Narrator: The raging wildfires that struck southern California in fall 2007 destroyed about 1500 homes. In some heavily-damaged areas, flames seemed to leapfrog through neighborhoods - leaving some homes unscathed alongside those that were reduced to ashes. University of California scientists have found that is not an entirely random phenomenon. Stephen Quarles, a UC Cooperative Extension wood durability advisor says there's a lot homeowners can do to protect their homes from a wildfire. During a fire demonstration, Quarles explained that there is a general perception that composite materials are much more fire safe than solid wood.
Quarles: And that can be true, but as this demonstration shows, it's not always true and in this case, the wood/plastic composite material burned much more readily than the solid wood deck. And the solid wood deck put itself out actually after the ignition source burned out and the plastic composite material kept on burning actually. After less than an hour, it became a pretty big fire on the deck and this is another message that we'd like to give and in doing these demonstrations. And that is, usually a home that ignites in a wildfire - the fire that ultimately results in the loss of a house starts out as a pretty small fire. That small fire will get big and it takes time, but if that fire did get big and transferred to the siding or up the wall and maybe broken a window, there would be a number of ways that that fire could have ignited the house and then result in a loss of the house.
Narrator: Quarles identifies six priority areas for making changes to existing homes in fire hazard zones: the first priority is the roof; homeowners should upgrade to a non-combustible ‘Class A' roof; then there are vents - make sure there are crawl spaces under homes or attics; get rid of vegetation that's close to the home, under eaves or near windows - but bear in mind that trees and shrubs farther away can serve as buffers against radiation, convective heat and flying embers. Next, make sure windows are dual-pane with tempered glass. Finally there's decking and siding. The thicker the deck boards, the better. In research trials, good quality sheathing, which is installed underneath the siding was key to protecting the home's studs. For Science Today, I'm Larissa Branin.