ADU Contractors in California
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 Positive energy designs.
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Revitalize Construction
209 Harding Boulevard, Roseville, CA 95678
Revitalize Construction (CA License #1099913) is a licensed general contractor in Sacramento offering residential & commercial construction, ADU builds, garage conversions, JADUs & renovations across Roseville, Folsom, Sacramento & surrounding Northern California communities.
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Ten Seventy Architecture
4411 30th Street, San Diego, CA 92116
Ten Seventy Architecture offers ADU design services in San Diego, led by Sean Canning. Specializing in detached ADUs, garage conversions & JADUs, they handle design to permitting. Costs start at $250–$300/sqft, with a $20K minimum design fee.
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MTZ Contractors
3515 Atlantic Avenue, Long Beach, CA 90807
Looking for the best ADU construction? Choose Mtz Contractors Inc to completely transform your property, known for constructing excellent ADUs in Long Beach CA. We create and build Accessory Dwelling Units that meet your precise requirements for quality.
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Supreme Remodeling Inc.
5000 Van Nuys Boulevard, Van Nuys, CA 91403
Supreme Remodeling Inc. is a licensed Los Angeles general contractor with 30+ years of experience. Services include kitchen & bathroom remodeling, ADU construction, garage conversions, room additions, and new home builds across LA, Ventura & Orange Counties.
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Humboldt ADU
3015 H Street, Eureka, CA 95501
Humboldt ADU is a Humboldt County program helping homeowners build Accessory Dwelling Units (ADUs) like granny flats or backyard cottages to boost affordable housing. It offers guides on types, permits, financing, and construction.
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San Gabriel Valley ADU
1841 South San Gabriel Boulevard, Rosemead, CA 91776
San Gabriel Valley ADU Construction Contractors build & convert ADUs, granny flats, garage conversions & in-law suites across Pasadena, Arcadia & nearby cities. Expert permitting, design & cost management for LA County homeowners.
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ENE Smarthome, Inc.
690 Saratoga Avenue, San Jose, CA 95129
ENE Smarthome, Inc. is a Bay Area contractor offering home remodeling, ADU construction, smart home upgrades, and accessibility improvements. Services include garage conversions, granny flats, aging-in-place remodels, and SB9-compliant ADU projects.
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ResCom ADU, LLC
675 Ygnacio Valley Rd B213, Walnut Creek, CA CA 94596
ResCom ADU is a full-service ADU builder in Walnut Creek, CA, offering design, permits, engineering, construction & hookups. With 100+ years of combined experience, they deliver custom, cost-effective accessory dwelling units using SIPs & Net-Zero technology.
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URBN BLDRS
4231 Balboa Ave, San Diego, CA 92117
URBN BLDRS is a specialized ADU contractor helping homeowners plan and build accessory dwelling units. They offer expert guidance, dedicated project teams, and streamlined processes from consultation to construction completion.
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ADU Ventura County
2734 Johnson Drive, Ventura, CA 93003
ADU Ventura County builds accessory dwelling units including detached ADUs, garage conversions, granny flats, and Casitas. With 10+ years of experience, they offer free consultations, budget estimates, and full construction management for Ventura County homeowners.
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亞華建築YAHUA CONSTRUCTION
650Bfremont Ave, Los Altos, CA 94024
YAHUA Construction Inc. is a California-based licensed general contractor with 20+ years of experience. Specializing in ADUs, remodeling, MEP, roofing, and more, they serve the Bay Area with quality, sustainable construction.
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Millan Construction, Inc
325 West Washington Street, San Diego, CA 92103
Millan Construction builds custom ADUs in San Diego, offering full-service design, permitting, and construction. With 14+ years of experience, they deliver compliant, high-quality accessory dwelling units that boost property value and rental income.
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ADU Design Build
21781 Ventura Blvd, Los Angeles, CA 91364
ADU Design + Build is a Los Angeles County general contractor specializing in ADU planning, design, and construction. Services include detached ADUs, garage conversions, and backyard cottages. ADUs can boost property value and generate $2,000+/month in rental income.
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ConstruBay
18 El Paseo Ln. Suite 18, Mill Valley, CA 94941
ConstruBay is a licensed ADU contractor in Marin County, CA, offering full design-build services across all 11 jurisdictions. Using AI tool PlanPass.ai, they achieve permits 40% faster. 150+ projects completed, 4.9-star Google rating.
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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.