Tyvek® FlexWrap™~ NF addresses the issues of flashing vulnerable bottom corners of the sill where water damage is most likely to occur.

Tyvek® FlexWrap™ NF is a conformable, self-adhesive flashing solution for sills and non-straight portions of windows, doors and other wall penetrations.

Tyvek® FlexWrap™ NF is a premium performance, extendable self-adhered flashing material that can be applied over a wide range of building substances, including non-nailable sheathing materials like PS foam board, fiberboard, concrete masonry unit (CMU) and other such materials. Unlike competitive products, Tyvek® FlexWrap™ NF does not require the use of mechanical fasteners in the flexed corner areas.

Tyvek® FlexWrap™ NF also flashes round-top or custom-shaped windows in a seamless manner, eliminating the need to cut and place individual pieces of conventional flashing on an arched opening.


Superior protection from water damage

  • Helps seal the building envelope when used with DuPont Building Envelope Systems products
  • Meets the AAMA 711-13 material standard at the highest classification level: Class A (no primer) and Level 3 Thermal Exposure (80’C / 176’F for seven days)
  • Meets and Exceeds ASTM E331 Standard Test Method for Water Penetration of Exterior Windows, Skylights, Doors, and Curtain Walls by Uniform Static
  • Air Pressure Difference: no leakage at 300 Pa (equivalent to 50 mph wind load), even after thermal ageing (0-120’F)
  • Does not contain asphaltic / bitumen adhesive materials which many window manufacturers prohibit due to adverse material reactions, such as black staining, oozing, and deformation over time, particularly with vinyl flanges.
  • Can be installed at external temperatures as low as -4’C (25’F) as long as the surface is clean and free from frost and ice

Easy installation

  • Packaged in ready-to-use 152mm x 22.9m and 228 x 22.9m rolls
  • Helps to facilitate the creation of airtight and watertight seals around windows, doors sills, chimney breasts, pipe penetrations, and any custom shapes

Superior durability

  • Extendable flashing constructed with a durable, microcreped Tyvek® FlexWrap™ top-sheet, a premium butyl adhesive layer, and a specially designed release liner
  • Designed to withstand up to 270 days of UV exposure

Excellent adhesion performance

  • 100% butyl adhesive performs through extreme temperatures
  • Adheres to most common building materials