Home Additions & ADUs
in Castro Valley, CA
AZ Elevated Builders brings quality-first home additions & adus to Castro Valley, Alameda County. We're a family-run, CA-licensed contractor out of Brentwood, and every trade on our crew has 15+ years in that trade.
A good addition reads as if it was always there — the rooflines continue, the windows match, the proportions hold. We design and build primary-suite additions, kitchen expansions, family rooms and second-story pop-ups that blend into the original house instead of announcing themselves.
Accessory dwelling units are the best investment in California residential construction right now: rental income, space for family, long-term property value. We handle feasibility, the state's evolving ADU rules, local permitting and utilities through final inspection.
Castro Valley's ranchers and hillside homes keep our remodel, concrete and paint crews moving all year.
Home Additions & ADUs services we offer in Castro Valley
- 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
Why Castro Valley homeowners choose us
We're a family business out of Brentwood, and we treat every job like the neighbors are watching — because in this area, they are. Every trade on our crew has 15+ years in that specific trade, estimates are free, financing is available, and the work carries a written warranty of up to five years. Quality over budget, every time. Hablamos español.
Frequently asked questions
Are ADUs 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 give you the real timeline up front and keep you updated weekly.
More services in Castro Valley
Home Additions & ADUs near Castro Valley
Ready to get started?
Tell us about your home additions & adus project in Castro Valley. Estimates are free — and we reply within one business day.
Call (925) 812-3150 Email Us