Where are the Largest Homes Built?

We previously reported a declining trend in new single-family home size that is likely to reverse during the post pandemic years. NAHB’s analysis of the 2019 Survey of Construction (SOC) data shows the pre-Covid19 trend of declining home size has been universal across the US regions. Nevertheless, regional differences in new home sizes exist with some of the largest single-family spec homes built in the Middle Atlantic and some of the largest custom homes built by contractors in the Mountain division.

Looking at single-family homes started in the US in 2019, median square footage (including finished areas of the basement and attic) was 2,300 square feet. Some of the smaller new homes were started in the West North Central division and New England where completely finished floor space in half of new single-family homes was 2,000 and 2,100 square feet or less, respectively. Some of the largest homes were started in Middle Atlantic where median square footage was 2,500 square feet.


Square footage differences are substantial between single-family attached (SFA) and detached (SFD) homes. Nationwide, the median square foot area of completely finished floor space is 2,400 square feet in SFD homes and 1,800 square feet in SFA homes. The Middle Atlantic stands out for building some of the largest attached (2,400 square feet) and detached (2,600 square feet) homes. Notably, new SFA homes started in the Middle Atlantic have square footage on a par with new detached homes in the US.


New England – where new single-family attached homes are more common than in any other division (26.6% of 2019 single-family starts vs US average of 12.5%) – reports a median square footage for attached homes of 1,800 square feet, 400 feet smaller than the median square footage of locally built SFD homes.

Additional variation in new homes sizes can be seen when comparing spec homes vs custom homes built by contractors and owners. Nationwide, new single family homes built by contractors tend to be larger with the median square foot area of completely finished floor space of 2,400 square feet. Homes built by owners tend to be smaller, with half of them reporting square footage of 2,000 square feet or less. New single-family homes built for sale are similar in size to homes built by contractors with the median square footage of 2,300 square feet.

The Mountain division stands out for reporting some of the largest contractor-built homes. Half of these custom homes started in 2019 have completely finished floor space of 3,000 square feet or more. In comparison, custom homes built by owners in the same division report median square footage of 2,300. Though substantially smaller than custom homes built locally by contractors, these are some of the largest owner-built homes in the nation.


The Middle Atlantic region is notable for building some of the largest built for sale SFD homes. Half of spec homes started here in 2019 have square foot area of completely finished floor space of 2,700 square feet or more. The West North Central division reports the smallest spec homes, with the median square footage of 2,100 square feet. Outside of these two extremes, there is surprisingly little regional variation in the median size of built for sale SFD homes. Five out of nine divisions show the median square footage of 2,400 square feet and additional two divisions report the median of 2,300 square feet.

Similarly, when looking at SFD custom homes built by contractors, there is less regional variation that one might have expected. Five out of nine divisions report the identical median square footage of 2,400 square feet. Additionally, many divisions report similar square footage medians for SFD homes built for sale and by contractors.

For this analysis, the median home size is chosen over average since averages tend to be heavily influenced by extreme outliers. In addition, the Census Bureau often masks extreme home sizes on the public use SOC dataset making it difficult to calculate averages precisely, but medians (as the midpoint of a frequency distribution) remain unaffected by these procedures.