In the second quarter of 2018, the average size of a single-family home was 2,555 square feet, continuing the trend of diminishing house size that started in 2016, per NAHB data.
Looking at the data based on a one-year moving average after cycle lows, single-family homes' average size nine percent more square footage, and the median size is 13 percent larger, according to the National Association of Home Builders. NAHB economist Robert Dietz points out that single-family homes historically get larger in the wake of a recession, and grow smaller before and during a recession, "This pattern was exacerbated during the current business cycle due to market weakness among first-time homebuyers and supply-side constraints in the building market."
But the recent declines in size indicate that this part of the cycle has ended, and size will trend lower as builders add more entry-level homes into inventory. In contrast to single-family patterns, new multifamily apartment size is down compared to the pre-recession period. This is due to the weak for-sale multifamily market and strength for rental demand.