Location Of The Structure
Location location, location.  Where your home is situated plays a large part into how susceptible it is to wildfire.  Ideally, structures should be located at least 30 feet from property boundaries so the owner may maintain control of potential hazards on all sides of the structure.  Additionally, structures should be constructed away from steep slopes to avoid being superheated by fire from below.

Materials Used In Construction
Careful consideration should be given to the types of construction materials used when building in the wildland/urban interface. Some materials have a much greater susceptibility to ignition from wildland fires than others. The following is a list of construction alternatives that will minimize your risk:

Roofs - Roofs are highly susceptible to firebrands. Roofs should be covered with nonflammable materials. Wood shake roofs are a major cause of home-loss due to their extreme susceptibility to firebrands.  Some roofing alternatives include tile, metal, or fiberglass materials that will not burn.

Walls - Walls are highly susceptible to radiation and convection ignition. Constructing your walls with flame resistant materials will minimize the likelihood of your walls catching on fire. Flame resistant materials include cement, plaster, stucco, and concrete masonry. Other non-burning materials such as vinyl may not catch on fire but might melt away during exposure to high heat and expose interior walls to potential ignition.

Windows - Using tempered glass will reduce the chances of the window breaking and allowing firebrands and flames inside. This is especially important on the sides of the house that face slopes or have vegetation near.

Eaves and Overhangs - Bay windows and room push-outs are often found facing slopes. Unfortunately, these features are very susceptible to convective exposure. It is essential to use non-flammable materials in their construction when possible and eliminate any rough edges that can trap firebrands.

Vents - To further reduce the risk of ignition by firebrands, vents should be constructed to prevent passage of objects larger than ¼ inch, and should be constructed of materials that will not melt or burn when exposed to high temperatures.

Attachments - Additional structures, such as woodsheds connected to the main building, are considered part of the structure when determining the susceptibility of ignition to the main building. They should therefore either be built out of non-flammable materials or built a safe distance away from the main structure.

For more information on building material alternatives, consult your contractor or contact your homeowner’s insurance agent.

Other Structural Considerations
In addition to location and materials, additional considerations should be given to the density of structures in a certain area, proximity to slopes, and the local fire history in the area.

Structure Density - The number of structures within a given area determines structure density. Structure density often affects the overall exposure, spread, and intensity of wildland fires. However, structure density is often out of homeowners’ control and needs to be considered by the land developer.

Slopes - When possible, build your home away from slopes. Slopes increase your home’s susceptibility to ignition by increasing its exposure to both convective and radiant heat.

Local Fire Occurrence - Looking at the local fire history can often allow a homeowner a reasonable way to predict local fire occurrence.  Areas that have had fires in the past often have them again.  This may be an area of high traffic, where people-caused fires occur, or geographically, where intense lightning activity occurs.
 

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