San Mateo County
San Mateo County ADU rules
San Mateo County has an official local rule record in this scrape. Provider research is grouped at the San Mateo County level.
Local rule facts
Min/max ADU size
Min: 150 square feet Max detached: not to exceed 800 square feet or 35% of primary residence, up to 1,500 square feet Max attached: not to exceed 800 square feet or 50% of primary residence, up to 1,500 square feet Max JADU: 500 square feet *Additional 150 square feet...
Height
26 feet; ADUs entirely within a primary residence may be the height of that residence. *Two-story ADUs allowed.
Setbacks
Side and rear: 4 feet. Front: per underlying zoning district. Minimum separation: 5 feet, can be reduced with firewalls.
Parking
JADUs: No parking required ADUs: One spot may be required (tandem allowed). Outside of designated Midcoast areas, no parking required if: ½ mile walking distance from public transit, in a historic district, or one block from a car-share vehicle or ADU is within...
Owner occupancy
ADUs: none JADUs: owner occupancy required No short term rentals allowed
Process
-at-a-Glance FAQs Floorplans Inspiration Glossary Guidebook + Exercises Pre-Designed Plans Process-at-a-Glance See the resources page Events About Contact Getting Started Learning the Rules Budgeting Design Permitting Construction Renting Getting Started Learning the...