252 



A NATIONAL PLAN FOR AMERICAN FORESTRY 



sheathing; nor does this take any account of the materials that may 

 displace wood lath and shingles, which are not measured as lumber. 



In multifamily housing the displacement of lumber by other 

 materials to date has been even more pronounced than in the single- 

 family dwelling. This type, which has developed almost entirely 

 since 1912, made up some 50 percent of new housing by 1928. New 

 multifamily housing is quite generally either of masonry-wall or all- 



320 



(Basis: Values for 1915= 100 Per Cent) 



1915 



27 



1931 



RESIDENTIAL 



(CONSTRUCTION 

 BASED ON SQ.FT. 

 OF FLOOR AREA) 



ACTUAL CONSTRUCTION, ALL CLASSES 



Simple average of structural steel bookings, 

 common brick bookings, Portland cement 

 Shipments, loadings of sand, gravel and stone, 

 shipments of face brick and enamel ware 



FIGURE 3. Construction trends: Residential and all classes as related to urban and total population. 



fireproof construction, and involves a reduction in floor area per 

 person. It is estimated that use of other materials and reduction of 

 floor area in multifamily housing reduced lumber requirements for 

 total new housing in 1928 by 20 or 25 percent per family as compared 

 with 1912. If multifamily housing alone can account for such a 

 decline, 25 percent would be a conservative estimate for the relative 

 displacement of lumber in single- and multiple-unit urban residential 

 construction during the period considered. 



