San Mateo County Accessory Dwelling Unit (ADU) Standards
New laws were recently passed, and updates will be coming soon
INFORMATION | |
Contact |
William Gibson – 650.363.1816 |
Website | |
ADU Ordinance | |
STANDARDS | |
Zones allowed |
Bay side: all R zones except R-3 Coast side: R-1 |
Lot restrictions |
None |
Minimum lot size |
5,000 sf |
Min / Max ADU size |
None / 1,200 sq ft |
ADU building height |
26 feet |
Setbacks |
5 feet on all sides, unless:
|
Parking requirements |
For 0-2 bedroom units, one space is required and for 3+ bedroom units, two spaces are 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. Permeable paving is required.
|
Owner occupancy |
No requirement |
Sample fees from recently built projects* |
ADU 1 (626 sq ft, attached): $10,788*
ADU 2 (627 sq ft, detached): $6.577* *does not include school fee which varies by location and is $1.39-$3.48 / sf |
Other requirements |
|
Process |
A planning application is required. Making an appointment to meet with a planner in the initial stages of the project can help avoid challenges and is highly recommended. |
Exceptions |
None |
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