x t e r i o r . f i n i s h e s , and f o r a. w i d e v a r i e t y o f a c c e s s o r i e s . N o n - m e t a l l i c " M i n e r a l s T h i s group i n c l u d e s , s e v e r a l , d i f f e r e n t m a t e r i a l s i n c l u d i n g a s b e s -t o s , gypsum, c l a y ( b r i c k and t i l e ) and c o n c r e t e p r o d u c t s . A l t h o u g h grouped t o g e t h e r h e r e , e a c h i s u n l i k e t h e o t h e r s -with r e s p e c t . t o p r o p e r -t i e s and a r e a o f . a p p l i c a t i o n . A l t h o u g h a s b e s t o s p r o d u c t s a r e , t h e l e a s t u s e d of t h i s group i n r e s i d e n t i a l c o n s t r u c t i o n , a s b e s t o s cement s h i n g l e s , have been employed i n Canada a s . a . s i d i n g m a t e r i a l f o r many y e a r s . Bensons's (1968a) s t u d y of s i d i n g i n s i n g l e - f a m i l y d w e l l i n g s i n t h e U.S. i n d i c a t e d t h a t a s b e s t o s s h i n g l e s were u s e d on f o u r p e r c e n t o f the houses s u r v e y e d , w h i l e t h e A m e r i c a n Plywood A s s o c i a t i o n d i d n o t r e p o r t t h e . u s e of a s b e s t o s s i d i n g , a t a l l i n i t s s t u d y (Crow's F o r e s t P r o d u c t s D i g e s t , 1 9 7 0 ) , A l t h o u g h no . C a n a d i a n f i g u r e s a r e a v a i l a b l e , t h e use o f a s b e s t o s s i d i n g i n Canada i s a l s o r e l a t i v e l y low... P e r h a p s t h i s can be a c c o u n t e d f o r by a r e s u l t of a s u r v e y of h o u s i n g p e r f o r m a n c e w h i c h f o u n d t h a t . a s b e s t o s . c e m e n t s h i n g l e s . a r e f r e q u e n t l y b r o k e n o r c h i p p e d , . r e s u l t i n g i n u n s a t i s f a c t o r y , a p p e a r a n c e ( B u i l d I n t e r n a t i o n a l , 1970) . I t w o u l d appear t h a t t h i s p r o d u c t , i s n o t a m a j o r c o n t e n d e r f o r t h e r e s i d e n t i a l s i d i n g market and c o m p e t i t i o n f r o m . i t w i l l be l i m i t e d . The o n l y o t h e r use o f a s b e s t o s i n h o u s i n g i s as an i n -s u l a t i n g m a t e r i a l t o p r o v i d e adequate f i r e p r o t e c t i o n f o r s t e e l members i n m u l t i - f a m i l y d w e l l i n g s . On t h e w h o l e , a s b e s t o s doesn't compete s i g -n i f i c a n t l y w i t h wood m a t e r i a l s i n h o u s i n g a t t h e p r e s e n t t i m e , and i s n o t l i k e l y t o - i n t h e f u t u r e . S t u c c o (composed o f e i t h e r P o r t l a n d cement o r h y d r a t e d l i m e ) i s a n o t h e r m a t e r i a l w h i c h has been employed as an e x t e r i o r c l a d d i n g . B o t h Benson and-the "American Plywood A s s o c i a t i o n . r e p o r t e d t h a t s t u c c o was used i n e i g h t p e r c e n t o f t h e houses b u i l t i n the U.S. i n 1968. The use o f c r u s h e d g l a s s o f s t o n e embedded i n t h e s u r f a c e o f t e n p r o d u c e s an a t t r a c t i v e e x t e r i o r f i n i s h . C o n s i d e r e d a m a i n t e n a n c e - f r e e m a t e r i a l , s t u c c o w i l l p r o b a b l y r e m a i n p o p u l a r i n some r e g i o n s w i t h o u t a l t e r i n g i t s market s h a r e s i g n i f i c a n t l y . Gypsum has been u s e d i n t h e i n t e r i o r f i n i s h i n g o f d w e l l i n g s f o r many y e a r s and must be r e g a r d e d a s ' t h e t r a d i t i o n a l , m a t e r i a l i n t h i s a p p l i -c a t i o n . I t was once u s e d p r i m a r i l y assgypsum p l a s t e r and a p p l i e d t o i n -t e r i o r w a l l s o v e r wood l a t h and, more r e c e n t l y , m e t a l l a t h . O ther p l a s -t e r i n g m a t e r i a l s w h i c h have and s t i l l a r e b e i n g . e m p l o y e d a r e q u i c k l i m e ; h y d r a t e d l i m e , and i n o r g a n i c a g g r e g a t e s . These m a t e r i a l s have now l a r g e -l y been r e p l a c e d by gypsum w a l l b o a r d p a n e l s . c o n s i s t i n g o f a gypsum c o r e w i t h h e a vy paper f a c e s , c o m m o n l y . r e f e r r e d t o as " d r y w a l l " c o n s t r u c t i o n . I n 1955, t h i s w a l l b o a r d was u s e d i n . l e s s t h a n . 1 5 . p e r c e n t of. Canadian, d w e l l i n g s - u n i t s , b u t i n c r e a s e d t o about .50 p e r c e n t by 1965 (Hansen, 1965). U s i n g w a l l b o a r d i s more e c o n o m i c a l t h a n a p p l y i n g p l a s t e r and has t h e im^-p o r t a n t a d v a n t a g e s o f speed o f e r e c t i o n and b e i n g . l i t t l e a f f e c t e d by w i n t e r , w e a t h e r as opposed t o p l a s t e r w h i c h .is s l o w e r and more d i f f i c u l t t o a p p l y when c o l d . B o t h t h e d e c l i n i n g u s e o f p l a s t e r i n f a v o u r . o f w a l l b o a r d , and t h e i n c r e a s i n g use of m e t a l l a t h , have a l m o s t e l i m i n a t e d t h e use o f wood l a t h . I t c o u l d be a r g u e d t h a t . t h i s has been b a l a n c e d by t h e h i g h , volumes of paper u s e d as a . f a c i n g m a t e r i a l . o n w a l l b o a r d , Thus, a l t h o u g h t h e form o f wood p r o d u c t employed changed d r a s t i c a l l y , . t h e volume of wood-based m a t e r i a l r e q u i r e d . h a s . p r o b a b l y . n o t changed s i g n i f i c a n t l y . The use o f d e c o r a t i v e w a l l p a n e l s ( w h i c h has been d i s c u s s e d w i t h r e s p e c t t o g r a i n . p r i n t e d v i n y l o v e r l a y s ) . i n . d w e l l i n g s i s g e n e r a l l y , l i m i t e d t o s m a l l a r e a s s u c h as i n dens, l i v i n g rooms and r e c r e a t i o n rooms. A l t h o u g h t h e e x t e n t of use o f s u c h p a n e l s f l u c t u a t e s p e r i o d i c a l l y w i t h s t y l e t r e n d s and p e r s o n a l . t a s t e , t h e g e n e r a l p r e f e r e n c e i n l a r g e a r e a s i s f o r a smooth, . p a i n t a b l e s u r f a c e f r e e f r o m j o i n t s (Worth, 1957). P l a s t e r and w a l l b o a r d have t r a d i t i o n a l l y . p r o v i d e d s u c h a s u r f a c e e c o n o m i c a l l y . A t t e m p t s t o p r o -v i d e s u i t a b l e ;woodr-based p a n e l p r o d u c t s as an a l t e r n a t i v e t o w a l l b o a r d have n o t y e t been s u c c e s s f u l . On t h e o t h e r hand, a t r e n d toward a p p l y i n g v i n y l f i l m t o gypsum w a l l b o a r d f o r d e c o r a t i v e a p p l i c a t i o n s has a l r e a d y been n o t e d (Tane, 1967). I t has p r e v i o u s l y been i n d i c a t e d t h a t wood frame c o n s t r u c t i o n i s t h e t r a d i t i o n a l method of b u i l d i n g i n Canada.for b o t h s i n g l e - f a m i l y and m u l t i - f a m i l y , d w e l l i n g s up t o t h r e e . s t o r e y s . I f . 90 .per cent, of C a n a d i a n h o u s e s . u s e wood frame c o n s t r u c t i o n , as. i n d i c a t e d by t h e Department of Trade.and Commerce ( c a . 1 965), and i f t h i s f i g u r e a l s o a p p l i e s t o l o w - r i s e a p a r t m e n t s , t h e n a p p r o x i m a t e l y 10 p e r c e n t o f a l l d w e l l i n g s b u i l t i n . Canada up to t h r e e s t o r e y s a r e o f masonry ( p r i m a r i l y ) o r s o l i d c o n c r e t e c o n s t r u c t i o n . S i n c e d w e l l i n g s o v e r . t h r e e s t o r e y s e x c l u d e wood i n t h e b a s i c s t r u c t u r e , , the. q u e s t i o n o f t h e r e p l a c e m e n t o f wood s t r u c t u r a l components i n s u c h d w e l l i n g s has been l a r g e l y c o v e r e d i n t h e d i s c u s s i o n of t r e n d s toward h i g h - r i s e a p a r t m e n t s . L i t t l e was s a i d , about t h e m a t e r i a l s u s e d i n the b a s i c s t r u c t u r e s i n p l a c e o f wood. R e i n f o r c e d c o n c r e t e has been u s e d a l m o s t e x c l u s i v e l y i n t h e c o n s t r u c t i o n o f t h e l o a d , b e a r i n g w a l l s o f a p a r t -ments o v e r t h r e e s t o r e y s (Moreau and Van d e r Ryn, 1 9 6 7 ) . F o r r e a s o n s t h a t w i l l n o t be d e a l t w i t h h e r e , s t e e l s t r u c t u r a l frames w i t h c u r t a i n w a l l s have been employed s p a r i n g l y i n h i g h e r i s e a p a r t m e n t s . Due t o b u i l d i n g code r e g u l a t i o n s , u n i t masonry, c o n s t r u c t i o n has ( u n t i l . r e c e n t l y ) been e x c l u d e d f r o m l o a d b e a r i n g w a l l s i n .apartments o v e r t h r e e s t o r e y s . A r e v i s i o n o f the N a t i o n a l B u i l d i n g Code i n 1965, however,, has r e s u l t e d i n t h e use of masonry i n . h i g h - r i s e c o n s t r u c t i o n . ( F i n a n c i a l P o s t , 1968b). But s u c h developments do n o t a f f e c t t h e m a r k e t s f o r wood p r o d u c t s i n h o u s i n g . M a s o n r y . c o n s t r u c t i o n i n l o w - r i s e . h o u s i n g forms i n c l u d e s . t h o s e d w e l l i n g s i n .which t h e l o a d b e a r i n g w a l l s a r e composed of r e l a t i v e l y s m a l l u n i t s such.as s t o n e , c l a y b r i c k s , a n d ^ c o n c r e t e b l o c k s , cemented t o -g e t h e r by. m o r t a r . Masonry, i s u s e d i n both, s o l i d and c a v i t y w a l l s , the.: . l a t t e r h a v i n g t h e advantage o f p r o v i d i n g e x c e l l e n t p r o t e c t i o n a g a i n s t r a i n p e n e t r a t i o n ( R i t c h i e , 1 9 6 1 ) . The C a n a d i a n B r i c k Company.and.Dow C h e m i c a l o f . Canada L i m i t e d have t o g e t h e r r e c e n t l y d e v e l o p e d a c o m p l e t e masonry w a l l system w h i c h i s r e p o r t e d l y more e c o n o m i c a l t h a n c o n v e n t i o n a l masonry c o n s t r u c t i o n . I t i s . comprised, o f a b r i c k w a l l h e l d , i n p l a c e w i t h normal, b r i c k t i e s , t o w h i c h s h e e t s t y r o f o a m i n s u l a t i o n . i s glued,,.and gypsum w a l l b o a r d i s i n t u r n g l u e d t o t h e i n s u l a t i o n ( C a n a d i a n B u i l d e r , 1 9 6 8 ) . The use of b r i c k v e n e e r as an e x t e r i o r , c l a d d i n g i s more common i n Canada t h a n l o a d b e a r i n g masonry w a l l s . . A l t h o u g h C a n a d i a n s t a t i s t i c s a r e n o t a v a i l a b l e , ,Benson (1968a). found t h a t 28 p e r c e n t . o f houses c o n -s t r u c t e d i n t h e U.S. i n 1968 had b r i c k e x t e r i o r w a l l s . The A m e r i c a n P l y -wood A s s o c i a t i o n o b t a i n e d a c o r r e s p o n d i n g f i g u r e o f 43 p e r c e n t from i t s s u r v e y (Crow's F o r e s t P r o d u c t s D i g e s t , 1 9 7 0 ) . The r e a s o n f o r t h i s d i s c r e p -any i s n o t known, b u t i t may be r e a s o n a b l y assumed t h a t between.30 and.40 p e r c e n t o f C a n a d i a n houses a r e b u i l t w i t h a b r i c k e x t e r i o r . The use o f b r i c k . i s p r o b a b l y f o s t e r e d by ..bu i l d i n g codes and i n s u r a n c e r a t e s i n . l a r g e m e t r o p o l i t a n a r e a s s u c h as T o r o n t o and M o n t r e a l where f i r e codes a r e q u i t e s e v e r e . Benson has i n d i c a t e d t h a t t h e c o s t o f b r i c k w o r k ( i n s t a l l e d ) i s h i g h e r t h a n a l l . o t h e r e x t e r i o r c l a d d i n g s b u t . a l s o p o i n t e d o u t . t h a t t h i s i s n o t t h e d e c i d i n g f a c t o r i n most c a s e s . There i s l i t t l e e v i d e n c e t h a t masonry i s making i n r o a d s a g a i n s t wood frame c o n s t r u c t i o n i n housing.. Most o f t h e r e c e n t developments i n . , masonry c o n s t r u c t i o n r e l a t e t o t h e p r e f a b r i c a t i o n o f p a n e l s of. b r i c k . . These w i l l , be d i s c u s s e d i n r e f e r e n c e t o i n d u s t r i a l i z e d b u i l d i n g . The u s e of c o n c r e t e has b e e n . b r i e f l y n o t e d as a s t r u c t u r a l s y s t e m f o r h o u s i n g . A l t h o u g h i t f i n d s i t s major, a p p l i c a t i o n i n . a partments above . t h r e e s t o r e y s , . i t has fo u n d l i m i t e d u s e , i n s i n g l e - f a m i l y h o u s e s . a n d . l o w -r i s e d w e l l i n g s . • T w o . r e c e n t l y d e v e l o p e d c o n c r e t e house s y s t e m s . w i l l be b r i e f l y o u t l i n e d t o d e m o n s t r a t e t h e i m a g i n a t i v e . e f f o r t s b e i n g made w i t h t h i s m a t e r i a l , , K e t t l e ( 1 9 6 8 ) . d e s c r i b e d a d e m o n s t r a t i o n house b u i l t i n G a i t , O n t a r i o i n . 