ASTM E331

ASTM E331 is a standard test method used to evaluate the ability of building materials, particularly roofing, siding, and window assemblies, to resist water penetration when exposed to wind-driven rain. It involves simulating rain and wind conditions to see if water leaks through the building elements. This helps ensure that structures are durable and can protect against water damage, which is vital for safety, comfort, and longevity. By following this standard, manufacturers and builders can demonstrate that their products perform reliably under realistic weather conditions.