Last month, I talked about fire behavior and how its travel and spread can be reduced around your home. We, the fire community, call this area of enhanced protection “Defensible Space.”
This week I want to explain how a wildfire spreads to a home or building in its path.
Reducing the amount of combustible vegetation immediately adjacent to and outward from the home gives firefighters and your house a chance that an approaching fire can be slowed or stopped. Often this is enough to reduce the possibility of it igniting.
During a wildfire that is moving toward structures, ignition of a building can occur in several ways. One way might be sparks, firebrands or embers, byproducts of burning material most often carried by the wind.
Sometimes these embers travel far ahead of the fire and can create new “spot fires” in areas of unburned brush or grass. These same embers can find their way into and onto your home. And those that still have wood-shingle roofs are most vulnerable. Things like your wicker furniture, a cloth umbrella, a pile of pine needles on your deck or patio and even that cocoa mat outside the front door we wipe our feet on are all potential ignition sources.
Homes built on elevated foundations with crawl spaces and most homes built with an attic space will have required vents that allow the circulation of air in these areas to prevent moisture-related problems. These vents come in various shapes and sizes and are typically covered with a screen material to keep rodents, birds and other larger pests out. Most of these vents will not stop burning embers from finding a way through.
Radiant heat is another common way wildfire can ignite a home. This is the heat the burning vegetation too close to the side of the house gives off. If exposed to this heat for a long enough duration, ignition of the building can occur.
The final method is through direct flame contact. In other words, the flames of the burning brush, trees or grass are in direct contact with the home or building. In this situation, defensible space and/or fire abatement work was probably nonexistent.
One of the most valuable resources available to homeowners is the Mountain Communities Fire Safe Council. Our staff can help to educate and guide homeowners through an evaluation of their property and how to prepare it and create their own defensible space. The hardening of your home and other preventative measures can be discussed.
In my next column, I will introduce our project manager, Pat Boss. I also will explain the financial assistance available to offset some of the costs toward abating your property.