1 9 6 8 . Curved m e t a l f o r m s , p l a s t i c . I n s u l a t i o n and.a m e t a l mesh were e r e c t e d i n one day t o form t h e b a s i c s t r u c t u r e . C o n c r e t e was t h e n s p r a y e d oriitthe f o l l o w i n g day t o complete t h e w a l l system.. A.second s y s t e m ( p r e v i o u s l y o u t l i n e d w i t h r e s p e c t t o foamed p l a s t i c s ) u t i l i z e s - l a r g e p o l y s t y r e n e foam b l o c k s i n t o w h i c h c o n c r e t e i s poured in..situ, a f t e r a s s e m b l i n g t h e .foam b l o c k s (Canadian. B u i l d e r . , 1969b). A number.of houses have a l r e a d y been b u i l t and t h e sy s t e m i s now b e i n g c o m m e r c i a l i z e d . A l t h o u g h t h e s e a r e i n t e r e s t i n g . b u i l d i n g i n n o v a t i o n s , . t h e m a j o r developments i n h o u s i n g u s i n g c o n c r e t e i s , i n t h e a r e a o f p r e - s t r e s s e d and p r e c a s t c o n c r e t e components f o r use i n m u l t i - f a m i l y . s t r u c t u r e s . . . Since,, t h e s e developments a r e c l o s e l y l i n k e d w i t h i n d u s t r i a l i z e d b u i l d i n g , t h e y w i l l be d i s c u s s e d b e l o w i n c o n n e c t i o n w i t h t h i s t o p i c . Combined M a t e r i a l s A l t h o u g h t h e r e has been g r e a t i n t e r e s t i n r e c e n t y e a r s i n t h e c o n c e p t o f u s i n g c o m b i n a t i o n s o f m a t e r i a l s , w i t h t h e o b j e c t i v e o f e x p l o i t -i n g t h e d e s i r a b l e p r o p e r t i e s of e a c h i n the f i n a l . p r o d u c t , . t h e i d e a i s . b y no means a new one. A number of w e l l a c c e p t e d c o m b i n a t i o n s have been i n . use f o r many y e a r s . P a i n t s a p p l i e d t o . v a r i o u s m a t e r i a l s t o r e d u c e . c o r r o -s i o n and. i mprove appearance i s p r o b a b l y one. of t h e o l d e s t combinations... P erhaps a more s o p h i s t i c a t e d one i s . r e i n f o r c e d c o n c r e t e i n . w h i c h ,the s t e e l rods p r o v i d e h i g h t e n s i l e s t r e n g t h to.complement t h e h i g h c o m p r e s s i v e s t r e n g t h o f the. c o n c r e t e ; a t t h e same t i m e t h e s e m a t e r i a l s a r e c o m p a t i b l e w i t h r e s p e c t t o o t h e r p r o p e r t i e s . The " c o m b i n i n g o f m a t e r i a l s " i n c o n s t r u c t i o n can be r e g a r d e d i n two ways: (1) t h e i n t i m a t e m a t i n g o f two o r more m a t e r i a l s i n a s i n g l e component p r o d u c t ; and (2) t h e use o f two o r more s i n g l e - p r o d u c t compo^-n e n t s ; i n b o t h c a s e s the m a t e r i a l s a r e r a t i o n a l l y chosen on p e r f o r m a n c e and p r i c e c r i t e r i a . The f i r s t o f t h e s e two a s p e c t s w i l l f i r s t be d i s -c u s s e d w i t h r e s p e c t t o c o m b i n a t i o n p r o d u c t s p r e s e n t l y used i n r e s i d e n -t i a l c o n s t r u c t i o n . Throughout the d i s c u s s i o n s o f s t e e l , aluminum, p l a s t i c s and non^-m e t a l l i c m i n e r a l p r o d u c t s , f r e q u e n t r e f e r e n c e was made t o p r o d u c t s w h i c h a r e a c t u a l l y c o m b i n a t i o n s o f m a t e r i a l s . S t e e l and aluminum s i d i n g w i t h p o l y v i n y l f l u o r i d e and o t h e r h i g h l y p r o t e c t i v e p l a s t i c c o a t i n g s were m e n t i o n e d . P l a s t i c foam san d w i c h p a n e l s w i t h m e t a l - f a c e s , and - aluminums-f a c e d wood s i d i n g a r e f u r t h e r examples o f m e t a l s i n c o m b i n a t i o n w i t h o t h e r m a t e r i a l s . P l a s t e r on wood l a t h o r m e t a l l a t h , and paper f a c i n g on gypsum w a l l b o a r d a r e examples from t h e n o n - m e t a l l i c m i n e r a l s group. A l a r g e number o f w o o d - p l a s t i c c o m p o s i t e s a r e p r e s e n t l y used i n c o n s t r u c -t i o n . These i n c l u d e u r e a and p h e n o l i c r e s i n s i n plywood and p a r t i c l e b o a r d , h i g h - p r e s s u r e p l a s t i c l a m i n a t e s on wood, v i n y l - f a c e d wood composi^-t i o n b o a r d s , p h e n o l i c i m p r e g n a t e d p a p e r o v e r l a y s , and i r r a d i a t e d wood-r--p l a s t i c p a r q u e t f l o o r i n g . The e x t e n t t o w h i c h t h e s e p r o d u c t s a r e employed has a l r e a d y been i n d i c a t e d where t h i s i n f o r m a t i o n i s a v a i l a b l e . One n o t a b l e f e a t u r e about t h e c o m b i n a t i o n p r o d u c t s m e n t i o n e d above i s the r h i g h i n c i d e n c e o f p l a s t i c s among them. T h i s i s not a c o i n c i d e n c e b u t r a t h e r a r e f l e c t i o n o f the a b i l i t y o f v a r i o u s p l a s t i c s t o p r o v i d e p r o p e r t i e s w h i c h a r e e i t h e r l a c k i n g o r d e f i c i e n t i n t h e m a t e r i a l s w i t h w h i c h t h e y a r e combined, p r i m a r i l y m e t a l s and wood. O u t s t a n d i n g among t h e s e p r o p e r t i e s a r e c o r r o s i o n and i m p a c t r e s i s t a n c e , w a t e r r e s i s t a n c e , d u r a b i l i t y , and a e s t h e t i c c h a r a c t e r i s t i c s o f v a r i o u s p l a s t i c s which, make them i d e a l l y s u i t e d f o r a wide v a r i e t y o f c o a t i n g s and c o v e r i n g s on many m a t e r i a l s . That wood can be combined s u c c e s s f u l l y w i t h p l a s t i c s has a l -ready been d e m o n s t r a t e d . I t would a p p e a r , however, t h a t t h e r e l a t i v e l y h i g h p r i c e s o f p l a s t i c s has been a l i m i t i n g f a c t o r i n s o m e ' i n s t a n c e s , a s i t u a t i o n w h i c h w i l l l i k e l y improve i n t h e f u t u r e . A l t h o u g h p l a s t i c s have been the most used m a t e r i a l i n c o m b i n a t i o n w i t h wood, a few p r o d u c t s u s i n g c o m b i n a t i o n s o f m e t a l s w i t h wood have been m a r k e t e d . The r e l a t i v e i n f r e q u e n c y o f t h e s e c o m b i n a t i o n s Cas opposed t o w o o d - p l a s t i c c o m b i n a t i o n s ) i s p r o b a b l y due t o a n a r r o w e r range o f p o s - s i b i l a -i t i e s o f p r o d u c t improvement by so d o i n g , and fewer p o s s i b l e ways o f physi-r-c a l l y c o m b i n i n g t h e s e m a t e r i a l s . N o n - m e t a l l i c m i n e r a l p r o d u c t s a l s o appear t o o f f e r fewer p o s s i b i l i t i e s f o r j o i n t use w i t h wood f o r t h e r e a s o n s n o t e d a b o v e ' f o r m e t a l s . I n summary, i t must be c o n c l u d e d t h a t wood can be used s u c c e s s f u l l y i n combined p r o d u c t s , and t h a t w o o d - p l a s t i c c o m b i n a t i o n s o f f e r a p a r t i c u -l a r l y a t t r a c t i v e avenue o f p r o d u c t development f o r t h e f o r e s t i n d u s t r i e s . I t i s g e n e r a l l y acknowledged t h a t t h e e r a of combined m a t e r i a l s i s now h e r e . As i n d i c a t e d , c o m b i n a t i o n s can be r e a l i z e d i n two d i f f e r e n t ways: (1) t h e j o i n i n g o f two m a t e r i a l s i n one p r o d u c t ; and C2) t h e use of two o r more s i n g l e p r o d u c t components. The f i r s t o f t h e s e two a s p e c t s has a l r e a d y been d i s c u s s e d . The second a s p e c t o f c o m b i n i n g m a t e r i a l s i m p l i e s t h a t a l l mater-, i a l s m a n u f a c t u r e r s s h o u l d be c o m p l e t e l y r a t i o n a l w i t h r e s p e c t t o the p r o -d u c t s t h e y m a n u f a c t u r e , and n o t attempt t o market and p r o m o t e ' p r o d u c t s w h i c h a r e n o t s u i t a b l e f o r a s p e c i f i c use. T h i s r e q u i r e s an acknowledge-ment of the s h o r t c o m i n g s and advantages o f each m a t e r i a l , and t h e admis-s i o n t h a t a competing m a t e r i a l may be more s a t i s f a c t o r i l y employed i n a g i v e n a p p l i c a t i o n . There a r e many i n s t a n c e s i n w h i c h each p r o d u c t has c e r t a i n d i s a d v a n t a g e s , and the c h o i c e i s m a i n l y s u b j e c t i v e ' and based on consumer p r e f e r e n c e . The p r o m o t i o n o f p r o d u c t s w h i c h o b v i o u s l y have poor p e r f o r m a n c e c h a r a c t e r i s t i c s r e l a t i v e t o competing p r o d u c t s , or w h i c h f r e q u e n t l y res-s u i t i n c o m p l a i n t s from consumers, p r o b a b l y does more harm i n t h e l o n g r u n t h r o u g h weakening the consumers' c o n f i d e n c e i n t h e m a t e r i a l t h a n the s h o r t - r u n s a l e s r e v e n u e s j u s t i f y . How t h i s l i n e o f - r e a s o n i n g w i l l a f f e c t th e f o r e s t i n d u s t r i e s i s perhaps d e b a t a b l e . I t may s i g n i f y a r e c o g n i t i o n t h a t wood p r o d u c t s , w h i c h have been so w i d e l y employed i n h o u s i n g i n t h e p a s t , can no l o n g e r be e x p e c t e d t o command such a l a r g e s h a r e o f t h e r e s i ^ -d e n t i a l c o n s t r u c t i o n m a r k e t , g i v e n new m a t e r i a l s and p r o d u c t s w h i c h p r o -v i d e s u p e r i o r p e r f o r m a n c e . I t d e f i n i t e l y i m p l i e s t h a t funds would be b e t t e r s p e n t on r e s e a r c h t o overcome the d e f i c i e n c i e s o f wood i n s p e c i e f i c u s es r a t h e r t h a n on p r o m o t i n g i n f e r i o r p r o d u c