Waterproof Flashing

Waterproof Flashing

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FortiFlash® is engineered to deliver lasting protection against water intrusion in the most demanding environmental conditions. It is the premium self-adhesive waterproof flashing membrane for windows. It is also ideally suited for flashing non-roofing horizontal conditions such as pot shelves, parapets, sill pans and recessed windows. Its strong adhesion makes it a perfect choice for sealing around common through-wall penetrations such as hose bibs, vents, electrical boxes and exterior lights. Yet, its price makes FortiFlash the price/performance solution for the most challenging construction requirements.

Reinforced by a strong cross-laminated high-density polyethylene film, FortiFlash can be installed around protrusions and into the tightest corners without delaminating or tearing. Its self-sealing rubberized asphalt core stays in place in the most punishing weather conditions. Available in 25 and 40 mil versions, there is a FortiFlash designed to fit your needs.

Part of the Fortifiber® 1-2-3 moisture control system, FortiFlash is designed to withstand the rigors of the jobsite and the elements, and is backed by an industry-leading 15-year warranty.


  • Maximum water and leak protection
  • Self-adhesive installation
  • Self-seals around fasteners
  • Exceeds ASTM & AAMA standards
  • Part of a complete moisture control system
  • For best results, use with Moisture stop sealant and liquid flashing