TL-0014 — Drying-In Roofs with TRI-FLEX® and TRI-FLEX® 15 Synthetic Underlayments Technical Letter

TRI-FLEX® and TRI-FLEX® 15 are premium water-shedding synthetic underlayments. Unlike conventional roofing felts, they do not absorb water and can be used to “dry-in” roofs for up to 6 months before the primary roof coverings are applied. However, as a water-shedding underlayment, the performance of the product relies on the ability of sloped roofs to shed water. Certain factors, such as accumulated snow, ice, wind-driven rain, debris or other causes can prevent the roof from shedding water. GCP’s synthetic underlayments are not designed to protect against standing water or water moving “upslope”, resulting from any of the above factors. In some cases, water can be forced up through the product laps or through fastener penetrations. Care should be taken during the exposure period that the product is not damaged, which can negatively affect its water-shedding ability.

For protection from standing water or water moving “upslope”, it is recommended that a GCP self-adhered underlayment be used. The maximum exposure time for GCP’s self-adhered underlayments varies by product. To extend this exposure period, TRI-FLEX® can be applied over the GCP self-adhered underlayment. Refer to Technical Letter 3 for more details on exposure limits for GCP’s self-adhered underlayments and Technical Letter 4 for slope requirements. | North America Customer Service: 1 877-4AD-MIX1 (1 877-423-6491)

We hope the information here will be helpful. It is based on data and knowledge considered to be true and accurate, and is offered for consideration, investigation and verification by the user, but we do not warrant the results to be obtained. Please read all statements, recommendations, and suggestions in conjunction with our conditions of sale, which apply to all goods supplied by us. No statement, recommendation, or suggestion is intended for any use that would infringe any patent, copyright, or other third party right.

TRI-FLEX and TRI-FLEX 15 are trademarks, which may be registered in the United States and/or other countries, of GCP Applied Technologies Inc. This trademark list has been compiled using available published information as of the publication date and may not accurately reflect current trademark ownership or status.

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GCP Applied Technologies Inc., 2325 Lakeview Parkway, Suite 450, Alpharetta, GA 30009, USA
GCP Canada, Inc., 294 Clements Road, West, Ajax, Ontario, Canada L1S 3C6
This document is only current as of the last updated date stated below and is valid only for use in the United States. It is important that you always refer to the currently available information at the URL below to provide the most current product information at the time of use. Additional literature such as Contractor Manuals, Technical Bulletins, Detail Drawings and detailing recommendations and other relevant documents are also available on Information found on other websites must not be relied upon, as they may not be up-to-date or applicable to the conditions in your location and we do not accept any responsibility for their content. If there are any conflicts or if you need more information, please contact GCP Customer Service.

Last Updated: 2022-05-06