It’s prime time for thunder, lightning and hailstorms. In fact, two-thirds of lightning-related fires occur between June and August. With that in mind, how do you separate fact from fiction when it comes to protecting a home from one of Mother Nature’s most powerful forces? Take this pop quiz:
Fact or Fiction: The type of roof on a home makes a difference on whether it might be struck by lightning.
Answer: Fiction. Lightning typically strikes the highest object, regardless of what material it is. According to the National Weather Service, height, pointy shapes and isolation are the dominant factors for where a lightning bolt will strike. The presence of metal makes no difference. That’s why natural objects like trees and mountains (that are obviously not made of metal) frequently get struck.
The bottom line: Metal roofs are no more likely to draw or attract lightning than any other type of roof. In fact, metal is used frequently in the most lightning-prone areas because it performs exceptionally well in severe winds, hail and rain that are often experienced along with lightning storms.
Fact or Fiction: It’s rare that a home will get struck by lightning and if it does, the biggest danger is it catches on fire.
Answer: Fiction. The National Lightning Safety Institute estimates 1 out of every 200 homes will be struck by lightning per year. According to the CDC, a house is a safe place to be as long as you avoid water, electronic equipment (including corded phones), TV cables, concrete, doors and windows.
Most commonly, lightning causes a power surge that damages electrical systems and appliances. That said, fire is a definite potential. Each year, the U.S. Fire Administration estimates 17,400 fires are attributed to lightning. A properly grounded metal roof may work to help conduct energy from a lightning strike over a broader area of the roof, reducing the amount of heat transferred to the building and reducing the potential damage due to fire. However, most fires are caused by lightning strikes outside the home when nearby trees, brush or other organic material ignite. Quality metal roofs also work to protect against wayward sparks and carry Class 4 ignition protection—the highest level of protection available against wildfires.
Fact or Fiction: Roof damage from large hailstones is always visible, making it easy to spot needed repairs.
Answer: Fiction. On typical asphalt roofs, hail can cause hairline cracks and displace shingles; damage that can be hard to detect. A homeowner may not realize their roof has been compromised until it’s too late and a leak is found, potentially resulting in costly damage to a home’s interior, as well.
Fact or Fiction: The underlayment selected is just as important as the roofing material when it comes to performance.
Answer: Fact. No matter what the roof type, quality underlayment is essential. Underlayment helps ensure a roof is watertight and protects against ignition in wildfire-prone areas. Also important is a quality roof installation that ensures the roofing system is resistant to damage caused by severe storms, hail, and, in the case of fire, burning embers.
Fact or Fiction: A roof with a Class 4 hail impact rating is the best a homeowner can get.
Answer: Fact. Class 4 hail refers to a roof material test that measures a roofing product’s ability to withstand damage from hail impact. Specifically, this is the UL2218 Impact Rating test conducted by Underwriters Laboratories (UL), a not-for-profit organization that independently tests and certifies roofing products.
The UL2218 Impact Rating test is considered the national standard for measuring a roof’s ability to withstand hail damage. During the test, steel balls of various sizes are dropped on the roofing product from varying heights. Based on the results, roofing products are certified as Class 1, Class 2, Class 3 or Class 4.
A Class 4 rating is the highest possible rating and indicates that the roof can withstand hail impact. Many quality metal roof systems achieve Class 4 hail ratings, making them a suitable choice for regions that experience frequent lightning, hail and high winds.
For more information about top-performing roofs that can add long-lasting resiliency and help protect a home in extreme weather, get a free copy of MRA’s Metal Roofing Buyer’s Guide.