California Sees Spike in ADU Permits

Homeowners in the state are eagerly taking advantage of new laws allowing them to build additional housing units, making a small but significant impact on the housing supply.

2 minute read

May 29, 2023, 7:00 AM PDT

By Diana Ionescu @aworkoffiction


Small grey accessory dwelling unit cottage in California backyard

City of Salinas / Accessory dwelling unit

The liberalization of laws surrounding the construction of accessory dwelling units (ADUs), also known as granny flats, is starting to make a significant dent in California’s housing crisis. While far from a panacea, the flurry of permits issued for ADUs signal that homeowners across the state are eager to take advantage of the opportunity to build an extra housing unit on their property.

As Erica Werner explains in The Washington Post, “More than 23,000 ADU permits were issued in California last year, compared with fewer than 5,000 in 2017 — which was around when ADU permitting began to take off thanks to legislative and regulatory changes in the state.” Los Angeles issued 7,160 of those permits, while only issuing 1,387 permits for single-family homes in the same time period.

Despite the high cost of ADU construction—the average unit runs roughly $300,000—“a study from the NYU Furman Center found that ADUs are being built not in the wealthiest neighborhoods, but more often in low- to middle-income areas, and often in places with relatively good access to jobs.” According to study author Christopher Elmendorf, “‘That’s consistent with the theory that this is a viable form of development in places that you may not’ otherwise be able to easily build.” David Garcia, policy director for the Terner Center for Housing Innovation at the University of California at Berkeley, says the speed at which Californians are applying for ADU permits signals “a pent-up demand from homeowners to want to do more with their land.”

Sunday, May 21, 2023 in The Washington Post

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