Where is housing slow to build?

Evan Soltas has a big first-of-its-kind paper measuring permitting and construction durations for standardized housing projects across 60 US cities from 2000 to 2025: A standardized 20-unit apartment building takes 4.6 years from permit submission to completion in coastal cities like LA, New York, and San Francisco, but just two years in Sunbelt cities like Raleigh, Orlando, and Phoenix. The fastest cities finish entire multifamily projects in the time the slowest cities take to merely approve a permit. Across cities, each additional year of permitting time is associated with 39% higher rents, an economically and statistically huge relationship that survives controls for income, density, and neighborhood characteristics.

Tragically, permitting is getting slower: the probability that a multifamily project gets approved within six months fell from 71% in 2000 to 44% in 2025, holding project characteristics fixed. Construction time fluctuates with the business cycle but shows no secular trend…in other words, the problem is permitting, not building. This paper is the knockout blow the YIMBY movement has been missing: systematic evidence that permitting generally, and permitting delay specifically, does indeed belong in the “growth control toolkit” hall of shame as a first-order regulatory driver of housing costs alongside zoning. Beyond the paper’s findings, I like to note that obvious out-of-pocket carrying costs during development aren’t the only source of permitting time project savings: Because of the pure time value of money, moving the exact same cashflows forward in time mechanically increases returns and project viability even if carrying costs are zero.