Each year, tornadoes, hailstorms and hurricanes bring some serious damage to all types of commercial properties across North America. Severe weather has surged even earlier this summer and 2025 is shaping up to be one of the most intense years for heavy rain and high winds. It’s time to turn your attention toward your commercial roof now more than ever. From hail and tornado resistant systems to proper installation techniques and changes in insurance coverage, this year is one for the books. We’re here to help you understand your roofing risks and prepare for what the future holds.
Why 2025 is a Wake-Up Call for Roof Preparedness
Hail alone can crack, shatter or puncture membranes. Extreme hail events can even compromise your roof’s components or severely damage insulation. When it comes to tornadoes and hurricanes, high winds can peel back roof edges, rip apart flashings, damage rooftop equipment or lead to complete blow-offs. Even if the storm doesn’t come in direct contact with your building, debris carried by strong winds may make their way to your roof, causing some serious damage and expensive fixes.
This year, Factory Mutual Global (FM Global), one of the world's largest commercial and industrial property insurance and risk management companies, expanded its "Very Severe Hail Zones" (VSH). This change impacts much of the central and southern U.S., placing more properties under strict roofing standards in Louisiana, Mississippi, Tennessee, Illinois and Wisconsin. This shift means that you need to review your roof’s durability, compliance and insurance coverage. Even if you’re not insured by FM Global, many companies look to these guidelines as the industry standard.
Image Courtesy and Source: FM Global 1-28 Wind Design Data Sheet
The most significant attachment method and coverboard changes you may need to make if you’re located in the expanded VSH zones:
✔ Install a VSH-approved coverboard beneath the membrane for improved hail impact and puncture performance.
✔ Choose FM-rated assemblies that meet hail-resistant standards. These are tested for impact and durability to protect your facility.
✔ For taller buildings or those near the Gulf Coast, finding a compliant FM-approved system may require guidance or additional approvals on your customized solution.
CentiMark’s Pro Tip: Protect more than just the roof membrane. Add hail guards to rooftop HVAC units and consider impact-resistant skylights or reinforcements. Ahead of hail season, schedule a roof inspection or preventative maintenance to clear debris from drains, reinforce seams and identify any weak spots or areas of concern.
Let’s not forget about tornado-prone areas and the structural vulnerability of your facility and roof in these areas.
Image Courtesy and Source: FM Global 1-28 Wind Design Data Sheet
Here are FM Global’s recommended measures to reduce vulnerability and improve structural performance under extreme wind conditions:
✔ Consider waterproof membranes, they offer greater resistance than standard steel or gravel-ballasted options.
✔ If steel decks are used, reinforce them to handle higher wind pressures. Improve joist resistance and stability with enhanced bridging and secure chord extensions.
✔ Anchor all rooftop equipment and ensure parapet walls, coping and edge metal are secure.
CentiMark’s Pro Tip: Before storm season hits, schedule an inspection to catch red flags like lifted edges, loose flashings or unsecured mechanical units. Keep our emergency services number handy to ensure your people, property and products are protected.
At CentiMark, we provide commercial roofing solutions customized to your operations, climate risks and long-term performance goals. Whether you’ve recently been reclassified into a Very Severe Hail Zone or simply want peace of mind before the next major storm, our team is ready to help. As our Director of Technical Services and FM Global guru puts it:
“Navigating FM's assemblies while balancing their list of requirements can be quite complicated, especially with recent expansion of their Very Severe Hail Zone. CentiMark's Technical Services has the knowledge and experience to help our Sales Team provide you with a suitable FM system and walk you through FM's approval process”. - Jordan Burgunder
Need a deeper dive into FM Global roofing requirements? Our #AskCentiMark blog covers common questions, real-world examples and professional insights to help you stay compliant and storm-ready: #AskCentiMark Series: Navigating FM Global requirements for your commercial roofing needs.