Commission approves two‑family development at 428 Fifteenth with a state ADU after debate over rear‑yard tradeoffs

A West‑side demolition and infill project at 428 Fifteenth Avenue that had been pulled from consent drew extended discussion Dec. 1 over whether to require or encourage a state‑law ADU in order to maximize density. Planning staff recommended approval of a code‑compliant two‑family building with a detached, state‑law ADU in the rear yard and reported a site visit and historic‑preservation review that concluded the existing structure is not an "earthquake shack." Neighbors raised concerns about sun, backyard loss and potential foundation impacts; the applicant and architect described design constraints, easements and the decision to include a 253‑square‑foot ADU to add one unit of housing.

Key points and policy tradeoffs: Commissioners framed the decision as a policy tradeoff between preserving private open space and adding incremental housing. Commissioner Diamond and others expressed unease at requiring an ADU as a condition for approval without a citywide policy; the applicant said he preferred to move forward and was willing to include the ADU. Staff explained the ADU was added late in response to commissioner feedback seeking further densification and noted state ADU rules can differ from local ADU rules in their ability to waive rear‑yard requirements.

Historic and technical review: Preservation staff said they investigated the building and found insufficient evidence to classify it as an earthquake shack; the sponsor filed required SB 330 materials and the department’s review determined the building is not a historic resource under that process.

Decision and remainder: With the applicant’s assent and further commentary from commissioners about the need to clarify broader ADU policy, the commission approved the project (including the ADU) by unanimous vote and closed the hearing.