While it is impossible to call any roof hurricane-proof, a properly designed metal roofing system can be capable of handling wind speeds higher than what hurricane-prone regions typically experience.
Yet, in the aftermath of a hurricane’s landfall, it is not uncommon to see photographs that show metal roofing panels wrapped around a tree or buildings missing all or parts of their metal roof.
While these images make for sensational media views, they create a skewed perception about metal roofing’s performance in high wind events.
While hurricane-proof might be a stretch, it isn’t a stretch to say that metal roofing stands up better to the wrath of mother nature than other roofing choices.
When properly engineered and installed, metal roofing continues to garner more and more attention for its outstanding performance in post-hurricane analysis.
In this article, we want to look at a few top threats to metal roofing, some key design factors, partner selection tips, insurance discounts, and after storm clean-up.
While crazy things occur when a hurricane makes landfall, the majority of roofing failures come back to one of these six issues:
Let’s examine each of these a bit further
An old adage says the best defense is a good offense. That statement certainly applies in any discussion of metal roofing and hurricane preparedness.
While local building codes typically mandate performance expectations (Miami Dade, for example), it’s always best to take things one step further and consult an engineer to discuss your project specifics and review relevant product data. It may even be prudent to request the engineer create signed project-specific calculations.
Yes, you’ll likely spend a few thousand dollars on engineering fees. Still, if it helps you better “weather the storm,” most would agree that it’s money well spent since lack of proper engineering is one of the most common reasons for metal roof failure in hurricane events.
Installation errors represent another major cause of hurricane-related metal roof failures. In some cases, the errors may be intentional and, in others, an oversight. Clip spacing is an excellent example because it directly affects panel performance for wind and uplift values.
While an engineer might properly design a standing seam system in Southern Florida with clips at 1’6” on-center, an installer might install them at 3’0” on-center.
Regardless of the reasons, placing clips too far apart, using incorrect fastener size, and placing the first fastener too far up from the eave or down from the ridge represent common problems that cause devastating roof failures, especially during hurricane events.
A metal roof system can be properly engineered and installed for high winds but fail if an underperforming door or window blows out, creating upward pressures in the home.
The New York Times highlighted a Mexico Beach, FL, house that withstood the damaging effects of Hurricane Michael in October 2018. This home suffered minimal damage while those surrounding it experienced devastation. How did this home perform so well? Engineered building components, designed to withstand hurricane-force winds, were used for the entire structure.
Properly designed and installed metal roofing often remains attached to the structure and, barring physical damage from flying debris, performs without leaks once the storm subsides.
A metal roof's overall performance depends on many variables that affect uplift pressures and wind speed.
The height of the building, shape, roof pitch, width of the building, and topography all affect the amount of force that a structure experiences during a hurricane.
Given that, it’s challenging to broadly state a specific system will perform well in all situations. That’s why we recommend working with a licensed engineer to determine the performance you can expect.
But to indicate the durability metal roofing offers, our Maxima or 238T panel systems can safely withstand wind speeds over 200 mph in many conditions.
Testing for metal roof systems ensures they remain watertight up to and including hurricane-force winds.
However, it’s extremely critical that installation details be followed to the letter to ensure resistance to wind-driven rain.
Panel damage caused by flying debris is another common culprit for hurricane-related metal roofing damage.
In many cases, metal panels experience aesthetic damage, but the roofing system remains weather tight.
The two photos below, taken after Hurricane Harvey, tell a great story.
As you can see, some of the green roof panels blew off during the storm. The blue roof panels on the roof at a nearby property remained intact; however, approximately 20% of the blue panels required replacement for cosmetic damage (shown in the second image) caused by the green roof panels when they became airborne.
While it’s unfortunate that the blue panels required any replacement, it’s important to note that since the damage was cosmetic only, the owner could complete repairs at their convenience instead of the typical post-hurricane frenzy.
Proper product selection is critical in hurricane-prone areas; however, it’s also essential to properly vet and select the right partners.
Engineers, Manufacturers, and installers all represent crucial functions in your project, and it’s vital to do your due diligence before assembling your project team.
Consult with local engineers who specialize in building and construction. Ask questions to confirm their experience with metal roofing and local building codes.
Once you’ve selected an engineer, have them design the entire roofing assembly, including the roof deck material and thickness, roof panel style and gauge, and clip/fastener spacing.
Taking this step (and the additional cost) ensures the best chance for a predictable result should a hurricane impact your building.
Work with a metal roofing manufacturer that has invested in the technology to complete in-house testing (like McElroy Metal) or uses third-party product testing to support their published load tables.
Classification and testing from agencies like UL and FM signify manufacturer commitment to engineering and safety.
If you’re trying to avoid the cost of hiring an engineer, at the very least, choose a metal roofing manufacturer with the ability to engineer their roofing systems to your local building code, which normally considers hurricane wind speeds.
Installer selection is also critical. Even the best roof will fail to perform as expected when poorly installed. The MRA (Metal Roofing Alliance) has issued a warning in the wake of the recent hurricanes, alerting consumers to the possibility of both material and installation quality concerns.
Renee Ramey, MRA Executive Director, tells consumers to “Beware of inferior material from unknown sources that some unscrupulous installers try to pass off at a discount. A good quality metal roof is made to stand the test of time and designed to offer outstanding protection.
It should have verifiable warranties, superior coatings, proper gauge and thickness for residential use, and be sourced from reputable manufacturers. Contractors also should warranty their work and be able to prove their experience and knowledge.”
In their warning to consumers, the MRA suggests some questions consumers should ask before starting a new metal roofing project that includes things like:
These questions and suggestions can help guide consumers toward reputable, safe contractors and materials. You can find the full MRA warning and guidelines here.
Some insurance providers offer discounts for homes with metal roofs for homeowners in hurricane-prone areas. While not guaranteed, the discounts offered can help reduce the cost difference between metal roofing and shingles.
For instance, State Farm® states that they offer an insurance discount for qualifying metal roofs.
When comparing different roof material types and costs, it’s important to contact your insurance provider and inquire about metal roof discounts.
After-storm repairs should be another consideration in your roofing selection. As discussed above, metal roofs represent an excellent choice in hurricane-prone areas due to their long-lasting, durable, and resistance to damage from high-speed winds.
This improved performance means there is a good chance you won’t face emergency repairs after the storm. While no roof is hurricane or windproof, selecting a metal roof means you might be able to skip the frenzy of trying to find a contractor (not to mention price gouging) in the days after the storm.
It also means there’s a good chance you’ll miss the hassle of roof leaks and insurance claims.
In closing, while no roof is genuinely hurricane-proof, metal offers distinct advantages to those in storm-prone areas.
Are you interested in learning more? Contact us to discuss the possibilities of using metal!
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