Guide to Low-Slope Roofing
Learn the alphabet soup of materials, but first get the slope and underlying details right.
A good low-slope roof (3-in-12 pitch or lower according to the National Roofing Contractor’s Association, or NRCA)—rarely gets any attention. A bad one brings the kind of attention nobody wants. I see a lot of bad low-slope roofs and don’t know which is more astonishing: how little additional effort would have been required to build it right, or the extraordinary cost of correcting the roof and repairing the associated damage.
Karen L. Warseck, AIA, president of Building Diagnostics Associates, a Florida-based firm that specializes in identifying and fixing building-envelope problems, identifies the causes of roof failures in an Architect magazine article titled, “When It Leaks, It Pours”: “Normally we find that it’s about 60% to 70% construction, 20% to 25% design, and 10% materials.” In short, the roof is the wrong place to try to save money.
Though Warseck’s experience proves that the skill of the workers and the quality of…