Analysis: California’s Single-Family Zoning ‘Killer’ Barely Making a Dent So Far

Senate Bill 9, approved by the California State Legislature to much fanfare in 2021, has had little impact on the way local governments do development business, according to a recent analysis by researchers at the University of California.

2 minute read

January 22, 2023, 11:00 AM PST

By James Brasuell @CasualBrasuell


California’s Senate Bill 9 (also known as the HOME Act) took effect on January 1, 2022, making it possible for homeowners to build up to four homes on a single-family parcel. YIMBYs described the approval and implementation of SB 9 as a milestone victory for zoning reform, while homeowner and neighborhood groups describe the bill as a death knell for existing communities.

So far, neither prediction seems clairvoyant, according to a recent analysis by researchers at the Terner Center for Housing Innovation at the University of California, Berkeley.

David Garcia and Muhammad Alameldin write an article sharing the findings of their analysis, describing SB 9’s impact as limited: “Some of the state’s largest cities reported that they have received just a handful of applications for either lot splits or new units, while other cities reported none.”

The article includes a table quantifying SB 9’s effects in 13 jurisdictions around the state. For example, the city of Berkeley, which has made news in recent years for planning to eliminate single-family zoning and removing parking requirements for residential properties, received one application for a lot split and five applications for SB 9 housing between January 1 and November in 2022 and approved none of them. The tables includes similarly lackluster results for Anaheim, Bakersfield, Burbank, Danville, Long Beach, Los Angeles, Sacramento, San Diego, San Francisco, San José, Santa Maria, and Saratoga.

“Among our sample, the smaller cities of Saratoga and Danville stand out for having a relatively higher number of SB 9 applications. Saratoga reported 15 applications for SB 9 units and 21 applications for lot splits in 2022. By comparison, the city permitted 71 total units of housing in 2021. Likewise, the city of Danville reported receiving 20 applications for lot splits, though no applications had been received for new units,” write Garcia and Alameldin, speculating that the two cities’ accomplishments are explained by larger residential lots in the city.

Based on the lackluster results so far, the article suggests that adjustments might be necessary to ensure SB 9 lives up to its potential for alleviating the state’s housing affordability crisis.

The Terner Center and other observers in the state did predict that SB 9 and its companion bill, SB 10, would have little impact on land use outcomes in the state.

Wednesday, January 18, 2023 in Terner Center for Housing Innovation

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