t s . The u n d e r l y i n g t a c i t a d m i s s i o n t h a t wood p r o d u c t s cannot p r o v i d e a l l t h e r e q u i r e d funcs-t i o n s i n s p e c i f i c end uses s h o u l d p o i n t to a need f o r g r e a t e r R & D e f f o r t t o d e v e l o p more s u i t a b l e p r o d u c t s , u s i n g o t h e r m a t e r i a l s where t h e i r p r o -p e r t i e s a r e r e q u i r e d t o complement t h o s e o f wood. A l t h o u g h t h i s a p p r o a c h w i l l l e a d t o a r e d u c t i o n i n the co n s u m p t i o n o f wood i n t h o s e p r o d u c t s w h i c h have been produced e n t i r e l y of wood i n the p a s t , i t i s e a s i l y appre^-' c i a t e d t h a t t h i s i s s t i l l a more r a t i o n a l p r o p o s a l t h a n a t t e m p t i n g t o corns p e t e w i t h a l e s s d e s i r a b l e p r o d u c t and r i s k i n g t he l o s s o f an e n t i r e mar*-k e t . INDUSTRIALIZED BUILDING Much has been w r i t t e n o v e r t h e p a s t decade about i n d u s t r i a l i z e d b u i l d i n g and i t s i m p l i c a t i o n s f o r t h e b u i l d i n g i n d u s t r y . Many European c o u n t r i e s a r e a l r e a d y a c t i v e l y e n g a g e d . i n f a c t o r y p r o d u c t i o n . o f h o u s i n g u n i t s . o r t h e i r components w h i c h a r e s h i p p e d t o t h e b u i l d i n g s i t e f o r a s sembly. The systems of f a c t o r y - b u i l t h o u s e s . d e v e l o p e d i n Europe have, been p r i m a r i l y , m u l t i - f a m i l y s t r u c t u r e s o f c o n c r e t e , some of w h i c h have been r e c e n t l y i n t r o d u c e d t o N o r t h A m e r i c a . However, developments i n s y s t e m s . b u i l d i n g i n d i g e n o u s t o t h i s c o n t i n e n t have no t been l a c k i n g , b u t have been g r a d u a l l y e v o l v i n g o v e r a number o f y e a r s . I t i s t h e g e n e r a l concensus o f o p i n i o n among a u t h o r i t i e s on t h i s s u b j e c t , t h a t i n d u s t r i a l -i z e d b u i l d i n g w i l l c o n t i n u e t o e v o l v e , and a l t h o u g h i t w i l l n o t r e p l a c e t r a d i t i o n a l c o n s t r u c t i o n methods e n t i r e l y , i t may become a major, f a c t o r i n t h e r e s i d e n t i a l , c o n s t r u c t i o n i n d u s t r y , p a r t i c u l a r l y where h i g h volume, r e p e t i t i v e s t r u c t u r e s a r e r e q u i r e d . I t w o u l d t h e r e f o r e be a p p r o p r i a t e t o a s s e s s i t s i m p l i c a t i o n s w i t h , r e s p e c t t o m a t e r i a l s . r e q u i r e m e n t s i n an e f f o r t t o d e t e r m i n e t h e e f f e c t s , i t w i l l l i k e l y have on wood p r o d u c t s mar-k e t s . A b r i e f o u t l i n e of some i m p o r t a n t a s p e c t s of i n d u s t r i a l i z e d b u i l d i n g i s i n o r d e r t o p l a c e t h e s u b j e c t i n p e r s p e c t i v e . The r a t i o n a l e b e h i n d f a c t o r y p r o d u c t i o n of components ( o r whole h o u s i n g u n i t s ) , w h i c h . a r e t h e n s h i p p e d t o t h e s i t e f o r f i n a l . a s s e m b l y o r e r e c t i o n , l i e s i n c e r -t a i n economies w h i c h ca n be r e a l i z e d . These; i n c l u d e h i g h e r volume p r o d u c -t i o n , w i t h r e s u l t a n t economies o f s c a l e s u c h as b u l k p u r c h a s i n g , t h e s u b -s t i t u t i o n o f l e s s s k i l l e d , f a c t o r y - t y p e l a b o u r f o r s k i l l e d o n - s i t e l a b o u r , i mproved ..working c o n d i t i o n s which, e l i m i n a t e o r reduc e many d i f f i c u l t i e s i m p l i c t I n c o n v e n t i o n a l o n - s i t e c o n s t r u c t i o n , , c o n s i s t e n t h i g h q u a l i t y p r o d u c t i o n , and f a s t e r b u i l d i n g t i m e w h i c h s h o r t e n s t h e p e r i o d , i n w h i c h c a p i t a l i s t i e d up (Webb and L e g g e t , 1 9 6 7 ) . McMeekin (1966) has i n d i c a t e d t h a t much of t h e c o s t . s a v i n g s o f i n d u s t r i a l i z e d b u i l d i n g i s due t o i n d i r e c t f a c t o r s r e s u l t i n g from t h e i m -p o s i t i o n o f c e r t a i n . . d i s c i p l i n e s on t h e whole b u i l d i n g . o p e r a t i o n : p r e -p l a n n i n g , s t a n d a r d i z e d members, p r e f e r r e d d i m e n s i o n s , r e p e t i t i o n , and more p r e c i s e c o n t r o l and s c h e d u l i n g .of o p e r a t i o n s . He s u g g e s t s t h a t t h e s e a r e a s p e c t s o f b u i l d i n g w h i c h c o u l d a l s o be a p p l i e d t o c o n v e n t i o n a l o n - s i t e c o n s t r u c t i o n w i t h r e s u l t i n g economic g a i n s ; and t h a t t h e . g r o w t h o f i n d u s t r i a l i z e d b u i l d i n g w i l l i n f a c t i n d u c e s u c h " r a t i o n a l i z a t i o n " o f n o r -mal o n - s i t e c o n s t r u c t i o n . On t h e n e g a t i v e s i d e , a h i g h c a p i t a l o u t l a y i s r e q u i r e d f o r a f a c t o r y and t h e n e c e s s a r y e r e c t i o n equipment, and i n o r d e r t o r e c o v e r t h e i n v e s t m e n t , a l l equipment must be c o n t i n u o u s l y p r o d u c t i v e , t h u s n e c e s s i -t a t i n g a c o n c e n t r a t e d market a r e a (McMeekin, 1966). The . f a c t o r y may be e i t h e r f i x e d o r m o b i l e , depending on the. c o n c e n t r a t i o n , o f . w o r k . I t has been r e p o r t e d t h a t t h e r e s u l t i n g monetary s a v i n g i n . a c t u a l i n - p l a c e c o s t i s o f t e n s m a l l o r n o n - e x i s t e n t (Webb and L e g g e t , 1 9 6 7 ) . N e v e r t h e l e s s , some European systems do c l a i m a 10. to.20 p e r c e n t s a v i n g s over, t r a d i t i o n a l methods p l u s an a d d i t i o n a l f i v e p e r cent, t h r o u g h . s h o r t e n e d , c o n s t r u c t i o n f i n a n c i n g ( P l a t t s , 1968a). C l a s s e s of I n d u s t r i a l i z e d B u i l d i n g D i f f e r e n t degrees of. i n d u s t r i a l i z e d b u i l d i n g , can be. r e c o g n i z e d , v depending on t h e amount of work a c t u a l l y , p e r f o r m e d i n t h e f a c t o r y : (a) o n - s i t e c o n s t r u c t i o n w i t h t h e employment of some f a c t o r y ^ b u i l t components; (b) component packages m a n u f a c t u r e d i n a p l a n t and s h i p p e d t o t h e s i t e f o r assembly ( e x c l u d i n g i n t e r i o r f i n i s h -i n g ) ; (c) t h e m a n u f a c t u r e o f complete h o u s i n g u n i t s i n one or s e v e r a l s e c t i o n s ( i n c l u d i n g i n t e r i o r , f i n i s h i n g ) , r e q u i r -i n g o n l y f i n a l e r e c t i o n , c o u p l i n g o f t h e s e c t i o n s , and h o o k i n g up of u t i l i t i e s . . The f i r s t o f t h e s e i s t h e f o r m t h a t has e v o l v e d i n t h e house b u i l d i n g i n d u s t r y o v e r t h e p a s t decade o r more i n Canada, and i s now v e r y common. I n 1968 i t was r e p o r t e d t h a t o v e r 90 p e r c e n t of a l l house b u i l d -e r s i n Canada were u s i n g p r e - b u i l t components.in some fo r m ( F i n a n c i a l P o s t , 1 9 6 8 c ) . T h i s has been p r i m a r i l y i n s i n g l e - and t w o — f a m i l y h o u s e s , w h i l e m u l t i - f a m i l y wood frame d w e l l i n g s have employed components a l s o , b u t to a l e s s e r e x t e n t . The second form has been adopted t o a l e s s e r y e t s i g n i f i c a n t ex-t e n t i n Canada, and i s e x e m p l i f i e d by house packages o f wood frame c o n s t r u c -t i o n . I t was r e c e n t l y r e p o r t e d t h a t 20 p e r cent of t h e C a n a d i a n market f o r s i n g l e - f a m i l y d w e l l i n g s i s a c c o u n t e d f o r by b o t h packages o f f a c t o r y - m a d e components ( M a t h i a s , . 1 9 6 9 ) . Most o f t h e . E u r o p e a n systems d e v e l o p e d a l s o b e l o n g i n t h i s c a t e g o r y . The f i n a l c a t e g o r y , s e c t i o n a l h o u s i n g , i s . t h e most, advanced form of f a c t o r y - b u i l t d w e l l i n g u n i t s . T h i s t y p e o f d w e l l i n g has o n l y been man-u f a c t u r e d t o a v e r y l i m i t e d e x t e n t , e i t h e r i n Europe o r i n N o r t h A m e r i c a . (Although, m o b i l e homes a r e o f t e n c o n s i d e r e d . i n t h i s , c a t e g o r y , t h e codes w h i c h r e g u l a t e s t h e i r c o n s t r u c t i o n a r e n o t b u i l d i n g codes, and t h e y w i l l n o t be c o n s i d e r e d h e r e . I t i s r e a s o n a b l e t o assume t h a t t h e appearance and c o s t s t r u c t u r e of m o b i l e homes; b u i l t t o b u i l d i n g code s t a n d a r d s , would be v e r y s i m i l a r t o t h a t o f f a c t o r y - p r o d u c e d s e c t i o n a l , houses.) A v a r i a n t o f c o m p l e t e l y f i n i s h e d d w e l l i n g u n i t s i s t h e p r o d u c t i o n o f com-p l e t e l y f i n i s h e d c o r e u n i t s (bathrooms and k i t c h e n s ) , i n w h i c h a l l plumb-i n g and u t i l i t i e s a r e i n s t a l l e d i n t h e f a c t o r y and t h e u n i t , p u t - i n . p l a c e as a component a t t h e b u i l d i n g s i t e . T h e s e . a r e p r e s e n t l y b e i n g p r o d u c e d b o t h i n . E u r o p e , a n d i n N o r t h A m e r i c a . The development of i n d u s t r i a l i z e d h o u s i n g i n Canada, and some' o f t h e more r e c e n t developments i n t h i s area., a r e d i s c u s s e d b e l o w , em-p h a s i z i n g t h o s e a s p e c t s w h i c h - b e a r on t h e q u e s t i o n of t y p e o f m a t e r i a l s employed. O n - s i t e B u i l d i n g W i t h L i m i t e d Use of Components The i n c r e a s i n g use. o f components i n t r a d i t i o n a l o n - s i t e construc--t i o n has been an i m p o r t a n t f a c t o r i n h o l d i n g down .the p r i c e s of s i n g l e -f a m i l y houses i n Canada. D i c k e n s (1969) has i n d i c a t e d t h a t , , o v e r t h e 1949-65 p e r i o d , t h e c o s t s of m a t e r i a l s and l a b o u r i n c r e a s e d by 51. and 136 p e r c e n t , r e s p e c t i v e l y , w h i l e house c o n s t r u c t i o n c o s t s .rose b y . o n l y . 