Residents who make their homes more fire resistant can increase the home's chances of surviving a wildfire, even if fire fighters are not able to get there. Creating a defensible space around the home reduces the flammable vegetation that can ignite the home. Homes in wildland fires are most often ignited by flying embers landing on or blowing into the home by strong winds.
The most vulnerable part of a home is the roof since it is a surface on which flaming embers or flying branches can lodge. Wood shingle roofs are extremely flammable. The other vulnerable areas of the roof are the valleys and the gutters, where dry vegetation can lodge and provide a nest for embers.
The most important change a resident can make in their home is replacing a wood shingle roof with a Class A or Class A assembly fire resistant roof.
On the home itself, vents in the eaves, the roof and the foundation, often provide an opening for embers. Make sure all vents are covered with 1/16” wire mesh to keep embers from being blown in by strong winds and igniting the attic or the crawl space.
Heat Traps Under Eaves and Decks
When a fire burns up a hill under a deck, the heat is trapped and then begins to preheat the wood above it and eventually ignites it. The same process can happen under eaves. Box in decks and eaves with fire resistant material so the flames cannot get under them. At a minimum, enclose them with 1/16” wire mesh and remove all flammable materials from under them.
Windows and Siding
Fire spreads three ways; direct flame impingement; by flaming embers or debris blown by wind; and through radiant heat. Radiant heat can ignite a structure without flames ever touching it. Often the radiant heat from nearby flaming trees can melt or crack windows. Once this happens, embers can be blown in and ignite the home from inside. If possible, replace all windows with triple glazed windows with tempered glass on exterior.
Wood shingle siding is much more likely to ignite than other types of sidings. If possible, replace it with ignition resistant siding. If replacing the windows or siding is not possible, make sure to remove all fire prone vegetation from 30’ to 100’ to reduce the risk of ignition through radiant heat.
Download the One-Time Fire Safe Checklist for a list of one-time changes residents can make to their home and yard to reduce the risk of catastrophic fire.