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

Portland Bus Lane

‘Forward Together’ Bus System Redesign Rolling Out in Portland

Portland is redesigning its bus system to respond to the changing patterns of the post-pandemic world—with twin goals of increasing ridership and improving equity.

August 30, 2023 - Mass Transit

An aerial view of Milwaukee’s Third Ward.

Plan to Potentially Remove Downtown Milwaukee’s Interstate Faces Public Scrutiny

The public is weighing in on a suite of options for repairing, replacing, or removing Interstate 794 in downtown Milwaukee.

August 27, 2023 - Milwaukee Journal Sentinel

Conceptual rendering of Rikers Island redevelopment as renewable energy facility

Can New York City Go Green Without Renewable Rikers?

New York City’s bold proposal to close the jail on Rikers Island and replace it with green infrastructure is in jeopardy. Will this compromise the city’s ambitious climate goals?

August 24, 2023 - Mark McNulty

A rendering of the Utah City master planned, mixed-use development.

700-Acre Master-Planned Community Planned in Utah

A massive development plan is taking shape for lakefront property in Vineyard, Utah—on the site of a former U.S. Steel Geneva Works facility.

August 31 - Daily Herald

A line of cars wait at the drive-thru window of a starbucks.

More Cities Ponder the End of Drive-Thrus

Drive-thru fast food restaurants might be a staple of American life, but several U.S. cities are actively considering prohibiting the development of new drive-thrus for the benefit of traffic safety, air quality, and congestion.

August 31 - The Denver Post

Air pollution is visible in the air around high-rise buildings in Dhaka, Bangladesh.

Air Pollution World’s Worst Public Health Threat, Report Says

Air pollution is more likely to take years life off the lifespan of the average human than any other external factor, according to a recent report out of the University of Chicago.

August 31 - Phys.org