Homeowner's Guide to Wildfire Preparedness
Defensible space, home hardening, and Fire Hazard Severity Zones for California homeowners. Properties in State Responsibility Areas or Very High Fire Hazard Severity Zones face specific statutory requirements.
Fire Hazard Severity Zones
CAL FIRE classifies lands within State Responsibility Areas into Fire Hazard Severity Zones (FHSZ) under Public Resources Code §§4201–4204, based on vegetation, topography, weather, and crown-fire potential.
| Zone | Risk Level | Description |
|---|---|---|
| Moderate | Lowest FHSZ | Areas with moderate fire hazard potential |
| High | Elevated FHSZ | Substantial fire hazard from vegetation and terrain |
| Very High | Highest FHSZ | Greatest fire hazard; subject to the most stringent requirements |
A property's location within an FHSZ must be disclosed under California Civil Code §1103 as part of the Natural Hazard Disclosure Statement.
Defensible Space Requirements
Public Resources Code §4291 requires owners in SRA and VHFHSZ areas to maintain defensible space — the buffer between a building and surrounding vegetation that slows a wildfire's spread.
- Zone 0 — Ember-Resistant (0–5 ft): hardscape and non-combustible materials only; remove all dead vegetation. Added by AB 3074, effective 2023.
- Zone 1 — Lean, Clean & Green (5–30 ft): remove dead plants, trim tree limbs 6–10 ft off the ground, space shrubs and trees, keep grass under 4 inches.
- Zone 2 — Reduced Fuel (30–100 ft): space tree canopies, remove ground litter and dead vegetation, keep grass under 4 inches.
Home Hardening
Ignition-resistant materials and construction dramatically improve a structure's chance of surviving a wildfire. Key areas:
- Roof: Class A fire-rated materials; keep gutters clear.
- Vents: cover with 1/8-inch metal mesh to block embers.
- Eaves: box in or use ignition-resistant materials.
- Windows: dual-pane or tempered glass.
- Walls: stucco, fiber cement, or masonry siding.
- Decks & fences: non-combustible materials; keep the area beneath decks clear.
Defensible Space Inspection Upon Sale (AB 38)
Assembly Bill 38 requires that, upon sale of property in a high or very high fire hazard severity zone, the seller provide the buyer with documentation of a compliant defensible-space inspection. Inspections may be performed by CAL FIRE, a local fire authority, or a qualified third-party inspector.
Insurance Considerations
Properties in high fire hazard areas may struggle to obtain or retain coverage. The California FAIR Plan provides basic fire insurance when the standard market is unavailable, and defensible-space and home-hardening improvements may help qualify for reduced premiums.
Applicable Statutes
- Public Resources Code §§4201–4204 — Fire Hazard Severity Zones
- Public Resources Code §4291 — Defensible Space
- Government Code §§51175–51189 — Very High Fire Hazard Severity Zones
- Civil Code §1103 — Natural Hazard Disclosure
- AB 38 (2019) — Defensible Space Inspection Upon Sale
- AB 3074 (2020) — Ember-Resistant Zone (Zone 0)
Bottom Line
Defensible space plus home hardening is the proven combination for wildfire survival. Sellers in high and very high fire hazard zones must disclose the zone and provide a defensible-space inspection at sale. Learn more at readyforwildfire.org.