Underlayment for Metal Roofing

Underlayment products for use beneath standing seam metal roof systems should be carefully selected to provide a roof system that performs optimally throughout the life of the building. Several considerations must be addressed in the roofing system design, including ensuring that the four barriers needed in any building enclosure i.e., water barrier, thermal insulation barrier, vapor retarder, and air barrier are provided and are in the correct location for a given climate.