4 4 . p e r -c e n t . He a l s o c i t e d a s t u d y , o f a t y p i c a l s i t e - b u i l t house c a r r i e d o u t . i n 1965.by t h e D i v i s i o n of B u i l d i n g R e s e a r c h (NRC), I t was.found..that s i t e l a b o u r c o n s t i t u t e d o n l y 24 per c e n t of o n - s i t e c o s t s as opposed t o 40 to. 50 p e r c e n t once commonly assumed, a r e f l e c t i o n of t h e I n c r e a s i n g use of components. The use o f components i n house c o n s t r u c t i o n has been p r o c l a i m e d t h e most w i d e l y , a c c e p t e d i n n o v a t i o n i n . t h i s i n d u s t r y ( R i c h , 1965). Employ-i n g them r e d u c e s o n - s i t e and t o t a l c o n s t r u c t i o n t i m e , r e d u c e s t h e need f o r h i g h l y - p a i d t r adesmen, and r educes m a t e r i a l , w a s t e . Components r e c e i v e d on t h e s i t e r e a d y f o r i n s t a l l a t i o n i n c l u d e p r e - f i t windows, k i t c h e n c a b i -n e t s , pre-hung d o o r s , p r e - f i n i s h e d p a n e l l i n g , and r o o f t r u s s e s , . a s w e l l as o t h e r i t e m s (McCance, 1969a). The advantage which, o n - s i t e b u i l d e r s have (whether u s i n g components o r n o t ) i s t h e a b i l i t y t o i n c r e a s e o r de-c r e a s e . p r o d u c t i o n w i t h m i n i m a l d i s r u p t i o n of t h e o p e r a t i o n , as opposed t o t h e p r o d u c e r of f a c t o r y - b u i l t houses who r e l i e s on a s t e a d y volume of b u s i n e s s (McCance, 1969a). I t i s g e n e r a l l y a g r e e d t h a t components w i l l . c o n t i n u e t o p l a y an i n c r e a s i n g r o l e i n . o n - s i t e wood frame r e s i d e n t i a l c o n s t r u c t i o n , w i t h h i g h e r p r i c e d and custom b u i l t d w e l l i n g s r e t a i n i n g t h e h i g h e s t degree of t r a d i t i o n a l o n - s i t e c o n s t r u c t i o n methods. P r e f a b r i c a t e d Component Packages The c o n c e p t of u s i n g wood f r a m e . c o n s t r u c t i o n f o r " f a c t o r y - b u i l t " o r " p r e f a b r i c a t e d " house packages i s n o t new, t h e i n i t i a l a t t e m p t s h a v i n g been made i n t h e m i d d l e 1920's ( P l a t t s , 1964b). Emergency h o u s i n g and' v e t e r a n s ' h o u s i n g , d u r i n g .and i m m e d i a t e l y f o l l o w i n g . W o r l d War I I , . f o l l o w e d b y summer c o t t a g e s , w e r e . t h e f o r e r u n n e r s o f t o d a y ' s wood frame f a c t o r y -b u i l t packaged h o u s e s . P l a t t s ' (1964b) d e f i n i t i o n of a " p r e f a b r i c a t e d h o u s e" — a house w h e r e i n . p r e f a b r i c a t e d components compose'at l e a s t t h e m a j o r p o r t i o n . o f . t h e house s h e l l . — w i l l b e used h e r e . F o r a. number of y e a r s , t h e t y p i c a l s u p p l i e r of house packages was an "open-market p r e f a b -r i c a t o r " who s o l d l a r g e l y t o o w n e r - b u i l d e r s i n r u r a l a r e a s . Around.1956-59, more i n t e n s i v e p r e f a b r l c a t i o n began with., t h e e n t r y o f " p r o j e c t p r e f a b r i -c a t o r s " who m a n u f a c t u r e house:packages f o r . t h e i r own p r o j e c t s on d e v e l o p e d l a n d . ( P l a t t s , 1964b). The u s e . o f house p a c k a g e s . i s r e p o r t e d .to have i n -c r e a s e d f r o m t h r e e p e r c e n t ( o f s i n g l e - f a m i l y , houses) i n 1957, to. 15 per c e n t i n 1964, t o 20 p e r c e n t a t the. p r e s e n t t i m e . ( F i n a n c i a l P o s t , 1970a). A l t h o u g h , wood frame p r e f a b r i c a t i o n shops do not. use advanced, t e c h -n o l o g y o r a h i g h degree o f automation., i t i s c l a i m e d t h a t t h e p r o d u c t i v i t y o f l a b o u r can be d o u b l e d by b r i n g i n g t h e .worker i n s i d e , s u p e r v i s i n g him, and k e e p i n g m a t e r i a l s and j o b s o r g a n i z e d and. a t = hand ( P l a t t s , 1964b) . D i c k e n s . ( 1 9 6 9 ) has s t a t e d t h a t t h e wood.frame system i s n o t r e a d i l y amen-a b l e t o h i g h l y mechanized p r o d u c t i o n . (due t o t h e number, o f p i e c e s and v a r -i a b i l i t y o f m a t e r i a l ) and t h a t t h e p r o d u c t i v i t y g a i n s of p r e f a b r i c a t o r s i n Canada has been p r i m a r i l y a c h i e v e d t h r o u g h s h e l t e r e d , o r g a n i z e d - w o r k i n g c o n d i t i o n s , r a t h e r t h a n m e c h a n i z a t i o n . .. He has a l s o c l a i m e d t h a t w i t h a shop l a b o u r c o n t e n t . o f 15 t o 30 per .cent ( a l r e a d y common i n Canada), f u r -t h e r s t a g e s o f p r e f a b r i c a t i o n do n o t a u t o m a t i c a l l y b r i n g a d d i t i o n a l l a b o u r s a v i n g s u s i n g the wood frame s y s t e m . The i m p l i c a t i o n .here i s t h a t , h i g h e r l e v e l s o f p r e f a b r i c a t i o n . m a y n o t be p r a c t i c a b l e f o r wood frame c o n s t r u c -t i o n , w i t h t h e r e s u l t t h a t i n n o v a t i o n s i n systems b u i l d i n g w h i c h a r e a d a p t -a b l e t o a h i g h e r l e v e l o f p r e f a b r i c a t i o n , may e v e n t u a l l y p r o v i d e s i g n i f i s -c a n t c o m p e t i t i o n . f o r . t h e wood frame system. T h i s v i e w p o i n t ( h e l d , b y t h e D i v i s i o n of B u i l d i n g R e s e a r c h , NRC)..is opposed, by. s u p p o r t e r s , of .the c o n -cept..of s e c t i o n a l houses of wood frame c o n s t r u c t i o n . The D i v i s i o n o f B u i l d i n g R e s e a r c h c l a i m s t h a t . s i g n i f i c a n t s a v i n g s a r e o n l y a t t a i n a b l e by . p r e f a b r i c a t i n g . t h e completed,, p r e - f i n i s h e d s h e l l and c a b i n e t r y , and a t l e a s t some s e r v i c e s . . However, t h e w i n t e r : b u i l d i n g a d v a n t a g e , f a s t t u r n o v e r , c o n t r o l of. c o s t s , .time.and. q u a l i t y a r e s a i d t o be as i m p o r t a n t as c o s t r e d u c t i o n ( P l a t t s , 1964b). T r a n s p o r t a t i o n c o s t s u s u a l l y l i m i t t h e s e l l i n g .radius t o 200 to. 350 m i l e s f r o m t h e f a c t o r y . I t i s s i g n i f i c a n t t h a t . p r e f a b r i c a t o r s a r e a d a p t i n g t h e i r .systems to. i n c l u d e m u l t i - f a m i l y u n i t s w h i c h can e a s i l y , be used i n t h r e e - s t o r e y , m u l t i p l e h o u s -i n g . \ T h i s r e q u i r e s t h e i n t r o d u c t i o n of s p e c i a l h a n d l i n g equipment s u c h as. t r u c k - m o u n t e d . c r a n e s ( P l a t t s , 1964b). I t was c o n c l u d e d . b y . D i c k e n s (1969) t h a t wood frame c o n s t r u c t i o n w i l l r e m a i n . d i f f i c u l t f o r p r o p o s e d i n n o v a t i o n s t o e q u a l i n b o t h c o s t and q u a l i t y . He a l s o c o n c l u d e d t h a t t h e p r o v e n e f f i c i e n c y of p r e f a b r i c a t e d wood frame systems s h o u l d . r e s u l t i n t h e i r c o n t i n u e d w i d e use I n both, s i n g l e - f a m i l y d w e l l i n g s and c e r t a i n l o w - r i s e forms of m u l t i p l e h o u s i n g . S e c t i o n a l House C o n s t r u c t i o n The u l t i m a t e i n I n d u s t r i a l i z e d h o u s i n g i s t h e " s e c t i o n a l . " house i n w h i c h t h e e x t e r i o r . a n d i n t e r i o r o f t h e h o u s e . . ( o r , d w e l l i n g u n i t f o r . m u l t i p l e s t r u c t u r e s ) i s c o m p l e t e l y f i n i s h e d , i n .the..factory and o n l y re-r q u i r e s t r a n s p o r t a t i o n of t h e s e c t i o n s t o t h e b u i l d i n g s i t e , t h e j o i n i n g , o f t h e s e c t i o n s i n p l a c e , and c o n n e c t i n g of u t i l i t i e s . U n t i l " t h e . p r e s e n t t i m e . t h i s method h a s n o t b e e n . w i d e l y adopted b u t . t h e c o n c e p t h a s . r o u s e d much i n t e r e s t . I n . t h e c a s e of t r a n s p o r t a b l e . s e c t i o n s , , t h e a d d i t i o n a l s a v i n g s t h r o u g h a p p r o a c h i n g .100 p e r c e n t ..shop l a b o u r have to. b e - b a l a n c e d a g a i n s t t h e much.higher, t r a n s p o r t a t i o n c o s t s o f m o v i n g . t h e s e c t i o n s t o t h e s i t e , t h e l a r g e r p l a n t r e q u i r e d . , p l u s t h e c o s t o f heavy equipment t o l i f t t h e s e c t i o n s i n t o p l a c e . The p o s i t i o n t a k e n by t h e D i v i s i o n o f B u i l d i n g R e s e a r c h (NRC) i s t h a t , w i t h wood frame s y s t e m s , the. g a i n s a c h i e v e d by p r o d u c i n g s u c h f i n i s h e d house s e c t i o n s a r e n e g l i g i b l e i f they e x i s t a t a l l ( P l a t t s , 1964b). The i d e a o f p r o d u c i n g houses i n complete t r a n s p o r t a b l e s e c -t i o n s i s n o t new i n Canada, t h e f i r s t s u c h v e n t u r e d a t i n g b a c k . t o t h e e a r l y 1930's. S u c c e s s f u l o p e r a t i o n s i n c l u d e wood frame t r a n s p o r t a b l e u n i t s f o r RCAF p r o j e c t s i n remote bases and a few o t h e r v e n t u r e s i n i s o -l a t e d n o r t h e r n a r e a s ( P l a t t s , 1964b). The Nuway Company i n London, O n t a r i o i s r e p o r t e d t o have s u c c e s s f u l p r o d u c e d s e c t i o n a l houses on a s m a l l - s c a l e b a s i s s i n c e 1947 i n c o n v e n t i o n a l h o u s i n g m a r k e t s . A number of o t h e r companies h a v e ^ e i t h e r a t t e m p t e d t o pr o d u c e c o m p l e t e l y manufac-v t u r e d houses and f a i l e d , o r have i n v e s t i g a t e d t h e p o s s i b i l i t y and de-c i d e d a g a i n s t i t . Among t h o s e t h a t have n o t suc c e e d e d a r e L u s t r o n C o r p o r a t i o n and F a i r c h i l d A i r c r a f t . I n t h e U.S.A., G e n e r a l M o t o r s has i n v e s t i g a t e d f a c t o r y - b u i l t h o u s i n g on an a s s e m b l y - l i n e b a s i s s e v e r a l t i m e s s i n c e 1930 and d e c i d e d a g a i n s t e n t r y , and C h r y s l e r C o r p o r a t i o n was a l s o r e c e n t l y r e p o r t e d t o be i n v e s t i g a t i n g t h e p o t e n t i a l ( F i n a n c i a l P o s t , 1970a). " The same s o u r c e a l s o i n d i c a t e d t h a t a number o f major U.S. c o r p o r a t i o n s a r e e i t h e r o p e r -a t i n g , b u i l d i n g , o r p l a n n i n g t o b u i l d p l a n t s t o produce s e c t i o n a l h o u s i n g , i n c l u d i n g : B o i s e Cascade, O c c i d e n t a l P e t r o l e u m , Penn C e n t r a l , U.S. ?ly$-wood-Champion P a p e r s , A m e r i c a n S t a n d a r d , and I n t e r n a t i o n a l T e l e p h o n e and T e l e g r a p h . The most s i g n i f i c a n t development a l o n g t h e s e l i n e s I n Canada i s the house f a c t o r y o p e r a t e d by A l c a n D e s i g n Homes (a s u b s i d i a r y o f A l c a n ) a t Woodstock, O n t a r i o . O p e r a t i n g s i n c e mid-1968, t h e p l a n t has an u l t i -mate c a p a c i t y of 2,400 houses p e r y e a r . ( H o l r o y d , 1969).. I t i s . r e p o r t e d t h a t t h e p l a n t i s a b l e t o produce, two s t o r e y , s e m i - d e t a c h e d , and town-houses .as w e l l as s i n g l e — f a m i l y d w e l l i n g s . Completed u n i t s a r e t r a n s -p o r t e d up t o 150 m i l e s f o r e r e c t i o n . . These h o u s e s , w h i c h meet N a t i o n a l B u i l d i n g Code r e g u l a t i o n s and q u a l i f y for.NHA f i n a n c i n g , a r e p r i c e d as low as $14,900 i n c l u d i n g f u r n i t u r e , a f u l l basement,, l o t and s i t e c o s t s ( H o l r o y d , 1 9 6 9 ) . The s i g n i f i c a n c e o f . t h i s o p e r a t i o