Home Additions & ADUs
in Castro Valley, CA
We offer home additions & adus in Castro Valley, Alameda County. Our family-run crew is based in Brentwood, with 15+ years of experience in each trade.
Who offers home additions & adus in Castro Valley, CA?
AZ Elevated Builders provides home additions & adus in Castro Valley, California. We are a family-run, licensed and insured general contractor based in Brentwood, serving Castro Valley and the surrounding Alameda County area. Estimates are free, every trade on our crew has 15+ years of experience, and all work carries a written warranty of up to five years. We speak English and Spanish. Call (925) 812-3150.
We design and build primary-suite additions, kitchen expansions, family rooms and second-story additions. Rooflines, windows and finishes are planned to work with the existing house.
An ADU can provide space for family or a rental unit. We handle feasibility, California's ADU requirements, local permitting and utilities through final inspection.
Planning your project in Castro Valley
We offer remodeling, concrete and painting services throughout Castro Valley.
The local housing includes 1950s–70s ranch homes with newer custom builds up the canyon. Some post-war properties have space for an addition or ADU. We assess the lot and any existing garage during the feasibility review.
We serve Castro Valley, including Palomares Hills, Five Canyons, Proctor and Lake Chabot area. Project planning here accounts for canyon lots, sloped driveways and fire-zone requirements in the upper hills. We assess foundations, drainage and space on the lot when planning an addition or detached unit.
Permits and inspections in Castro Valley
Permits for work in Castro Valley go through Alameda County Building Inspection, since Castro Valley is unincorporated. Additions and ADUs are the most review-heavy work we do — setbacks, lot coverage, utilities and California's ADU rules all get checked before a shovel moves. We handle the permit application and coordinate inspections.
What's included
- Room additions & home extensions
- Primary suite & bath additions
- Detached & attached ADUs
- Garage conversions
- Feasibility & permit management
- Utility connections & upsizing
- Full kitchens & baths in every unit
- Finish levels matched to the main house
What to expect
Contact us to schedule a walkthrough in Castro Valley. We provide free estimates, a written schedule and a warranty of up to five years. Hablamos español.
Frequently asked questions
Are ADUs legal in Castro Valley?
Yes — ADUs are legal in Castro Valley. California law requires cities to allow ADUs on most residential lots, and Castro Valley processes them under those state rules. We confirm setbacks, size limits and utility requirements for your specific parcel during the free feasibility visit.
What does an ADU cost to build?
It varies with size, site and finish level — a garage conversion is a different project than a detached new build. We price it in a written scope after walking your property, and financing options are available.
How long does an addition take?
Design and permitting typically run 2–4 months depending on the city; construction runs 3–6 months for most additions and detached ADUs. We provide a written schedule and keep you updated weekly.
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Home Additions & ADUs near Castro Valley
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