According to the National Association of Home Builders, the average size of a new single family house was 1,500 square feet in 1970. However the average home built in the past 5 years was sized at more than 2,400 square feet.
Roughly 35 percent of single-family houses built in 2010 in the U.S. had four or more bedrooms, an increase from the previous year after a four year decline. The share of homes built with …