ADU Contractors in California
Pro-built Homes
112 King Street, New Brunswick, CA E1N 2N6
Pro-built Homes builds factory-constructed Accessory Dwelling Units (ADUs) delivered 99% complete. Ideal as in-law suites, rental units, or backyard cottages, their ADUs offer quality, speed, and long-term value with minimal on-site disruption.read more
ADU Custom Homes
1420 East Katella Avenue, Orange, CA 92867
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 ... read more
UNI Construction
1142 South Diamond Bar Boulevard, Diamond Bar, CA 91765
UNI Construction builds detached and attached ADUs, handling site planning, structural engineering, and permit-ready drawings. Options include backyard cottages, granny flats, and in-law suites, all code-compliant and tailored to your property.read more
Otto ADU
2926 Denby Avenue, Los Angeles, CA 90039
Otto ADU is a licensed Los Angeles ADU builder specializing in garage conversions, detached ADUs, JADUs & granny flats. Serving LA County with 100+ completed units, adding avg. $185K in home value.
read more
Garage Conversion by Pearl Remodeling
6803 Yarmouth Avenue, Reseda, CA 91335
Pearl Remodeling is a Los Angeles ADU contractor specializing in garage conversions, granny flats & in-law suites. With 10+ years experience, they handle design, permits & construction under California's SB-1069 ADU laws.
read more
Olive City Construction, LLC
3039 Orchard Avenue, Corning, CA 96021
Olive City Construction, LLC is a Northern California ADU contractor serving Chico. They offer tiered packages for accessory dwelling units, financing options including 0% APR, and handle permitting, garage conversions, granny flats, and detached ... read more
Urban Building Workshop
130 Bush Street, San Francisco, CA 94104
Urban Building Workshop is a full-service architecture firm in the Bay Area specializing in custom homes, remodels, and ADUs. Experts in Marin County, San Francisco, and Sonoma County permitting, they deliver efficient, light-filled designs.
read more
Humbuildt Homes
1250 Giuntoli Ln, Arcata, CA 95521
Humbuildt Homes is an Arcata, CA general contractor specializing in sustainable prefabricated homes for Humboldt County. They offer affordable, energy-efficient housing guided by integrity, innovation, and quality, with a streamlined build process... read more
DREC Construction Services
15338 Central Avenue, Chino, CA 91710
DREC Construction Services is a licensed ADU builder in Glendale, CA, with 10+ years of experience. They handle design, permitting, and construction of ADUs for rental income, family housing, and home offices, offering a transferable lifetime warr... read more
Beach Builders Custom Homes
13001 Seal Beach Boulevard, Seal Beach, CA 90740
Beach Builders Custom Homes offers full-service ADU and garage conversion services in Los Angeles and Orange County. From permits to construction, they build granny flats, backyard cottages, and JADUs with smart home tech, earning homeowners $1,20... read more
JL Biber Construction Inc.
15548 Saddleback Road, Riverside, CA 92506
An ADU is a secondary residential unit on the same property as a primary home. JL Biber Construction Inc., a licensed ADU builder in Riverside, California, offers full-service garage conversions, granny flats, and detached ADU construction.
read more
BSPK Design
685 Venice Boulevard, Venice, CA 90291
BSPK Design is a Venice, CA residential studio founded by Chris Faulhammer & Roman Reiterer, with 50+ years combined experience. Services include custom homes, fire rebuilds & prefab NextGen Building. Multiple Houzz Best of Design award wi... read more
Geico Builders
1901 Harrison Street, Oakland, CA 94612
Geico Builders offers ADU services including detached ADUs, attached ADUs, Junior ADUs, garage conversions, and home additions. Ideal for rental income, family housing, or maximizing space on your existing property.
read more
SOD Home Group
367 Santana Hts, San Jose, CA 95128
SOD Home Group builds attached & detached ADUs, including granny flats, in-law suites, garage conversions & backyard cottages. Licensed ADU contractor (Lic. 942085) helping homeowners expand living space efficiently.
read more
Jackson Design & Remodeling
4797 Mercury Street, San Diego, CA 92111
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.