ASL Remodeling is a California licensed ADU contractor (CSLB #1060310) with 20+ years experience and 300+ completed projects. Services include detached ADUs, garage conversions, granny flats, JADUs, and in-law suites with full design-build support... read more
Imagine the possibilities that a beautifully crafted ADU (accessory dwelling unit) brings to your Berkeley or Bay Area property. Whether it’s creating a cozy retreat for guests, a comfortable living space for family members, or an additional sou... read more
Regency Construction & Remodeling BA is a San Francisco ADU contractor offering new builds, space conversions, and prefab ADU solutions. They handle design to completion, manage permits, and ensure compliance with local zoning laws.
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OCA Builders offers ADU design & construction in Santa Cruz County, including detached, attached, garage conversion, internal & junior ADUs. They use county-approved floor plans to streamline permitting and reduce timelines.
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Custom ADU builders in Palo Alto, CA, specializing in granny flats, detached ADUs & backyard cottages. Personalized design, permitting, and full construction management for quality accessory dwelling units.
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Kaplan Architects added a 280 sq ft ADU to an existing garage in Crocker Highlands, Oakland. Built into a hillside, it features a kitchenette, full bath, and Tudor-style exterior, serving as office, studio, or rental unit.
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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
Deharo Construction is a trusted ADU builder serving Livermore, Pleasanton, and Dublin. Specializing in accessory dwelling units, new construction, and home additions, they deliver custom granny flats, detached ADUs, and in-law suites across the T... read more
Bay Harbor Remodeling & Construction is a licensed Bay Area contractor with 25+ years of experience. Services include kitchen & bathroom remodeling, ADU conversions, roofing, decks, and more across 50+ California cities.
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GR Innovative Builders Inc. is a Bay Area ADU contractor specializing in accessory dwelling units, granny flats, and in-law suites. Completed projects in Richmond, Oakland, Lafayette & Pinole. Featured in Sunset Magazine.
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Your Prefab ADU will be delivered and installed to your site. All ready to enjoy a sustainable home to last for generations.
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We are a family-first, boutique residential design & build firm serving the Orinda and East Bay community. We’re not just service providers — we’re your neighbors. We understand the local permitting process, the hillside terrain, the fir... read more
Edrington and Associates helps property owners add ADUs—garage conversions, detached units, or Junior ADUs. They offer ADU Feasibility Studies in three packages and a free 15-minute consultation to explore options.
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Northbay Home Solutions offers full-service ADU construction in San Rafael, San Francisco & North Bay. Services include detached ADUs, garage conversions & JADUs, covering design, permits & build.
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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
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 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:
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.
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:
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.