Built for bigger storms: Meeting the challenge of very severe hail

By The Coffee Shops™. 

Featuring a high-performance gypsum core and coated fiberglass mat facer, USG Securock® Brand Weather Defense Roof Board helps commercial roofing systems stand up to hail, moisture, and fire risks. 

In 2018, Factory Mutual (FM) created the Very Severe Hail (VSH) designation (prior to 2018, the most stringent designation was Severe Hail). Then in 2025, FM expanded what regions fit their VSH designation. As shown in FM’s Loss Prevention Data Sheet 1-34, VSH regions now include all or parts of states across the central U.S., from Montana and Wyoming to Texas, Tennessee, Illinois, and Wisconsin. This shift was a response to increasingly extreme weather events, and the impact that it can have on roof systems and components.  

In the aftermath of this change in designation, contractors and professionals around the country were struggling to find products that could achieve such a high standard for quality, technical integrity and performance. When the team USG’s Corporate Innovation Center heard about these struggles, they dedicated themselves to developing something that would do more than protect buildings from everyday exposure.  

The result of this was the creation of their Weather Defense Roof Board. This roof board is made of a high-performance gypsum core and a coated fiberglass mat facer that allows it to deliver a “higher quality standard with more consistent results for a truly innovative, resilient solution that can stand up to puncture and impact damage for long-term protection.” In addition to its ability to meet VSH requirements, it delivers high fire, moisture, and mold resistance.  

Overall, this roof board is an ideal product to use with EPDM commercial roofing systems, as well as TPO and PVC, that need enhanced durability and protection due to environmental concerns like VSH.  

Learn more about how USG Securock® Brand Weather Defense Roof Board supports commercial roofing in demanding hail environments.