ADU Contractors near Diamond Bar, CA
WM Construction
10535 Foothill Boulevard, Rancho Cucamonga, CA 91730
16.7 miles
WM Construction is a licensed ADU contractor in Los Angeles offering full-service builds, from site assessment and design to permitting and post-construction support, helping homeowners add granny flats, garage conversions, and in-law suites compliantly.
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UNI Construction
1142 South Diamond Bar Boulevard, Diamond Bar, CA 91765
1.3 miles
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.
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Esco Builders Inc
Downey, CA 90242
19.4 miles
Avica Construction & Development Inc
357 West Route 66, Glendora, CA 91740
9.4 miles
Avica Construction & Development Inc is a licensed LA-based ADU contractor building detached ADUs, garage conversions, attached ADUs & JADUs across Los Angeles, Orange County & San Bernardino County, managing design, permits & construction.
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The ADU Company
504 East Navilla Place, Covina, CA 91723
6.7 miles
The ADU Company, a licensed ADU contractor in Covina, CA, serves greater Los Angeles with expert accessory dwelling unit design and construction, including garage conversions, detached ADUs, JADUs, home additions, remodels, and more.
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Legacy Builders LA
Los Angeles, CA
24.7 miles
Legacy Builders LA is a trusted ADU contractor in Los Angeles with 20+ years of experience. They offer ground-up ADUs, JADUs, garage conversions & additions, delivering custom, high-quality accessory dwelling units tailored to each homeowner.
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EHD Builders
18375 Ventura Boulevard, Tarzana, CA 91356
43.1 miles
EHD Builders offers ADU construction services in Los Angeles, CA, including garage conversions, detached units & additions. Costs range from $150K–$350K+. Services cover permits, framing, plumbing, electrical & more.
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iHome Design & Remodel
614 South Euclid Street, Fullerton, CA 92832
11.8 miles
iHome Design & Remodel specializes in custom ADU and casita construction, offering full-service builds from design to completion. Services include garage conversions, detached ADUs, permit handling, and free 3D consultations for homeowners.
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BuildForm Design
14401 Sylvan Street, Van Nuys, CA 91401
38.9 miles
BuildForm Design is a Los Angeles general contractor offering full-service ADU design, build, and value engineering. With 15 years of experience, they handle basement conversions, detached ADUs, garage conversions, and more across Southern California.
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California ADU Center INC
7542 Laurel Canyon Boulevard, Los Angeles, CA 91605
33 miles
California ADU Center INC specializes in ADU planning, design, and construction across California. Services include detached ADUs, garage conversions, JADUs, granny flats, and in-law suites. They manage permitting and navigate California's ADU regulations for homeowners.
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ADU Conversion
Los Angeles, CA
24.7 miles
ADU Conversion is a California-based ADU contractor specializing in detached ADUs, garage conversions, Junior ADUs, and attached units. They manage design, permitting, and construction, ensuring compliance with California ADU laws for homeowners seeking rental income or multigenerational housing.
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Otto ADU
2926 Denby Avenue, Los Angeles, CA 90039
28 miles
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.
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San Gabriel Valley ADU
1841 South San Gabriel Boulevard, Rosemead, CA 91776
16.8 miles
San Gabriel Valley ADU Construction Contractors build & convert ADUs, granny flats, garage conversions & in-law suites across Pasadena, Arcadia & nearby cities. Expert permitting, design & cost management for LA County homeowners.
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Baum Construction & Development Inc
2900 Fidler Avenue, Long Beach, CA 90815
23 miles
ADUs (accessory dwelling units) are self-contained homes on existing properties, ideal for rentals or multi-generational living. Costs range $100K–$200K. Baum Construction & Development Inc builds ADUs in Long Beach, CA.
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New Dawn Construction
14900 Ventura Blvd Unit #330, Sherman Oaks, CA 91403
38.5 miles
New Dawn Construction is an ADU contractor specializing in detached ADUs, garage conversions, in-law suites, granny flats, JADUs, and backyard cottages. They guide homeowners through design, permitting, and construction for flexible housing solutions.
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Other cities in California
What you need to know
ADU Contractors in Diamond Bar: Building in the "Country Living" City of Los Angeles County
Diamond Bar, California, famously known as the "Country Living" city, is a suburban community nestled in the eastern San Gabriel Valley of Los Angeles County. With its hillside terrain, large residential lots, and strong emphasis on quality of life, Diamond Bar presents unique opportunities and challenges for ADU (Accessory Dwelling Unit) contractors. The city's hilly topography often means that ADU projects require specialized grading, foundation work, and slope analysis — making it essential to hire experienced local ADU contractors who understand Diamond Bar's specific landscape and municipal requirements.
ADU Regulations and Permitting in Diamond Bar
Diamond Bar follows California state ADU laws (AB 68, AB 881, SB 13, and AB 3182) while also enforcing its own local zoning ordinances. ADU contractors working in Diamond Bar must navigate the city's Development Services Department for permits. Key regulations include:
- Setback requirements: Detached ADUs generally require a minimum 4-foot rear and side yard setback.
- Maximum ADU size: Detached ADUs can be up to 1,200 square feet, while attached ADUs are limited to 50% of the primary dwelling's square footage.
- Height limits: Detached ADUs are typically limited to 16 feet in height, though this can vary based on lot conditions.
- Owner-occupancy: As of January 1, 2020, California law removed owner-occupancy requirements for ADUs through 2025.
- Hillside and slope considerations: Given Diamond Bar's terrain, contractors must often comply with additional grading permits and geological reports.
Types of ADUs Built by Diamond Bar Contractors
Experienced ADU contractors in Diamond Bar are skilled in constructing a variety of ADU types suited to the city's residential neighborhoods, including areas like The Country Estates and South Pointe. Common ADU types include:
- Detached ADUs: Standalone structures built in the backyard, ideal for larger lots common in Diamond Bar.
- Attached ADUs: Units added directly to the existing home, maximizing space on sloped properties.
- Garage Conversion ADUs (JADUs): Converting existing garages into livable units, a cost-effective option for many homeowners.
- Junior ADUs (JADUs): Units up to 500 square feet created within the existing primary residence.
Why Hire a Local ADU Contractor in Diamond Bar?
Hiring a local ADU contractor familiar with Diamond Bar is critical for a smooth and compliant build. Local contractors understand the city's Los Angeles County Fire Department requirements, utility connection protocols, and the nuances of building on hillside lots. They also have established relationships with the Diamond Bar Development Services Department, which can help streamline the permitting process and avoid costly delays.
Whether you're looking to add rental income, house extended family, or increase your property value, working with a qualified ADU contractor in Diamond Bar, CA ensures your project meets all state and local standards while making the most of your property's unique potential.