20 May Wind Resistance and Metal Roofing
Here in North Carolina, wind resistance is important for your roof. Your roof provides ultimate protection for your home and your belongings. If anything jeopardizes the protection given by your home’s roof, the protection of everything in your home is jeopardized.
Most roofing materials depend on gravity and their own weight for wind resistance, or at best, upon failure-prone sealants. Gravity can be overcome if the force is great enough and sealants are uncertain at best and eventually will fail. Every single shingle tab of a traditional roof is prone to uplift as nothing mechanical holds the shingles in place.
McCarthy Metal Roofing provides interlocking metal roofing panels from Classic Metal Roofing Systems. A mechanical lock between the panels holds them in place, rather than just gravity or some sort of glue.
The Impact of the Wind on a Roof
Contrary to what you may think, the greatest chance of wind damage on a roof is not on the side the wind is hitting. Instead, the greatest pressures are actually the uplift pressures on the back side of roof created by the wind hitting the roof, being directed up over the home, and creating a whirling vacuum effect on the other side.
How Our Metal Roofs Are Tested
The wind tests performed on metal roofs consist not of some giant fan and a wind tunnel but of an uplift pressure test. The product being tested is installed on top of plastic bagging which is then filled with air. The resulting pressure is trying to push the metal panels off of the roof deck. This is similar to the vacuum pressures created on the back side of the roof during a windstorm. This is how the most strict wind tests are performed on metal roofs.
Roof Age and Wind Resistance
Because other products depend upon gravity or glues for wind resistance, those products lose wind resistance as they age. However, because our premium protection metal roofs feature interlocking panels, they do not lose wind resistance with age and will perform the same in 30 or 40 years as they do when they are new.