In the United States, Canada, and Australia, the end of World War II marked the beginning of a sustained period of elevated birth rates per thousand in the population. This rise reflected the relief from the hardships of the Great Depression of the 1930s and WWII, increased levels of immigration (immigrants tend to be younger and hence more fertile than average), and a protracted period of postwar economic prosperity. The rate of births in the United States rose from 18.7 per thousand in 1935 and 20.4 per thousand in 1945 to 24.1 per thousand in 1950 and a peak of more than 25.0 per thousand in 1955–1957. Twenty years later, when the babies born during the period 1946–1964 entered adulthood, the housing industry experienced a surge in demand that led to a period of high sales of new homes. The rate of new housing starts in this period rose from 20.1 per thousand of population in 1966 to a peak of 35.3 per thousand in 1972 and remained elevated, except during the economic recession of 1974–1975, until the end of the 1970s.

Another demographic effect on the housing industry arising from the post-WWII Baby Boom came from the children of the Baby Boom generation (the so-called Echo Boomers). The Echo Boomers started to enter their most fertile years in the late 1970s and caused an increase in the number of births per thousand from a post-WWII low of 14.8 in 1975 to a peak of 16.7 in 1990. The Echo Boomers did not have as large an effect on housing demand 20 years later as their parents had had, but there was still a significant increase in new housing starts from 13.7 per thousand in 1995 to a high of 18.8 per thousand in 2005; easily available mortgage financing contributed to the increase.