ADU & Room Addition Contractor in Concord, CA

Design-build ADUs, garage conversions, and room additions — one team from permit to final inspection. Serving Concord and all of Contra Costa County. CA Lic #812248.

Get a Free Quote (925) 405-0588
ADU & Room Addition Contractor

ADU & Room Addition Contractor in Concord, CA

California’s ADU regulations have been dramatically expanded, making it easier than ever for Concord homeowners to add a rental unit, in-law suite, or multigenerational living space. A well-built ADU in the East Bay can add $150,000–$300,000 or more to your home’s appraised value while generating $1,800–$3,500/month in rental income.

We’ve built ADUs throughout Concord, Walnut Creek, Pleasant Hill, Martinez, and Lafayette. We know Concord’s setback requirements, lot coverage rules, and which projects qualify for streamlined permitting — and how to navigate plan check efficiently to minimize your wait time.

Our design-build service covers everything under one contract: architectural drawings, structural engineering, all permits, construction, electrical, plumbing, HVAC, and finishes. One team from concept to certificate of occupancy.

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What’s Included

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Detached ADU (New Construction)

A standalone unit in your backyard. Typically 400–1,200 sq ft with full kitchen, bathroom, and living space. Maximum rental income potential.

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Garage Conversion ADU

Convert your attached or detached garage into a fully permitted ADU. Often the most cost-effective option since the structure already exists.

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Junior ADU (JADU)

Convert an existing bedroom into a self-contained unit up to 500 sq ft. Simpler permitting and lower cost than a full ADU.

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Room Additions

Add a bedroom, expand a living area, or build a home office — a permitted addition that integrates with your home’s existing structure.

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Permits & Engineering Included

We manage all permit applications, structural engineering, Title 24 energy compliance, and all required inspections.

Common Questions

ADU & Room Addition Contractor FAQs

New detached ADUs typically cost $180,000–$280,000 for 400–800 sq ft. Garage conversions run $80,000–$150,000.
From consultation to certificate of occupancy: 7–12 months. City of Concord plan check takes 2–4 months; construction takes 3–5 months.
Most single-family properties can accommodate at least one ADU. We offer free feasibility consultations to review your specific lot, zoning, and setback constraints.

Ready to Build Your ADU?

Serving Concord, Walnut Creek, Pleasant Hill, Martinez, and all of Contra Costa County.

Request a Free Quote (925) 405-0588
Free site visitWritten estimate in 3 days No obligationCA Lic #812248