Self-Adhered Roofing Membrane

A self-adhered membrane, often called "peel-and-stick", is a roofing or underlayment sheet whose bonding adhesive is applied in the factory and protected by a removable release liner. The installer positions the roll, peels away the liner and presses the sheet into place, usually with a weighted roller. Laps may be self-sealing or may use a separate adhesive strip.

Types

• Modified bitumen: SBS base sheets and cap sheets with a self-adhesive rubberised bitumen underside. Some systems are fully self-adhered; others use a self-adhered base under a torched or hot-air-welded cap.
• Single-ply: TPO, PVC and EPDM sheets are available with factory adhesive backings.
• Flashings and accessories: peel-and-stick flashing strips, cover tapes and patches are widely used with EPDM and other systems.

Advantages

• no open flame, kettle or wet adhesive
• low odour, suitable for occupied buildings
• consistent bond quality because the adhesive is factory-controlled
• faster detailing; EPDM industry sources credit factory tape products with improving flashing quality

Limitations

Self-adhered products depend on clean, dry, primed substrates and on adequate temperature; adhesion falls off in cold weather. Some single-ply peel-and-stick products are more weather-sensitive during installation than welded or mechanically fastened systems, and their long-term performance record is shorter than older methods.

Uses beyond roofing

Self-adhered rubberised bitumen sheets also serve as temporary roofs, vapour retarders, air barriers and ice-barrier underlayments on steep roofs.

Historical context

Self-adhesive technology built on earlier advances in factory-applied tapes. In EPDM roofing, factory seam tapes replaced liquid seam adhesives during the 1980s and were followed by self-adhering flashing components with factory-applied adhesive, both credited with reducing reliance on site workmanship.