The answer to whether or not metal roofs are wind resistant is like one of those age-old logic problems involving If/Then statements because, while not all metal roofs are wind resistant, the most wind-resistant roofs are made out of metal. In other words, if you design your roof to withstand the wind forces, aka wind uplift ratings, predicted in your geographic location, odds are you'll enjoy a relatively maintenance-free roof for decades to come.
Metal Roofs: Explore a Highly Wind Resistant Roofing Material
Typically, metal roofs are made from continuous sheets of metal that run the entire span of a roof, from the eave to the ridgeline. Unlike more traditional shingle or tile roofs, which consist of a plethora of seams where wind can penetrate the roofing material causing damage, metal roofs have fewer exposed edges. We should note that metal roof systems could also be designed to mimic stone or shingle products. However, in areas where tornado and hurricane-force winds are a possibility, it's better to use a metal panel system.
Several factors determine how well your metal roof holds up under continuous and/or storm wind scenarios.
Was the building engineered specifically for your geographic location? Metal buildings are not one-size-fits-all entities. A building constructed in California must be built to meet more rigid seismic codes while a building in Oklahoma or Kentucky should be designed to outlast tornadoes. Make sure that your metal building plans are engineered to withstand both typical and extreme weather patterns in your area. We recommend meeting with your local building department to become familiar with the building codes in your area. Metal building manufacturers will also work with you to ensure your metal roofing products are wind resistant.
Is the roof installed via the manufacturer's recommendations? Metal roofs have the highest strength to weight ratio of any roofing material available. However, that ratio is entirely dependent on the quality of their installation. In a FEMA publication touting the advantages of metal roof systems in high-wind areas, several examples of failed metal roofs are shown. In every case, it was the installation methods - not the materials or the design - that were the problem. If your roofing contractor is not familiar with metal roof systems or the wrong materials are used, your metal roof will not perform as it was designed. Thus, you should be careful to:
- Work with licensed and experienced contractors. While installing a metal roof can be DIY job, we don't recommend that route if you live in an area with more extreme weather conditions. To ensure your building is stable and your roofing system is installed correctly, you are best off working with a licensed contractor who is familiar with metal building and roof construction.
- Use the correct materials. If you live in an area where rainfall and snow are just as likely as high winds, you'll want to use a standing seam hydrostatic system that is designed to resist water infiltration under hydrostatic pressure. If water isn't as much of a concern, a water-shedding roof system will probably suffice. Using a water-shedding system when a more durable option is recommended will lead to water damage. This undermines the roofing materials, which will then compromise their performance in high-wind conditions. Or, if you live near the coast, you need to select roofing materials, clips and fasteners that are resistant to salt water. Not selecting the correct materials will lead to material failure when it matters most.
- Match your materials to the underlayment. The underlayment is an added means of moisture control. However, if roofing materials aren't matched to the underlayment, you'll wind up with metal roofing panels that shear right off the building - causing a significant safety issue - while the secured underlayment remains in place. Selecting the right fasteners for the underlayment will increase the roof's wind-resistance.
Has the metal roof been properly maintained? While metal roofs are low maintenance, they still do require maintenance. Debris should be removed from the roof and gutters at monthly or seasonal intervals, depending on the need. Flaking or eroding protective coatings should be repaired or replaced as needed. Broken or dysfunctional gutters and downspouts should be repaired or replaced. By keeping your metal roof in good shape, you'll prevent the corrosion, which eventually compromises the structural integrity of both the roofing system and the building itself.
If you live in an area that experiences intense heat, you may also want to consider reflective metal roof products that protect the roof from the sun's rays, which are one of the most destructive elements of all over the long-term. In addition to a sturdier roof, you'll also benefit from energy savings.
Please contact the representatives at Whirlwind to discuss the design of a wind-proof metal roof for your next construction project.