Prefab / Modular ADU near Union City, CA

ADU Premium builds eco-friendly, RVIA-certified tiny homes and ADA-accessible ADUs. Models range from 90–360 sq ft, starting at $49,200. Includes permits, delivery, and installation. Financing available via RV loans, HELOC, and more.

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.

Roof and Realm is a California-based steel-framed modular home and ADU builder offering fire, earthquake, and wind-resistant structures. Their eco-friendly builds use 98% recyclable materials, generate minimal waste, and support solar-ready, Net Positive energy designs.

Jaws Construction Services builds ADUs, garage conversions, and JADUs. They handle permits, HOA coordination, and offer site-built or prefab options. East Bay ADUs rent for $1,500–$3,500+/month, potentially boosting property value.

Type Five is a Berkeley, CA-based ADU builder offering custom backyard cottages, granny flats & in-law suites. They combine modular design, transparent pricing & streamlined construction for stress-free, high-quality detached ADUs built to last.

Eagle ADU is a licensed ADU builder in Northern California offering three signature models: Eagle Studio ($180K–$220K), Eagle One ($230K–$280K), and Eagle Two ($310K–$360K), with rental income potential up to $4,000/month.

Bay Builders & Remodeling specializes in custom ADU construction across Santa Clara, San Mateo, and East Bay. Services include attached, detached, garage conversions, and JADUs, helping homeowners add rental income, family housing, or workspace.

CityPaks is a minority & woman-owned ADU builder in the San Francisco Bay Area specializing in affordable, sustainable backyard cottages & detached ADUs using SIP panels. No crane needed, no sales tax, pre-approved in San Jose.

Bay Area Home Remodelers builds ADUs in Daly City, San Francisco & San Jose. Services include garage conversions, granny flats, JADUs & detached units. Full project support from permits to completion.

Haus+ is a Bay Area ADU builder offering turnkey accessory dwelling units for California homeowners. They handle design, permitting, and construction using a panelized hybrid method, with all-inclusive upfront pricing and in-house financing available.

prefabADU is a Bay Area ADU builder with 16+ years of experience offering affordable kits and plans from under $45K. With 12 state-approved plans valid across California, they simplify permits, design, and installation for homeowners.

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.

Elite Construction builds ADUs in Santa Cruz County, offering detached units, garage conversions & addition ADUs. Projects range 250–1,200 sq ft, cost $115K–$450K, and take 6–9 months. Free estimates available.

Nestadu is a full-service ADU builder offering custom site-built and prefab accessory dwelling units. Prefab models range from $115K–$317K. Custom builds start at $400/sq ft. Financing options include HELOCs, construction loans, and CA grants.