Ensuring Metal Roof Flashings Withstand High Winds

By Lauren White, RCS Reporter.

New metal flashing standard aims to improve wind resistance of metal roof systems.

Bob LeClare, the director of perimeter edge metal business for ATAS International wrote an article titled, “Against the Wind” for Professional Roofing, the magazine produced by the National Roofing Contractors Association (NRCA).  In his article, Bob enlightens readers about a new standard that was developed by the Metal Construction Association.  With hurricane season approaching, this article is worth the read!

After high wind events, such as Hurricanes Charley, Ivan, Katrina, Ike and Irma, the Roofing Industry Committee on Weather Issues Inc. (RICOWI) investigated metal panel roof system failures.  Over the years, they have inspected hundreds of roof systems and in every report they  identify metal flashing failures as a reason that metal panel roof systems fail.  

The Metal Construction Association developed a new standard, ANSI/MCA FTS-1-2019, “Test Method for Wind Load Resistance of Flashings Used with Metal Roof Systems,” with the intent of improving metal roof systems’ wind resistance.  This standard supplies a methodology for testing metal roof flashings.  “When flashings fail, metal roof panels are exposed at the edges and ridges, and the roof system can peel.  When a flashing system has been tested to resist design wind loads, it is less likely to fail, and the roof panels are more likely to stay secure,” Bob explains

“MCA recognizes a key to improving metal roof system performance is to improve the wind resistance of flashings used with these systems,” Bob shares.  “In 2015, MCA formed a steering committee to develop a standard that would prescribe methodology for testing metal roof flashings.”  In 2016, after the initial draft was completed, three independent test labs were contracted by the committee to test five different metal roof flashing systems.  By June 25, 2017, the American National Standards Institute (ANSI) approved the final draft, ANSI/MCA FTS-1-2019. 

There are four sections included in the standard: test apparatus, test specimen, loading procedure and test report, and a commentary section.  The Metal Construction Association, “plans to propose testing metal roof flashings, per the new standard, to be included in the next International Building Code® edition scheduled for 2024,” Bob shares.  The standard is currently available for manufacturers and specifiers to use.  

Read the article to learn more about the new standard from Bob LeClare at ATAS.

Learn more about ATAS in their RCS directory.