Detached ADU near Castro Valley, CA

Bayside Builders Group is a licensed Bay Area ADU contractor with 25+ years of experience. Services include detached ADUs, garage conversions, and in-law suites. Serving Oakland, San Jose, San Francisco, and surrounding counties.

Jeff Martinez Construction Inc. builds ADUs in Oakley, CA with 27+ years of experience. Services include detached ADUs, garage conversions, permits, finishing, and landscape integration across Contra Costa County.

Crane Construction is a licensed Bay Area general contractor based in Walnut Creek, CA. They specialize in design-build projects, ADUs, garage conversions, remodeling, and new construction for residential and commercial clients. Free estimates available.

ADU Builders Bay Area specializes in detached ADUs, garage conversions, in-law suites & more. Expert ADU contractors offering transparent pricing, full permitting & quality construction throughout the Bay Area.

NorCal ADU Builders is a California-based full-service ADU contractor handling planning, permits, Title 24 compliance, and construction—including foundation, framing, roofing, plumbing, and interior finishes—for detached ADUs, garage conversions, and backyard cottages.

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.

Gordon Reese Design Build is a licensed ADU contractor in Walnut Creek, CA, with 41+ years of experience. They offer custom ADU design and construction, 3D renderings, transparent pricing, serving the Bay Area including Danville, Lafayette & Concord.

Whether you’re planning a rental unit, a guest house, or a private suite for family, RenoRevive will help you design and build a fully functional ADU that fits your needs, your lot, and your long-term goals.

Vargas Construction is a California ADU contractor offering detached, attached, garage, junior, and multifamily ADUs. They handle design, permitting, and construction with energy-efficient materials, custom interiors, and full amenities in 2–6 months.

Optivest Build is a licensed general contractor offering ADU construction, garage conversions, home additions, renovations, and new builds. They manage permits, design, and inspections, delivering residential and commercial projects on time and within budget.

Atra Construction is a Bay Area ADU contractor offering full-service design and build. They handle permits, planning, and construction management. Floor plans range from 240 sq ft studios to 1,200 sq ft three-bedroom units.

Dwelling Lab is an Oakland-based ADU design firm offering full-service planning, schematic design, construction drawings, permitting, and construction oversight for detached ADUs, attached additions, and garage conversions.

Kaplan Architects added a 280 sq ft ADU to an existing garage in Crocker Highlands, Oakland. Built into a hillside, it features a kitchenette, full bath, and Tudor-style exterior, serving as office, studio, or rental unit.