Slab Foundations Continue to Overtake Basements in New Homes

Trends
Published

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.

Subscribe to NAHBNow

Log in or create account to subscribe to notifications of new posts.

Log in to subscribe

Latest from NAHBNow

Economics

May 23, 2025

Volatile Spring Selling Season Continues

Sales of newly built, single-family homes in April increased 10.9% to a 743,000 seasonally adjusted annual rate from a downwardly revised March number, according to newly released data from the U.S. Department of Housing and Urban Development and the U.S. Census Bureau. The pace of new home sales in April was up 3.3% compared to a year earlier.

Material Costs

May 22, 2025

NAHB Members Cite Impact of Tariff Uncertainty on Home Building

Tariff uncertainty from the Trump administration continues to impact home builders across the country, as builders prepare for potential price hikes and supply chain issues. NAHB members have been sharing the impact that these tariffs are having with media outlets across the United States.

View all

Latest Economic News

Economics

May 22, 2025

Existing Home Sales Fall in April

Despite the brief retreat in mortgage rates and increased supply, existing home sales dropped to 7-month low in April, according to the National Association of Realtors (NAR). This unexpected decline suggests buyers’ activity continues to be constrained by economic uncertainty and ongoing affordability challenges even with improved market conditions.

Economics

May 22, 2025

Income Growth Helps Mute Existing Affordability Constraints

Despite solid income gains and lower home prices, Americans still continue to face major housing affordability challenges, according to the latest data from the National Association of Home Builders (NAHB)/Wells Fargo Cost of Housing Index (CHI).

Economics

May 21, 2025

Gains for Multifamily Missing Middle over Last Year

The missing middle construction sector includes development of medium-density housing, such as townhouses, duplexes and other small multifamily properties.