Basement Conversion in California
ORO Coast Builders
7129 Forest Hills Road, Los Angeles, CA 91307
ORO Coast Builders is an ADU contractor in Los Angeles & the Bay Area with 25+ years of experience. They build detached ADUs, garage conversions, basement conversions & JADUs—fully custom, no prefab.
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Leon's Construction Inc.
3333 Vaca Valley Parkway, Poway, CA 95688
Leon's Construction Inc. offers ADU construction services in Escondido, Encinitas, and San Marcos, CA. They build backyard cottages, basement apartments, tiny homes, and more using durable, energy-efficient materials.
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Premium ADU
5161 Lankershim Boulevard, North Hollywood, CA 91601
Premium ADU is a Los Angeles ADU specialist offering design, permitting, and construction of detached ADUs, garage conversions, and JADUs. Operating since 2021 with an in-house team, projects typically complete in 6–12 months.
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Proteus Homes
793 North Avenue, Vista, CA 92083
Proteus Homes is a custom home and ADU builder with 30+ years of experience in the Southwest US. They offer full-service ADU construction, including design, permitting, and panelized off-site fabrication, with move-in-ready homes in under three months.
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Musick Construction Inc.
1818 Peacock Boulevard, Oceanside, CA 92056
Musick Construction Inc. offers ADU construction services including new builds and conversions like garage and basement conversions. They handle permits, design, and finishes for granny flats, in-law suites, and rental units.
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Backyard Unlimited
4765 Pacific Street, Rocklin, CA 95677
Backyard Unlimited, founded 2009 in Rocklin, CA, specializes in Amish-crafted sheds, gazebos, pergolas, and ADUs for Greater Sacramento homeowners. They handle full ADU design, permitting, and installation in-house, with no subcontractors.
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Cordeiro Custom Remodeling
1420 Main Street, Newman, CA 95360
Cordeiro Custom Remodeling offers expert ADU construction in Newman, Modesto & Turlock, CA. Services include garage conversions, detached ADUs, granny flats & in-law suites. 15+ years of residential remodeling experience.
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Hubbell & Hubbell Architects, Inc.
1970 Sixth Avenue, San Diego, CA 92101
Accessory Dwelling Units (ADUs) add value and flexibility to California properties. Learn about ADU regulations, design options like garage conversions, and how Hubbell & Hubbell Architects can help you build a compliant granny flat or guest house.
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Northbay Home Solutions
47 Paul Drive, San Rafael, CA 94903
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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BuildZig ADU Services
3007 Telegraph Avenue, Oakland, CA 94609
BuildZig ADU Services is a Bay Area ADU contractor specializing in design, permitting, and construction. They handle garage conversions, detached ADUs, basement/attic conversions, and more, offering transparent pricing throughout.
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ExpandADU | Prefab ADUs
41111 Mission Boulevard, Fremont, CA 94539
ExpandADU is a California-based prefab ADU builder offering full-service accessory dwelling unit construction, including consultation, design, planning, and build. Serving the Bay Area and beyond, they specialize in detached ADUs, granny flats, and JADUs.
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Alon Design & Remodeling
722 Charcot Avenue, San Jose, CA 95131
Alon Design & Remodeling is a leading ADU contractor offering detached, attached, garage conversion, basement, and JADU options. ADUs boost property value, generate rental income, and provide independent living spaces with full amenities.
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Golden State ADUs
930 G Street, Sacramento, CA 95814
Golden State ADUs is a Sacramento-based full-service ADU contractor offering design, permitting & construction. With 10+ years experience and 100+ projects, they build detached ADUs, in-law suites & backyard cottages across California.
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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.