The Sweat Equity column in the San Francisco Chronicle today steered readers to a UC PowerPoint presentation on the Web that provides details on fire-resistance ratings for roofs.
Produced by UC Cooperative Extension wood durability advisor Steven Quarles, the 18-slide presentation gives viewers an understanding of how roof coverings get their fire rating.
The information in Sweat Equity, a regular home improvement column written by brothers Bill and Kevin Burnett, was prompted by a reader question about whether an existing shake roof can be treated for improved fire resistance. In short, the answer is no.
Roofing systems are fire-rated either A, B, C or not ratable, with A the highest rating, or most fire resistant, according to the article.
If homeowners wish to preserve the woodsy and casual appearance of a wood shake roof, the Burnetts said the existing shakes should be replaced with new fire-retardant pressure-treated wood shakes. Alone, the pressure-treated shakes result in a class-B roof covering; in conjunction with an underlying fire barrier material, such as this gypsum or fiberglass, the roof is class A.
For more information on improving homes' fire resistance, see Quarles' Homeowners Wildfire Mitigation Guide online.Attached Images:
