Category: ROOFING

Manufacturing standards, minimum slopes, permitted underlayment materials, and installation requirements for roofing materials are specified by building codes. The codes also regulate a roof’s required level of resistance to flame spread and fire penetration, tested according to standards ASTM E108 or UL 790 and rated as Class A, B, or C roof coverings (listed here in decreasing…

Cool Roofs Roofs are exposed to solar radiation daily, and as that radiation is absorbed and converted to heat, the temperature of the roof covering rises. Depending on the intensity of the radiation and the portion of it retained by the covering, roof surfaces may routinely reach temperatures of 150 degrees Fahrenheit (65°C) or higher.…

Roofs with a pitch of 2:12 (17 percent) or greater are referred to as “steep” roofs. Roof coverings for steep roofs fall into three general categories: thatch, shingles, and architectural sheet metal. Thatch, an attractive and effective roofing, consisting of bundles of reeds, grasses, or leaves (Figures 16.1 and 16.2), is highly labor-intensive and is rarely used today.…

A low-slope roof (often referred to, inaccurately, as a “flat” roof) is usually defined as one whose slope is less than 2:12, or 17 percent. A low-slope roof is a highly interactive assembly made up of multiple components. The roof deck is the structural surface that supports the roof. Thermal insulation is installed to slow the passage of heat…