Which of the following is not typical of ice protection for asphalt shingle roof?

Which of the following is not typical of ice protection for asphalt shingle roof?

• A. A self adhering polymer modified bitumen sheet
• B. shall extend from the eaves edge to at least 24 inches inside the exterior wall linem
• C. 2 layers of underlayment cemented together
• D. 1 layer of 90lb hot mopped mineral surfaced membrane

Answer: (D)

Ice protection for asphalt shingles relies on a water-tight barrier installed at the eaves to prevent meltwater from seeping back under the shingles during ice dams. The standard approaches are a self-adhering polymer-modified bitumen sheet and, where required, an additional layer of underlayment (often two layers cemented together) extending up from the eaves to a specified distance inside the exterior wall line. A hot-mopped mineral-surfaced membrane, while used for built-up roofing on flat or low-slope roofs, isn’t a typical or practical choice for ice protection under pitched asphalt shingles, making it the not-typical option.

Ice protection for asphalt shingles relies on a water-tight barrier installed at the eaves to prevent meltwater from seeping back under the shingles during ice dams. The standard approaches are a self-adhering polymer-modified bitumen sheet and, where required, an additional layer of underlayment (often two layers cemented together) extending up from the eaves to a specified distance inside the exterior wall line. A hot-mopped mineral-surfaced membrane, while used for built-up roofing on flat or low-slope roofs, isn’t a typical or practical choice for ice protection under pitched asphalt shingles, making it the not-typical option.