16 Best ADU Builders in San Mateo, California
Verified ADU contractors and builders in San Mateo, CA
Showing 1–16 of 16 listings
ADU San Mateo
We specialize in designing and building accessory dwelling units for San Mateo homeowners, helping you maximize your property's potential with expert construction from start to finish. Our ADU expertise covers everything from permits and planning to final installation, ensuring your project meets local building codes and your vision.
AGH Commercial Inc.
CALIBUILDER
Ecostar Remodeling & Construction
Front Street Builders - Home Remodeling San Mateo CA
Heavywood Construction
jesse ososki art, inc.
Lemon Remodeling and Services
Masterful Construction - Design & Build
Method Remodeling General Contractor
PremierGarage of the Bay Area
Regan's Renovations
San Mateo Remodeling Contractors
Sigura Construction, Inc.
Spaces Home Remodeling
Wilkinson Construction Inc
Frequently Asked Questions — ADU Builders in San Mateo
How much does it cost to hire an ADU builder in San Mateo?
ADU construction costs in San Mateo, California vary widely depending on size, type, and site conditions. Detached ADUs typically range from $150,000–$400,000+, while garage conversions and attached ADUs can be more affordable. Contact multiple builders in San Mateo to get accurate quotes for your specific project.
How long does it take to build an ADU in San Mateo?
In San Mateo, the ADU construction timeline typically ranges from 6 to 18 months from permit application to move-in. Permitting alone can take 2–6 months depending on California local regulations. Prefab and modular ADUs often have faster timelines than site-built units.
Do I need a permit to build an ADU in San Mateo?
Yes, a building permit is required for ADU construction in San Mateo, California. Your ADU builder will typically handle the permit application as part of their service. California has adopted streamlined ADU permitting laws in recent years, which may reduce wait times.
What types of ADUs can be built in San Mateo?
Common ADU types in San Mateo include detached ADUs (backyard cottages), attached ADUs, garage conversions, basement conversions, and prefab/modular ADUs. The best type for your property depends on lot size, zoning, and budget. A local San Mateo ADU builder can advise on what's allowed on your specific parcel.