ADU Contractors in California
Element Home Remodeling
800 West El Camino Real, Mountain View, CA 94040
Element Home Remodeling is a Mountain View ADU contractor offering full design-build services in Silicon Valley. They specialize in garage conversions, backyard cottages, in-law suites & rental units, serving Palo Alto, Sunnyvale & San Jose.
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Bayside Builders Group
1151 Harbor Bay Parkway, Alameda, CA 94502
Bayside Builders Group is a licensed Bay Area ADU contractor with 25+ years of experience. Services include detached ADUs, garage conversions, and in-law suites. Serving Oakland, San Jose, San Francisco, and surrounding counties.
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Edri Construction, Inc. Berkeley
2120 University Ave, Berkeley, CA 94704
Edri Construction, Inc. is a Berkeley-based general contractor specializing in ADU construction across the Bay Area. Services include garage conversions, detached ADUs, attached additions, granny flats, and custom interiors, with full project management from permits to finishing.
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Cabal Construction
7103 University Avenue, La Mesa, CA 91942
Detached ADUs (backyard cottages, granny flats) are standalone units adding rental income, family housing, or workspace. Costs range $100K–$350K. Cabal Construction guides homeowners through design, permits, and construction.
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ADUplus consulting
119 Fletcher Parkway, El Cajon, CA 92020
ADUplus Consulting Inc., trusted since 1979, offers full-service ADU design, permitting, and construction in California. From detached ADUs to garage conversions, they help homeowners boost property value and generate rental income.
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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.
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Get Bizzy LLC
150 Riverbank Lane, Heritage Ranch, CA 93446
Get Bizzy LLC specializes in garage-to-ADU conversions in San Luis Obispo County. They handle permits, design, construction & inspections for 1, 2 & 3-car garages, creating fully legal, California-compliant accessory dwelling units.
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Dwelling Lab
21 El Caminito, Walnut Creek, CA 94598
Dwelling Lab is an Oakland-based ADU design firm offering full-service planning, schematic design, construction drawings, permitting, and construction oversight for detached ADUs, attached additions, and garage conversions.
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My Space Remodeling Inc.
24313 Main Street, Newhall, CA 91321
My Space Remodeling Inc. is a licensed ADU contractor in Westlake Village, CA, specializing in ADU design, construction, and garage conversions. They offer free estimates, financing, and hold an A+ BBB rating.
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Peck General Construction
18734 Lilac Street, Hesperia, CA 92345
Peck General Construction builds ADUs in Orange County, Los Angeles & Inland Empire. Services include garage conversions, detached backyard cottages & granny flats. Full-service from permits to final inspection under a Design-Build model.
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Angelus Construction
330 Arden Avenue, Glendale, CA 91203
Angelus Construction is a Los Angeles ADU contractor with 30+ years of experience. They offer full-service ADU design, permitting, and construction, plus residential remodeling across Los Angeles and Ventura Counties.
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OneStop ADU
2667 Camino del Rio South, San Diego, CA 92108
OneStop ADU is a San Diego County ADU contractor with 25+ years of experience. They offer custom-built detached ADUs from ~$335/sq ft, including solar, permits & plans. Free feasibility studies available. ADA-compliant units offered.
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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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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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RL Remodeling
4360 Twain Avenue, San Diego, CA 92120
RL Remodeling offers garage conversions, room additions, and ADU construction. With nearly 50 years of combined experience, they handle design, permits, and execution. Garage ADU conversions typically cost $30K–$60K+, offering strong rental income potential and increased property value.
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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.