Building Products for the Professional

TW Underlayment

A 40-mil thick flexible self-adhering rubberized asphalt sheet membrane with a polymer film on the surface and a removable treated release film on the adhesive side. Well suited for use as an underlayment where water penetration prevention is required including on metal roofs. Provides secondary protection against water penetration after installation of a metal roof system.

TW Underlayment

Limited Warranty
  • 5-year Product Limited Warranty
  • Rubberized asphalt
  • Textured polymer surface provides enhanced skid resistance
  • Self-adhesive and treated release film for easier installation
  • High temperature resistance up to 245°F
  • Can be left exposed for up to 120 days before application of finished roof
  • Roll size is 200 square feet. (39-3/8" x 61')

IMPORTANT: This product features a skid resistant and tear resistant surface. This feature does not serve as a substitute for following all proper fall protection procedures in accordance with OSHA regulatory requirements–including the use of personal fall protection devices when working on a roof. Applicator safety is of utmost importance.

TW Underlayment

Application Instructions

When fasteners penetrate the TW Underlayment membrane during installation, the metal roof system manufacturer's recommendations must be followed to assure watertight integrity at the fastener penetrations.

Data Sheets