ADU Contractors in California
UNI Construction
1142 South Diamond Bar Boulevard, Diamond Bar, CA 91765
UNI Construction builds detached and attached ADUs, handling site planning, structural engineering, and permit-ready drawings. Options include backyard cottages, granny flats, and in-law suites, all code-compliant and tailored to your property.
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Bunch Design
2718 West Avenue 34, Los Angeles, CA 90065
ADUs (granny flats/backyard cottages) boost property value & rental income. Bunch Design, LA, offers custom & pre-designed ADUs: Garage Studio ($300K+), Cottage ($400K+), Stop Making Sense ($425K+), and Step ADU ($425K+).
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8A-Concrete & Construction
Fresno St, Fresno, CA 93703
8A-Concrete & Construction builds ADUs, garage conversions, and room additions in Fresno, Clovis & Visalia. Services cover foundation, framing, electrical, plumbing & interior finishes. Projects managed from permit to final inspection.
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MHB Inc
214 Marina Lane, Waterford, CA 95386
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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SDS Homes
42400 Winchester Road, Temecula, CA 92590
SDS Homes Construction is a Temecula, CA design-build contractor specializing in ADUs, granny flats, and Casitas. They offer turnkey services from design to permitting and construction, serving Temecula and Murrieta homeowners.
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Lee & Co Contractors
251 Auburn Ravine Road, Sacramento, CA 95603
Lee & Co Contractors builds custom ADUs and home additions in Sacramento, Auburn, and Northern California. Services include detached ADUs, in-law suites, garage conversions, and home expansions, with a planning-first approach for smooth construction.
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Build ADU Home Remodel
4780 West Mission Boulevard, Montclair, CA 91762
Build ADU Home Remodel is a trusted, licensed general contractor serving homeowners throughout the Inland Empire with full-service ADU construction. Whether you're looking to add rental income, house extended family, or increase your property value, we build ADUs that meet your needs and exceed your expectations.
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Tate & Son, Inc.
8865 Calle Perico, San Diego, CA 92129
Tate & Son, Inc. is a licensed ADU contractor in San Diego & Southern California. They offer garage conversions, in-law suites & detached ADUs. Pricing starts ~$70K. 5-year warranty. Free estimates available.
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Granny Homes
16 Richards Drive, Roseville, CA 95678
Granny Homes, founded by Jason Lewis, is a Sacramento-based ADU contractor specializing in attached ADUs, detached backyard cottages, and garage conversions. They offer full-service design, permitting, and construction for functional, affordable accessory dwelling units.
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Edri Construction, Inc. San Francisco
701 Cortland Avenue, San Francisco, CA 94110
Edri Construction, Inc. is a San Francisco-based ADU contractor offering full-service accessory dwelling unit construction across the Bay Area, including garage conversions, detached ADUs, granny flats, and energy-efficient home additions with in-house project management.
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Resilient Homes Inc.
South Lake Tahoe, CA 96150
Resilient Homes Inc is a licensed ADU contractor offering custom accessory dwelling units, including granny flats, in-law suites, and rental units. They handle permitting, design, and construction with guaranteed workmanship and budget transparency.
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Next Level ADU Builders
8520 Florence Avenue, Downey, CA 90240
Next Level ADU Builders, serving Los Angeles, Riverside & Pico Rivera since 1997, specializes in ADU construction—detached units, granny flats & casitas—plus HVAC, remodeling & roofing, with financing options available.
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Bobcat Builders
East Palo Alto, CA 94303
Bobcat Builders is a Bay Area ADU contractor specializing in accessory dwelling units in Palo Alto. They offer attached & detached ADUs, garage conversions, granny flats & in-law suites, backed by a Two Year Satisfaction Guarantee.
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HardyBuilt Custom Construction Inc.
1151 Hayes Road, McKinleyville, CA 95519
HardyBuilt Custom Construction Inc. is a licensed General Contractor in Humboldt County, CA, specializing in custom homes, ADU builds, whole house remodels, additions, and kitchen & bathroom renovations built for Marine Climate Zone 4C.
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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.