Attached ADU near Castro Valley, CA
Luma Dwellings Home Builder
63 Hazel Tree Ridge, Orinda, CA 94563
13.7 miles
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 fire-hazard restrictions, and the thoughtful planning needed to create homes that truly work for East Bay families.
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California Bay Builders & Remodeling
2150 N 1st Street Suite 400, San Jose, CA 95131
24.2 miles
Bay Area design-build ADU specialists. One project, one point of contact — design, engineering, permitting, and construction from start to finish. CSLB #1130783.
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Reno Revive Remodeling
2655 Stanwell Drive, Concord, CA 94520
19 miles
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.
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Excellent Home Remodeling
1310 Alma Avenue, Walnut Creek, CA 94596
12.8 miles
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.
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ProStruct Engineering
450 Folsom Street, #1502, San Francisco, CA 94105
19.7 miles
ProStruct Engineering offers ADU structural engineering services across California, providing permit-ready plans and calculations for detached ADUs, garage conversions, granny flats, and more, with a 2–3 week turnaround.
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Step-up Construction
398 Bay Street, San Jose, CA 95123
34.7 miles
Step-up Construction is a San Jose ADU contractor specializing in garage conversions, attached additions, and detached backyard ADUs. Costs range from $80K to $475K. They guide homeowners through permits, zoning, and San Jose's ADU regulations.
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Barzel Builders
4039 Transport Street, Palo Alto, CA 94303
19.7 miles
Barcci Builders
16185 Los Gatos Boulevard, Los Gatos, CA 95032
33.3 miles
Barcci Builders specializes in ADU construction across the Bay Area, offering design, permitting, and build services. With 40+ completed units, they handle JADUs, garage conversions, attached, and detached ADUs, with costs ranging from $60K to $400K+.
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Intelligent Choice Builders
1437 Park Avenue, San Jose, CA 95126
27.4 miles
Intelligent Choice Builders is a licensed Bay Area ADU contractor serving Palo Alto, Cupertino, San Jose & Sunnyvale. They build detached ADUs, garage conversions, granny flats & more, managing permits, design & construction end-to-end.
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ExpandADU | Prefab ADUs
41111 Mission Boulevard, Fremont, CA 94539
15.8 miles
ExpandADU is a California-based prefab ADU builder offering full-service accessory dwelling unit construction, including consultation, design, planning, and build. Serving the Bay Area and beyond, they specialize in detached ADUs, granny flats, and JADUs.
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S.D White Construction Inc
1151 Hensley Street, Richmond, CA 94801
23.3 miles
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 in 3–5 months.
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Jeff Martinez Construction
11 Susie Ct, Oakley, CA 94561
28.2 miles
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.
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Greenwood Custom Builders, Inc.
765 Old County Road, San Carlos, CA 94070
17.7 miles
SOD Home Group
367 Santana Hts, San Jose, CA 95128
27.6 miles
SOD Home Group builds attached & detached ADUs, including granny flats, in-law suites, garage conversions & backyard cottages. Licensed ADU contractor (Lic. 942085) helping homeowners expand living space efficiently.
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Spruce ADU Builders Union City
3909 Smith Street, Union City, CA 94587
7.8 miles
Spruce ADU Builders is a licensed ADU contractor in Union City offering expert accessory dwelling unit construction. Services include granny flats, in-law suites, and custom ADUs with free consultations, transparent pricing, and a 100% satisfaction guarantee.
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What you need to know
Searching for top Attached ADU ADU Contractors in Castro Valley, California? Our directory highlights trusted local professionals who specialize in designing and building accessory dwelling units (ADUs).
Working with a qualified Attached ADU ADU Contractor in Castro Valley ensures your ADU project meets local building codes, zoning laws, and permit requirements. Whether you're planning a detached ADU, garage conversion, or backyard cottage, experienced Attached ADU professionals can guide you through every step.
Castro Valley homeowners are increasingly investing in ADUs to create additional living space, generate rental income, or support multigenerational living. The Attached ADU experts featured here bring local expertise and proven experience to help make your project a success.
Browse our listings to find the best Attached ADU ADU Contractors in Castro Valley, California, and get started today.