Homes threatened by wildfire are primarily those located in the "wildland-urban interface". This is the zone, specifically along the Lake Michigan Beach area, where homes and subdivisions have been located in wildland areas where natural wildfires can have an impact. While wildfires in themselves are not bad, they burn whatever fuel is in their path, whether it is vegetation or buildings. Wildfire can destroy or damage a home in many ways although any home can be protected by applying simple practices. The Firewise Communities/USA Program was developed to help homeowners understand wildfire behavior and how to protect their home should a wildfire occur.
One of the most common causes of a home being damaged or destroyed is due to radiant heat. In a wildfire, radiant heat is the heat given off by burning vegetation. The high temperatures of some wildfires can cause the deck, siding or roof of a home to ignite, just because the fire was too near the home. Especially in areas of solid conifers (pines, spruces, junipers, and other conifers), radiant heat can be very hot. Studies have shown that when solid stands of conifers exist, a minimum of 30 feet of "defensible space" should be provided between the vegetation and the home. Studies in western wildfires have shown that approximately 85 percent of those homes surviving a major wildfire had 30-50 feet of defensible space around the home, coupled with fire-resistant roofing.
Another important cause of homes and buildings catching fire during a wildfire is fire brands. Fire brands are the burning embers that rise out of a vegetative fire. This is similar to those one might see rising out of a campfire. However, in a wildfire, these fire brands can act like a blizzard with glowing embers swept along on wind currents and landing on or under decks, on roofs, in wood piles and other locations where a new fire could start. Fire brands can also be carried up to a mile downwind from the actual fire, starting spot fires ahead of the original fire.
Studies have shown that by using fire-resistant roofing such as metal, asphalt, or composite shingles can prevent or reduce a roof from catching fire. Keeping leaves and litter from gathering under decks, behind landscape plants, or out of eave trough gutters can greatly reduce the chance of a house or building catching fire.
The following link provides additional wildfire mitigation information that will be useful to local jurisdictions and homeowners in the wildland-urban interface.