Characteristics of New Single Family Homes in US? Want to know the type of foundation most common in your part of the country? In the total US, it is 39% basements, 30% slab and 30% crawlspace. BUT by region, there is a big difference. In the Northeast, it is 68% basements, 22% slab and 11% crawlspace. Midwest is 71% basement, 24% slab and 5% crawlspace. In the South 10% basements, 75% slab and 16% crawlspace. The West is 26% basements, 45% slab and 29% crawls pace. The average sq footages, # of stories, and a ton of other information is available here. Why should we care? For one thing, we PAY to have these studies done and second, if you are moving to a different part of the country, you may want to see what is typical there so you are prepared.