n i s t h a t t h e houses a r e of wood frame c o n s t r u c t i o n (as have been a l l c o m m e r c i a l a t t e m p t s a t s e c t i o n a l h o u s i n g i n t h i s c o u n t r y ) . A l t h o u g h i t i s t o o e a r l y t o d e t e r -mine t h e s u c c e s s of t h i s v e n t u r e , i t i s . c l a i m e d . t h a t t h e t e c h n i c a l p r o d u c -t i o n problems have been s o l v e d . ( F i n a n c i a l P o s t , 1970a), w h i c h . a p p e a r s t o s u p p o r t t h e p o s i t i o n .that wood frame c o n s t r u c t i o n , can be s u c c e s s f u l l y em-p l o y e d i n c o m p l e t e . f a c t o r y - b u i l t c o n v e n t i o n a l l y - d e s i g n e d h o u s e s . Whether, c o s t s a r e s i g n i f i c a n t l y r e d u c e d b e l o w t h o s e t h a t would.be i n c u r r e d , u s i n g a f a c t o r y - b u i l t component package and s i t e a s s e m b l y i s d e b a t a b l e . However,, t h e s e c t i o n a l house does p r o v i d e a much f a s t e r b u i l d i n g t i m e and hence a f a s t e r r e c o v e r y of funds sunk i n t h e d w e l l i n g u n i t . As n o t e d , t h i s , i s an i m p o r t a n t c o n s i d e r a t i o n f o r most b u i l d e r s . A c c o r d i n g t o P l a t t s (1968c) , I s r a e l has u s e d t h e c o n c r e t e box a p p r oach t o some.extent and the USSR s t i l l does. I n E u r o p e , c o n c r e t e boxes have been, e m p l o y e d . f o r . t h e h i g h - r s e r v i c e ..core a r e a s s u c h as bathrooms and k i t c h e n s . The w e i g h t o f t h e s e u n i t s ( e i g h t t o n s .or more.) ha s l e d . t o a t t e m p t s t o d e v e l o p wood.frame.core u n i t s on a c o n c r e t e f l o o r s l a b . I n b o t h Canada and t h e U.S.A., co m p l e t e and p a r t i a l bathroom c o r e u n i t s of g l a s s , f i b r e r e i n f o r c e d p l a s t i c s have v e r y r e c e n t l y become a v a i l a b l e . H i l l , . . A . W. (1966) d e s c r i b e d two c o n c r e t e , box.systems d e v e l o p e d i n G r e a t B r i t a i n w h i c h a r e s u i t a b l e f o r b o t h .low- and h i g h - r i s e a p a r t m e n t s : t h e WILMAC s y s t e m , w h i c h u s e s seven boxes per. h o u s i n g u n i t , and t h e TRUSCON sy s t e m , w h i c h employs 10 s e c t i o n s , p e r d w e l l i n g u n i t . . The c o m p e t i t i v e p o s i -t i o n of t h e s e systems was n o t d i s c u s s e d . A 500-room, 2 1 - s t o r e y h o t e l was c o n s t r u c t e d i n Texas two y e a r s ago of c o m p l e t e d c o n c r e t e b o x e s , .the f i r s t m ajor . v e n t u r e of. t h i s t y p e i n : NdiVth" America. ( A r c h i t e c t u r a l .Record,. 1 9 6 8 ) . More r e c e n t l y , t h e Jones and. L a u g h l i n S t e e l C o r p o r a t i o n of P i t t s -b u r g h and. Donn P r o d u c t s . o f C l e v e l a n d formed a.new company, J a l - D o n n Modu-l a r B u i l d i n g s , I n c o r p o r a t e d , t o p r o d u c e s t e e l . a p a r t m e n t housei<modules w h i c h can be s t a c k e d t h r e e s t o r e y s h i g h without., a d d i t i o n a l s u p p o r t . ( E n g i -n e e r i n g News—Record, 1969). Each d w e l l i n g u n i t i s composed o f two s e c -t i o n s , t h e t o t a l c o s t of w h i c h i s . about $14,000 t o $17,000. . S l a y t e r (1966) d e s c r i b e d t h e development program of a s t e e l frame s e c t i o n a l h o u s e . i n . t h e U.S.A. w h i c h began i n 1962. W i t h t h e c o - o p e r a t i o n o f U.S. S t e e l , . 10. r e s i -d e n t i a l b u i l d i n g s were c o n s t r u c t e d i n a p i l o t - p l a n t o p e r a t i o n . . I t was c o n c l u d e d t h a t t h i s s y s t e m , u s i n g a s t e e l . s p a c e - f r a m e as t h e s t r u c t u r a l b a s e , was b o t h t e c h n i c a l l y f e a s i b l e and e c o n o m i c a l l y p r a c t i c a l . I n f l u e n c e of B u i l d i n g Codes B u i l d i n g codes , p r e v i o u s l y .discussed..with r e s p e c t t o . i n n o v a t i o n s , have a l s o p r o v i d e d . a n impediment t o advanced i n d u s t r i a l i z a t i o n . A c c o r d i n g t o P l a t t s ( 1 9 6 4 b ) , l o c a l b u i l d i n g codes do.not s e r i o u s l y h i n d e r o r r a i s e t h e c o s t s of s i t e - b u i l t houses o r t h e t y p i c a l p a r t i a l l y p r e f a b r i c a t e d house. However, t h e y do r e s t r i c t a d d i t i o n a l shop c o n t e n t i n many a r e a s and a r e a major block, t o systems t h a t i n c l u d e i n n o v a t i o n s i n . s t r u c t u r e o r m a t e r i a l s , e s p e c i a l l y where a l a r g e market a r e a i s r e q u i r e d t o a c h i e v e economic v o l -umes. Here, t h e l a c k o f u n i f o r m i t y , between codes p r e v e n t s l a r g e s c a l e f a c t o r y p r o d u c t i o n o f a u n i f o r m p r o d u c t . The r e s u l t has been t h a t house packages have been k e p t i n c o m p l e t e and have been s o l d p r i m a r i l y i n r u r a l a r e a s . I n c r e a s i n g p r e s s u r e s from a l l segments.of t h e b u i l d i n g i n d u s t r y f o r t h e a d o p t i o n o f a u n i f o r m b u i l d i n g code a c r o s s Canada w i l l p r o b a b l y l e a d at. l e a s t t o r e g i o n a l u n i f o r m i t y i n t h e n e a r f u t u r e . Such a d e v e l o p -ment w i l l u n d o u b t e d l y promote a w i d e r a d o p t i o n of f a c t o r y - b u i l t . h o u s i n g of a l l t y p e s . I n c l u d e d i n t h e q u e s t i o n of .codes i s t h e m a t t e r of f a c t o r y v e r s u s o n - s i t e i n s p e c t i o n of houses by l o c a l b u i l d i n g i n s p e c t o r s . F a c -t o r y i n s p e c t i o n w i l l p r o b a b l y be a c h i e v e d more e a s i l y t h a n u n i f o r m i t y , as e x e m p l i f i e d by t h e s u c c e s s of A l c a n D e s i g n Homes i n o b t a i n i n g i t t h r o u g h s p e c i a l arrangements i n a r e a s where the. N a t i o n a l B u i l d i n g Code, i s a d m i n i s -t e r e d . M o r e o ver, i t i s t h e p o l i c y of t h e A s s o c i a t e Committee on t h e N a t i o n -a l B u i l d i n g Code t h a t t h i s code s h o u l d be w r i t t e n t o a p p l y e q u a l l y t o f a c -t o r y and c o n v e n t i o n a l b u i l d i n g (Webb and L e g g e t , 1967). I t i s a l s o n o t a b l e t h a t a committee was formed o v e r a y e a r ago under t h e c o - o r d i n a t i o n of. t h e C a n a d i a n S t a n d a r d s A s s o c i a t i o n w i t h t h e p u r p o s e of c r e a t i n g n a t i o n a l s t a n -d a r d s f o r t h e i n s p e c t i o n of houses on t h e f a c t o r y assembly, l i n e r a t h e r t h a n on s i t e ( M a t h i a s , 1 9 6 9 ) . I t would t h u s appear t h a t t h e way i s b e i n g paved b o t h f o r i n n o v a t i o n s and more s o p h i s t i c a t e d , l a r g e s c a l e systems o f b u i l d -i n g . European B u i l d i n g Systems Much i n t e r e s t has been g e n e r a t e d i n t h e p a s t few y e a r s i n the-many b u i l d i n g systems w h i c h have been d e v e l o p e d i n Europe. As e a r l y as 1965, c l a i m s have been made o f 250. t o 400 d i f f e r e n t b u i l d i n g . s y s t e m s i n Europe ( E n g i n e e r i n g , 1 9 6 5 ) . B u i l d i n g systems i n a v a r i e t y o f forms have now,been w i d e l y adopted on t h a t c o n t i n e n t ( f a c t o r y , systems p r o d u c e up t o 70 p e r c e n t o f a l l h o u s i n g i n some S c a n d i n a v i a n c e n t r e s ) , and have pene-t r a t e d .the U.S.A. t o a l e s s e r e x t e n t . , One p r o m i n e n t f e a t u r e o f t h e s e systems i s t h a t many of t h e s u c c e s s f u l ones a r e based on p r e c a s t c o n c r e t e l o a d b e a r i n g p a n e l s ( H i l l , A. W., 1966). Most o f these, c o n c r e t e b u i l d i n g systems h a v e f b e e n f o r m u l t i -f a m i l y d w e l l i n g s , b u t H i l l r e p o r t e d t h a t t h e y have a l s o been used s u c c e s s -f u l l y i n two and t h r e e s t o r e y h o u s e s . P l a t t s has a t t r i b u t e d t h e s u c c e s s o f l a r g e - p a n e l c o n c r e t e systems t o t h e i r i n h e r e n t s i m p l i c i t y ; a. s i n g l e l o w -c o s t m a t e r i a l p r o v i d e s s e v e r a l f u n c t i o n s : , s t r u c t u r a l s u p p o r t , f i r e and sound r e s i s t a n c e , and f i n i s h i n c o r p o r a t e d i n a few l a r g e p a r t s w h i c h can be q u i c k l y a ssembled. The movement toward i n d u s t r i a l i z e d b u i l d i n g i n Europe was due l a r g e l y t o a h i g h h o u s i n g demand, p a r t i c u l a r l y f o r m u l t i - f a m i l y s t r u c t u r e s i n d e n s e l y p o p u l a t e d a r e a s . (Concentrated.demand i s one of t h e e s s e n t i a l r e q u i r e m e n t s f o r t h e s u c c e s s of h i g h volume b u i l d i n g s y s t e m s , p a r t i c u l a r l y where heavy component systems and a h i g h c a p i t a l i n v e s t m e n t a r e r e q u i r e d . ) European v e n t u r e s have a l s o been w i d e l y f o s t e r e d by p o l i t i c a l - e c o n o m i c , a t t i t u d e s . w h i c h e n c o u r a g e e f f e c t i v e p r e - p l a n n i n g , , n a t i o n a l p e r f o r m a n c e codes, s t a n d a r d i z a t i o n , market c o n t i n u i t y and the r a t i o n a l u s e of l a n d ( P l a t t s , 1968b). . C a n a d i a n i n t e r e s t i n . European i n d u s t r i a l i z e d b u i l d i n g . , , and t h e u p s u r g e .in m u l t i - f a m i l y . d w e l l i n g s . I n Canada, r e s u l t e d .in.a t h o r o u g h i n v e s t i g a t i o n of a number of b u i l d i n g systems i n N o r t h e r n European coun-t r i e s where Canadian, b u i l d i n g c o n d i t i o n s are.most, n e a r l y a p p r o x i m a t e d . The s t u d y o f f i e l d and f a c t o r y o p e r a t i o n s . c a r r i e d out by t h e - D i v i s i o n of B u i l d i n g . R e s e a r c h , NRC, i n a 12-month p e r i o d d u r i n g 1966-67, r e v i e w e d s e v e r a l systems i n d e p t h p l u s s e v e r a l i n l e s s d e t a i l , w i t h t h e o b j e c t i v e o f a s s e s s i n g t h e p o t e n t i a l s and problems f r o m t h e C a n adian v i e w p o i n t ( P l a t t s , 1 9 6 8 c ) . The l a r g e s t b u i l d i n g c o n t r a c t o r s , i n Europe are.now h e a v i l y com-m i t t e d t o systems b u i l d i n g u s i n g c e n t r a l p l a n t s t o f o r m . t h e components w h i c h a r e t h e n s h i p p e d t o t h e s i t e f o r . e r e c t i o n , a p r o c e s s w h i c h i s , i n e f f e c t , an e x t e n s i o n o f the p l a n t assembly l i n e ( P l a t t s , 1 968a). L a r g e -p a n e l c o n c r e t e systems i n c l u d e , i n p r e c a s t f o r m , a l l c r o s s w a l l s and g a b l e s , f l o o r s , e l e v a t o r s h a f t s , s t a i r s , d u c t s and .sometimes u n i t b a t h -rooms and p a r t i a l k i t c h e n