How homes can be designed, built and maintained to withstand a wildfire.
For homes in the wildland/urban interface, primary ignition sources are: flames (that can be up to 3 times the height of the vegetation), radiant heat and airborne firebrands, however, homes can be designed, built and maintained to withstand a wildfire even in the absence of firefighters. Vulnerable areas include the roof, soffits and windows.
Wood shake and wood shingle roofs (although not common in Florida) are a special hazard. These roofs will quickly ignite when exposed to flames or firebrands. A wood shake or wood shingle roof also increases the chance that the fire will spread to other structures by producing airborne flaming shingles that can travel with the wind and land on other flammable surfaces. Recommended roofing materials include: Class A asphalt/fiberglass shingles, sheet metal, terra-cotta tile and concrete. Roofs should be kept free of leaves and other debris.
Construction materials such as vinyl soffits have a greater potential for damage from wildfire than fire-resistant building materials. Vinyl soffits will soften when exposed to heat or flames from a wildfire and fall away from the roof trusses. When this occurs, windblown embers (fire brands) can enter the attic area and ignite the ceiling and/or roof. Installation of metal screening or hardware cloth under vinyl soffits has been recommended as a way to preserve the structural integrity of the soffits exposed to heat or flame. For maximum fire safety, soffits should be made of non-combustible material or (minimum) ½-inch nominal wood sheathing.
For homes in the wildland/urban interface, windows and skylights can be critical entry points for wildfire. Radiant heat can break large windows, allowing firebrands to enter the structure. Large, single-pane windows are particularly susceptible. Smaller windows with double-paned glass (better) or tempered glass (best) are more fire resistant.