ADU Contractors in California
Top Rated Builders
5450 Thornwood Drive, San Jose, CA 95123
At Top Rated Builders, we offer expert ADU construction services tailored to meet your specific needs. Whether you’re looking to add a studio ADU, a one-bedroom ADU, or a larger family unit, our experienced team will guide you through the entire... read more
MGMW Remodeling
11041 Santa Monica Blvd #301, Los Angeles, CA 90025
MGMW Remodeling INC is a Los Angeles ADU contractor specializing in accessory dwelling units. Services include detached ADU construction, garage conversions, architectural design, permitting, and full project management from planning to completion... read more
MyADU4Less
579 West County Line Road, Calimesa, CA 92320
MyADU4Less is a Southern California ADU builder specializing in prefabricated accessory dwelling units. Offering models from 160–1,200 sq ft, they handle design, permitting, and construction. CalHFA grants up to $40,000 may apply.
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Roof and Realm
2245 Vía De Mercados, Concord, CA 94520
Roof and Realm is a California-based steel-framed modular home and ADU builder offering fire, earthquake, and wind-resistant structures. Their eco-friendly builds use 98% recyclable materials, generate minimal waste, and support solar-ready, Net P... read more
prefabADU
1111 Western St, Fairfield, CA CA 94533
prefabADU is a Bay Area ADU builder with 16+ years of experience offering affordable kits and plans from under $45K. With 12 state-approved plans valid across California, they simplify permits, design, and installation for homeowners.
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American Helical
1850 Countryside Dr. #1005, Turlock, CA 95380
American Helical (CA LIC #1128975) is a full-service ADU contractor in California offering planning, design, permitting, and construction. A 3rd-generation builder, they provide pre-designed models, custom ADUs, and prefab installs across multiple... read more
Central Coast Project Planning
1204 Kapareil Ln., Paso Robles, CA 93446
CCPP helps homeowners plan & permit ADUs in San Luis Obispo County. Options include custom, stock plan, or manufactured units. Permitting takes 4–12 months, with costs ranging from $40K–$70K depending on ADU type.
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Cornejos Builders
8909 Elmont Avenue, Downey, CA 90240
Cornejos Builders offers ADU construction, garage conversions & home additions in LA & Orange County. 24 ADUs completed in 4 years. Costs range $80K–$250K. Licensed, insured, bonded. 1-year warranty included.
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S Squared Construction & Pool Contractor
3343 Bancroft Drive, Spring Valley, CA 91977
S Squared Construction & Pool Contractor is a licensed Solana Beach, San Diego contractor with 13+ years of experience in ADU construction, garage conversions, and custom pool installation. They handle design, permitting, and building for deta... read more
Colibri Kitchen & Bath
5976 Telegraph Ave, Oakland, CA 94609
Colibri Kitchen & Bath offers full-service ADU construction in Oakland, handling design, permitting, and building. Services include site assessment, architectural plans, 3D renderings, and complete construction from foundation to finishing.read more
Full Steam Ahead Construction
3527 Mount Diablo Boulevard, Lafayette, CA 94549
Licensed ADU contractor Full Steam Ahead Construction serves East Bay homeowners with custom accessory dwelling units, including garage conversions, backyard cottages & in-law suites. Serving Concord, Oakland, Berkeley & more.
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Lux Builders
1020 Manhattan Beach Boulevard, Manhattan Beach, CA 90266
Lux Builders offers room additions & ADU services in Los Angeles, including detached ADUs, garage conversions & second-story additions. With 20+ years experience, they manage design, permits & construction across LA County.
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Buildwright Construction
5320 Satsuma Avenue, North Hollywood, CA 91601
Buildwright Construction offers full-service ADU construction, including detached ADUs, granny flats, in-law suites, and JADUs. They handle planning, permits, and building, helping property owners add rental income, guest space, or multi-generatio... read more
The Los Angeles ADU Builders
240 South Beverly Drive, Beverly Hills, CA 90212
Los Angeles ADU Builders is a licensed ADU contractor in Beverly Hills offering custom ADU design, garage conversions, detached ADUs, JADUs & in-law suites. CSLB certified, fully insured, with expert permit handling & transparent pricing.<... read more
Newform Builders
10960 Wilshire Boulevard, Los Angeles, CA 90024
Newform Builders specializes in ADU construction for multi-family and mixed-use properties. They handle permits, inspections, and code-compliant builds, including detached, attached, and space-conversion ADUs, ensuring safe, regulation-aligned res... read more
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.