For a roof to last, your roofing system must include protection from wind-driven rain. This is accomplished by installing waterproofing underlayment directly beneath the shingles. WeatherLock® Series self-adhesive water-proofing underlayment is perfect for both new construction and reroofing projects. In addition to protecting the roof deck from damage from ice dams and wind-driven rain, WeatherLock should also be used on areas of the roof where water has a tendency to collect or flow. Valleys, vents, chimneys and skylights are examples of where WeatherLock Series underlayment should be considered.