Don't Be Blown Away
Understanding Your Shingles' Wind RatingMichael Lawson, Writer
Homeowners planning to re-roof their homes or select a roof for a new house usually base their decision on color, style and price. Modern asphalt roof shingles are available in a wide array of colors, shapes and textures. However, in addition to concerns about impact resistance, algae resistance and color, homeowners should also consider a shingle’s wind resistance ability when talking with their roofing contractor.
Extreme weather, such as tornadoes, hurricanes and good ol’ Nor’easters, makes the news several times a year. News reports of storm aftermath usually include images of damaged houses, many of which are missing roof shingles. The shingles installed on a roof should be strong enough to withstand high-force winds.
One helpful and informative resource is the New Wind Standards for Asphalt Shingles. It details the wind-resistance classification system developed by ARMA, the Asphalt Roofing Manufacturers Association, and describes in clear and understandable terms what homeowners should know to get the best wind-resistant shingles for their homes.
ARMA conducted more than 14 years of research and wind-tunnel testing to prepare the report. This new classification system has now been added to the International Building Code, which is used by most builders and municipal inspectors.
According to ARMA, homeowners need to consider two factors before buying any brand of asphalt shingles: the wind zone location of the house and the wind classification of the shingle.
Location And Classification
The wind zone location can be obtained from the local building code enforcement office. Based on the maximum average wind speeds, the wind zone classification in most of the continental United States is 90 mph. However, the Eastern coastal region of the U.S. has wind zone designations of up to 110 mph.
A shingle’s classification is denoted by a letter corresponding to its wind zone rating.
The classifications are:
- Up to and including 90 mph – Class D
- Up to and including 120 mph – Class G
- Up to and including 150 mph – Class H
Wind standards are important not only for protecting against hurricanes or tornadoes but also from more common high-wind situations such as severe thunderstorms and frigid winter weather. When properly installed by a qualified and experienced roofing contractor, asphalt shingles offer proven performance in resisting high winds.
Many lines of Atlas asphalt shingles have Class H wind resistance ratings: StormMaster® Shake, StormMaster Slate, Pinnacle® Pristine, Briarwood Pro™ and ProLam™. Available in a variety of styles and with a number of desired performance features, they also are priced to match virtually any homeowner’s budget.