Hurricanes

How Hurricanes Damage Roofs

If you live in a region that can be affected by hurricanes, like the Gulf of Mexico or the Atlantic coast, making sure your roof can withstand extreme storms is vitally important. Not only can the extreme winds generated by a hurricane tear or blow off shingles, but gutters, satellite dishes, roof vents, and other objects attached to your roof can be torn away become airborne hazards. Objects attached to your roof should be inspected and firmly secured (or taken down, if possible) prior to a high-wind event. Water damage is also a major concern with hurricanes, as wind damage to roofing components can provide rain with easy access to the inside of a home. This is why modern roof systems include roofing underlayments—weatherproofing membranes installed on the roof deck before the shingles are attached—as a vital secondary barrier against leaks.

How to Prepare and Recover From a Hurricane 

There’s no such thing as a hurricane-proof home, so it’s important to fortify your roof in advance of an approaching storm. Look for any areas where your roof may be weak or damaged and, if possible, have a professional make repairs. Trimming overhanging trees near your home is also important. With 100+ mph winds, even healthy trees are at risk of storm damage, so check in the early spring before hurricane season starts. In general, tree branches should not be within six feet of your home.

Hurricane Wind Scale

In addition to your roof, there are important steps you can take to protect your family and the rest of your property. Park your car in a covered area and stay in a safe area of your home—away from windows—until the storm passes. Also, be prepared for storm surges: rapid sea level rise can accompany hurricanes that hit areas close to coastlines and rivers. Just six inches of storm surge can be difficult to stand in, and one foot of storm is enough to move a car, so don’t take any unnecessary risks¹. Prior to any major hurricane, give serious consideration to purchasing adequate flood insurance based on the location of your property.

Don’t forget emergency essentials such as a weather radio, flashlight with batteries, copies of important documents, medicine, a first-aid kit, and plenty of food and water. Also, stayed tuned for weather updates and evacuation orders. If an evacuation order is issued, getting out of the area should be your top priority.

Hurricane Facts 

Most declared disasters occur due to tropical storms and hurricanes. Eight of the ten costliest disasters in America’s history have been the result of hurricanes occurring since 1990. The flooding caused by hurricanes accounts for hundreds of millions of dollars of property damage every year.

Research from the National Climate Assessment (NCA) shows the number and severity of storms increasing every year. Since the 1980s, the number of Category 4 and 5 hurricanes has risen by 80 percent because of higher sea temperatures in the Atlantic region. NCA models also predict wetter hurricanes in the future, with greater rainfall rates for hurricanes in warmer climates and increased rainfall near the center of hurricanes.

When Hurricane Dorian—one of the two largest hurricanes ever to make landfall in recorded history—hit the Bahamas in 2019, it was a Category 5 hurricane with wind speeds of 185 mph and 25-foot storm surges. The storm caused $3.4 billion in damages in the Bahamas² and left 29,500 people with damage to homes and assets.

While hurricane winds are dangerous, the rain and flooding they often produce can be just as perilous. Most of the damage caused by Hurricane Harvey in 2017 wasn’t produced by winds, but by extreme flooding after it stalled over Texas, engulfing the area in an estimated 33 trillion gallons of flood water³.

How Hurricanes Form

Hurricanes, or tropical cyclones, start out as streams of low-pressure air that move through the moisture-rich tropics before emerging as fierce storms that bring massive rainfall and high-speed winds that leave flooding storm surges in their wake. The category of a hurricane (on a 1-5 scale) is determined by its sustained wind speeds, with Category 4 and 5 storms capable of catastrophic damage. A Category 1 hurricane starts at 74 mph, while a Category 5 hurricane has wind speeds greater than 157 mph. While Category 1 and 2 storms are weaker, they present the threat of stalling over a populated area, dumping excessive amounts rain, and causing rivers and low-lying areas to flood. Hurricanes occur most often from June to November, threatening the Caribbean, the Gulf of Mexico, and the eastern seaboard of the United States.

Sources

1. https://www.wunderground.com/prepare/storm-surge

2. http://idbdocs.iadb.org/wsdocs/getdocument.aspx?docnum=EZSHARE-1256154360-486

3. https://www.washingtonpost.com/news/capital-weather-gang/wp/2017/08/30/h...