The average length of time to complete construction of a multifamily building, after obtaining authorization, was 14 months according to the 2015 Survey of Construction (SOC) from the Census Bureau. The permit-to-completion time increased by approximately one month from 2014 to 2015, as per unit median square footage and share of multifamily for sale rose.
The average time to build multifamily housing varies with the number of units in the building. In 2015, buildings with 20 or more units took 16.2 months to complete from the time of obtaining permits, whereas properties with 10 to 19 units typically finished in 14 months, and 5 to 9 unit buildings came in at 13.2 months. Lastly, 2 to 4 unit buildings required only 12 months.
The 2015 SOC data also shows a significant regional variation in the average construction duration of multifamily buildings. The Northeast had the longest time from authorization to completion, 15.8 months, followed by the South, 14.4 months, and the West 13.1 months. The shortest permit-to-completion period happened in the Midwest with 12.4 months.
Finally, there is regional variation based on property size as revealed in the chart below.