San Mateo discussing SB 9 zoning changes

Following the implementation of Senate Bill 9 in January, cities are attempting to blend its housing requirements around duplexes and lot splits with local needs. SB 9 requires cities to approve up to two residential units in single-family zoned areas, like duplexes, and to provide opportunities for lot split approval. The state passed the law in 2021 to help address the lack of housing in California. Under the law, San Mateo cannot deny eligible SB 9 projects unless it affects public health or safety. The council is narrowing down zoning code requirements around demolition limits, lot splits, ADUs, unit sizes, subdivision map extensions, and if public notice should be required for new developments.

Under the law, qualified duplex developments must be in a single-family zone, but not be in a historic district or property. It also must not demolish affordable housing, be occupied by a tenant in the last three years and destroy more than 25% of an exterior wall during construction. A duplex is a home with two units in the same building. A lot split would be two units per property for four units total, with cities allowed to add additional ADUs. The parcel would have to be a 60/40 split and be a minimum of 1,200 square feet. It would be for residential use only, with primary residency requirements for three years. However, the city has some leeway in going above state requirements or keeping with state standards.

The council ranged in opinions on how easy building on single-family lots should be. Mayor Rick Bonilla favored easing restrictions even more than state requirements. He suggested no demolition limit and flexibility in floor area units. He wanted more housing for individuals and families with kids, noting that the city needed units of all sizes ranging from homes to JADUs. The council has declared more housing a significant priority, particularly in transit areas.

“We are in a housing crisis. The whole point of this law is to allow us to build more housing. We’ve had a housing shortage since 1981,” Bonilla said.

Councilmember Amourence Lee prioritized helping families find housing with larger units and looking at R1 single-family zoning near transit corridors. She wanted to keep the demolition threshold consistent at 50% for greater development flexibility, which the council majority favored. The city currently requires a special use permit for demolition of 50% or more.

“I favor policies that would encourage the development of family-friendly units. [That’s] especially true with the lot splits. That will open up a new market for homeownership for missing middle who have really been priced out. I see a huge opportunity here,” Lee said.

Councilmember Joe Goethals acknowledged San Mateo had become a different community over the years. However, he stressed it was essential to make San Mateo housing available for all incomes and limit displacement. He favored a 50% demolition limit, above the state requirements.

Councilmember Eric Rodriguez favored keeping local guidelines at state minimums, given the many changes in single-family R1 zones. He liked limits of 25% for exterior wall demolition and anything above requiring a special use permit. He favored restricting ADUs and lot splits to state requirements and public notices to neighbors.

“I think it’s important to preserve as much local control as possible moving forward. State lawmakers built in flexibility so local jurisdictions can customize the ordinances to meet the needs of our residents,” Rodriguez said.

Vice Mayor Diane Papan favored the 50% demolition limit but was undecided about ADUs on lot splits and floor area units requirements.

“I’m not sure what lot sizes could actually tolerate that. It would get awfully cramped,” Papan said.

The council will have an additional study session to refine and discuss options.

curtis@smdailyjournal.com

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