Guide
Wildfire Home Protection — Defensible Space, Vents & Materials
Wildfires have become more frequent and intense due to climate change, drought, and the expansion of development into the wildland-urban interface (WUI). Over 40 million US homes are now at risk. Research from the Insurance Institute for Business & Home Safety (IBHS) and USFS shows that homes can be made significantly more survivable through targeted hardening and landscaping measures.
Leading causes of US home fires
Share of residential fires by cause
- Cooking
Cooking
49 % of fires
- Heating Equipment 15
Heating Equipment
15 % of fires
- Vehicle Fires 14
Vehicle Fires
14 % of fires
- Electrical & Lighting 9
Electrical & Lighting
9 % of fires
- Intentional (Arson) 8
Intentional (Arson)
8 % of fires
- Smoking Materials 6
Smoking Materials
6 % of fires
- Wildland & Brush 5
Wildland & Brush
5 % of fires
- Candles 4
Candles
4 % of fires
What this shows Cooking is the leading cause, accounting for 49% of US home fires. Smoking materials cause a far larger share of deaths than fires — a reminder that the most common causes are not always the deadliest.
1. Defensible Space Zones
Defensible space creates a buffer that slows fire spread and gives firefighters a safer area to defend your home. Most states with wildfire risk require defensible space by law.
- ▸ Zone 1 (0-30 ft): Remove all dead plants and keep grass mowed to 4 inches or less. Space shrubs 10+ feet apart and trees 10+ feet from structures.
- ▸ Zone 2 (30-100 ft): Reduce fuels by thinning brush, trees, and tall grass. Remove ladder fuels (shrubs beneath trees).
- ▸ Zone 3 (100+ ft): Maintain whatever local regulations require; focus on eliminating ignition pathways to structure.
- ▸ Clear gutters, decks, and roof areas of dead leaves and debris weekly during fire season.
- ▸ Replace combustible fencing near the structure with metal or masonry.
2. Home Hardening — Vents and Openings
Most homes are ignited by embers entering through vents, gaps, and eaves — not by direct flame contact. Closing ember entry points is the highest-priority upgrade.
- ▸ Replace attic and eave vents with 1/16-inch metal mesh screens (not fiberglass or plastic)
- ▸ Install ember-resistant vents (CAL FIRE listed) in all roof and wall penetrations
- ▸ Seal any gaps in siding, around pipes, and under eaves
- ▸ Cover weep holes in brick with 1/16-inch mesh
- ▸ Install multi-pane tempered or fire-rated glass windows
3. Fire-Resistant Building Materials
Material choices for roofing, siding, and decking dramatically affect a home's ability to survive wildfire exposure.
- ▸ Roofing: Class A fire-rated shingles (asphalt, metal, clay, or concrete tile) — wood shake is highest risk
- ▸ Siding: Fiber cement, brick, stucco, or metal — avoid vinyl and wood
- ▸ Decking: Composite or non-combustible decking rather than wood
- ▸ Deck undersides: Enclose with fire-resistant material to prevent ember accumulation
- ▸ Fencing: Metal, masonry, or composite materials near the structure
4. Evacuation Planning
Even well-hardened homes can be lost in extreme conditions. Having an evacuation plan ready before fire season is critical.
- ▸ Sign up for local emergency alerts (Wireless Emergency Alerts + county notification systems)
- ▸ Prepare a go-bag with 72 hours of supplies, medications, documents, and irreplaceables
- ▸ Know at least two evacuation routes from your neighborhood
- ▸ Leave EARLY — don't wait for a mandatory evacuation order
- ▸ If you have animals or livestock, plan animal evacuation separately — they need more time
- ▸ Check your county or state forestry agency for local wildfire risk ratings and historical disaster declarations
Read our methodology — how this data is sourced, computed, and verified.
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Understanding the Data
The information presented throughout this guide is informed by publicly available public records published by federal and state government agencies. Our database aggregates and standardizes these records to make them more accessible and easier to interpret for general audiences. When we reference specific statistics or trends, they are drawn directly from these authoritative sources unless explicitly noted otherwise.
It is important to understand the limitations of any large-scale data dataset. Records may contain errors from the original data collection process, some fields may be incomplete for older entries, and classification systems may have changed over time. Our analysis accounts for these factors by clearly labeling data vintage, flagging records with missing critical fields, and noting when temporal comparisons span methodology changes in the source data.
For readers who want to conduct their own research, we recommend going directly to the source whenever possible. federal and state government agencies provides detailed documentation on collection methodology, sampling frames, and known data quality issues. Our goal is not to replace primary sources but to make them more approachable and to highlight patterns that may not be immediately obvious when browsing raw records.
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Key metrics we examine include statistical records, geographic distributions, temporal trends. These indicators provide a multi-dimensional view of each entity in our database, allowing users to understand not just individual records but how they compare to peers, regional averages, and national benchmarks. We believe this contextual approach is far more valuable than presenting raw numbers in isolation.
