Wildfire Defensible Space Scorer
Check off what's already true about your home and yard across Zone 0 through Zone 2, and get a numeric score, a ranked list of your highest-impact next steps, and CAL FIRE / IBHS compliance flags. Nothing uploaded.
Checklist
Highest-impact next steps
Understanding wildfire defensible space and home hardening
How defensible space works and the three zones
Wildfire defensible space divides your property into three zones, each with specific clearing and hardening goals. Zone 0 (0-5 feet) is the structure zone: no combustible plants, mulch, or stored materials within 5 feet of the house - just bare soil, gravel, or pavers. Zone 1 (5-30 feet) is for reducing fuel: remove dead vegetation, thin trees so canopies do not touch, space shrubs 10 feet apart, and store firewood 30+ feet away. Zone 2 (30-100 feet) focuses on thinning dense forest to slow an approaching fire. Additionally, home hardening - replacing wood roofing with Class A fire-rated materials, installing 1/8-inch metal mesh vents, and enclosing eaves - prevents embers from igniting your home directly. Together, these measures dramatically reduce the risk that a nearby wildfire will spread to your property.
Who recommends these standards and why they matter
California's CAL FIRE division mandates specific Zone 0 standards for properties in high-fire-risk areas, while the Insurance Institute for Business and Home Safety (IBHS) publishes the broader Wildfire Prepared Home standard, which emphasizes home hardening and vegetation management together. This calculator uses a weighted scoring system based on both standards to assess your property's overall fire resilience. A score above 80 indicates a well-prepared home; 50-80 is moderate risk; below 50 is high risk. Higher-weight items (roof, vents, Zone 0 clearance) have the most impact, so prioritizing those upgrades provides the best return on effort.
FAQ
Do I need to clear Zone 2 if I live in a neighborhood with houses close together?
Zone 2 work (thinning forest beyond 100 feet) is most critical if you are in a wildland-urban interface with dense forest nearby. If your property is surrounded by other homes on small lots with little vegetation, the immediate Zones 0 and 1 are your priority. Check with your local fire department for guidance on your specific area's risk profile.
Is my metal roof alone enough to make my home fire-resistant?
A Class A fire-rated roof is one critical piece, but not enough alone. Embers enter homes through vents, eaves, and gaps in fascia as often as through the roof. A well-prepared home combines a fire-rated roof with sealed vents (1/8-inch metal mesh), enclosed eaves, non-combustible deck skirting, and Zone 0 clearance. All these together dramatically reduce ignition risk.
How much does defensible space work cost?
Zone 0 clearance and basic Zone 1 thinning (removing dead material, spacing trees) can be done with a chainsaw and shovel at minimal cost. Class A roofing, ember-resistant vents, and deck skirting are structural upgrades that range from hundreds to thousands of dollars depending on home size. Many insurers offer discounts for fire-hardening measures, sometimes offsetting upgrade costs over time. Consult a contractor or your local fire department for estimates.