The Complex Rules for Creating New Housing in San Francisco
When the ADU (Accessory Dwelling Unit) program was introduced in San Francisco, it offered a creative path to build housing within existing structures. Arriving alongside the Legalization program, it gave property owners new options to bypass strict density limits.
However, years of piecemeal code exceptions have turned these programs into a tangled bureaucratic mess. Today, property owners trying to legalize an existing unit are often forced into the ADU program just to avoid exorbitant sprinkler costs. While ADUs offer the most advantages, they aren't always the best fit for every property owner—and navigating state vs. local rules, attached vs. detached designs, and as-of-right additions has become overly complex.
Sprinklers & Building Classifications: The State exempts 1-to-2 unit ADUs from sprinkler upgrades and prevents 2-unit buildings from reclassifying as 3-unit apartment buildings. Legalizations and as-of-right units do not receive this protection.
Exposure Standards: State ADUs and legalizations bypass standard open space exposure rules. Local ADUs receive a reduced footprint requirement ($9' \times 25'$), whereas as-of-right units must meet full SF Planning code ($25' \times 25'$).
Tenant Noticing Risks: Local ADUs require tenant notification, which can derail project timelines by up to 18 months if appealed through the Rent Board. Other programs skip this notice requirement.
Driveway & Curb Cut Fees: Both State and Local ADU programs permit property owners to keep front driveways when converting garage space. Legalizations and as-of-right projects require complete driveway removal alongside heavy Department of Public Works (DPW) and engineering fees.
A Call for Common-Sense Reform
You get the idea. The current system forces property owners and their designers to navigate competing local and state rules rather than simply focusing on adding safe, viable housing. We are calling on city legislators to establish a unified, streamlined set of regulations for all housing types created within existing buildings.
Reach out to your local Board of Supervisors member today and demand common-sense housing code reform!
Brought to you by Property Atlas.
Comments