Altaron Synthetic Roofing Underlayment

Class W1 indicates that the underlay has passed a water penetration test at a defined hydrostatic pressure, confirming its ability to resist liquid water ingress under typical roofing conditions. Higher classes (W2, W3) correspond to higher pressure resistance, while W1 is commonly specified for standard synthetic roofing underlay applications.

The 12-week outdoor weathering rating indicates that the underlay can remain exposed to sunlight, rain, and temperature variations for up to 12 weeks without significant degradation of its mechanical or protective properties. This allows for flexibility in construction scheduling, especially during phased roofing projects.

Yes, the synthetic underlay is suitable for use under tiles, shingles, slate, metal roofing, and other common roof coverings. It provides a weather-resistant barrier that helps protect the roof deck during and after installation. However, compatibility with specific roofing materials should be confirmed for optimal performance.

Class E is a reaction-to-fire classification that indicates the material's performance when exposed to fire. It does not denote a fire-resistant barrier but provides a defined level of reaction-to-fire performance. The underlay should be used as part of a complete roof system designed to meet local building regulations.