Optivest Build is a licensed general contractor offering ADU construction, garage conversions, home additions, renovations, and new builds. They manage permits, design, and inspections, delivering residential and commercial projects on time and wi... read more
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
Elite Construction builds ADUs in Santa Cruz County, offering detached units, garage conversions & addition ADUs. Projects range 250–1,200 sq ft, cost $115K–$450K, and take 6–9 months. Free estimates available.
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King David Construction is a Palo Alto ADU contractor offering full-service design, permitting & construction across the Bay Area. Specializing in detached ADUs, garage conversions & in-law suites.
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American Builders is a San Francisco ADU contractor specializing in garage conversions, detached units, in-law suites & basement conversions. They handle permits, zoning, and deliver code-compliant accessory dwelling units on time and on budge... read more
Dream Build Services is a full-service ADU contractor in Fremont, CA, offering detached ADUs, garage conversions, basement conversions, and JADUs. Services include design, permits, electrical, plumbing, HVAC, and solar integration across the East ... read more
ProStruct Engineering offers ADU structural engineering services across California, providing permit-ready plans and calculations for detached ADUs, garage conversions, granny flats, and more, with a 2–3 week turnaround.
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LiveLarge Home is a California prefab ADU builder offering full-service solutions from permits to final inspection. Build times start at 4–6 weeks, with fixed pricing from $412/sq. ft. Models range from studios to 2-bed/2-bath units with premium... read more
Remodeling Heroes is a licensed ADU contractor in the SF Bay Area offering garage conversions, detached ADUs, in-law suites, permits, and full project management for code-compliant, lot-smart accessory dwelling unit construction.
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ResCom ADU is a full-service ADU builder in Walnut Creek, CA, offering design, permits, engineering, construction & hookups. With 100+ years of combined experience, they deliver custom, cost-effective accessory dwelling units using SIPs & ... read more
Quality Choice Construction & Painting offers ADU construction services including studio, 1-bedroom, and 2-bedroom units. Options include garage conversions, backyard cottages, and detached ADUs for rental income or multi-generational living.<... read more
Tiny House Basics designs custom tiny house trailers with insulated floors, no thermal bridging, and build-ready delivery. Models range from 10–50ft, up to 12ft wide, in bumper pull or gooseneck styles. Lifetime consulting included.
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At Ingenuity Construction Group, we specialize in crafting exceptional Accessory Dwelling Units (ADUs) that blend seamlessly with your existing property. With over 20 years of experience, our dedicated team ensures each ADU project is completed wi... read more
HBC Construction, based in Fremont, CA, specializes in ADU building, garage conversions, new homes & additions across the Bay Area. Licensed, code-compliant, full-service from planning to completion.
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.