One California law was supposed to flip defunct strip malls across California into apartment-lined corridors.

Another was designed to turn under-used church parking lots into fonts of new affordable housing.

A third would, according to supporters and opponents alike, “end single-family zoning as we know it.”

Fast-forward to 2025 and this spate of recent California laws, and others like it intended to supercharge the construction of desperately needed housing, have had “limited to no impact on the state’s housing supply.”

That damning conclusion comes from a surprising source: A new report by YIMBY Law, a pro-development nonprofit that would very much like to see these laws work. 

The analysis, released today, studied five state laws passed since 2021 that have swept away regulatory barriers to building apartment buildings and other dense residential developments in places where such housing has been historically barred. 

The laws under review include:

• SB 9 from 2021, which allows people to split their single-family homes into duplexes, thus ending single-family-home-only zoning across California. In practice, according to the report, building permits for only 140 units were issued under the law in 2023.  
• AB 2011 from 2022 was designed to make it easier for developers to convert office parks, strip malls and parking lots into apartment buildings. In 2023, developers on just two projects were given local regulatory approval to start work under the law. In 2024, the total was eight. The report found no projects that have made use of SB 6, a similar bill passed that same year but with stricter labor requirements.
• SB 4 from 2024, the so-called Yes In God’s Backyard law, which lets churches, other houses of worship and some schools to repurpose their land for affordable housing. The report found no takers on that bill too.

“It’s grim,” said Sonja Trauss, executive director of YIMBY Law. Though she acknowledged some of the laws are still new, she blamed their early ineffectiveness on the legislative process which saddled these bills with unworkable requirements and glaring loopholes. 

“Everybody wants a piece,” she said. “The pieces taken out during the process wind up derailing the initial concept.”

What are these requirements and loopholes that have prevented these laws from succeeding? Maybe not surprisingly, they are the frequent objects of critique by YIMBY Law and the Yes In My Backyard movement more generally. 

One is the inclusion of requirements that developers only hire union-affiliated workers or pay their workers higher wages. 

Another are affordability mandates which force developers to sell or rent the units they build at below-market prices.

A third is the strenuous opposition by local governments and the failure of these state laws to override it. In the two years following the passage of SB 9, for example, YIMBY Law tracked 140 local ordinances that, in the view of the report, were “designed to reduce or prevent” the bill from working on the ground. They included tight limits on the size of buildings, affordability requirements, or restrictions on which types of owners can make use of the law. 

Last year, the state Legislature passed a “clean up” bill meant to void some of these local add-ons.

There are plenty of other possible impediments to construction in California, which may explain why these bills have seen such tepid uptake. Sky high interest rates, chronic shortages of construction workers and high material costs (all of which could be exacerbated by current or expected changes to federal tariff, immigration and fiscal policy) all work to make residential housing development a less appealing financial proposition. Insufficient public funds and expected cuts to federal housing programs may weigh down on the affordable housing sector too.

But the report is not the first to point to the preconditions and omissions included in so many of the state’s legislative efforts to goose housing development as the reason for their lack of impact.

In a recent law paper, UC Davis law professor Chris Elmendorf and UC Santa Barbara political scientist Clayton Nall wrote that the relative success of California’s efforts to boost the construction of accessory dwelling units is the exception that proves the rule. Over the last decade, a cavalcade of state laws have stripped local governments of their ability to subject backyard cottage projects with environmental review mandates, significant fees, affordability mandates, union-hire rules, confining size or aesthetic limitations or added parking requirements. 

“The ADU boom stands alone. No other form of housing production took off in California during this period,” the authors wrote. A likely reason why, they argue, is that ADU projects don’t come with nearly as many strings attached as other forms of dense development permitted by various California laws.

In 2023, the state permitted more than 28,000 ADUs, according to state data.

The history of ADU legislation in California is instructive, said Trauss. “It took about like five years of revisions before they were really getting going.”

The YIMBY Law report is based on self-reported permitting data submitted by cities and counties to the California Housing and Community Development department. The nonprofit complemented that messy database with its own internal collection harvested from its own litigation and activism. That means the data on what is actually getting built — and therefore how effective any of these laws really are — is imperfect. 

That fact isn’t lost on many legislators. 

The Assembly housing committee’s first hearing of the year was dedicated not to new legislation, but to evaluating the state’s existing “pro-production” laws.

“We shouldn’t just keep passing more and more bills just because we can,” Chair Matt Haney, a San Francisco Democrat, said. “We should actually look at what is working, why it’s working, how we can do more of what’s working and if it’s not working, we should do more to fix it or change it.”