Adhesives & Sealants
Tape
3M
$15-$50/roll

Flashing Tape for Waterproof Window and Door Protection

Flashing tape is a self-adhesive waterproof membrane sealing critical building joints where water intrusion is most likely. Applied around windows doors and deck ledger boards it creates an impenetrable barrier directing water away from the building structure.

Key Features

  • Self-adhesive application
  • Waterproof membrane
  • UV resistant surface
  • Stretchable and conformable
  • Aggressive permanent adhesive
  • Multiple width options

Specifications

Widths: 4 6 9 12 inches | Thickness: 20-40 mil | Adhesion: peel-and-stick | Temp range: -40F to 200F | UV exposure: up to 120 days | Material: butyl or rubberized asphalt

Best For

Window and door rough openings deck ledger board rim joist sealing roof-to-wall transitions and any joint vulnerable to water intrusion.

Compatible Materials

OSB
Plywood
House wrap
Concrete
Masonry
Treated lumber

Pros & Cons

Pros

  • ✓ Easy peel-and-stick
  • ✓ Permanent waterproof seal
  • ✓ Conforms to irregular surfaces
  • ✓ Critical moisture protection
  • ✓ Long UV tolerance

Cons

  • ✗ Expensive per linear foot
  • ✗ Difficult to reposition
  • ✗ Requires clean dry surface
  • ✗ Cold weather reduces adhesion
  • ✗ Adhesive can be messy

Installation Tips

Apply to clean dry surfaces above 25F. Start bottom work up overlapping 2 in. Stretch into corners and around openings. Press firmly with J-roller. Install sill flashing before window then jamb then head flashing last.

Frequently Asked Questions