ADU Contractors in California
Doran Construction
1041 N Cypress St, La Habra, CA 90631
At Doran Companies LLC, we specialize in creating accessory dwelling units (ADUs) that are not just spaces, but extensions of your home’s character. Whether you’re considering garage conversions, new construction, or in-law suites, our expertise ensures a seamless blend of functionality and aesthetics.
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ADU Custom Home Source
1420 East Katella Avenue, Norco, CA 92867
ADU Custom Home Source, based in Riverside, CA, specializes in custom manufactured homes and ADUs. Serving Southern California, they handle design, permitting, financing, and installation, offering granny flats, casitas, and detached ADUs.
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Edri Construction, Inc. Mill Valley
1 Belvedere Pl, Mill Valley, CA 94941
Edri Construction, Inc. is a Mill Valley-based Bay Area ADU contractor offering full-service accessory dwelling unit construction, including garage conversions, detached ADUs, JADUs, and in-law suites, with permit handling and energy-efficient building.
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Apex ADU Builders
10050 North Foothill Boulevard, Los Angeles, CA 95014
Apex ADU Builders is a Los Angeles-based contractor specializing in accessory dwelling unit construction. Services include new builds, garage conversions, permitting, and design. Costs range from $80K–$400K, with potential ROI 35% higher than homes without ADUs.
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ProStruct Engineering
450 Folsom Street, #1502, San Francisco, CA 94105
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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Fullerton ADU Builder
125 North Euclid Street, Fullerton, CA 92832
Fullerton ADU Builder offers expert ADU construction services including detached ADUs, garage conversions, JADUs, in-law suites & home additions. 10+ years experience, licensed & insured, transparent pricing, free consultations & full permit handling.
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Samara
2840 Bay Road, Redwood City, CA 94063
Samara's Backyard ADU offers prefab accessory dwelling units for California homeowners. Five sizes available, including the 950 sq ft XL 10. Factory-built, fire-resistant, energy-efficient, with full-service permitting, installation & flexible financing.
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Martins Construction Corp
1666 Courtney Ave., Los Angeles, CA 90046
California's 2020 ADU laws allow two ADUs on single-family lots, reduced setbacks, larger units up to 800 sq ft, no owner-occupancy rules until 2025, faster approvals, and expanded parking exemptions statewide.
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ADU Custom Homes
1420 East Katella Avenue, Orange, CA 92867
ADU Custom Homes is a licensed California ADU contractor with 35+ years of experience serving LA, Orange & Riverside counties. They specialize in detached ADUs, garage conversions & additions, managing projects from permits to Certificate of Occupancy.
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First Choice Home Builders
10620 Treena Street, San Diego, CA 92131
First Choice Home Builders is a licensed San Diego ADU contractor with 15+ years of experience. They offer full-service ADU construction, including detached ADUs, garage conversions, and JADUs, with permit handling and flexible financing options.
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ESV Prime Construction Specialists
3330 Barham Boulevard, Sherman Oaks, CA 90068
ESV Prime Construction Specialists offers full-service residential construction in Los Angeles, including kitchen & bathroom remodeling, ADU construction, custom home builds, green building, architectural design, and interior & exterior painting.
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Pure Energy Construction
9301 Corbin Avenue, Northridge, CA 91324
Pure Energy Construction (License #1066309) is a Northridge, CA general contractor serving Southern California. They specialize in kitchen remodels, bathroom renovations, and ADU construction, including garage conversions and detached units.
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ADU Construction OC
San Clemente, CA 92705
ADU Construction OC specializes in accessory dwelling units in San Clemente, CA. Services include detached ADUs, garage conversions, above-garage ADUs & JADUs. Founded by Jed Stamen with 30+ years experience.
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Gannage Construction
1560 Santa Rita Road, Templeton, CA 93465
At Gannage Design & Construction, we specialize in ADU construction on the Central Coast, guiding you from concept to completion with a seamless, stress-free process.
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Custom ADU Builder
Los Angeles, CA 90012
Custom ADU Builder specializes in detached ADUs, attached ADUs, garage conversions & JADUs. Projects complete in ~3 months. Pricing starts at $235/sqft. Turn-key builds include quartz countertops, tile showers & luxury vinyl flooring.
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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.