Building Permits in San Mateo County, CA

Check permit requirements for home improvement projects in San Mateo County. Select a project type below to see local requirements, estimated fees, and how to apply.

37 Permit Rules
28 Project Types
IRC 2025 CRC Building Code

Key Exemptions in San Mateo County

These projects typically don't require a building permit in San Mateo County:

94037), fences 6 feet or less are typically exempt from a building permit per 2025 CRC R105.2. Midcoast LCP view-corridor rules may restrict fence placement or material on parcels with designated ocean or ridgeline views; check with SMC Planning if your parcel is in a view corridor. Fences over 6 feet within the Coastal Zone may trigger CDP review even without a building permit.

94037), minor roof repairs that do not involve sheathing replacement are typically exempt. Once the scope grows beyond one slope or changes the cover system, pull the full re-roof permit — and be aware that in VHFHSZ, Class A roofing is required.

94037), replacing a window or exterior door in the existing rough opening is typically exempt from a building permit. Title 24 Part 6 U-factor and SHGC compliance applies to replacement windows. Egress rules per 2025 CRC R310 apply to bedroom windows. VHFHSZ parcels require WUI-rated (tempered, multi-pane) glazing per Chapter 7A.

See all rules by selecting a project type below, or use our free lookup tool for a personalized answer.

Deck
2 rules
Fence
2 rules
Shed
2 rules
Roof Replacement
2 rules
Windows and Doors
2 rules
Bathroom Remodel
1 rule
Kitchen Remodel
1 rule
Swimming Pool, Hot Tub, or Spa
2 rules
Electrical Work
1 rule
Plumbing Work
1 rule
HVAC
1 rule
Garage
2 rules
Room Addition
1 rule
Basement Finishing
1 rule
Retaining Wall
2 rules
Solar Panels
1 rule
Patio
1 rule
ADU
1 rule
Driveway
1 rule
Demolition
1 rule
EV Charger
1 rule
Generator
1 rule
Gas Line
1 rule
Water Heater
2 rules
Tree Removal
1 rule
Siding
1 rule
Fireplace
1 rule
Concrete Slab
1 rule

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San Mateo County Building Department

NameSan Mateo County Planning and Building Department
Phone(650) 599-7310
Emailbuildinginspections@smcgov.org
WebsiteVisit website
Address455 County Center, 2nd Floor, Redwood City, CA 94063
HoursMonday-Thursday 8:00 AM - 4:00 PM (closed noon-1 PM); closed Friday-Sunday

Nearby Cities in California

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Permit Guides

Read our in-depth guides for common home improvement projects:

Deck Guide Fence Guide Shed Guide Roof Guide Window & Door Guide Bathroom Guide Kitchen Guide Pool Guide Electrical Guide Plumbing Guide HVAC Guide Garage Guide Addition Guide Basement Guide Retaining Wall Guide Solar Guide Patio Guide ADU Guide Driveway Guide Demolition Guide EV Charger Guide Generator Guide Gas Line Guide Water Heater Guide Tree Removal Guide Siding Guide Fireplace Guide Concrete Slab Guide
Disclaimer: Always confirm with your local building department before starting your project. PermitMint provides general guidance, not legal advice.