Napa homeowners need a contractor who understands the unique demands of Wine Country living: fire-resistant construction, seismic resilience, and design that respects the valley's agricultural and architectural heritage. Hamilton Exteriors brings an architect's eye and a general contractor's execution to every project in Napa.
We are a full-service design-build firm led by Alex Hamilton Li, a licensed architect and general contractor (CSLB #1078806). We serve Napa and all of Napa County with roofing, siding, windows, ADUs, home additions, custom homes, and decks. Every estimate is fully itemized, and every project gets a dedicated project manager.
Get Your Free Quote. Call (650) 977-3351 or request an on-site estimate online.
Why Napa Homes Need a Different Kind of Contractor
Building in Napa is not the same as building in the East Bay or the Peninsula. Three factors make Napa distinct:
Fire risk. Most of Napa County is designated Very High Fire Hazard Severity Zone (FHSZ) by CAL FIRE. After the 2017 Tubbs Fire and 2020 Glass Fire, the county requires defensible space inspections and Class A fire-rated roofing materials on all new roofs and re-roofs. Our crews are trained in Chapter 7A compliance — the California Building Code section that governs ignition-resistant construction in Wildland-Urban Interface (WUI) zones.
Seismic risk. The West Napa Fault runs through the valley. The 2014 South Napa earthquake (magnitude 6.0) caused widespread damage to unreinforced masonry and older wood-frame homes. Napa's housing stock includes many pre-1980 homes built before modern seismic codes. We evaluate shear walls, foundation connections, and roof-to-wall ties on every project.
Climate and aesthetics. Napa's hot dry summers (average July high: 82°F, per NOAA) and mild wet winters create specific material demands. Roofing and siding must withstand UV exposure, thermal expansion, and occasional heavy rain. At the same time, Napa's wine-country design conventions — stone, stucco, tile, and natural wood — require materials and finishes that match the valley's character. We work with manufacturers like James Hardie and GAF to deliver fire-rated products that fit Napa's aesthetic.
Our Services in Napa
We handle the full range of residential exterior and interior projects. Every service is available in Napa and the surrounding communities.
Roofing
Asphalt shingles, metal roofing, tile, and flat roofing. We are a GAF Master Elite contractor, a designation held by fewer than 3 percent of roofers nationwide. This certification lets us offer GAF's 50-year system warranty, covering both materials and workmanship. Typical Napa roof replacement costs: $16,000 to $38,000 for asphalt shingles on a standard 2,000 sq ft home, depending on roof complexity and fire-zone requirements. See our roof replacement cost guide for detailed pricing.
Siding
James Hardie fiber cement siding is the most popular choice in Napa's fire-prone areas. It is non-combustible, resists moisture, and comes in styles that match Craftsman, Mediterranean, and contemporary homes. We are a James Hardie Elite Preferred Contractor, the highest tier of certification. Siding replacement typically runs $12,000 to $30,000 for a 1,500 sq ft home.
Windows
Energy-efficient window replacements reduce cooling costs during Napa's hot summers and improve comfort during winter storms. We install vinyl, fiberglass, and aluminum-clad wood windows from manufacturers like Marvin and Milgard. Window replacement costs: $800 to $2,500 per window installed, depending on material and size. See our window replacement services.
ADUs
Accessory Dwelling Units are a smart way to add living space, rental income, or guest quarters to your Napa property. We handle the full process: design, permitting, and construction. Napa County has specific ADU rules under California Government Code Section 65852.2, including ministerial approval for qualifying projects. Typical ADU costs: $150,000 to $400,000 depending on size and finishes. See our ADU cost guide.
Home Additions
Need more space? We design and build room additions, second-story additions, and bump-outs. Every addition requires a structural evaluation for seismic loads and foundation capacity. Typical addition costs: $250 to $600 per square foot. See our home addition cost guide.
Custom Homes
Ground-up custom homes are our most comprehensive service. We work with you from site selection through final inspection, handling all permits, utility connections, and landscape integration. Custom home costs in Napa typically range from $400 to $800 per square foot. See our custom home building services.
Decks
Composite and wood decks that meet Napa's building code requirements for structural load, fire resistance, and railing height. Deck costs: $30 to $60 per square foot installed. See our deck building services.
Permits and Building Codes in Napa
Every project in Napa requires a building permit from the City of Napa Building Division. Permit fees vary by project scope:
- Roof replacement: $300 to $800
- Siding replacement: $150 to $400
- Window replacement: $100 to $300 per window
- ADU: $2,000 to $6,000
- Home addition: $1,000 to $5,000
- Custom home: $5,000 to $15,000
Hamilton Exteriors pulls all permits on your behalf. We handle the paperwork, scheduling, and inspections so you do not have to.
Why Choose Hamilton Exteriors in Napa?
Architect-led. Alex Hamilton Li is both a licensed architect and a general contractor. This dual credential means your project benefits from design thinking and construction expertise from day one. Most Napa contractors are tradesmen-only; we bring an architect's perspective to every estimate and build.
Fire-zone certified. We have completed dozens of projects in WUI zones across Napa County. We know the Chapter 7A requirements for roofing, siding, vents, and decking. We also coordinate with Napa County's defensible space inspection process.
Transparent pricing. Every estimate is fully itemized: materials, labor, permits, and cleanup shown as separate line items. No lump-sum bids, no vague ranges. You see exactly where every dollar goes.
Warranty-backed. As a GAF Master Elite contractor, we offer a 50-year non-prorated material warranty and a 25-year workmanship warranty on roofing. James Hardie siding carries a 30-year non-prorated product warranty. Every project is backed by our general liability and workers' compensation insurance.
Get Your Free Quote
Ready to start your Napa project? Call (650) 977-3351 or request an on-site estimate online. We will walk your property, discuss your goals, and provide a fully itemized estimate., just clear answers.
Hamilton Exteriors. CSLB #1078806. Serving Napa and all of Napa County.
