Napa, CA Fire Regulations: Brush Clearance (2026)

Napa sits in one of California's most fire-prone landscapes — the 2017 Atlas Fire and 2020 Glass Fire together destroyed thousands of structures across Napa and Sonoma counties. Defensible space is governed by three overlapping layers. (1) California Public Resources Code Section 4291 requires 100 feet of defensible space around every habitable structure on land covered with flammable material in CAL FIRE State Responsibility Areas — split into Zone 1 (0-30 feet) of lean/clean/green vegetation and Zone 2 (30-100 feet) of reduced and spaced fuel. Most parcels on the east and west hillsides ringing the City of Napa are inside the CAL FIRE Sonoma-Lake-Napa Unit (LNU) SRA. (2) California Government Code Section 51182 imposes the same 100-foot requirement on parcels in Local Responsibility Area Very High Fire Hazard Severity Zones — and the Office of the State Fire Marshal released updated LRA FHSZ maps for Napa in February 2025 that significantly expanded Very High coverage in the hillsides above Browns Valley, Alta Heights, Silverado, the eastern foothills above Coombsville, and the northern edge of the city. AB 3074 added a noncombustible Zone 0 from 0-5 feet around any structure (no wood mulch, no combustible patio furniture, no woody plants against siding). (3) Napa Municipal Code weed-abatement provisions declare dry weeds, dead vegetation, and rubbish that creates a fire hazard a public nuisance, with annual inspection cycles by Napa Fire Department personnel.