With the end of 2020 approaching and a vaccine now being deployed, NAHB’s Eye on Housing is reviewing the posts that attracted the most readers over the past, dramatic year — a year that saw housing emerge as a bright spot for an economy under stress.

In September, the NAHB Economics team examined the time required to build a single-family home in 2019. During 2020, commentary in our industry surveys suggests this time expanded, as delivery times for building material grew.

The 2019 Survey of Construction (SOC) from the Census Bureau shows that the average completion time of a single-family house is around 8.1 months, which usually includes a little over a month from authorization to start and another 7 months to finish the construction. The average time to build a single-family home has been on an upward trend since 2014 when it took around 7 months. The time from authorization to completion varies across the nation and depends on the geographic location, and whether the house is built for sale or custom-built.

Among all single-family houses completed in 2019, houses built for sale took the shortest amount of time, 7.0 months from obtaining building permits to completion, while houses built by owners (custom builds) required the longest time, 13.5 months. Homes built by hired contractors normally needed around 9.8 months, and homes built-for-rent took about 12 months from authorization to completion.

Single-family homes built by contractors on owners’ land began construction within the same month after obtaining building authorizations. Custom homes built for sale and built by owners serving as general contractors had one month or a little over one-month lag between obtaining permits and the start of construction. However, single-family homes built for rent took the longest time, almost two months, from authorization to completion in 2019.

The average time from authorization to completion also varies across divisions. The division with the longest duration was the Middle Atlantic (12.3 months), followed by New England (11.9 months), the Pacific (9.8 months), the East South Central (9.0 months), the East North Central (8.7 months) , and West North Central (8.2 months) in 2019. These six divisions had average time from permit to completion exceeding the nation’s average (8.0 months). The shortest period, 6.9 months, is registered in the South Atlantic division. The average waiting period from permit to construction start varies from the shortest time of 20 days in the Mountain and the East South Central division to the longest one of 43 days in Pacific.

The SOC also 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 2019, 27.7% were sold before construction started, 32.7% sold while under construction, 13.9% sold during the month of completion, and 20.5 % sold after completion. The share of completed houses remaining unsold was 5.2%.