ADU Contractors in California
ADU For You
1755 East Bayshore Road, Redwood City, CA 94063
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 prices.
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Cloud9 Construction
7770 East McKinley Avenue, Clovis, CA 93737
Cloud9 Construction is a custom ADU builder specializing in accessory dwelling units, granny flats, in-law suites, and backyard cottages. They offer tailored design and construction services, helping homeowners maximize property value and space.
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Concept Renovations Inc.
16001 Ventura Boulevard, Encino, CA 91436
Concept Renovations Inc. is a Southern California design-build company with 20+ years in residential remodeling, ADU construction, and garage conversions. They manage design, permitting, and build phases, serving Los Angeles homeowners.
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PacGen Construction
29995 Technology Drive, Murrieta, CA 92563
PacGen Construction is a Temecula-based ADU contractor specializing in granny flats, casitas, and in-law suites. They offer full design-build services, permitting assistance, and custom ADU construction for homeowners seeking rental income or extra living space.
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Quality Choice Construction & Painting
900 Doolittle Drive, Oakland, CA 94577
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.
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WD-4D Builders
121 West Ridgecrest Boulevard, Ridgecrest, CA 93555
WD-4D Builders specializes in ADU construction and garage conversions across California. Services include detached ADUs, granny flats, casitas, and garage-to-living-space conversions, covering design, permitting, and build from start to finish.
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Homes by Hedges
PO Box 2586, Valley Center, CA 92082
Homes by Hedges is an experienced ADU contractor in North San Diego County, building granny flats, casitas & garage conversions. Serving Valley Center, Escondido & more for 25+ years, managing permits & local zoning regulations.
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Zacarias Remodeling Construction Inc.
1320 Paso de sauce Rd. Ste 600, Concord, CA 94520
Zacarias Remodeling Construction Inc. builds custom ADUs in the Bay Area, including garage conversions, detached ADUs, and in-law suites. They handle permits, design, and construction, helping property owners add rental income or multigenerational living space.
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Avica Construction & Development Inc
357 West Route 66, Glendora, CA 91740
Avica Construction & Development Inc is a licensed LA-based ADU contractor building detached ADUs, garage conversions, attached ADUs & JADUs across Los Angeles, Orange County & San Bernardino County, managing design, permits & construction.
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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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MHP Construction
2402 South Sergeant Avenue, Rancho Cordova, CA 64804
MHP Construction offers ADU construction services in California, including detached units, conversions, and in-law suites. ADUs provide rental income, family housing, and flexible living—without buying extra land.
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Rosegold Builders, Inc.
358 South Abbott Avenue, Milpitas, CA 95035
Rosegold Builders builds custom ADUs across the Bay Area and Los Angeles, handling permits, zoning, and construction. Services include garage conversions, backyard cottages, and rental units designed to boost property value.
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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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KGM Construction
1508 Mill Street, San Luis Obispo, CA 93401
Founded in 1986 by Mike Morain, KGM Construction is an A+ BBB-rated contractor offering residential remodeling, new home construction, ADUs, granny flats, garage conversions, commercial builds, and storm damage restoration with 35+ years of experience.
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Alto Builders
5450 Lake Lindero Dr., Agoura Hills, CA 91301
Alto Builders specializes in ADU construction in Los Angeles & Ventura County. Services include detached ADUs, garage conversions & JADUs. Costs range $300–$600/sq ft, with timelines of 5–12 months.
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Other cities in California
What you need to know
ADU Contractors in California: Navigating the Golden State's Unique Landscape
California is at the forefront of the Accessory Dwelling Unit (ADU) movement in the United States. With one of the most severe housing shortages in the nation, the state has enacted sweeping legislation to make ADU construction more accessible. Since 2020, California laws such as AB 68, AB 881, and SB 13 have significantly reduced barriers, eliminating minimum lot size requirements, reducing setback rules, and streamlining the permitting process. For homeowners looking to add value to their property or create additional rental income, working with experienced ADU contractors in California has never been more important.
What California ADU Contractors Must Know About State Regulations
Professional ADU contractors operating in California must stay current with a constantly evolving regulatory environment. Under California law, local agencies are required to approve or deny ADU permit applications within 60 days. Additionally, ADUs under 800 square feet cannot be denied solely based on floor area ratio limits. Contractors must also be familiar with owner-occupancy rules, utility connection requirements, and fire safety standards that vary by county and municipality. Cities like Los Angeles, San Diego, and San Jose each have their own local ordinances layered on top of state law, making local expertise a critical asset.
Types of ADUs Built by California Contractors
Experienced California ADU contractors are skilled in building a wide variety of ADU types to suit different property configurations and homeowner needs. The most common types include:
- Detached ADUs: Standalone structures built in the backyard or side yard of a primary residence.
- Attached ADUs: Units that share a wall with the main home, often built as additions.
- Garage Conversions: Transforming existing garages into livable spaces, a popular and cost-effective option.
- Junior ADUs (JADUs): Units up to 500 square feet created within the existing footprint of a home.
How to Choose the Right ADU Contractor in California
Selecting the right contractor is one of the most critical decisions in any ADU project. Homeowners should look for contractors who hold a valid California Contractors State License Board (CSLB) license, ideally a Class B General Building Contractor license. It is also important to verify that the contractor carries proper liability insurance and workers' compensation coverage. Look for professionals with a proven track record of successfully permitted ADU projects in your specific city or county.
The Benefits of Building an ADU in California
Building an ADU in California offers significant financial and lifestyle benefits. Homeowners can generate rental income to offset mortgage costs, house family members, or increase overall property value. In high-cost markets like the San Francisco Bay Area or Los Angeles, a well-built ADU can add hundreds of thousands of dollars in property value. With the right California ADU contractor by your side, the process can be smooth, compliant, and highly rewarding.