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Follow all verified local emergency instructions for evacuation to help fire crews protect our communities. If a wildfire is approaching, follow these steps to minimize risk to yourself and property: Do not rely solely on emergency services.
Fires require fuel to spread, and any combustible materials, including vegetation, wooden fences, or sheds can serve as fuel. Once ignited, these materials can create a direct fire path toward a house. There can be both horizontal and vertical paths.
The roof protects the house from the elements. Its large surface area, however, makes it extremely vulnerable to embers during a fire. Specifically, debris can accumulate close to roof-wall intersections, edges, skylights, and vents, and ignite during a fire.
In attics and crawl spaces, vents provide air circulation to prevent moisture buildup while keeping rodents and small animals out. However, depending on the mesh size and type of screen, small materials may pass through vents and deposit in enclosures.
The eave overhang protects your home from rain and sun. Depending on design, it also can allow embers to enter through under-eave attic vents. With open-eave construction, gaps between the rafter tails and the blocking can be vulnerable to ember entry.
Decks can be ignited by wildfires via flame contact (usually from below) or ember attack (usually from above). Burning decks will expose the house to long-term flame impingement, which could ignite siding and eaves, and/or shatter windows.
There are two main concerns regarding the fire safety of exterior siding: penetration of flames through walls and stud cavities, and spreading of flames into the attic through the soffit/eave area.
Wildfires can spread from the outside to the inside of buildings when windows break. Glass, the most vulnerable part of the window, can break when exposed to extreme heat, either radiant or from flame contact, or when wind-blown debris impacts the window.
The accumulation of debris in gutters poses one of the greatest fire hazards for a building. In the event that embers ignite debris, such as leaves or pine needles, the resulting fire will directly expose the edge of the roof to flames.
Fencing can increase or decrease a building's vulnerability to wildfires depending on its material and location. Combustible fences may ignite from direct flame contact or from embers depending on their state and the nearby vegetation.
