Wind Damage Roof

Winds create negative and positive pressure zones that lift shingles on specific contours of the roof. There are several factors that impact wind damage to roofs: orientation of the home, style of the roof, and material used in the roofing system.

According to NOAA (National Oceanic and Atmospheric Administration), severe wind is classified as 58 mph and above. Once a windstorm reaches the severe level, it has the potential to damage roofs. Winds of 60 mph or greater begin to damage 3-tab asphalt shingles and flashing. Roofing materials like tile, slate, and cedar can generally withstand higher wind speeds than asphalt shingles but performance is highly dependent on installation techniques. For example, building code in coastal areas may require specific fasteners that can withstand hurricane winds while cities in the Midwest may not. Additionally, impacts from hail, branches and other debris during a storm can reduce the amount of wind needed to cause damage.

In non-coastal areas, most homeowners’ insurance policies cover “Wind and Hail” as single coverage category. This “Wind and Hail” coverage applies to the home, detached structures like sheds and garages as well as other belongings on the property. In areas where hurricanes are common, insurance companies may charge a separate premium for hurricane coverage that may have a different deductible structure. 

If a tree falls on your house, you should first make sure everyone is safe and immediately seek shelter. Once the storm has passed, you should contact a roofing contractor that offers emergency repairs. They can help assess the damage, structural integrity of the home and coordinate additional services that you may need (like utilities, tree removal, etc.). 

Wind damages asphalt shingles by creating a pressurized uplift that can bend, fracture, or strip off the shingles. Here’s a simple explanation of how it works: When a straight-line wind hits a home, there is an imbalance of positive and negative pressure at areas where the contour of the house changes. This creates vacuums of pressure that result in suction or uplift. This is most common at the “rakes” or edges of the roof that are hit head-on by the wind as well as the downward side of the “ridge” or peak of the roof. Roofs that have lots of hips and valleys may have several areas of the roof that are susceptible. A 3-tab asphalt roofing system is made up of sheets of overlapping material that is nailed down near the center of the sheet. The center of the sheet also has an adhesive cement glue strip that runs the length of the piece. As each new row of shingles is installed there is about 5.5 inches of “cutouts” exposed. Those cutouts align perfectly with and lay on top of the adhesive seal strip from the previously installed row of shingles.    

If you see large pieces of roofing material in your yard or notice sections of shingles that have been displaced on the roof, it is likely that your roof has been damaged by severe wind. You may also notice roof shingles flapping in the wind. In either of those scenarios, you should contact a qualified roofing contractor to perform a thorough inspection of the roof. Unless the damage is obvious (i.e. huge sections of shingles torn off) a homeowner will probably not notice wind damage to their roof. You could have lots of shingles that were bent and fractured but remain in place on the roof. When shingles bend and crease, they can also accumulate dirt and debris underneath that can cause further damage and eventually create leaks.

The best roofing systems for high winds are probably tile roofs because they can be installed to hurricane building code specifications. Slate, cedar, and asphalt architectural shingles can also be installed to withstand wind speed of 100+ mph. While there are plenty of roofing systems capable of withstanding a typical midwestern severe thunderstorm, those systems tend to be a lot more expensive than a 3-tab roof.   

No. If you have missing shingles, it is likely that your roofing system sustained damage from a severe wind event. If you are not trained to identify wind damage on a roofing system, it is best to call a professional roofing contractor to inspect the entire roof for damage. If there is other damage that goes undetected at the time of a DIY roof repair, it could cause other problems in the future and prevent you from filing an insurance claim.