Basement Conversion in California
Urbatect Development, LLC
7555 North Palm Avenue, Fresno, CA 93711
Urbatect Development LLC is a California & Washington ADU contractor offering custom homes, garage conversions, JADUs & detached ADUs. 15+ years experience, 3,500+ projects, fixed pricing & 30% faster permits.
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Elite ADU Santa Cruz
347 Soquel Avenue, Santa Cruz, CA 95062
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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Intelligent Choice Builders
1437 Park Avenue, San Jose, CA 95126
Intelligent Choice Builders is a licensed Bay Area ADU contractor serving Palo Alto, Cupertino, San Jose & Sunnyvale. They build detached ADUs, garage conversions, granny flats & more, managing permits, design & construction end-to-end.
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Joel & Co. Construction
11693 San Vicente Boulevard, Los Angeles, CA 90049
Joel & Co. Construction, serving Los Angeles since 1983, offers expert residential & commercial construction, including custom homes, kitchen & bathroom remodels, ADUs, room additions, and general contracting across Beverly Hills, Santa Monica & beyond.
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Golden State ADUs
6929 Sunrise Boulevard, Citrus Heights, CA 95610
Golden State ADUs is a full-service ADU contractor in Sacramento, CA. With 10+ years of experience and 100+ projects, they offer design, permitting, and construction for detached ADUs, in-law suites, and backyard cottages across California.
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ADU West Coast
13001 Seal Beach Boulevard, Seal Beach, CA 90740
ADU West Coast is a full-service ADU builder in Southern California specializing in garage conversions, detached units, granny flats & JADUs. 15+ years experience, full permitting support & flexible financing. Earn $1,900+/month in rental income.
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American Builders
1105 Grand Teton Drive, Pacifica, CA 94044
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 budget.
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Delcoi
21650 Oxnard Street, Woodland Hills, CA 91367
Delcoi is an ADU contractor specializing in granny flats, casitas, in-law suites, detached ADUs, garage conversions, and backyard cottages. They handle permits, regulatory compliance, and quality construction to maximize living space and rental income potential.
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Humboldt ADU
3015 H Street, Eureka, CA 95501
Humboldt ADU is a Humboldt County program helping homeowners build Accessory Dwelling Units (ADUs) like granny flats or backyard cottages to boost affordable housing. It offers guides on types, permits, financing, and construction.
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9 Builders
San Jose, CA 95122
9 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.
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ADU Gurus
450 South Melrose Drive, Vista, CA 92081
ADU Gurus™ is a California ADU builder since 2020, offering full-service design, permitting, and construction for granny flats, garage conversions, JADUs, and detached ADUs up to 1,200 sq ft on single-family and multi-family lots.
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Central Coast ADU
260 Maple Court, Ventura, CA 93003
Central Coast ADU offers full ADU planning, design, and permitting services for homeowners on the Central Coast. From granny flats to garage conversions, they deliver construction-ready plans and approved permits.
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ADU Builders Bay Area
111 N Market St Suite 1150, San Jose, CA 95113
ADU Builders Bay Area specializes in detached ADUs, garage conversions, in-law suites & more. Expert ADU contractors offering transparent pricing, full permitting & quality construction throughout the Bay Area.
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ADU Los Angeles
3744 Flower St, Los Angeles, CA 90007
ADU Los Angeles (ADLA) is a specialized ADU contractor serving LA County. They offer consulting, custom design, construction, garage conversions, basement ADUs, attached and detached units, helping homeowners maximize property value.
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Cornejos Builders
8909 Elmont Avenue, Downey, CA 90240
Cornejos Builders offers ADU construction, garage conversions & home additions in LA & Orange County. 24 ADUs completed in 4 years. Costs range $80K–$250K. Licensed, insured, bonded. 1-year warranty included.
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Other cities in California
What you need to know
Searching for top Basement Conversion ADU Contractors in California? Our directory highlights trusted local professionals who specialize in designing and building accessory dwelling units (ADUs).
Working with a qualified Basement Conversion ADU Contractor in California ensures your ADU project meets local building codes, zoning laws, and permit requirements. Whether you're planning a detached ADU, garage conversion, or backyard cottage, experienced Basement Conversion professionals can guide you through every step.
California homeowners are increasingly investing in ADUs to create additional living space, generate rental income, or support multigenerational living. The Basement Conversion experts featured here bring local expertise and proven experience to help make your project a success.
Browse our listings to find the best Basement Conversion ADU Contractors in California, and get started today.