s , and even p r e c a s t f o u n d a t i o n s and basements. I n t e r i o r s and s e r v i c e s a r e now f r e q u e n t l y advanced.subsystems i n c l u d i n g . p r e c i s e l i g h t p a r t i t i o n s , doors., c a b i n e t r y , t r i m and...closet w a l l s , p r e f i n i s h e d i n v i n y l f i l m or baked enamels, and u n i t cores. ( P l a t t s , 1 9 6 8 a ) . . M o s t . o f t e n , t h e p r o d u c e r of t h e main s t r u c t u r a l s y s t e m p u r c h a s e s t h e i n t e r i o r . s y s t e m . d e s i r e d from a v a r i e t y , o f f e r e d on t h e open.market; s u c h i n t e r i o r , systems a r e s u i t a b l e f o r use w i t h i n , s t e e l frame, systems as w e l l . I t may a l s o be n o t e d t h a t . t h e t e c h n i c a l . s o u n d n e s s , o f S c a n d i n a v i a n systems, s u r p a s s e s m o s t ' C a n a d i a n a p a r t m e n t . c o n s t r u c t i o n . The s u c c e s s f u l t o t a l s y s t e m s ' b u i l d e r s a r e most o f t e n l a r g e heavy e n g i n e e r i n g c o n t r a c t o r s w i t h top l e v e l management, p l a n n i n g and t e c h n i c a l f o r c e s , and.adequate c a p i t a l ; s e l d o m .are m a t e r i a l s groups i n v o l v e d . Two o t h e r u n r e l a t e d f e a t u r e s a r e w o r t h n o t i n g . F i r s t , l o w - r i s e , h o u s i n g d e v e l o p -ments a r e becoming i n c r e a s i n g l y common i n S c a n d i n a v i a d e s p i t e i n c r e a s i n g u r b a n p r e s s u r e s ( P l a t t s , 1 9 6 8 c ) . Second, wood systems have been used s u c c e s s f u l l y t h r o u g h o u t i n t e r i o r s o f : m u l t i - f a m i l y h o u s i n g b l o c k s , and p r e f i n i s h e d p a n e l s o f wood frame o r o t h e r . l i g h t , c o n s t r u c t i o n . a r e - c o m m o n . i n e x t e r i o r w a l l s . C o n c r e t e B u i l d i n g Systems i n Canada The r e l e v a n c e of N o r t h e r n European.systems t o Canada depends on t h e i r , a d a p t a b i l i t y t o t h i s c o u n t r y . T h e i r i n t r o d u c t i o n t o Canada has a l -r e a d y begun, b u t t h e i r , s u c c e s s i s y e t t o be p r o v e n . The p r i m e t a r g e t of t h e s e systems i s a t p r e s e n t t h e apartment market i n t h e T o r o n t o a r e a . S h o u l d t h e y p r o v e s u c c e s s f u l t h e r e , e x p a n s i o n t o o t h e r h i g h d e n s i t y pop-u l a t i o n c e n t r e s can be a n t i c i p a t e d . A b r i e f o u t l i n e o f t h e i r n a t u r e and p r o g r e s s f o l l o w s . J e s p e r s e n - K a y Systems L i m i t e d (a.f;Canadian company) h o l d s e x c l u -s i v e r i g h t s t o t h e J e s p e r s e n . b u i l d i n g s y s t e m f o r Canada, t h e U.S.A., t h e Bahamas and t h e C a r i b b e a n c o u n t r i e s ( E s c o t t , 1969). T h i s s y s t e m , of. D a n i s h o r i g i n , has been s u c c e s s f u l l y u s e d i n England,. Sweden, Denmark and I s r a e l . The f i r s t f a c t o r y f o r t h e p r o d u c t i o n , o f p r e c a s t c o n c r e t e , p a n e l s u s i n g t h e J e s p e r s e n method was completed j u s t n o r t h e a s t o f Toronto, i n December, 1 9 6 9 ( F i n a n c i a l P o s t , 1970b) and, by agreement, a second p l a n t w i l l be b u i l t somewhere I n Canada i n . t h e n e a r f u t u r e . The s h i p p i n g r a d i u s . f r o m t h e . p l a n t i s about 50 m i l e s and the. company..is i n v e s t i g a t i n g p o r t a b l e p l a n t s . ( C a n a d i a n B u i l d e r , 1969d) . The c o m p u t e r - r e g u l a t e d p r o d u c t i o n equipment has a c a p a c i t y of about 2,500 l i v i n g u n i t s a n n u a l l y , I n c l u d i n g b o t h h i g h and low forms of m u l t i p l e h o u s i n g (Jlsco.tt, 1969). The f i r s t c o m m e r c i a l p r o j e c t t o . b e u n d e r t a k e n . i s a 1 8 4 - s u i t e apartment i n . T o r o n t o . M o d u l a r P r e c a s t C o n c r e t e S t r u c t u r e s L i m i t e d has a l s o c o n s t r u c t e d a f a c t o r y for. t h e p r o d u c t i o n of p r e c a s t c o n c r e t e p a n e l s i n . t h e T o r o n t o a r e a ( C a n a d i a n B u i l d e r , 1969d). The f a c t o r y has.an i n i t i a l c a p a c i t y of 1,000 u n i t s p e r y e a r and i s t o be d o u b l e d i n s i z e i n 1971. A c c o r d i n g t o Hanson. ( 1 9 6 9 ) , t h i s company i s j o i n t l y owned by f i v e o f Canada's major; development companies ( p r e s e n t l y r e s p o n s i b l e f o r a l a r g e p e r c e n t a g e of t h e h i g h e r - p r i c e d h o u s i n g developments i n T o r o n t o ) and Wates: L i m i t e d of London, E n g l a n d w h i c h has o v e r 25 y e a r s ' e x p e r i e n c e i n p r e c a s t c o n c r e t e system b u i l d i n g methods. He a l s o i n d i c a t e d t h a t t h e Wates System i s u s e d f o r b o t h l o w - and h i g h - r i s e forms of m u l t i p l e h o u s i n g . M o d u l a r P r e c a s t w i l l p roduce b o t h f o r open market o p e r a t i o n s and t h e c o n s o r t i u m w h i c h was formed as a s s u r a n c e of "a s t e a d y m a r k e t . B r a m a l e a C o n s o l i d a t e d Developments. L i m i t e d a l s o has p l a n s t o b u i l d a f a c t o r y f o r t h e p r o d u c t i o n o f p r e c a s t c o n c r e t e p a n e l s i n t h e T o r o n t o a r e a , s u b j e c t t o t h e s u c c e s s f u l a c c e p t a n c e of an 8 9 - u n l t a p a r t -ment b l o c k a t B r a m a l e a , O n t a r i o ( F i n a n c i a l P o s t , 1970b). The Swedish S k a r n e System i s t h e one u n d e r c o n s i d e r a t i o n . As a r e s u l t of c o n s t a n t e v o l u t i o n , t h e Skarne System now c o m p r i s e s f i v e d i f f e r e n t element methods ( S m i t h , H. -D., 1969). B o t h c e n t r a l and p o r t a b l e f a c t o r i e s a r e u s e d t o . p r o d u c e t h e c o n c r e t e p a n e l s . T h i s s y s t e m can a l s o p r o d u c e b o t h l o w - and h i g h - r i s e m u l t i p l e d w e l l i n g s . A f o u r t h s y s t e m , t h e No-Fines. C o n c r e t e System, has been promoted among members of t h e C a n a d i a n b u i l d i n g i n d u s t r y , b u t h a s . n o t y e t been em-p l o y e d i n o t h e r t h a n p i l o t p r o j e c t s ( G i d d e n s , 1969). U n l i k e . t h e above methods, .the N o - F i n e s System uses o n - s i t e p r o d u c t i o n o f t h e s t r u c t u r a l s h e l l w i t h , a h i g h d e g r e e . o f . p r e f a b r i c a t i o n of i n t e r n a l components. I t has been c l a i m e d t h a t t h i s method h a s . c o m p r i s e d about 50 p e r c e n t o f t h e e n t i r e i n d u s t r i a l i z e d h o u s i n g p r o g r a m s . i n . t h e U n i t e d Kingdom ( G i d d e n s , 1969). • I t i s a l s o s u i t a b l e f o r l o w - and h i g h - r i s e d e v e l o p m e n t s . As n o t e d , a n o t h e r e n t r y i n t o systems b u i l d i n g u s i n g p r e c a s t c o n -c r e t e i s P o l y m e r , a C a n a d i a n p e t r o c h e m i c a l company w h i c h has purchased., e x c l u s i v e C a n a d i a n r i g h t s t o t h e Uniment system o f S t r e s s e d . S t r u c t u r e s , a . l a r g e U.S. b u i l d e r ( F i n a n c i a l P o s t , 1 9 7 0 c ) . T h i s s y s t e m b o a s t s s t r o n g p r e s t r e s s e d ( s t a t e d as " c h e m i c a l l y " p r e s t r e s s e d ) c o n c r e t e p a n e l s w h i c h can be. as t h i n as two i n c h e s f o r w a l l s , c e i l i n g s o r f l o o r s , and i s s u i t -a b l e f o r a w i d e range of s i n g l e - and m u l t i - f a m i l y d w e l l i n g s . ' As f a r as the f o r e s t i n d u s t r i e s a r e c o n c e r n e d , t h e s i g n i f i c a n c e o f t h e s e c o n c r e t e p a n e l b u i l d i n g systems e n t e r i n g C a n a d a . l i e s , p r i m a r i l y in7 .the a r e a o f l o w - r i s e m u l t i p l e d w e l l i n g s . That i n d u s t r i a l i z e d b u i l d -i n g . i s h e r e t o s t a y i s an a c c e p t e d . f a c t . That the above c o n c r e t e systems a r e s u i t a b l e f o r e l o w - r i s e h o u s i n g has been p r o v e n o v e r many y e a r s i n . E u r o p e . W i t h c l a i m s o f c o s t s a v i n g s r a n g i n g f r o m s e v e n t o 15 p e r ce n t over conven-. t i o n a l methods, t h e y appear t o be q u i t e c o m p e t i t i v e . Perhaps t h e r e i s a q u e s t i o n of consumer a c c e p t a n c e o f s t a n d a r d i z e d , r e p e t i t i v e d w e l l i n g s . I n v i e w of t h e p r e s e n t monotonous appearance o f many, of our sub u r b s , . a n d t h e s i m i l a r i t y o f many b o x - l i k e a p a r t m e n t . b u i l d i n g s e r e c t e d by c o n v e n t i o n a l methods, any q u e s t i o n o f consumer, a c c e p t a n c e on t h e b a s i s . o f . appearance i s p r o b a b l y more academic t h a n r e a l . W i t h g r e a t e r a r c h i t e c t u r a l i n p u t and h i g h volume p r o d u c t i o n , t h e appearance o f s y s t e m s - b u i l t s t r u c t u r e s w i l l p r o b a b l y n o t h i n d e r t h e i r a c c e p t a n c e . C o n c r e t e and o t h e r , systems may o n l y . e n t e r Canada g r a d u a l l y , b u t t h e i r . a c c e p t a n c e c o u l d p r o v i d e s t r o n g c o m p e t i t i o n f o r wood frame systems i n l o w - r i s e m u l t i - f a m i l y d w e l l i n g s . W i t h .the p r e s e n t p r e d o m i n a t i n g p o s i t i o n o f wood frame c o n s t r u c t i o n . i n t h e s e u n i t s . , t h e l o s s o f some mar-k e t s t o c o n c r e t e systems may be a n t i c i p a t e d . However, t h i s would s t i l l a ppear t o l i e i n t h e d i s t a n t f u t u r e . T h e r e have been few;> i n s t a n c e s , where C o n c r e t e : systems have been used f o r t h e p r o d u c t i o n o f s i n g l e - f a m i l y d w e l l i n g s . One i s t h e C o n c r e t e House P r o j e c t d e v e l o p e d by t h e V i c t o r i a n H o u s i n g Commission i n . A u s t r a l i a ( H o w e l l , 1966). When t h i s p r o j e c t f i r s t began, t h e o u t p u t was p r i m a r i l y d e t a c h e d houses w h i c h were s u c c e s s f u l l y p r o d u c e d , b u t l a t e r p r o d u c t i o n swung.toward m u l t i - f a m i l y d w e l l i n g s . A c c o r d i n g t o Matthews ( 1 9 6 6 ) , c o n -c r e t e i s n e i t h e r t h e b e s t nor most e c o n o m i c a l s t r u c t u r a l m a t e r i a l i n s i n g l e and t w o - s t o r e y d w e l l i n g s . He contends t h a t t he advantage o f c o n -c r e t e a r e most p r o m i s i n g f o r m u l t i - s t o r e y c o n s t r u c t i o n where a p a r t m e n t s , s c h o o l s , and h o s p i t a l s p r e s e n t t h e b e s t o p p o r t u n i t i e s . f o r . i n d u s t r i a l i z a -t i o n . Even i n S c a n d i n a v i a n c o u n t r i e s , where p r e c a s t c o n c r e t e systems are. p r o l i f i