Slab Foundations Continue to Overtake Basements in New Homes
NAHB analysis of the latest Survey of Construction (SOC) shows the gap between slab and full/partial basement foundation adoption rates is growing: The share of new homes built on slabs steadily increased from 46% in 2000 to 65% in 2020, while the share of new homes with basements dropped from 36.8% to 22%.
There are large regional differences in foundation types across the nation. Homes in colder areas, where building codes normally require foundations to be built below the frost line, are predominately constructed with full or partial basements.
The division with the highest share of full/partial basements in new homes is New England (79.8%), followed by the West North Central division (77.2 %), the Middle Atlantic division (69.5%) and the East North Central division (54.3%).
New homes with slab foundations are most common in the West South Central (95.7%), South Atlantic (79.4%), Pacific (67.7%) and Mountain (48.1%) divisions. They are most popular in the West South Central division, where new single-family homes have been primarily constructed on slab foundations over the past 10 years.
A warmer climate makes building on slab more cost effective, compared to full/partial basements. Slab foundations also need the least amount of maintenance in the long run. In the East South Central division, 43% of new homes started in 2020 had a crawl space and 38% were built on slabs.
NAHB Senior Economist Na Zhao provides more analysis in this Eye on Housing post.
Latest from NAHBNow
Aug 29, 2025
NAHB's Monthly Update Features Canadian Lumber Duties Talking PointsThe update provides the latest messaging framework to help members articulate housing priorities and latest news related to the Canadian lumber imports and builder sentiment.
Aug 28, 2025
Podcast: Congressional Priorities and the Trump Economy Heading into FallOn the latest episode of NAHB podcast Housing Developments, NAHB CEO Jim Tobin and COO Paul Lopez discuss how the rest of the year looks as Congress gets ready to return to Washington next week.
Latest Economic News
Aug 29, 2025
Multifamily Absorption Rises in the Second QuarterThe percentage of new apartment units that were absorbed within three months after completion rose in the second quarter, according to the Census Bureau’s latest release of the Survey of Market Absorption of New Multifamily Units (SOMA).
Aug 28, 2025
Mortgage Rates Move Lower, Hitting 10-Month LowAverage mortgage rates in August continued their steady decline and are now at their lowest rate since last November.
Aug 27, 2025
Wood-Framed Home Share Increased in 2024Wood framing continues to dominate the U.S. single-family home construction market, according to NAHB analysis of 2024 Census Bureau data.