Every winter, temperatures drop into single digits; in some parts of the U.S., severe temperature drops can last for weeks. Icicles on the edge of the roof may look pretty, but they are a warning sign that ice dams may be forming. When heat rises into an attic it warms the roof, except at the eaves. As snow melts on the roof, the water freezes on those cold eaves and ice forms along the eaves. Because the melting water can't drain to the eaves, it backs up under the shingles, creating an ice dam. This puts the roof at risk of leaking.
In parts of the country where winter temperatures endure, it is essential to select a quality, durable roofing underlayment that can withstand long-term winter abuse. Installing inferior underlayment puts a roof at greater risk of failure from ice dams that have the potential to inflict serious damage to a home’s interior. Atlas WeatherMaster Granular SE can help prevent ice dams from forming.