Forking Linda_D's excellent post from the affordable housing thread:
The economic boom after WWI saw the massive growth of America's middle class. At the same time, automobiles became affordable, more reliable, and usable (electric starter, heated passenger compartment, standardized transmission shifting, regular sources of fuel); they made the leap from toys to appliances. Many of the things we associate with the 1950s -- consumerism, auto ownership, and the emergence of the single family house as the American Dream -- became part of our collective consciousness nearly 100 years ago.
When I'm back home in Buffalo, I'll sometimes go to the main branch of the Buffalo and Erie County Public Library, and look through the microfilm reels of old newspapers. The real estate ads tell a story of an emergent suburbia. Before WWI, ads for subdivisions -- usually just improved lots alone -- were full of text, and offered directions to the site via streetcar and interurban. The ads changed dramatically after WWI. There were more developments comprising of speculative-built houses, and "bring your builder" became the exception. As the 1920s progressed, ads increasingly featured driving directions to a site, and directions via streetcar disappeared, even though the network hadn't begun to contract. The sales pitch also changed, from "escape the smoke" and "land in this area will only appreciate in value" to "good schools" and "nearby parks". The ads grew slicker as the 1920s advanced, with photos, sketches, and appeal to upscale aspirations.
I like to use Tonawanda, New York, a suburb of Buffalo, as an example of 1920s suburbia. About half of the town was subdivided and improved in the 1920s. Most of the new lots were in the 45' to 80' range.
Development stalled in the real estate crash of 1927, and little took place for nearly 20 years. After WWII, with material shortages over and demand for housing at an all-time high, the once-nearly abandoned streets came back to life. The town's housing stock is mainly fromt he 1950s and 1960s, but the lots they were built on were platted decades earlier.