FS500HTLeakBarrier® FS500HT is a premium, non-reinforced roofing underlayment comprising specially formulated rubberized asphaltic adhesive and surfaced with a cross laminated HDPE film structure that is uniquely treated to provide enhanced skid resistance. The rubberized asphalt-based adhesive withstands high temperature conditions up to 250°F and self-seals around nails


LeakBarrier® FS500HT is a premium ice & water shield designed to prevent leaks caused by ice and water damming and wind-driven rain. It is highly effective in critical roofing areas such as valleys, ridges, coping joints, chimneys, vents, dormers, skylights, and other flashing areas, and is well suited for use in metal and mechanically fastened tile roof systems.

Features and Benefits

  • Dual Protection: Rubberized asphalt and polyolefinic film laminate form two distinct water barriers
  • Self-Sealing: Rubberized asphalt self-seals around nails
  • High Temperature Resistant: Withstands temperatures to 250°F
  • Exceptional Durability: High tensile and tear strengths
  • Excellent Walkability: Anti-skid treatment on the film surface provides good traction
  • Instant Watertight laps: Self-adhesive coating on the side lap for immediate bond
  • Versatile: Adheres to a wide variety of substrates
  • Easy to Handle: Very pliable and easy to install
  • Aesthetically Pleasing: White colored film provides cooler working surface
  • Superior UV Resistance: Surface stays intact when exposed to the elements
  • Extended Exposure Time: Can be left exposed for up to 180 days


  • LeakBarrier FS500HT must be stored indoors, in a dry location.
  • Store boxes on end only. Do not store in a leaning position.
  • FS500HT must be protected from the elements. Do not store product in direct sunlight.
  • Store FS500HT at room temperature. Prolonged exposure to elevated temperatures may reduce the adhesive characteristic of the material.

General Precautions

  • Install material in strict compliance with applicable Building Code.
  • Follow Occupational Safety and Health Administration (OSHA) safety standards; use common sense measures and adequate precautions to prevent accidents.
  • Install FS500HT only when material interface temperatures (air, deck, material) are 40°F and rising.
  • Do not install when any form of moisture such as water, ice, snow, dew, rain, etc. is present.
  • Ensure roof has positive drainage prior to installation.
  • Ensure proper ventilation of the attic.
  • Do not use FS500HT as the primary weather resistant roof covering.
  • Do not apply over existing roofing material.
  • Not recommended for extreme high temperature environments such as under copper or zinc metal roofing.
  • FS500HT must be covered with a finished roof covering within the specified exposure time of the product. Refer to section on Features and Benefits for exposure time.

Surface Preparation

  • The substrate shall be clean and dry prior to installing FS500HT.
  • For re-roofing, all old roofing and other loose material must be removed prior to installation.
  • Acceptable substrates for adhesion of LeakBarrier membranes can be found at the Tarco website.
  • For best results, surface may be primed with an ASTM D41 primer prior to installation of FS500HT. When primer is used, ensure the primer is fully dry prior to application of FS500HT.

Application Guidelines

  • Cut the FS500HT roll to suitable, manageable lengths before installation.
  • Place a full width piece of the sheet parallel to the eave (low) edge of the roof.
  • Align the sheet so as to eliminate wrinkles and keep the sheet even with the eave edge.
  • Fold back the sheet and remove the exposed release liner.
  • Working from the center out, roll the sheet on to the substrate, taking care to avoid wrinkles and ridges.
  • Sheet must be set straight. Repeat this process for the other half of the sheet.
  • Apply the next eave course in the same manner, overlapping the first course at the end lap by 6'.
  • Align the next roll over the preceding sheet so as to form a minimum 3.5" side lap and 6" end lap or as per applicable Building Code. Then install sheet, as instructions above.
  • Stagger the end laps a minimum of 36" (3') from the preceding course.
  • In steep slope applications where backnailing is required, ensure all nails are covered by the subsequent sheet.
  • Apply subsequent courses in the same pattern and technique over the preceding sheets.
  • When applying material in valleys, start at the low point and work to the high point.
  • Roll the entire membrane surface, paying special attention to side laps, end laps and T-joints. Roller weight shall be 70 lb. minimum for low slope (≤2:12 pitch) and 28 lb. minimum for steep slope (>2:12 pitch).


Property Typical Value Reference Test
Thickness 40 mil (1.0 mm) ASTM D1970
Tensile Strength 400 psi ASTM D412 (Die C)
Elongation, Rubberized Asphalt >300% ASTM D412 (Die C)
Adhesion to plywood at 40°F 4 lbs/ft of width ASTM D903
Adhesion to plywood at 75°F 20 lbs/ft of width ASTM D903
Flexibility temperature -22°F ASTM D1970
Tear resistance 30 lbf ASTM D1970
Slip resistance Pass ASTM D1970
Nail sealability Pass ASTM D1970
Waterproof integrity of lap seams Pass ASTM D1970
Compound stability 250°F ASTM D5147
Moisture vapor permeability 0.05 U. S. Perm or Less ASTM E96

Product Data

Width 36 in
Length 66 ft 8 in
Gross Coverage 2 squares
Weight 55 lbs. (nominal)
Thickness 40 mil (nominal)


Tarco Specialty Products, Inc. offers a 30 year Limited Warranty.

Quick Reference Product Guide

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