Attached ADU near Castro Valley, CA

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 m... read more

Mountain Top Construction is a Bay Area ADU builder serving San Rafael, San Francisco, and Las Vegas. They specialize in detached ADUs, backyard cottages, granny flats, and in-law suites, managing design, permitting, and construction.

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.

ADUs (accessory dwelling units) are self-contained homes on existing properties. California's 2020 laws simplified ADU permits statewide. Alpha ADU Solutions, a San Francisco-based ADU builder with 100+ team members, specializes in granny flats, g... read more

We are a family-first, boutique residential design & build firm serving the Orinda and East Bay community. We’re not just service providers — we’re your neighbors. We understand the local permitting process, the hillside terrain, the fir... read more

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.

Quartz Construction builds ADUs in San Jose, including detached units, garage conversions, and in-law suites. ADUs offer extra space, passive rental income, and multigenerational living solutions for Bay Area homeowners.

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 communitie... read more

Custom ADU construction and remodeling services focused on creating functional, comfortable living spaces with quality craftsmanship and reliable workmanship.

We guide you through design options and material choices, taking precise measurements to create a custom plan that perfectly fits your property. This careful planning ensures that your new ADU will seamlessly blend with your existing space and mee... read more

S.D White Construction Inc, a licensed Bay Area ADU contractor with 20+ years experience, builds detached, attached, garage conversion & above-garage ADUs in Richmond, CA. Full-service from design & permits to final inspection, completed i... read more

OT Bay Builders is a complete remodeling company with over 40 years of combined experience amongst our team. We’re expert Bay Area ADU builders in San Jose with a customer-first mindset. As a full-service ADU builder, you can trust us to remain ... read more

Home Revive Builders is a licensed ADU contractor in the Bay Area, CA, specializing in garage conversions, detached ADUs, in-law suites, and more. Full-service projects include design, permits, plumbing, electrical, and finishing.

Atlas General Construction delivers complete ADU construction for detached, attached, and converted structures. Our team manages every phase of development including zoning research, architectural coordination, structural engineering, Title 24 com... read more