ADU Contractor in Brentwood

We serve six Bay Area counties — Alameda, Contra Costa, Marin, Napa, San Mateo, and Santa Clara — covering 47 cities from Oakland to San Jose. Our crews are based in Castro Valley, putting us within 45 minutes of every city we serve. We handle permits and know the building codes for each jurisdiction, which matters because requirements and fees vary significantly between cities.

We offer $0-down financing with approved credit, 12-month same-as-cash plans, and extended terms up to 15 years for larger projects. You only pay for completed, inspected work — we never ask for full payment before the job is done. Your project manager will walk you through every option during your estimate appointment. We also accept checks, ACH, and all major credit cards.

Yes. CSLB License #1078806 — verify it anytime at cslb.ca.gov. We carry $2M general liability, full workers’ comp, and are bonded per California law. We hold GAF Master Elite, Owens Corning Preferred, CertainTeed ShingleMaster, and James Hardie Elite Preferred certifications — each requires annual training and quality audits to maintain. We’re happy to provide proof of insurance before any work begins.

Most exterior projects in the Bay Area require a building permit. Fees vary by city — Oakland runs $200–$600, Peninsula cities often more. We handle the entire permit process: application, plan submission, and scheduling inspections. Permit fees appear as a separate line item in your estimate so you’ll see every cost upfront. For homes in WUI fire zones (Berkeley Hills, Oakland Hills, parts of Marin), we ensure full compliance with local fire-rated material requirements.

ADU construction in Brentwood typically ranges from $150,000 to $350,000 depending on size, finishes, and site conditions. Garage conversions start lower while detached new builds cost more.

California's ADU laws allow construction on most residential lots in Brentwood. We evaluate your property's potential during a free consultation, including setbacks, utilities, and zoning compliance.

From design to move-in, an ADU in Brentwood typically takes 8-14 months. Permitting accounts for 2-4 months, with construction taking 4-8 months depending on complexity.

Under California law, most single-family lots in Brentwood can accommodate an ADU regardless of lot size. Setback requirements are typically 4 feet from side and rear property lines.

Brentwood homeowners can build detached ADUs (up to 1,200 sq ft), attached ADUs, garage conversions, or JADUs (up to 500 sq ft within the existing home). Each type has different cost and timeline considerations.

Yes. ADUs in Brentwood can be rented at market rates with no owner-occupancy requirement for properties with only one ADU. This makes them an excellent investment for rental income.

Detached ADUs in Brentwood require 4-foot side and rear setbacks. Converted garages and structures within the existing footprint may qualify for reduced setback requirements.

ADUs in Brentwood typically add 20-30% to property value while generating $2,000-$3,500 monthly rental income. The combination of equity growth and cash flow makes ADUs a strong investment.

Brentwood homeowners can finance ADUs through home equity loans, cash-out refinancing, construction loans, or the California ADU Grant Program. We help connect you with experienced ADU lenders.

A Junior ADU (JADU) is a unit up to 500 sq ft created within your existing home footprint. JADUs in Brentwood have simplified permitting and lower construction costs, typically $50,000-$100,000.