Basement Conversion in California
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, an... read more
SJB Construction Inc
9739 Deer Hollow Court, Santee, CA 92071
Building a granny flat (ADU) in San Diego can boost property value and ease housing needs. Detached ADUs up to 1,200 sq ft start at $250/sq ft. Fee waivers may save homeowners $14,000+. Rules apply regarding zoning, lot use, and size limits.
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A1 Building Contractors LLC
6885 Douglas Blvd, Granite Bay, CA 95746
Sacramento ADU Builder — Granite Bay & Roseville
Veteran-Owned Sacramento ADU Builders · Detached ADUs, Garage Conversions & Additions
Sacramento ADU Builders — 20+ Years, CSLB Licensed
A1 is a CSLB-licensed Sacramen... read more
Edrington and Associates
5944 Claremont Avenue, Oakland, CA 94618
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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Adapt Dwellings
5944 Claremont Avenue, Oakland, CA 94618
ADUs add rental income & property value. Services include garage conversions, detached ADUs, JADUs & granny flats. ADU Feasibility Studies cover code, utilities & ROI. Architectural services via Adapt Dwellings ensure smooth approval t... read more
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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EHD Builders
18375 Ventura Boulevard, Tarzana, CA 91356
EHD Builders offers ADU construction services in Los Angeles, CA, including garage conversions, detached units & additions. Costs range from $150K–$350K+. Services cover permits, framing, plumbing, electrical & more.
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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 mo... read more
West Coast Building and Design
9511 Nicole Way, Santee, CA 92071
West Coast Building and Design builds ADUs in California, including granny flats, garage conversions, and detached units. They help homeowners boost property value, house family members, or earn rental income through structured, process-driven con... read more
LA ADU Solutions Inc.
Los Angeles, CA 90012
Accessory Dwelling Units (ADUs) offer California property owners passive income, elderly care solutions, and property value growth. Since 2020 legislation, ADU permits are easier to obtain. Construction costs range $350–$450/sq ft, with rental i... read more
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 budge... read more
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 h... read more
Green Design and Build
16120 Sherman Way, Van Nuys, CA 91406
Licensed, veteran-owned ADU builder in Van Nuys. Detached, attached and junior ADUs plus garage conversions, with design, permits and construction handled under one roof.
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Jay Remodeling
15219 Sunset Boulevard, Los Angeles, CA 90272
Jay Remodeling is a licensed ADU contractor in Los Angeles offering attached, detached, garage conversion, basement, and Junior ADUs. They handle design, permitting, and construction, helping homeowners add rental income or family space while boos... read more
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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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.