South San Francisco Accessory Dwelling Unit (ADU) Standards

        New laws were recently passed, and updates will be coming soon

Rozalynne Thompson – 650.377.8535
ADU Ordinance

Zones allowed

RL-8 SFD or wherever a SFD is constructed
Lot restrictions


Minimum lot size


Min / Max ADU size

Min: None

Max attached: 50% of primary dwelling with a max of 900 sf

Max detached: 900 sf

ADU building height

28 feet


5 feet rear and side, minimum 6 feet between ADU and primary dwelling
Parking requirements
One space is required unless state exemptions are met (ADU is within 1⁄2 mile of transit, in existing structures, in historic districts, within one block of car share locations, or in an area with residential parking permit rules that do not allow second units to get a permit). Tandem parking and parking in setbacks is allowed. Exceptions may be granted for accessibility considerations.
Owner occupancy

Owner must live in the main dwelling or the ADU

Sample fees from recently built projects*
ADU 1(429 sf, attached): $5,928
ADU 2 (640 sf, above garage): $6,997
Other requirements
Building Permit submittal only. Making an appointment to meet with a planner in the initial stages of the project can help avoid challenges and is highly recommended.
Appeal process or waiver and modification are at the discretion of the Chief Planner.

Disclaimer: standards and process may vary. Consultation with the contact is recommended before starting any project.

*Fees are specific to each project and will vary. Fees change regularly. These are provided as examples only.

Download ADU Standards PDF

Updated: 12/11/2017