image of Platinum HT-SA Underlayment
image of Platinum HT-SA Underlayment
image of Platinum HT-SA Underlayment
image of Platinum HT-SA Underlayment

Product Sheet

Platinum HT-SA Underlayment

Introducing PLATINUM HT-SA our premium high temperature self- adhering roofing underlayment that combines the superior slip resistant GRIPSPOT technology developed by FT Synthetics with a high strength high temperature modified rubberized asphalt backing that has both low temperature (40°F / 4.4°C) deck adhesion, high temperature flow stability (240°F / 115°C) and a limited lifetime warranty. In addition, PLATINUM HT-SA has a split release silicone liner and a synthetic construction to inhibit mold growth.

PLATINUM HT-SA can be used in most types on installations whether they are commercial or residential. It can be used under metal, wood, asphalt & synthetic shingles, slate or tiles. PLATINUM HT-SA meets and exceeds required industry standards.


  • GRIPSPOT Technology for superior slip resistance
  • Silicone treated split release line
  • High temperature resistant to 240°F (115°C)
  • Deck adhesion at 40°F (4.4°C)
  • 180 day UV resistant
  • Synthetic construction to inhibit mold growth
  • NEW! LIFETIME limited warranty
  • Meets and exceeds ASTM D1970


platinum ht-sa specification tabe

Technical Data

platinum ht-sa technical data table

Installation Instruction

Caution: Always follow Safety Instruction, Building Codes and Safe Work Practices issues by the local Govt. bodies (e.g. OSHA / WCB)

PLATINUM HT-SA must be covered by a primary roof (Asphalt & Synthetic Shingles, Metal Roofing, Tiles, Slate, and Cedar Shakes) within 180 days. For best results HT-SA should be installed on a dry deck when the air, membrane, and substrate temperature is over 40°F (4.4°C). Priming is not required for attaching to wood deck when the temperature is above 40°F. Concrete and masonry decks should be primed with a solvent or a water based primer that meets ASTM D41 for asphalt based self-adhesive membranes.

For cold weather applications below 40°F (4.4°C) a primer should be used and the laps blind nailed. Blind nail with 3/8” head roofing nails of 1” or longer in the 3” over lap area.

HT-SA is recommend for roof slope applications 2:12 and above. For steep slope applications (6:12 or greater) or when installing at temperatures greater than 100°F (38°C) it is recommended to blind nail the overlap area as instructed above for cold weather applications.

HT-SA is to be laid out horizontally (parallel) to the eave with the printed side up, using 3″ side laps and 6″ end laps.

HT-SA may also be installed vertically. For vertical installation anchor with 3/8” head roofing nails along the upper most edge 3 inches down with 6 equally spaced nails across the 36” width. Ensure roofing nails are perpendicular to the roof deck so that the head lays flat and seals well to the top surface of the HT-SA using 3″ side laps and 6″ end laps.

Always work from the low point to the high point of the roof. Apply the membrane in valleys before the membrane is applied to the eaves.

Cut HT-SA to manageable lengths and position parallel to the edge of the roof. Peel back one side of the split release sheet approximately 4 in (10 cm) then apply as positioned to the roof deck. Continue peeling back one side of the split release sheet. Press down on HT-SA with a small rubber roller to increase adhesion to the roof deck. Peel back the remaining half of the split release liner and press down on the HT-SA to adhere to the roof deck again using a small roller to improve adhesion.

For eave installation HT-SA should be applied over the metal drip edge at the eave. Do not fold HT-SA over the roof edge unless the edge is subsequently covered over by a drip edge or other flashing material. It is recommended that HT-SA extend from the eave up the roof to a point 24” inside the exterior wall. This should be above the maximum ice dam buildup line in most areas. Consult your local building code for specific requirements.

For high elevation, high wind or wind driven rain it is recommended to cover the entire roof deck with HT-SA.

Safety Notification:

FT Synthetics Products are designed with the GRIPSPOT technology for better skid protection for the roofer but product may become slippery due to high moisture, frost, rain, water, dust, debris or other conditions. Use precautions when working on the roof. Follow all local and federal safety codes when installing any roofing system including FT Synthetics products. Failure to adhere to those procedures may result in serious injury or even death.

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