Home Building Construction Times Increased Year-Over-Year in 2021

According to the U.S. Census Bureau’s 2021 Survey of Construction (SOC), with further analysis provided by the National Association of Home Builders (NAHB), the average completion time of a single-family house in 2021 was approximately 8.2 months, which typically includes a little over a month’s time from authorization to start and another 7.1 months to complete construction. It took an additional 12 days more in 2021 than in 2020 to complete a home. The result of supply-side challenges which created building headwinds throughout the year.

Of course, the time from authorization to completion varies across the nation and depends heavily on the geographic location and whether the house is being built for sale or custom built. The geographical division with the longest building duration was New England (11.9 months), followed by the Middle Atlantic (11.7 months), the Pacific (9.6 months), the East South Central (9.5 months), the East North Central (8.5 months), the West North Central (8.3 months), and the Mountain division (8.3 months). These six divisions had average time from permit to completion exceeding the nation’s average (8.2 months). The shortest period, 7 months, is registered in the South Atlantic division. The average waiting period from permit to construction start varies from the shortest time of 23 days in the East North Central to the longest one of 51 days in Pacific.

The SOC also tracts and collects sale information for houses built for sale, including a sale date when buyers sign sale contracts or make a deposit. Looking at single-family homes built for sale and completed in 2021, 32.5% were sold before construction started, 43.2% sold while under construction, 12.7% sold during the month of completion, and 9.8 % sold after completion. The share of completed houses remaining unsold was 1.8%.