ADU Contractors near San Mateo, CA
Jeff Martinez Construction
11 Susie Ct, Oakley, CA 94561
45.6 miles
Jeff Martinez Construction Inc. builds ADUs in Oakley, CA with 27+ years of experience. Services include detached ADUs, garage conversions, permits, finishing, and landscape integration across Contra Costa County.
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Geico Builders
1901 Harrison Street, Oakland, CA 94612
17.8 miles
Geico Builders offers ADU services including detached ADUs, attached ADUs, Junior ADUs, garage conversions, and home additions. Ideal for rental income, family housing, or maximizing space on your existing property.
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Second Dwellings
100 Higgins Canyon Road, Half Moon Bay, CA 94019
9.1 miles
Edri Construction, Inc. San Francisco
701 Cortland Avenue, San Francisco, CA 94110
14.1 miles
Edri Construction, Inc. is a San Francisco-based ADU contractor offering full-service accessory dwelling unit construction across the Bay Area, including garage conversions, detached ADUs, granny flats, and energy-efficient home additions with in-... read more
Home WiP Construction Concierge
171 Main St 261, Los Altos, CA
16.1 miles
亞華建築YAHUA CONSTRUCTION
650Bfremont Ave, Los Altos, CA 94024
16 miles
YAHUA Construction Inc. is a California-based licensed general contractor with 20+ years of experience. Specializing in ADUs, remodeling, MEP, roofing, and more, they serve the Bay Area with quality, sustainable construction.
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ADU For You
1755 East Bayshore Road, Redwood City, CA 94063
7.1 miles
ADU For You is a Bay Area ADU builder based in Redwood City, offering end-to-end services including design, permits, and construction. Serving 1,000+ clients, they specialize in custom detached ADUs, granny flats, and in-law suites at competitive ... read more
Larson Shores Architects
1295 Alabama Street, San Francisco, CA 94110
16.6 miles
Larson Shores Architects is a San Francisco-based firm offering residential, ADU, and commercial design services. Founded in 2007 by Josh Larson, they specialize in new builds, garage conversions, in-law suites, and full permit navigation across t... read more
Barzel Builders
4039 Transport Street, Palo Alto, CA 94303
14.6 miles
AKD Homes
3518 Arden Rd, Hayward, CA 94545
12 miles
AKD Homes is a Bay Area ADU contractor with 20+ years of experience. They offer full-service ADU design and build, including detached ADUs, custom designs, and conversions from Berkeley to San Jose.
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Feldman Construction
3392 Georgetown Place, Santa Clara, CA 95051
22 miles
Feldman Construction specializes in custom ADU design and construction across the Bay Area, including San Mateo and Santa Clara County. They build detached ADUs, granny flats, and in-law suites to boost property value and expand living space.
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Bobcat Builders
East Palo Alto, CA 94303
10.9 miles
Bobcat Builders is a Bay Area ADU contractor specializing in accessory dwelling units in Palo Alto. They offer attached & detached ADUs, garage conversions, granny flats & in-law suites, backed by a Two Year Satisfaction Guarantee.
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Joy Line Homes
3110 Mission Drive, Capitola, CA 95065
37.2 miles
Joy 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
Nestadu
100 Shoreline Highway, Mill Valley, CA 94941
25.2 miles
Nestadu is a full-service ADU builder offering custom site-built and prefab accessory dwelling units. Prefab models range from $115K–$317K. Custom builds start at $400/sq ft. Financing options include HELOCs, construction loans, and CA grants.read more
Atra Construction
San Jose, CA 95120
33.9 miles
Atra Construction is a Bay Area ADU contractor offering full-service design and build. They handle permits, planning, and construction management. Floor plans range from 240 sq ft studios to 1,200 sq ft three-bedroom units.
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Other cities in California
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.