Soliz General Construction & Painting Inc is a Bay Area ADU contractor with 20+ years of experience. They offer full-service ADU design and construction, including permits, structural work, and finishing for granny flats, in-law suites, and backyard cottages.
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ADBC Architecture completed an 800 SF detached ADU in East Bay, CA in 2025, designed for multigenerational living. Built with thermally modified wood and steel, the backyard cottage features high ceilings and large windows for a spacious feel.
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S.D White Construction Inc, a licensed Bay Area ADU contractor with 20+ years experience, builds detached, attached, garage conversion & above-garage ADUs in Richmond, CA. Full-service from design & permits to final inspection, completed in 3–5 months.
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DevArt8 Builders specializes in ADU construction in Gilroy, offering floor plans from 350–650 sq. ft. They handle permits, ensure zoning compliance, and build detached ADUs, attached units, and garage conversions tailored to each property.
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Greenberg Construction builds custom ADUs, including detached units & garage conversions. Services include 3D renderings, dedicated project management, eco-friendly options & expert design guidance to add value & living space to your property.
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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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Masterful Construction is a San Mateo ADU contractor serving the Bay Area. They build detached ADUs, garage conversions, and in-law suites, handling design, permits, and construction. Discounts available for military and first responders.
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Acton ADU is a Bay Area ADU contractor founded by Stan Acton with 30+ years of experience. They offer full-service ADU design, construction, garage conversions, and permitting across San Jose and the broader Bay Area.
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Done Right Builders & Remodeling is a licensed Bay Area ADU contractor (Lic#1002689) with 20+ years experience. Services include detached/attached ADUs, JADUs & garage conversions in Union City, Hayward, San Jose & Santa Clara.
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Green Bay Remodeling offers ADU construction in Palo Alto, CA, including detached units, garage conversions, basement units & JADUs. ADUs boost property value, generate rental income & support multigenerational living.
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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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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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Bay Builders & Remodeling specializes in custom ADU construction across Santa Clara, San Mateo, and East Bay. Services include attached, detached, garage conversions, and JADUs, helping homeowners add rental income, family housing, or workspace.
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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 fire-hazard restrictions, and the thoughtful planning needed to create homes that truly work for East Bay families.
read moreSan 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.