In a typical home, there’s about a hundred feet of space between the house and any conflagration heading towards it. Experts call this “defensible space”, where there must be less fuel for the fire to burn to buy the home some time, if not protect it. Yes, fiber cement siding in St. Paul has been shown to resist fires, but there’s no such thing as being too safe.
Besides, burning fuel isn’t the only way for fires to spread. Embers can drift from the inferno to as close as the defensible space depending on its distance. If debris like dry leaves on the roof catch fire, fiber cement won’t be able to stop danger from above. In the end, fiber cement siding is only part of a wider safety strategy.
The first 70 feet or extensive zone engages the incoming fire by providing less fuel to burn. Keep in mind that fire dies if it’s robbed of one of three key elements: fuel, oxygen, and heat. In some states such as Minnesota, it can extend to up to 200 feet from the house.
If the fire breaches the extensive zone, the remaining 30 feet or intensive zone has even lesser fuel for the fire. Ideally, this portion of the space should be almost devoid of any trees; only the trimmed grass should stand between the house and flame. However, homes with noncombustible siding such as fiber cement can have plants within five feet of the house.
Those who didn’t adapt this strategy learned the hard way. In a survey by the Washington-based Pacific Biodiversity Institute, most homes close to Yarnell, AZ were heavily wooded; nine out of ten. It became the site of a devastating fire in June, 2013; more than a hundred buildings were destroyed, most of them the heavily-wooded homes.
Defensible space can also prove useful if your siding sustained damage for some reason. If St. Paul siding repair by companies like Twin Cities Siding and Roofing will take some time, 100 feet will be enough to buy you some time.
(Article image and excerpt from “Defensible Space in Wildfire-Prone Areas Can Save Lives—So Why Isn’t it the Norm?” KCET, July 22, 2013)