c , v a r i o u s t y p e s o f wood f r a m e . p r e f a b r i c a t i o n systems a r e common f o r s i n g l e - f a m i l y h o u s e s . I t would t h u s appear t h a t wood frame c o n s t r u c t i o n i n / s i n g l e - f a m i l y houses w i l l n o t be t h r e a t e n e d by t h e advent o f c o n c r e t e p a n e l systems to,Canada. M e t a l , P l a s t i c , and. S t r u c t u r a l C l a y Systems I n d u s t r i a l i z e d . b u i l d i n g systems, u s i n g b a s i c m a t e r i a l s o t h e r t h a n c o n c r e t e (and wood) have a l s o been d e v e l o p e d i n Europe as w e l l as e l s e -where, b u t have y e t t o a c h i e v e w i d e s p r e a d u s e . S t r u c t u r a l s t e e l has n o t been as s u c c e s s f u l i n s y s t e m s ' b u i l d i n g as many of i t s a d v o c a t e s t h i n k , i t should, have been. T h i s i s l a r g e l y b e c a u s e i t i s p u r e l y a s t r u c t u r a l m a t e r i a l u n a b l e t o p e r f o r m o t h e r n e c e s s a r y f u n c t i o n s , and i s . s t i l l c o n -f r o n t e d w i t h problems o f . c o r r o s i o n and f i r e (McMeekin, 1 966). Systems w h i c h have been d e v e l o p e d t o d a t e u s e s t e e l as a s t r u c t u r a l framework on t o w h i c h l i g h t w e i g h t p a n e l s of wood, p l a s t i c , o r l i g h t w e i g h t , c o n c r e t e a r e hung. Such systems s t i l l r e t a i n c o n s i d e r a b l e c o m p l e x i t y and r e q u i r e o n - s i t e c o n s t r u c t i o n o f f i r e - p r o t e c t i v e and, a e s t h e t i c c o v e r i n g s . One s u c h s y s t e m , known as t h e . " T r u s t e e l System," has r e p o r t e d l y been u s e d i n t h e .U.K. i n t h e c o n s t r u c t i o n o f one and t w o - s t o r e y houses on a co n -t i n u a l b a s i s s i n c e 1945, and has p r o v e n c o m p e t i t i v e w i t h , t r a d i t i o n a l , b u i l d i n g - m e t h o d s ( H i l l , A. W., 1966). A c c o r d i n g t o t h e same a u t h o r , a second l i g h t w e i g h t r i g i d s t e e l frame system has a l s o been used t h e r e t o some e x t e n t . I t may be n o t e d t h a t t h e s e were d e v e l o p e d i n t h e absence o f wood frame h o u s i n g i n t h e U.K., where t h e l a t t e r has r e c e n t l y been, s u c c e s s f u l l y i n t r o d u c e d . Whether t h e s e s t e e l systems would be competl^-t i v e i n Canada, and whether t h e y w o u l d meet b u i l d i n g code r e q u i r e m e n t s , i s p e r h a p s q u e s t i o n a b l e , s i n c e no c o m m e r c i a l s t e e l systems f o r . h o u s e s have y e t e n t e r e d t h i s c o u n t r y . A l t h o u g h p l a s t i c s have been employed t o some e x t e n t i n European s y s t e m s , t h e y have n o r m a l l y been r e s t r i c t e d t o c l a d d i n g s and p a r t i t i o n s . F o r example, P l a t t s (1968b) has r e p o r t e d t h e u s e . o f l o a d b e a r i n g e x t e r i o r w a l l a s s e m b l i e s c o n s i s t i n g o f a moulded f i b r e g l a s s p l a s t i c e x t e r i o r on l i g h t w e i g h t c o n c r e t e i n a 2 1 - s t o r e y apartment b l o c k . i n E n g l a n d . .McMeekin . (1966) .has e x p r e s s e d o p t i m i s m . o v e r . t h e use of p l a s t i c s f o r c l a d d i n g s and p a r t i t i o n s b u t . i s d o u b t f u l of t h e i r u s e i n l o a d b e a r i n g c a p a c i t i e s , i n t h e n e a r f u t u r e . N e v e r t h e l e s s , i t has a l r e a d y been n o t e d t h a t bathroom c o r e u n i t s u s i n g , g l a s s f i b r e r e i n f o r c e d . p l a s t i c s a r e now c o m m e r c i a l l y a v a i l a b l e i n N o r t h . A m e r i c a . Systems o f i n d u s t r i a l i z e d b u i l d i n g , methods u s i n g . s t r u c t u r a l c e r -amics ( b r i c k and t i l e ) have been s l o w t o . d e v e l o p . Bradshaw (1966) has r e p o r t e d t h e development of o v e r 10 s u c h systems u s i n g a v a r i e t y o f b a s i c c l a y u n i t s , i n c l u d i n g s o l i d a n d . p e r f o r a t e d b r i c k s , and h o l l o w b l o c k s . These developments'may be d i v i d e d i n t o two groups t o i n c l u d e n o n - l o a d b e a r i n g b r i c k v e n e e r pan e l s , , and systems i n v o l v i n g c l a y u n i t s f a c e d w i t h m o r t a r , m o s a i c , or c a s t w i t h i n in situ c o n c r e t e . I n t h e f i r s t c a t e g o r y , a Swedish s y s t e m f o r h o u s i n g o f u p . t o t h r e e s t o r e y s has been d e v e l o p e d u s i n g s a n d w i c h p a n e l c o n s t r u c t i o n com-r-pose d . o f e x t e r n a l f a c i n g b r i c k s e p a r a t e d from an i n n e r p a r t i t i o n b l o c k by 4 - i n c h r o c k , w o o l i n s u l a t i o n . P r e f a b r i c a t e d b r i c k p a n e l s have a l s o been d e v e l o p e d i n H o l l a n d , Germany, S w i t z e r l a n d , U.S.A., Denmark and G r e a t B r i t a i n (Bradshaw, 1966). The second group i n c l u d e s l o a d b e a r i n g w a l l s and f l o o r s . Sev-e r a l s y s t e m s , p r i m a r i l y f r o m F r a n c e , were d e s c r i b e d by Bradshaw, a l l of w h i c h a r e more complex th a n p r e c a s t c o n c r e t e p a n e l s and o f t e n i n c l u d e a c o n c r e t e s u r r o u n d t o h o l d t h e . c l a y b l o c k s i n p l a c e . I t .has been r e -p o r t e d r e c e n t l y t h a t a p i l o t p l a n t . i n Canada i s now p r o d u c i n g b r i c k , p a n e l s (Globe.and M a i l , 1970b). ' The c o m m e r c i a l development of s u c h p a n e l s w i l l p r o b a b l y h e l p masonry m a i n t a i n i t s p r e s e n t p o s i t i o n i n .Canadian h o u s i n g , but s u f f i c i e n t i n d u s t r i a l i z a t i o n t o r e s u l t , i n r e p l a c e m e n t of wood frame c o n s t r u c t i o n i s h i g h l y u n l i k e l y . The R o l e s o f Competing M a t e r i a l s I t i s a p p a r e n t from t h e b r i e f , d e s c r i p t i o n s o f b u i l d i n g systems above t h a t a w i d e v a r i e t y has been d e v e l o p e d u s i n g . a numberaof b a s i c m a t e r i a l s . I t i s i n t e r e s t i n g t o n o t e t h e t y p e s o f b a s i c m a t e r i a l s used i n p r o j e c t s a c c e p t e d i n t h e " O p e r a t i o n s B r e a k t h r o u g h " h o u s i n g . p r o g r a m i n the U.S.A. Timmins (1970) has i n d i c a t e d t h a t t h e y a r e as f o l l o w s : C o n c r e t e 49 p e r c e n t Wood 26 p e r c e n t M e t a l s 15 p e r c e n t P l a s t i c s 10 p e r c e n t A l t h o u g h t h e s e f i g u r e s i n c l u d e a l l . f o r m s o f d w e l l i n g s , t he h i g h p r o p o r t i o n o f m e t a l s and p l a s t i c s systems r e p r e s e n t s i g n i f i c a n t developments i n t h e us e .of t h e s e m a t e r i a l s w h i c h have up t o now been u s e d s p a r i n g l y i n r e s i -d e n t i a l c o n s t r u c t i o n . S i l b e r ( 1 9 6 6 ) , i n f o r e c a s t i n g t h e use o f m a t e r i a l s i n B r i t i s h : , h o u s i n g , p r e d i c t e d t h a t wood frame c o n s t r u c t i o n would predominate..in l o w -r i s e h o u s i n g , b r i c k w o r k f o r apar t m e n t s o f f o u r t o 10 s t o r e y s , and. c o n c r e t e and s t e e l f o r t a l l e r b u i l d i n g s . I t i s i n t e r e s t i n g t h a t masonry c o n s t r u c -t i o n has been t r a d i t i o n a l l y u s e d i n l o w - r i s e h o u s i n g i n . E n g l a n d , b u t t h a t t h e r e c e n t i n t r o d u c t i o n o f Ca n a d i a n wood.frame h o u s e — b u i l d i n g t e c h n i q u e s t o t h a t c o u n t r y has been q u i t e s u c c e s s f u l . The i m p l i c a t i o n s o f t h e a b o v e . o b s e r v a t i o n s , o f p r e s e n t . a n d p o t e h - . t i a l developments i n i n d u s t r i a l i z e d . b u i l d i n g . i s t h a t w i t h i n t h e . f o r e s e e a b l e f u t u r e , wood, frame s t r u c t u r e s . w i l l . c o n t i n u e t o dominate, f o r s i n g l e - f a m i l y . and l o w - r i s e m u l t i - f a m i l y d w e l l i n g s . C o n c r e t e systems w i l l p r e d o m i n a t e i n m u l t i - f a m i l y s t r u c t u r e s over t h r e e , s t o r e y s . Masonry c o n s t r u c t i o n w i l l p r o b a b l y - r e t a i n a m i n o r r o l e i n . s i n g l e - f a m i l y , and l o w - and medium-height m u l t i - f a m i l y , d w e l l i n g s . M e t a l b u i l d i n g ? s y s t e m s w i l i . p r o b a b l y e n t e r b o t h l o w - and h i g h - r i s e h o u s i n g markets t o . a l i m i t e d e x t e n t , depending, on t h e i r . . a b i l i t y . t o r e d u c e c o s t s r e l a t i v e t o o t h e r m a t e r i a l s g r o u p s . Over t h e l o n g e r t e r m i t may be a n t i c i p a t e d t h a t wood frame systems w i l l meet t h e i r . s t r o n g e s t c o m p e t i t i o n from p r e c a s t c o n c r e t e systems i n l o w -r i s e m u l t i - f a m i l y d w e l l i n g s . CONCLUSIONS: IMPLICATIONS FOR THE FOREST INDUSTRIES A number o f i m p l i c a t i o n s can be drawn from developments i n r e s i d e n t i a l c o n s t r u c t i o n . A l t h o u g h . a s c a r c i t y o f d a t a p r e c l u d e s . m a k i n g an a c c u r a t e q u a n t i t a t i v e a p p r a i s a l , o f p a s t and p o s s i b l e , f u t u r e , r e p l a c e -ment o f wood by s u b s t i t u t e m a t e r i a l s i n h o u s i n g , some i n t e r e s t i n g , o b s e r -v a t i o n s can be made on t h i s whole q u e s t i o n . ' Trends i n d w e l l i n g t y p e s , p a r t i c u l a r l y towards apartment c o n s t r u c -t i o n and away f r o m s i n g l e - f a m i l y houses a r e a major cause o f t h e l o s s o f m a r k e t s . f o r wood p r o d u c t s i n r e s i d e n t i a l c o n s t r u c t i o n . U s i n g a v a i l a b l e d a t a , i t i s o n l y p o s s i b l e t o make a r o u g h . e s t i m a t e o f t h e i m p a c t . t h e s e t r e n d s have had on wood consumption i n Canada. Such anmestimate has been made u s i n g t h e d a t a on d w e l l i n g u n i t c o m p l e t i o n s from T a b l e 5 and t h e wood con s u m p t i o n d a t a f r o m T a b l e 10. Consumption d a t a f o r 1962 f o r two s e p a r a t e c a t e g o r i e s o f d w e l l -i n g u n i t s a r e shown i n T a b l e 10: (a) one and two f a m i l y u n i t s ; and (b) m u l t i - f a m i l y u n i t s . The d i f f e r e n c e between t h e s e two f i g u r e s r e p r e s e n t s t h e d e c r e a s e i n wood consumption w h i c h o c c u r s when a d w e l l i n g u n i t i s r e a l i z e d as a m u l t i - f a m i l y u n i t r a t h e r t h a n a one o r t w o - f a m i l y u n i t ( i . e . , a d e c r e a s e i n con s u m p t i o n o f 6,690 bd. f t . o f lumber, 1,210 sq.