Why vents matter during a wildfire
Attic and crawl-space vents are necessary for building ventilation, but they can also become entry points for wind-driven embers. Once embers enter an attic or underfloor space, they can ignite combustible material that would otherwise be protected from direct flame.
What official wildfire guidance recommends
CAL FIRE Ready for Wildfire recommends noncombustible metal screening and identifies State Fire Marshal-approved flame- and ember-resistant vents as an enhanced protection option. California's State Fire Marshal also maintains listings of WUI products reviewed for applicable wildfire-building requirements.
Do they make a home fireproof?
No. Ember-resistant vents reduce one vulnerability; they do not eliminate wildfire risk. A home can still be threatened by roof ignition, combustible debris, windows, siding, decks, fences, direct flame contact and radiant heat.
Why a system approach is stronger
San Diego County's Wildfire Prepared Home guidance combines structure hardening with the area immediately around the home. That is a useful way to think about vent upgrades: as one part of a broader plan.
When vent upgrades may be especially worth reviewing
- Older or damaged vent screens
- Large or missing screening
- Combustible material stored near attic or crawl-space vents
- Homes undergoing a broader wildfire retrofit
- Projects where applicable wildfire construction requirements call for upgraded vents
Next steps
For product-selection factors, see how to choose ember-resistant vents. For project pricing, read our San Diego vent cost guide.