The radiant heat from flames that are within the first 5 feet of the home can break the glass in a window and penetrate into the interior of a home. Having a dual-pane, tempered glass window offers the best protection because tempered glass does a much better job resisting breakage and even if the outer-pane of glass breaks, the inner pane may remain intact.
Siding is an expensive element of any home, and many types of siding are combustible. If the siding on your home is combustible it is vulnerable to direct flame contact and radiant heat exposure, and therefore it is important to keep the area within 5 ft. of your home free of combustible items, plants, and debris that could catch fire and brings flames dangerously close to the siding. Once ignited, flames from burning siding can encroach on windows and eaves – potentially endangering the entire house.