Alto Builders specializes in ADU construction in Los Angeles & Ventura County. Services include detached ADUs, garage conversions & JADUs. Costs range $300–$600/sq ft, with timelines of 5–12 months.
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More Concrete Inc. is a licensed, bonded ADU contractor in San Diego specializing in concrete foundations for detached ADUs, in-law suites, and home offices, helping homeowners expand living space and increase property value.
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Gary Faith Construction is a licensed ADU contractor in San Diego specializing in detached ADUs, garage conversions, and above-garage units. Serving San Diego County, they manage projects from consultation to completion, ensuring full compliance with local zoning laws.
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Kyvos Construction offers home remodeling & ADU construction in Concord, CA. Services include kitchen & bathroom renovations, room additions, garage conversions, detached & attached ADUs, granny flats, and in-law suites.
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LiveLarge Home is a California prefab ADU builder offering full-service solutions from permits to final inspection. Build times start at 4–6 weeks, with fixed pricing from $412/sq. ft. Models range from studios to 2-bed/2-bath units with premium finishes.
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ADU Hotline offers affordable ADU design and permitting in Southern California. From granny flats to garage conversions, they handle the full process in 3–4 weeks, helping homeowners add rental income or family housing efficiently.
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Larson Shores Architects is a San Francisco-based firm offering residential, ADU, and commercial design services. Founded in 2007 by Josh Larson, they specialize in new builds, garage conversions, in-law suites, and full permit navigation across the Bay Area.
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Musick Construction Inc. offers ADU construction services including new builds and conversions like garage and basement conversions. They handle permits, design, and finishes for granny flats, in-law suites, and rental units.
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Sprawl-Design offers expert ADU design in San Diego, including garage conversions, attached & detached units. Starting from $60K, they manage design to construction with local expertise & budget clarity.
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Artisan Builders Construction builds ADUs in San Luis Obispo County, CA. Services include detached ADUs, attached units, garage conversions & JADUs. They manage planning, permitting, construction & inspections with transparent pricing.
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MTR (Modern Technology Resources Inc.) offers full-service ADU design and construction in Sacramento, CA. Services include custom builds, garage conversions, permit management, and prefab options—helping homeowners add value with functional, affordable accessory dwelling units.
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OCA Builders offers ADU design & construction in Santa Cruz County, including detached, attached, garage conversion, internal, and Junior ADUs. They use pre-approved floor plans to streamline permitting, saving homeowners time and effort.
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Crest Backyard Homes is San Diego's trusted ADU builder, specializing in prefab, detached ADUs, granny flats & garage conversions. Their all-inclusive team guides homeowners from design to completion, ensuring code-compliant, high-quality accessory dwelling units.
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BuildZig ADU Services is a Bay Area ADU contractor specializing in design, permitting, and construction. They handle garage conversions, detached ADUs, basement/attic conversions, and more, offering transparent pricing throughout.
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ADU Resource Center is a Glendale, CA-based ADU contractor with 600+ completed units. They offer full-service ADU building, including design, permitting, financing, and construction of detached, attached, and garage conversion ADUs across Southern California.
read moreCalifornia 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.
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.
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:
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.
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.