- Q. Is it true that the steeper a roof is, the longer it will last?
A.Yes, the steeper the roof, the longer the roofing material will last. Because water runs off the roof more easily, the roof covering will dry faster. And during the hottest part of the year when the sun is higher overhead, a steeper roof will absorb less solar radiation than a flatter roof. There are limits, however, since some materials will not be heavy enough or the adhesive strong enough to hold the roofing material on very steep roofs, such as those greater than 20/12. Fortunately, not a lot of designs call for such slopes.