ADU Contractors in California
Quartz Construction
1777 Hamilton Avenue, San Jose, CA 95125
Quartz Construction builds ADUs in San Jose, including detached units, garage conversions, and in-law suites. ADUs offer extra space, passive rental income, and multigenerational living solutions for Bay Area homeowners.
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Level House Construction Inc
17332 Keaton Ave, Sonoma, CA 95476
Level House Construction Inc. builds ADUs in Marin & Sonoma County, CA. Specializing in granny flats, in-law units & backyard cottages, they help homeowners add rental income, family housing & extra living space while boosting property... read more
Pasadena Master ADU Builder
930 East Colorado Boulevard, Pasadena, CA 91106
Pasadena Master ADU Builder is a top ADU contractor in San Gabriel Valley, offering detached ADUs, garage conversions, and JADUs. With 20+ years experience, 150+ projects, and 98% satisfaction, they deliver compliant, high-quality builds boosting ... read more
Accuracy Remodeling LLC
3144 G Street, Merced, CA 95340
Accuracy Remodeling LLC, serving Merced, CA since 2013, offers new construction, remodeling, and ADU contracting for residential and commercial clients. Licensed, insured, and free estimates available.
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Morrison Construction
601 Carmen Dr, #215D, Camarillo, CA 93010
Morrison Construction offers expert ADU building services in West Hills, handling everything from planning to completion. Services include custom design, construction, plumbing, electrical, and interior finishes for granny flats, rental units, and... read more
LRL Builders, Inc.
1661 Botelho Drive, Walnut Creek, CA 94596
LRL Builders, Inc. is a licensed ADU contractor in Walnut Creek, CA, specializing in detached, attached, garage conversion, and junior ADUs. They handle design, permitting, and construction, serving Walnut Creek and surrounding Bay Area communitie... read more
Hilario Construction
Santa Rosa, CA 95405
Hilario Construction is a Santa Rosa ADU contractor offering full-service accessory dwelling unit construction, including permits, design, and turnkey delivery. Serving Santa Rosa, Windsor, and Petaluma, they build detached ADUs, granny flats, and... read more
Bao-Tran Builders Inc
2156 The Alameda, San Jose, CA 95126
Bao-Tran Builders Inc specializes in ADU construction, including detached ADUs, granny flats, JADUs, garage conversions & multi-unit properties. Expert ADU contractor delivering functional, high-quality housing solutions for property owners.read more
Custom Home Builders Malibu
42400 Winchester Road, Temecula, CA 92590
Custom Home Builders Malibu specializes in ADU construction, backyard Casitas & granny flats. They offer turnkey design-build services, handling permits & compliance with California ADU laws for legal, independent living spaces.
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Atra Construction
San Jose, CA 95120
Atra Construction is a Bay Area ADU contractor offering full-service design and build. They handle permits, planning, and construction management. Floor plans range from 240 sq ft studios to 1,200 sq ft three-bedroom units.
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Bay Villa Builders
36007 Bayonne Drive, Newark, CA 94560
Bay Villa Builders brings over 50 years of combined experience in crafting expertly designed ADUs that enhance both your home's functionality and its value. An Accessory Dwelling Unit, or ADU, serves as an additional living space on your property.... read more
Cairn Collaborative
863 Pacific Street, San Luis Obispo, CA 93401
Cairn Collaborative designed a 1,000 sq ft Passive House ADU in San Luis Obispo. This fossil-fuel-free, 3-bed/2-bath unit features airtight construction, heat pumps, HRV system, and thermally broken windows for minimal energy costs and long-term p... read more
Greenberg Construction
908 Industrial Avenue, Palo Alto, CA 94303
Greenberg Construction builds custom ADUs, including detached units & garage conversions. Services include 3D renderings, dedicated project management, eco-friendly options & expert design guidance to add value & living space to your p... read more
The ADU Group
16000 Ventura Boulevard, Encino, CA 91436
Los Angeles ADU builders with 10+ years experience, 220+ completed projects & 98% client satisfaction. Full-service ADU construction, garage conversions, design, permits & a deferred payment program—no payments until your ADU is rental-r... read more
United State Of The Art Construction
18034 Ventura Boulevard, Encino, CA 91316
Licensed LA construction firm United State Of The Art Construction specializes in ADU building and luxury home renovations across Brentwood, Beverly Hills & Malibu. Offering eco-friendly builds, full remodels & free consultations.
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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.