The California law that virtually spells the end of single-family-home neighborhood zoning is not enough for San Francisco, where even more dense housing will be embedded into neighborhoods around the city.

City Supervisor Rafael Mandelman’s plan would expand SB9 to allow more units in single family home neighborhoods.

The San Francisco Chronicle reported on the war in single family homes 2.0:

Supervisor Rafael Mandelman’s plan would double down on the state’s goal to add more homes in existing neighborhoods by allowing up to four units on lots currently zoned for residential homes — and up to six units on corner lots.

Mandelman introduced his fourplex ordinance last summer. But the effort recently took on a new dimension after he accepted a recommendation from the Planning Commission that would upzone all single-family neighborhoods to allow duplexes, basically exempting San Francisco from SB9 because the law applies only to areas zoned for single-family homes. Mandelman and housing advocates endorsing his proposal say it would adapt SB9 to the city’s unique character.

The law also makes it easier to get a building permit. Under SB9, homeowners can build more units on their lots through a process known as ministerial approval, a streamlined review that removes city officials’ discretion to arbitrarily reject denser housing.

Mandelman’s plan does have critics, including the group that took its moniker from the group Never in My Back Yard — NIMBY adherents want to preserve single-resident neighborhoods. Yes in My Back Yard (YIMBY) oppose the plan, claiming the new process will hurt people who need affordable housing.

“It’s not a good enough trade-off,” Rafa Sonnenfeld, director of legal advocacy at YIMBY Law, said in the Chronicle report. “It’s the most basic way of getting around the law. I believe San Francisco has one of the longest review periods of any city in the state.”

Allowing San Francisco to skip the law’s expedited review process will make “bonus” units subject to local rent control and also won’t require new multi-unit properties on once-single residential lots to be owner occupied for three years.

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