Home hardening: the 29-point checklist

Home hardening is the set of building and landscape changes that keep your house from igniting when a wildfire moves through. It's not about stopping the fire — it's about removing the small openings, materials, and debris that let embers turn a near-miss into a total loss.

Post-fire studies by IBHS, NIST, and CAL FIRE consistently show the same pattern: when neighbors lose their homes and one survives, the survivor almost always has a Class A roof, clean gutters, ember-resistant vents, and nothing flammable within 5 feet of the walls. The surviving home is rarely the newest, biggest, or most expensive — it's the one whose owner did the unglamorous work.

California Building Code Chapter 7A codifies most of these requirements for new construction in wildland-urban interface (WUI) zones. The 29-point FireScores checklist mirrors Chapter 7A plus the IBHS Wildfire Prepared Home standard, applied as a retrofit guide for existing homes.

1. Class A fire-rated roof covering (composition shingle, metal, tile, or slate). No wood shake — banned for cause in most California WUI areas.

2. No gaps at the roof edge, ridge, or where two roof planes meet — birds, leaves, and embers all use the same gaps. Birdstop and metal flashing close them.

3. Gutters cleaned of needles and leaves; metal gutter guards installed where trees overhang. Plastic gutter guards melt in fire and clog faster than they help.

4. Skylights are tempered or dual-pane and screened. Old plastic skylight domes are an ignition risk on a long-roof flat plane.

5. Roof penetrations (plumbing vents, satellite mounts, antenna brackets) are properly flashed and sealed — open penetration points let embers into the attic.

6. Soffited (boxed-in) eaves — open eaves catch embers in the rafter bays. If you can't soffit, screen the rafter bay openings.

7. Every attic, crawlspace, gable, and dryer vent uses 1/8-inch noncombustible mesh or a WUI-listed ember-resistant vent. See our ember-resistant vents guide for the full procedure.

8. Foundation and crawlspace vents are screened — these are the most-forgotten openings on the house.

9. No stored cardboard, fabric, or solvents in the attic directly under a vent. Radiant heat through mesh can still ignite nearby fuel.

10. Noncombustible siding (fiber cement, stucco, metal, brick, stone) — or at minimum ignition-resistant. Vinyl and untreated wood are the worst performers.

11. No gaps where siding meets the foundation, eaves, windows, or doors. Caulk, flashing, and weatherstripping close ember pathways.

12. Dual-pane windows with at least one tempered pane. Single-pane glass cracks from radiant heat and lets embers in. Tempered glass roughly doubles the time the window survives.

13. Solid-core or metal exterior doors with weatherstripping that closes gaps. Hollow-core doors burn through quickly.

14. Garage door sealed at the bottom with a noncombustible threshold seal — embers blow under standard garage doors and find paint, gas cans, and cardboard.

15. Pet doors closed, latched, or weather-sealed during high-fire conditions.

16. Composite or noncombustible deck boards, or 1-inch-plus solid wood. No gaps where leaves can pack underneath.

17. Underside of the deck is screened with 1/8-inch metal mesh, and is clear of stored fuel (firewood, paint, cushions).

18. The 5 feet of fence closest to the house is metal, not wood. A wood fence touching siding is a fuse leading flame to the wall.

19. Gates between fenced yards and the house are metal where they connect to the structure.

20. Sheds and detached garages within 30 feet are hardened to the same standard as the house — Class A roof, screened vents, noncombustible base.

21. Zone 0 (0–5 ft): noncombustible only — gravel, pavers, hardscape. No mulch, no shrubs against siding, no firewood, no wood fence connections.

22. Zone 1 (5–30 ft): irrigated, well-spaced low plants. Trees pruned 6–10 ft up. No dead material. No continuous shrub bed.

23. Zone 2 (30–100 ft): thinned trees and shrubs (10+ ft canopy separation), no ladder fuels, grass kept short.

24. Firewood is stored at least 30 ft from any structure, ideally uphill so any fire in it moves away from the house.

25. Propane tanks have a 10-ft clear, noncombustible perimeter and are not screened by vegetation.

26. Address is visible from the road at night (reflective numbers, 4 inches minimum). Firefighters can't defend what they can't find.

27. Driveway is at least 12 ft wide with overhead clearance, allowing a fire engine to enter and turn around.

28. A water source (pool, hydrant, or storage tank with a fire-department-thread connection) is accessible on the property where feasible.

29. Power shutoff and main gas shutoff are accessible, labeled, and known to everyone in the household.

Don't try to do all 29 in a weekend. Start with the items that move your wildfire risk score the most for the least money:

Clean your roof and gutters this Saturday. Walk your Zone 0 with a notebook. Replace 1/4-inch vent mesh with 1/8-inch. Those three projects routinely move FireScores grades by 15–25 points and cost under $200 in materials.

Then plan the medium-cost items over a season: ember-resistant vents on the most exposed walls, dual-pane window upgrades on the wildland-facing side, a metal Zone-0 fence section where wood currently meets siding.

Save the big items (Class A re-roof, full siding replacement) for the natural replacement cycle. The point of the checklist is to do every project at the right time — not all at once.