San Mateo County

Millbrae ADU rules

Millbrae 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 one bedroom or less: 850 square feet, two + bedrooms: 1000 square feet Maximum 50% of main home floor area. Max JADU: 500 square feet

Height

ADU: Attached – 25 feet; detached – 16 feet, JADU: same as the existing structure

Setbacks

Attached: side and rear – 4 feet, front – determined by base zoning district Detached: side and rear – 4 feet, front – determined by base zoning district, 5 feet from primary residence

Parking

JADUs: No parking required ADUs: One spot may be required (tandem allowed). No parking required if: ½ mile walking distance from public transit, in a historic district, or one block from a car-share vehicle on-street parking permits are required but not offered to ADU...

Owner occupancy

JADU: Required, deed restricted, ADU: Not required

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...