TL-0016 — Exposure Guidelines TRI-FLEX® and TRI-FLEX® 15 Technical Letter

TRI-FLEX® and TRI-FLEX® 15 synthetic roofing underlayments are not meant to be left permanently exposed to the sun. In general, the membrane should be covered with the final roof covering as soon as possible. When installed with roofing nails or staples both having a 1” minimum diameter plastic/metal cap, TRI-FLEX® underlayment may be left exposed up to 180 days and TRI-FLEX® 15 underlayment may be left exposed for up to 30 days. Please see the product data sheets for further information on installation procedures.

Alternate fasteners are approved for both TRI-FLEX® and TRI-FLEX® 15 underlayments for short term exposure of up to 3-days, provided the guidelines below are followed.

Hand driven roofing nails:

If the final roof covering is to be put in place within 3-days after membrane installation, hand driven roofing nails are acceptable for use, provided the roofing nails are installed 90° to the substrate without being overdriven. The nail head should be tight against the underlayment and the substrate. This modified installation and exposure guideline is not recommended if high wind is expected during the 3-day exposure period. The standard fastening method of cap nails/staples should be followed if high winds are expected regardless of the exposure period prior to installing the final roof covering.

Pneumatically driven coil nails:

Pneumatically driven coil nails are also acceptable for use if the final roof covering is to be put in place within 3-days after membrane installation, provided the pneumatically driven coil nails are installed 90° to the substrate without being overdriven. The nail head should be tight against the underlayment and the substrate. This modified installation and exposure guideline is not recommended if heavy rain or high wind was expected during the 3-day exposure period. The standard fastening method of cap nails/staples should be followed if high winds are expected regardless of the exposure period prior to installing the final roof covering.

If exposure longer than the recommended limits are anticipated, please contact your local GCP technical sales representative

gcpat.com | North America Customer Service: 1 877-4AD-MIX1 (1 877-423-6491)

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 www.gcpat.com. 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: 2018-12-28

https://gcpat.com/en/solutions/products/tri-flex-synthetic-underlayment/tl-0016-exposure-guidelines-tri-flex-and-tri