Skip to main content

Supervisors to consider citywide fourplex expansion next year

Facing a state mandate, San Francisco policymakers have their work cut out for them in figuring out how to get more housing built. 

Fourplexes may be one—albeit small—means of alleviating San Francisco’s chronic housing shortage as the city looks ahead to other possibilities, according to Supervisor Rafael Mandelman. 

This week, Mandelman introduced a proposal that would make any single-family housing lot eligible for conversion to a building of up to four units, a process that would otherwise undergo an onerous review process. It’s part of a package of proposals that Mandelman hopes will encourage production of smaller, multifamily residences in the city. 

“By the standards of the past, this is a relatively significant upzoning,” Mandelman told Here/Say. “Compared to what the moves that we’re going to need to make to meet our obligation…it’s relatively modest.” 

Under a state mandate called the Regional Housing Needs Allocation (RHNA), San Francisco will likely be required to build about 82,000 new housing units—suitable for varying income levels—between 2023 and 2031. 

Compared to the city’s pace of housing production in recent years, that’s a major boost: According to the Construction Industry Research Board, just 3,343 residential permits were approved in San Francisco in 2019, and 2,192 residential permits were approved last year. A state mandate of 82,000 units would equate to 10,250 new units per year. 

Mandelman’s newest fourplex proposal has the potential to increase density in parts of the city that skew heavily towards single-family homes.

Most of San Francisco’s densest neighborhoods are in the city’s eastern half. | Getty Images

 San Francisco’s densest neighborhoods are largely clustered in the eastern part of the city, with relatively few single-family homes in neighborhoods like Nob Hill, South of Market and downtown. The West of Twin Peaks area has the lowest percentage of multifamily housing, according to data from the Planning Department.

Allowing fourplexes everywhere would spread density more equally across the city, Mandelman said, compared to an earlier, more modest proposal to allow fourplexes only on corner lots.

The latter proposal will likely be reviewed at the Planning Commission and Board of Supervisors this fall, and the broader fourplex plan is expected to make its way through the same process by early next year. Another proposal by Mandelman to restrict construction of large, single-family residences will advance to the board in the coming weeks. 

If San Francisco moves to allow fourplexes everywhere, it would bring the city in line with Berkeley and Sacramento, both of which announced similar plans to liberalize construction of fourplexes. It remains to be seen how many of San Francisco’s 11 Supervisors will embrace the fourplex proposals. 

“I think San Franciscans understand that we have a housing crisis in California, and that we need to do our fair share to address that housing. So that’s where I think we need to start,” Mandelman added. “I think there will be concern and anxiety about this proposal, and I don’t imagine that everyone is going to immediately come on board…we’ll see where we land.” 

In the meantime, the Planning Department is hammering out a so-called Housing Element, or a plan to meet the expected mandate of 82,000 housing units by 2031. The department kicked off that discussion in April, and will take public input on the housing plan before fine-tuning and making it final in 2022. 

A pair of single-family homes in the Sunset District. | Getty Images

Other Supervisors have floated their own ideas for fourplex legislation, while Mayor London Breed has signaled a desire to bring a housing bill to the ballot. Breed’s proposal would make housing developments that fit within existing zoning and contain more than 15% affordable units subject to “by-right” approval, meaning that they bypass time-consuming and often costly reviews. 

At the state level, legislators proposed a flurry of housing bills aimed at eliminating various barriers to multifamily housing and hold cities accountable to their state-mandated housing targets. One bill proposed by San Francisco Assemblyman David Chiu, AB-215, would give the state oversight midway through each RHNA cycle and make better-performing cities eligible for state funding. 

Fourplexes are “a small piece” of San Francisco’s broader housing puzzle, Mandelman added. The board’s next task may be looking at areas where additional height can be added—in particular near transit—or other means of relaxing land use controls in San Francisco. The board as a whole is going to have to grapple next year and the year following with even bigger proposals probably coming out of [the Planning Department] to address the housing shortfall,” he said.