Wildfire Season Roof Protection Guide — Harden Your Home Against Embers

Roofing materials are classified by fire resistance: Class A (highest — concrete tile, clay tile, metal, slate, and Class A–rated asphalt shingles), Class B (moderate), and Class C (minimal). Untreated wood shakes are unrated and extremely dangerous in wildfire zones. If your roof is wood shake without fire treatment, replacing it with Class A material is the single most impactful home-hardening action you can take. Many fire-prone jurisdictions now require Class A roofing on new construction and re-roofs.

Burning embers as small as a dime can ignite a home if they reach combustible material through a gap. Install 1/8-inch metal mesh screens over all attic vents (soffit vents, gable vents, ridge vents, and turbine vents). Seal gaps at roof-to-wall junctions, where eaves meet walls, and around chimney chases. Commercial ember-resistant vent covers ($15–$50 each) are designed specifically for wildfire protection and meet California Chapter 7A requirements.

Dry leaves, pine needles, and organic debris on the roof are fuel for embers. A single ember landing in a gutter full of dry leaves can ignite the gutter contents, which then ignites the fascia and eave. Clean the entire roof surface, all gutters, all valleys, and behind all penetrations (chimneys, skylights, dormers). Remove any moss or lichen — while not immediately flammable, they dry out during fire season and become tinder. This cleaning is the most time-effective wildfire preparation you can do.

Plastic and vinyl gutters melt and ignite easily. Metal gutters (aluminum, steel, or copper) resist ember ignition. If you have metal gutters, install metal gutter guards to prevent debris accumulation — a gutter guard that's also ember-resistant gives you both maintenance reduction and fire protection. If you have vinyl gutters in a wildfire zone, replacing them with aluminum is a worthwhile investment ($5–$15 per linear foot installed).

Even with gutter guards, some fine debris (pine needles, pollen, seed husks) accumulates on the roof surface and in gutters. During active fire season, check and clear debris monthly. Pay special attention to valleys, behind chimneys, and where dormer walls meet the main roof — these areas collect windblown debris that dries quickly in summer heat. A 30-minute monthly clearing eliminates the fuel that embers need to ignite your roof.

The first 5 feet from your home's exterior is the most critical fire protection zone. Remove all vegetation, mulch, and combustible storage from this zone. Replace organic mulch with gravel, stone, or decomposed granite. Move firewood stacks, lumber, and propane tanks at least 30 feet from the house. This noncombustible buffer prevents ground fire from transitioning to your structure — even if fire reaches your yard, the ember-resistant roof and noncombustible buffer zone give your home a fighting chance.

Overhanging branches provide a direct fire path from ground vegetation to your roof. Maintain at least 10 feet of clearance between tree branches and the roof surface, and remove any branches within 10 feet of chimney openings. Trim lower branches up to 6–10 feet from the ground on trees within 30 feet of the house to reduce the likelihood of ground fire 'laddering' into the tree crown. Dead branches at any distance should be removed entirely.

Your chimney spark arrestor prevents burning embers from exiting through the chimney (outgoing fire risk) and prevents external embers from entering through the chimney (incoming fire risk during wildfire). Check the spark arrestor screen from the ground with binoculars — look for rust holes, torn mesh, or displaced caps. The screen should have openings no larger than 1/2 inch. Replace corroded or damaged screens immediately during fire season.

A sealed structure prevents ember entry and reduces the oxygen available to feed interior ignition. Close all windows and exterior doors. Close fireplace dampers. If you have time, seal pet doors and mail slots with fire-resistant tape. Turn off the HVAC system so it doesn't draw smoke and embers inside through the ventilation system. Leave interior doors open so firefighters can move through the house if they enter to suppress spot fires.

A wet roof is significantly more resistant to ember ignition than a dry one. If fire is approaching but not imminent, spray down the roof, gutters, and the first 5 feet of ground around the house. Do not remain to continue wetting if evacuation orders are issued — your life is more valuable than the house. Leave ladder access set up against the house for firefighters. Move garbage cans and other combustibles away from the house if time permits.

Every wildfire season, homeowners die trying to defend properties or delaying evacuation for 'one more task.' Fire conditions can change from manageable to unsurvivable in minutes when wind shifts. When evacuation is ordered: leave. Take your go-bag, family, and pets. Drive with headlights on and windows closed through smoke. If your roof and defensible space are properly prepared, your home has the best chance of surviving without you there. If they're not prepared, staying won't save it.