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ADU Contractors near San Mateo, CA
AKD Homes
3518 Arden Road, Hayward, CA 94545 12 milesAKD Homes is a SF Bay Area ADU contractor with 20+ years of experience. They offer full-service ADU design, permits, and construction, including detached ADUs, granny flats, and custom builds ranging from 400–750 sq. ft.
read moreDwelling Lab
21 El Caminito, Walnut Creek, CA 94598 28.2 milesDwelling Lab is an Oakland-based ADU design firm offering full-service planning, schematic design, construction drawings, permitting, and construction oversight for detached ADUs, attached additions, and garage conversions.
read moreAlameda Tiny Homes
2315 Lincoln Avenue, Alameda, CA 94501 15.3 milesNew Avenue, Inc
2120 University Avenue, Berkeley, CA 94704 22.2 milesNew Avenue, Inc is a full-service design-build company serving the San Francisco Bay Area and Portland, OR since 2011. They specialize in ADUs, custom homes, renovations, additions, and Enclaves, managing design, permitting, and construction under... read more
Atlas Construction
101 Jefferson Drive, Menlo Park, CA 94025 8.9 milesAtlas General Construction delivers complete ADU construction for detached, attached, and converted structures. Our team manages every phase of development including zoning research, architectural coordination, structural engineering, Title 24 com... read more
Burton Builders LLC
32 9th Street, Richmond, CA 94801 26.4 milesBurton Builders LLC is a trusted construction company specializing in ADU construction, single-family, multifamily, and commercial builds. Known for quality workmanship and client-focused service, they deliver expert results on every project.
read moreHome by Tom
1990 North California Boulevard, Walnut Creek, CA 94596 28 milesHome by Tom is a Bay Area ADU contractor with 21+ years of experience serving Walnut Creek. They build detached ADUs, attached ADUs, and garage conversions, managing design, permits, and construction for rental income or multi-generational living.... read more
Home WiP Construction Concierge
171 Main St 261, Los Altos, CA 16.1 miles9 Builders
San Jose, CA 95122 30.4 miles9 Builders is a Bay Area ADU contractor offering full-service design, permits & construction. Specializing in detached ADUs, garage conversions & additions, costs range $150K–$350K, taking 8–14 months to complete.
read moreAnura Design
367 Civic Drive, Pleasant Hill, CA 94523 32.1 milesAnura Design specializes in ADU design, offering styles from modern farmhouse and contemporary steel to Mediterranean stucco. Their interiors feature open-concept layouts, natural wood tones, and refined finishes tailored to compact, functional li... read more
Joy Line Homes
3110 Mission Drive, Capitola, CA 95065 37.2 milesJoy Line Homes offers the ADURA ADU Series — factory-built backyard cottages and granny flats featuring modern design, high-end finishes, and durable materials. An affordable, plan-based ADU solution for homeowners seeking quality detached acces... read more
Clarity Construction
111 North Market Street, San Jose, CA 95113 27.3 milesClarity Construction is a Bay Area contractor specializing in ADUs, home additions, and remodeling in Sunnyvale, Palo Alto, and South San Francisco. Services include backyard ADU builds, in-law suites, permits, and kitchen remodels.
read moreOCA Builders | Construction Company & ADU Contractor
245 20th Avenue, Santa Cruz, CA 95062 43.9 milesOCA Builders is a trusted Santa Cruz general contractor specializing in ADU construction, custom homes, kitchen & bathroom remodeling, room additions, and commercial build-outs, delivering quality craftsmanship with deep local zoning expertise... read more
Kyvos Construction
430 Railroad Avenue, Pittsburg, CA 94565 39.5 milesKyvos Construction offers home remodeling & ADU construction in Concord, CA. Services include kitchen & bathroom renovations, room additions, garage conversions, detached & attached ADUs, granny flats, and in-law suites.
read moreOther cities in California
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What you need to know
ADU Contractors in San Mateo: Building in One of the Bay Area's Most Sought-After Cities
San Mateo, California, sits at the heart of the San Francisco Peninsula, making it one of the most desirable — and expensive — housing markets in the nation. With median home prices consistently among the highest in the country, homeowners in San Mateo are increasingly turning to Accessory Dwelling Units (ADUs) as a smart way to add rental income, house family members, or increase property value. Finding experienced ADU contractors in San Mateo is the critical first step toward making this investment a reality.
San Mateo ADU Regulations and Permitting Requirements
San Mateo operates under both California state ADU law and its own local municipal code. The City of San Mateo has worked to align with state mandates that streamline ADU approvals, but there are still important local considerations every homeowner must understand before breaking ground:
- Maximum ADU size: Detached ADUs can be up to 1,200 square feet, while attached ADUs are generally limited to 50% of the primary dwelling's square footage.
- Setback requirements: A minimum 4-foot rear and side setback is typically required for new detached ADUs.
- Height limits: Detached ADUs are generally limited to 16 feet in height, though this can vary by zone.
- Owner-occupancy rules: California state law has suspended owner-occupancy requirements for ADUs through 2025, giving San Mateo homeowners more flexibility.
- Parking: In many cases, ADUs in San Mateo do not require additional parking spaces, especially when located near transit corridors.
Why You Need a Local ADU Contractor in San Mateo
Working with a licensed ADU contractor familiar with San Mateo's building department is essential. The city's permitting process involves plan checks, inspections, and compliance with the California Building Code, Title 24 energy standards, and local zoning ordinances. An experienced local contractor will know how to navigate the San Mateo Community Development Department, helping to avoid costly delays and revisions.
Types of ADUs Popular in San Mateo
Given the variety of lot sizes and home styles across San Mateo neighborhoods — from the flat streets near downtown to hillside properties in areas like Sugarloaf — ADU contractors in San Mateo commonly build several types of units:
- Detached ADUs: Standalone structures in the backyard, ideal for larger lots.
- Attached ADUs: Extensions of the existing home, sharing at least one wall.
- Garage Conversions: Transforming an existing garage into a livable unit, a popular and cost-effective option.
- Junior ADUs (JADUs): Units up to 500 square feet created within the existing home's footprint.
Choosing the Right ADU Contractor in San Mateo
When selecting an ADU contractor in San Mateo, CA, look for professionals who are licensed by the California Contractors State License Board (CSLB), carry proper insurance, and have a proven portfolio of completed ADU projects in the Bay Area. Request detailed bids, check references, and confirm familiarity with San Mateo's specific permitting timelines. A qualified contractor will guide you from design and permitting through construction and final inspection, ensuring your ADU is built safely, legally, and on budget.