Galvanized metal roofing (zinc coated) is common in commercial building and especially susceptible to corrosion. In any climate, moisture can build up under the roof and cause damage to the structure. WaterWay mats can be incorporated as a spacer between the metal and roof sheathing providing a passage for moisture drainage while reducing water accumulation which causes corrosion. In cold weather, a cold roof surface is desirable to prevent the build-up of ice and the problems associated with ice dam backup. WaterWay mats create a thermal break and ventilation layer in the roof where the conduction of heat would normally occur. This characteristic reduces the potential for ice dams.