Belz Construction is a Sacramento ADU contractor building custom accessory dwelling units, in-law suites, garage conversions, and ADA-compliant granny flats. They manage design, permits, and construction end-to-end, boosting property value by up to 30%.
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Perfect ADU & Remodeling Inc specializes in ADU construction, including detached ADUs and garage conversions. Services cover design, permitting, and build. ADUs boost property value, enable rental income, and support multi-generational living.
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BNC Builders Inc. is a San Diego County ADU contractor offering detached, attached, garage conversion & JADU construction. Services include permit management, custom design & financing assistance.
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Joy Line Homes offers the ADURA ADU Series — factory-built backyard cottages and granny flats featuring modern design, high-end finishes, and durable materials. An affordable, plan-based ADU solution for homeowners seeking quality detached accessory dwelling units.
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3 Day Kitchen & Bath is a trusted ADU contractor in San Diego offering full-service accessory dwelling unit construction. From garage conversions to detached ADUs, they manage every project phase with a structured, professional approach.
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S.D White Construction Inc, a licensed Bay Area ADU contractor with 20+ years experience, builds detached, attached, garage conversion & above-garage ADUs in Richmond, CA. Full-service from design & permits to final inspection, completed in 3–5 months.
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ExpandADU is a California-based prefab ADU builder offering full-service accessory dwelling unit construction, including consultation, design, planning, and build. Serving the Bay Area and beyond, they specialize in detached ADUs, granny flats, and JADUs.
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Ingenious General Construction is a BBB-certified, licensed contractor in Walnut Creek, CA, serving the East Bay. With 20 years of experience, they offer ADUs, kitchen & bathroom remodeling, home additions, pool construction, and landscaping.
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ON Design & Remodeling is a Bay Area ADU builder offering home additions, garage conversions, granny flats, and in-law suites. They help homeowners expand living space, boost property value, and generate rental income.
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ADU Custom Homes is a licensed California ADU contractor with 35+ years of experience serving LA, Orange & Riverside counties. They specialize in detached ADUs, garage conversions & additions, managing projects from permits to Certificate of Occupancy.
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Ivy Builders is a top ADU contractor in Los Angeles & Orange County, specializing in detached ADUs, granny flats & backyard cottages. Offering pre-approved plans, full permitting, and custom builds ranging from $200K–$500K.
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Feldman Construction specializes in custom ADU design and construction across the Bay Area, including San Mateo and Santa Clara County. They build detached ADUs, granny flats, and in-law suites to boost property value and expand living space.
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Bundle ADU is a California-based full-service ADU contractor offering custom accessory dwelling units from 400–1,200 sq ft, starting at $200/sq ft. Services include design, permitting, and construction with ~4-month build times.
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Mee Builders is a San Diego ADU contractor offering detached, attached, garage conversion, above-garage, and JADU construction. They ensure California Energy Code compliance, local permitting, and maximize density under San Diego zoning regulations.
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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 performance.
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.