Hyload Jamb Closure Membrane for Flashing

The Hyload Jamb Closure Membrane is an 8” or 12” poly-reinforced membrane, incorporating DuPont’s Elvaloy® KEE polymer (40 mils) and 4” of rubberized asphalt (15 mils) with a silicone release paper.
Tech Data PDF

Product Highlights

  1. The Hyload Jamb Closure Membrane is a tough watertight sheet membrane that provides closure between air and vapor barriers and windows.
  2. The Jamb Closure Membrane can be used in residential, commercial and industrial applications. Recommended to adhere all Hyload membrane systems
  3. Not effected by high alkaline environments typical of masonry construction
  4. Hyload Systems will not deteriorate or harden with longevity or ultra violet ray exposure
  5. Hyload’s Technical Service Department offers specialized advice through a highly experienced technical staff to aid the construction process.
  6. Hyload provides architectural design service, contractor training and job site assistance
  7. Lifetime Building Warranty available when total Hyload flashing system is used.

Flashing Applications and Packaging


  • Through-Wall Masonry Flashing
  • Door Jam Flashing
  • Window Jam Flashing
  • In conjunction with Hyload Pre-Formed Shapes
  • Building Envelope Flashing


  • Standard Widths:
  • 8” x 75’ and 12” x75’ Rolls


  • Black
  • Gray
  • Tan


Substrates and Performance Properties

  • ALL Hyload Membranes.
  • Wood
  • Metal
  • Concrete, Block, and Masonry
  • Stainless Steel

Performance Properties

ElongationASTM D412175%
Tensile StrengthASTM D412650 lbs/in2
Tear StrengthASTM D624280 ppi
Low Temperature FlexibilityASTM D1460 Pass
Water AbsorptionASTM D471Less than 0.1%

Limitations and Warranty

  • Hyload Jamb Closure Membrane should not be applied to moist or damp surfaces.
  • Hyload Jamb Closure Membrane should only be applied when both air and surface temperatures are 32°F and rising.
  • Hyload Jamb Closure Membrane cannot be used with coal tar mastic or polysulfide sealant.


Hyload makes available to its customers several high performance product warranties.  Contact Hyload’s Corporate Office directly for details. A standard warranty is 10 years.