Detached ADU near Petaluma, CA

DSA Architects designed an 850 sq. ft. second-floor ADU in Berkeley Hills for multi-generational living. Features 2 beds, 1 bath, open layout, Tilden Park views, roof deck, solar PV, heat pumps, and gray-water system.

Colibri Kitchen & Bath offers full-service ADU construction in Oakland, handling design, permitting, and building. Services include site assessment, architectural plans, 3D renderings, and complete construction from foundation to finishing.

Harmony Design & Development builds custom ADUs across the San Francisco Bay Area, including detached units, garage conversions, and in-law suites. They manage permits, design, and construction from start to finish.

Your Prefab ADU will be delivered and installed to your site. All ready to enjoy a sustainable home to last for generations.

LRL Builders, Inc. is a licensed ADU contractor in Walnut Creek, CA, specializing in detached, attached, garage conversion, and junior ADUs. They handle design, permitting, and construction, serving Walnut Creek and surrounding Bay Area communities.

Shed Shop offers ADUs (Accessory Dwelling Units) via their Mini Cottage program. Sizes range from 192 to 480 sq. ft. Services include foundation, plumbing, electrical, permits & more. Available in select cities.

J.A. Mejia Construction is a licensed ADU builder & home addition contractor in Sonoma County & the Bay Area. Services include detached ADUs, garage conversions, in-law suites & second-story additions in Santa Rosa, Petaluma & beyond.

Edri Construction, Inc. in Burlingame offers full-service ADU construction across the Bay Area, including garage conversions, detached ADUs, attached additions, and custom interiors, with energy-efficient builds and multi-generational living solutions.

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.

Todd Jersey Architecture (TJA) is a Berkeley-based sustainable design firm serving the SF Bay Area. Specializing in ADUs, remodels, new homes & historic preservation, TJA combines 30+ years of experience with a performance-driven, eco-conscious approach.

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.

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.

Karl Kardel Company offers home remodeling, additions, and ADU construction in Oakland, Pasadena, and the Bay Area. Services include detached ADUs, garage conversions, granny flats, kitchen and bathroom renovations for residential properties.

RWB Construction is a Lafayette, CA-based ADU contractor serving the Bay Area. They build detached ADUs, garage conversions, granny flats & in-law suites, managing design, permitting, and construction from start to finish.

Excellent Home Remodeling offers professional home addition services in Sonoma, helping homeowners expand living spaces, add bedrooms, bathrooms, home offices, or in-law suites. They handle planning and execution tailored to each property's needs.