Additions & ADUs in Marin County.
Room additions, second-story pops, ADU and JADU builds. We handle the survey, design coordination, permits, and construction.
Why GB Contractors for additions & adus in Marin County.
GB Contractors (legally Golden Bay Contractor LLC, founded by Manuel Escobar in 2004) is a family-owned, CSLB-licensed general contractor based in Novato. We've been doing additions & adus projects across Marin County for two decades. We're based in Novato, central to all of Marin.
→ Home base — we know every Marin building department by first name.
→ Hillside, view-corridor, and fire-zone requirements vary city to city; we manage the permit dance.
→ Two-decade portfolio of Marin homes — our work ages well in this climate.
What's in scope.
Typical line items on a additions & adus we'd run in Marin County. Every bid is line-item — no surprises.
- → Ground-floor additions and bump-outs
- → Second-story additions
- → Detached and attached ADUs
- → Junior ADU (JADU) conversions
- → Foundation work and structural integration
- → MEP rough-in and code compliance
- → Title 24 and energy compliance
- → Permits, including state ADU statute
Working in Marin County.
Most Marin jurisdictions use the California Residential Code with local amendments. Hillside parcels, fire-zone requirements, and Marin County Community Development Agency review are common factors on remodel and addition permits.
We've worked across Marin County's communities — San Rafael, Novato, Mill Valley, Tiburon, Sausalito, San Anselmo, Larkspur, Corte Madera, Ross, Kentfield, Belvedere. Local knowledge of the building department, the design-review patterns, and the building stock isn't a marketing claim for us; it's two decades of repeat work.
Common questions about additions & adus in Marin County.
Does GB Contractors do additions & adus in Marin County?
Yes. Additions & ADUs is one of our core services and Marin County is squarely in our active service area. We're based in Novato, central to all of Marin.
What does a additions & adus cost in Marin County?
Mid-range projects in our portfolio start around $150K. High-end builds with structural changes, premium materials, or custom cabinetry typically run $800K+. Marin County permitting and design-review can add to both timeline and cost — we factor that into bids up front.
How long does a additions & adus take in Marin County?
5 months to 12 months once construction starts, depending on scope and design-review timing. Most Marin jurisdictions use the California Residential Code with local amendments. Hillside parcels, fire-zone requirements, and Marin County Community Development Agency review are common factors on remodel and addition permits.
Are you licensed to work in Marin County?
Yes. GB Contractors (Golden Bay Contractor LLC) holds CSLB License #992507 (Class B General Building), valid statewide in California, and we're fully insured. We pull all required permits and handle inspections directly with the Marin County building department.
Other services in Marin County
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