-f t . o f plywood and v e n e e r , and 970.sq. f t . o f b u i l d i n g b o a r d ) . A p p l y -i n g t h e s e f i g u r e s t o t h e d w e l l i n g u n i t c o m p l e t i o n s d a t a i n T a b l e 5, t h e l o s s i n consumption o f wood p r o d u c t s between I960.and 1969. due t o t h e t r e n d t o w a r d s apartment c o n s t r u c t i o n , has.been d e t e r m i n e d . The accumu-l a t e d l o s s o f wood m a r k e t s over t h i s p e r i o d has been e s t i m a t e d a t 1,355 m i l l i o n bd. f t . o f l u m ber, 245,075,;00.0--s.q./-- f t . o f plywood and.veneer, and 151,068,000 s q . f t . o f b u i l d i n g board.. I f one were t o use a b ase y e a r p r i o r t o 1960, t h e l o s s e s e s t i m a t e d would be even g r e a t e r . U s i n g t h e same consumption d a t a and an e s t i m a t e of new r e s i d e n -t i a l . c o n s t r u c t i o n t o 1974, a p r e d i c t i o n of t h e l o s s of wood m a r k e t s due t o t h e t r e n d toward a p a r t m e n t s i n Canada can be made f o r t h e p e r i o d 1969-74. Under ' P r o j e c t i o n s of H o u s i n g Demand', i t was i n d i c a t e d t h a t t h e f e d e r a l government i s committed t o one m i l l i o n new d w e l l i n g u n i t s , f o r t h e f i v e - y e a r , p e r i o d t o 1974, o r 200,000 u n i t s p e r y e a r . U s i n g t h i s f i g u r e , and a p r o j e c t e d i n c r e a s e i n t h e r e l a t i v e r a t e o f c o n s t r u c t i o n of m u l t i -f a m i l y u n i t s ( from 54 p e r c e n t . o f t o t a l c o m p l e t i o n s i n 1970 t o 62 p e r c e nt i n 1 9 7 4 ) , an e s t i m a t e o f t h e e f f e c t s of t h e s e t r e n d s on wood consump-t i o n has been made. S t i l l c o n s i d e r i n g 1960 as t h e b ase y e a r , t h e l o s s o f m a r k e t s f o r wood p r o d u c t s o v e r t h e 1969-74 p e r i o d due t o h o u s i n g t r e n d s i s e s t i m a t e d as f o l l o w s : 1,947 m i l l i o n bd. f t . of l u m ber, 352,110,000 s q . f t . of p l y -wood and v e n e e r , and 282,270,000 s q . f t . of b u i l d i n g b o a r d . S i m i l a r l o s s e s can be e x p e c t e d t o . c o n t i n u e t o about 1980 when the t r e n d t o apartment c o n s t r u c t i o n w i l l p r o b a b l y l e v e l o f f . There i s some i n d i c a t i o n t h a t t h e l o s s of. wood m a r k e t s due t o t h e s e t r e n d s may n o t be as g r e a t as would.be a n t i c i p a t e d .from u s i n g . p a s t d a t a . f o r f u t u r e p r e d i c t i o n s . There, i s g r o w i n g e v i d e n c e t h a t i n E u r o p e , t h e U.S.A., and more r e c e n t l y i n Canada, l o w - r i s e m u l t i p l e d w e l l i n g s a r e becoming, p o p u l a r , I f t h e s e d w e l l i n g s make up an . i n c r e a s i n g s h a r e of t o t a l m u l t i p l e , d w e l l i n g s i n t h e f u t u r e ( a s appears p r o b a b l e ) , t h e i m p a ct on wood consumption w i l l n o t be as g r e a t as c o u l d be e x p e c t e d s h o u l d h i g h - r i s e c o n s t r u c t i o n m a i n -t a i n or. i n c r e a s e i t s . - r e l a t i v e i m p o r t a n c e . A l t h o u g h i t has been s t a t e d t h a t t r e n d s i n t y p e s o f d w e l l i n g s c o n s t r u c t e d a r e b a s i c a l l y autonomously determined., t h e r e a r e two p o s s i b l e ways i n w h i c h t h e f o r e s t i n d u s t r i e s can i n f l u e n c e t h e s e t r e n d s . The f i r s t i s t o e n t e r t h e r e s i d e n t i a l c o n s t r u c t i o n f i e l d t h r o u g h v e r t i c a l i n t e g r a -t i o n , a s . a l a r g e number of f o r e s t p r o d u c t companies have done r e c e n t l y i n the.U.S.A. A l t h o u g h t h i s would e n s u r e t h e c o n s t r u c t i o n of d w e l l i n g s w h i c h consume l a r g e . v o l u m e s of wood p r o d u c t s , i t i s d o u b t f u l t h a t t h e f o r e s t : i n -d u s t r i e s c o u l d . c o n t r o l a s u f f i c i e n t l y l a r g e . p o r t i o n of t h e r e s i d e n t i a l con-s t r u c t i o n i n d u s t r y t o s i g n i f i c a n t l y a l t e r the. t r e n d i n d w e l l i n g t y p e s . The second, w a y . i n w h i c h t h e f o r e s t i n d u s t r i e s c o u l d i n f l u e n c e t h e t r e n d i n d w e l l i n g t y p e s i s t h r o u g h a program o f a c t i v e p r o m o t i o n of wood-b a s e d b u i l d i n g s y s t e m s . T h i s c o u l d i n v o l v e c l o s e c o - o p e r a t i o n between th e w o o d . i n d u s t r i e s and b u i l d e r s i n an e f f o r t t o improve t h e q u a l i t y of wood f r a m e . s t r u c t u r e s , and r e d u c e t h e c o s t . o f wood-based h o u s i n g s y s t e m s . By h e l p i n g t h e b u i l d e r r e d u c e h i s c o s t s , t h e f o r e s t i n d u s t r i e s w i l l be a b l e t o e n s u r e m a r k e t s f o r t h e i r p r o d u c t s . T h i s c o u l d c o n c e i v a b l y i n ^ v o l v e t h e p r o d u c t i o n of b e t t e r m a n u f a c t u r e d p r o d u c t s by t h e w o o d s . i n d u s -t r i e s , and p e r h a p s g r e a t e r p a r t i c i p a t i o n i n c u t - t o - s i z e - o p e r a t i o n s . W i t h t h e g r o w i n g emphasis on i n d u s t r i a l i z e d b u i l d i n g , t h e f o r e s t i n d u s t r i e s s h o u l d r e s e a r c h t h e needs of f a c t o r y - b u i l t h o u s i n g w i t h r e s p e c t t o m a t e r -i a l s r e q u i r e m e n t s , and be p r e p a r e d t o a l t e r t h e i r m a n u f a c t u r i n g f a c i l i t i e s t o accommodate t h e changes e v o l v i n g i n . b u i l d i n g methods. D i r e c t r e p l a c e m e n t of wood by s u b s t i t u t e m a t e r i a l s has a l s o , had a s i g n i f i c a n t i m p a c t on t h e c o n s u m p t i o n o f wood by t h e r e s i d e n t i a l c o n s t r u e -t i o n industry. However, a quantitative estimate of the extent of such replacement i s v i r t u a l l y impossible due to the lack, of appropriate data. .On the basis of the foregoing discussion on s u b s t i t u t i o n , there i s evidence that the s u b s t i t u t i o n of woodby other, materials w i l l , continue at.a rate equal to. that i n the past or at an even higher rate. Such f a c -tors as the increasing p r i c e of wood products r e l a t i v e to competing mater-i a l s , higher.R&.D expenditures i n .competing i n d u s t r i e s , and the movement toward performance c r i t e r i a i n b u i l d i n g codes, point to the development and acceptance of substitutes f o r wood i n construction. In order to combat the increasing competition from s u b s t i t u t e materials, the fo r e s t products i n d u s t r i e s w i l l have to increase t h e i r R & D e f f o r t i n three d i r e c t i o n s . First., i t i s necessary to continuously develop new production techniques and equipment i n order to increase p r o d u c t i v i t y and reduce manufacturing costs, with the aim of keeping wood products prices competitive. Second, there must be a greater e f f o r t at developing new products and improving the properties of. the basic wood'material. 1 For example, i f s a t i s f a c t o r y solutions could be found f o r two problem areas of wood, i t s combustibility and dimensional i n s t a b i l i t y , the markets f o r wood' products would.be v a s t l y expanded. The t h i r d area of research, market r e -search, i s one which i s becoming essential, due.to the increasing competitive-ness of•the construction market. The organization o f . f o r e s t products research.in Canada is.worthy of comment.. The f e d e r a l government, and industry have'.been primary'respon-s i b l e f o r . advances In wood products technology. in.the past,, yet a major, b e n e f i c i a r y has been the forest owners, i . e . , the p r o v i n c i a l p u b l i c s . The s i g n i f i c a n c e o f t h e f o r e s t r y s e c t o r t o s u c h p r o v i n c e s . a s . Quebec, O n t a r i o , and p a r t i c u l a r l y B r i t i s h Columbia,, w a r r a n t s much g r e a t e r p a r t i c i p a t i o n . b y them i n f o r e s t p r o d u c t s r e s e a r c h . - T h i s , c o u l d be r e a l i z e d , t h r o u g h g r e a t e r s u p p o r t o f u n i v e r s i t y r e s e a r c h programs, a n d . t h r o u g h . c o - o p e r a t i v e f e d e r a l -p r o v i n c i a l , programs . I n a d d i t i o n y -a.more c o - o r d i n a t e d e f f o r t i n wood-pro-d u c t s r e s e a r c h i s needed t o c o n s o l i d a t e and p l a n r e s e a r c h a c t i v i t i e s a t t h e . f e d e r a l , p r o v i n c i a l , i n d u s t r y , and u n i v e r s i t y l e v e l s . The r e l a t i v e s i z e of t h e d o m e s t i c r e s i d e n t i a l c o n s t r u c t i o n mar-k e t adds t o . t h e p r o b a b l e impact t h a t i n c r e a s i n g , s u b s t i t u t i o n w i l l have on the C a n a d i a n f o r e s t i n d u s t r i e s . I t i s mandatory f o r t h e f o r e s t , i n d u s t r i e s t o s e a r c h f o r more d i v e r s e m a r k e t s . a n d expand e x p o r t s t o many c o u n t r i e s t h r o u g h o u t t h e w o r l d . E x p o r t m a r k e t s can o f f e r c o n s i d e r a b l e scope f o r t h e C a n a d i a n s o f t w o o d lumber and plywood i n d u s t r i e s . W i t h w o r l d demand f o r wood p r o d u c t s f o r e c a s t t o i n c r e a s e s u b s t a n t i a l l y i n t h e f u t u r e , and the USSR and.Canada h o l d i n g t h e o n l y m a j b r . r e s e r v e s o f s o f t w o o d . t i m b e r , t h e f u t u r e p r o s p e c t s o f t r a d e e x p a n s i o n , appear t o be good. The s u c c e s s o f C a n a d i a n t r a d e m i s s i o n s t o Europe f o r t h e p r o m o t i o n o f wood frame c o n s t r u c t i o n has a l r e a d y begun to m a t e r i a l i z e i n t h e f o r m o f i n c r e a s e d lumber and plywood e x p o r t s t o t h e U.K., t h e , N e t h e r l a n d s , and. o t h e r West European c o u n t r i e s . F u r t h e r e f f o r t s i n t h i s d i r e c t i o n s h o u l d be g i v e n m a j o r emphasis b y . t h e f o r e s t i n d u s t r i e s . F o r l o n g , range p l a n n i n g , purposes,. i t i s n e c e s s a r y t o ..be aware o f - c h a n g i n g m a r k e t s and t h e i r ..nature. A d e c r e a s i n g , consumption, of wood p r o d u c t s i n r e s i d e n t i a l c o n s t r u c t i o n , . due t o . i n c r e a s i n g s u b s t i t u t i o n o f co m p e t i n g m a t e r i a l s , s h o u l d n o t have a d e v a s t a t i n g e f f e c t on t h e f o r e s t i n d u s t r i e s i f i t i s a n t i c i p a t e d b e f o r e h a n d . I n c r e a s e d e f f o r t i n b o t h p r o d u c t and market r e s e a r c h can e f f e c t i v e l y c u r t a i l o r s l o w down s u c h t r e n d s , and. e f f e c t i v e p l a n n i n g c a n . r e s u l t i n t h e development o f a l t e r -n a t i v e m a r k e t s f o r wood base d p r o d u c t s . B I B L I O G R. A P H Y Adamson, R. T. 1967. Urban growth and d e v e l o p m e n t — t h e gloomy- P o l y a n n a . A r c h . Can. 44(7 ) : 4 2 , 4 3 . 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