In the Golden State’s ongoing civil war over housing, two pieces of legislation that went to Gov. Gavin Newsom’s desk last week were more like a skirmish than a major battle. But one of them has already gained the attention of White House economists, who included it yesterday in a call to action to build more housing across the nation.
Once Newsom signs the bills, known as SB 9 and SB 10 — and there are no indications so far that he won’t — they will amount to a victory for advocates of more density. They could also have an effect in San Francisco, where a local version of the new bills must overcome the city’s traditional anti-housing bloc of community activists and wealthy homeowners.
While sweeping overhauls of zoning and property taxes continue to suffer defeat at the state level, housing advocates have done better by loosening restrictions one screw at a time, as The Frisc reported earlier this year.
Proponents of the new state bills are downplaying their potential impact. “This is a gentle density increase that respects the character of neighborhoods,” state Senate President pro Tempore Toni Atkins, referring to SB 9, told the New York Times last week. Atkins is the author of SB 9.
The White House’s economists, whose new paper is a wealth of housing statistics in favor of zoning reform, called SB 9 “a welcome development” among a growing list of efforts across the nation with “much-needed potential to increase the housing supply.”
A plex flex
SB 9 will chisel away at the bedrock of California residential geography: the single-family house. In the Bay Area, more than 80 percent of residential land is zoned only to allow one single-family home per lot.
Property owners would be allowed a modest increase under SB 9: They can put up a duplex if they want. They also can split their single-family lot into two, and each can have a duplex. Theoretically, a lot with one home can turn into four.
To be clear, no one will be forced to build more densely on their property; SB 9 just removes the restrictions. (There are a few caveats: The looser rules won’t apply in historic districts, high fire risk areas, and more.)
Today’s vast swaths of single-family zoning are a legacy of racist policies that stretch back a century. (Berkeley is widely acknowledged as the first example.) Reform is a way to right those historic wrongs, proponents say. The trick is how to do it without perpetuating displacement; as The Frisc reported earlier this year, researchers are starting to dig into reforms to examine what works, and what doesn’t.
Housing advocates realize that blocking new homes hasn’t slowed gentrification. But Atkins and others are attuned to the sensitivity of the issue. When she describes SB 9 as “gentle,” she’s not just trying to stay under the radar. One analysis, from the UC Berkeley Terner Center for Housing Innovation, estimates the bill’s effect just as modestly.
Across California’s 7.5 million lots zoned for single-family use, SB 9 would enable 700,000 additional units to be “market feasible” — that is, the economics of building them would make sense for the owners. “Relatively few new single-family parcels are expected to become financially feasible for added units as a direct consequence of this bill,” the study’s authors write.
Here in SF, where there are more than 94,000 single-family lots, the study estimates SB 9 could spur the addition of 8,500 units. That’s not much, given that the Planning Department last year said SF needed 150,000 new units by 2050 for any chance of being once again a diverse and affordable city. And by California’s regular assessment of the state housing shortage, SF needs to build 82,000 homes in the next decade to meet demands or face loss of local control. (The 69,000 units in the city pipeline at the end of 2020 will fall well short; many will never come to fruition.)
Despite the daunting numbers, incremental changes are important too. Major developments proposing thousands of new units like Parkmerced (5,600 units) are rare — and one of the city’s largest, the Hunters Point Shipyard, is beset by environmental concerns.
SB 9 will offer another tool to increase density, proponents say, and it will be almost impossible for municipalities or neighbors to stop owners from using it. That’s a notable victory in a state that only built 100,000 new homes last year, despite an ongoing housing and homelessness crisis that no population exodus (as much as there really was one) could blunt.
A similar incremental approach has begun to pay off with a host of state laws passed in the past decade. (You can find a summary of many of these laws here.) One, for example, allows extra units on single-family properties, like “granny flats” in basements or detached dwellings in backyards. Another lets developers boost the size of projects beyond local restrictions if they meet a certain threshold of affordable units.

Potentially 10
At first blush, the second housing bill now on the governor’s desk, SB 10, seems more far-reaching. It would allow certain lots near public transit or already in dense urban areas to be rezoned for up to 10 units — a move to discourage car use and add muscle to California’s promise to address climate change.
But SB 10 maintains local control; it only applies in municipalities where legislators vote for it. And in doing so, they have leeway to add extra hoops that builders must jump through, like “discretionary review,” which takes approval out of the hands of planners and departments so politicians vote on specific projects. State Sen. Scott Wiener, who wrote SB 10, said on Twitter this week that local governments can also add affordability requirements as they see fit.
SB 10, however, eliminates one major blocking tactic currently available to housing opponents: the California environmental review known by the acronym CEQA.
So what’s the chance of SF’s Board of Supervisors enacting a local version of SB 10? One supervisor, Dean Preston, has already objected to it on Twitter. (Wiener’s affordability note came in response to Preston, who’s active on the platform.)
Preston makes no bones about opposing any market-rate development, so that leaves six of the other 10 supervisors to convince.
One of those supervisors, Rafael Mandelman, is making a push to allow up to four units of housing on all residential lots. Once signed by the governor, SB 10 could help that effort, according to Jack Persons, an aide to state Sen. Wiener: “SB 10 allows for up to 10 units, but it can also be just four units,” he says.
An earlier version of Mandelman’s reform, announced in February, is confined to corner lots and areas near transit hubs, but the newer, more ambitious version could get a bigger boost from SB 10’s elimination of environmental review.
UPDATE: Mandelman’s office has asked the City Attorney to weigh in on the effect and the timing, according to legislative aide Jacob Bintliff. “I don’t expect an answer on that until sometime in October,” Bintliff tells The Frisc.
Affordability — that is, whether someone building four units on a residential lot must reserve one or more units for lower-income residents — will likely come into play. We will see, once again, how much people who profess to strive for a more affordable, inclusive San Francisco are actually willing to allow enough housing to make it so.
Alex Lash is editor in chief of The Frisc.
An updated version of this story clarifies that two versions of Mandelman’s ordinance have been introduced.

