"Go West" may not be the best advice for someone in search of elbow room. The National Association of Home Builders (NAHB) says that housing lot sizes are shrinking everywhere, but they are smallest in the Pacific and Mountain divisions, and in the furthest west division of the South.
The median lot size for a new single-family detached home was 10,000 square feet in 1992. Ten years later it had fallen under 9,000 square feet but shot back up during both the housing boom and the housing crisis (our guess, because fewer lower priced homes were being built) before resuming a gradual but fairly steady decline. In 2015 the median size fell under 8,600 square feet for the first time since the advent of the Census Bureau's Survey of Construction (SOC). The 2017 survey puts the median lot size nationwide at 8,560 square feet, or just under a fifth of an acre, a 2 square foot decrease from 2016.
Natalia Siniavskaia, writes in NAHB's Eye on Housing blog that, while lots are getting smaller on average, the regional differences in lot sizes persist. Looking at single-family detached speculatively built (or spec) homes started in 2017, the New England census division stands out, with median lots twice as large as the nation as a whole.
Siniavskaia says New England is known for strict local zoning regulations that often require very low densities. Therefore, it is not surprising that more than half of single-family detached spec homes started in New England are built on some of the largest lots in the nation, with more than half of the lots exceeding 0.4 acre. The East South Central and Middle Atlantic Divisions are next on the list with the median lot occupying just slightly less than a third of an acre (0.3 acres).
The Pacific division, where densities are high and developed land is scarce, has the smallest lots, with half of the lots being under 0.15 acres. The neighboring Mountain division and the West South Central division also report typical lots smaller than a national median, 0.17 acres. This gives the latter division a much smaller lot size than the remainder of the South. The East South Central has a median of 0.3 acres and the South Atlantic median is 0.21 acres.
The author stresses that the analysis covers only homes built on spec. Where the home is custom built on an owner's land, whether by a general contractor or by the owner acting in that capacity, a professional land developer is not usually involved in subdividing the land so different terminology applies. Nevertheless, the SOC reports that custom homes tend to have much larger lots. The median size reported for homes started in 2017 is about 1 acre.
