What is ice & water barrier for?

Ice & Water Shield offers premium leak protection for sloped roofs in climates subject to ice dams and wind-driven rain. It is applied to the roof deck prior to the application of the finished roof covering, which is most often shingles but can also be tile or metal. The membrane goes under shingles and seals around nails that hold the shingles in place, so water that doesn’t drain properly cannot penetrate the roof. It also creates a weather-tight barrier against wind-driven rains that cause shingles to lift and leak. Affordable and easy to install, it provides added peace of mind for many years, even in the most brutal winters.