Figure 6.1 



New Housing Unit Production by Type of Unit, 1920-78, with Projections 

 (Medium Level) to 2030 



Thou. Units 

 3,000 r 



2,500 



|A; ; ./-... \..., 



2 QQQ ;'! V. : \ Mobiles .- 



1,500 



1,000 



500 



Multifamily 



One-Family 



± 



± 



J 



1920 1930 1940 1950 1960 1970 1980 1990 2000 2010 2020 2030 



mobile home emerged as a significant source of new 

 housing units. Its share of total demand grew to over 

 21 percent in 1972 before dropping to 12 percent in 

 1977. 



Single-family houses are typically occupied by 

 husband-wife households with heads in the middle 

 age classes. Over 85 percent of all such households 

 with heads between ages 35 and 54 lived in single- 

 family housing in 1976. Income also influences Jious- 

 ing type. In 1976 nearly 80 percent of all married 

 couples with incomes over $20,000 lived in single- 

 family houses. Occupancy of multifamily units and 

 mobile homes has been the highest among the 

 younger age classes and persons over 65. Households 

 headed by these age classes are generally smaller and 

 are likely to have somewhat smaller incomes. 



Because of prospective shifts in the age distribution 

 of the population, and the associated changes in fam- 

 ily type and income, the medium projection of 

 demand for single-family units averages nearly 1.7 

 million units a year in the 1980's (table 6.1, fig. 6.1). 

 In the following decades, there is a slow decline to 

 about 1.2 million units a year in the 2020-2029 



decade. Multifamily demand is projected to move up 

 moderately in the early 1980's to 570,000 units a year, 

 about 25 percent of conventional housing produc- 

 tion, before declining again in the late 1980's and 

 1990's. After the mid-1990's, the outlook changes and 

 multifamily units again become more important as 

 the second generation effects of the post-World War 

 II "baby boom" are felt. Demand for mobile units 

 remains relatively constant at 300-340,000 units a 

 year through the projection period. Most of these 

 units will be produced for primary residential use and 

 are expected to become larger and more houselike. 



In addition to the timber products consumed in 

 production of new residential units, substantial 

 volumes are used annually for the upkeep and 

 improvement of existing units. Between 1960 and 

 1977, the years for which reliable data are available, 

 expenditures for upkeep and improvements increased 

 moderately from about $15 billion to $20 billion 

 (1972 dollars). For the purposes of this study, it was 

 assumed that expenditures would grow in the projec- 

 tion period at about the same rate as the housing 

 inventory. Under this assumption, the medium pro- 



199 



