Many different factors go into determining which type of shingles is the best option for a home’s roof. One factor that always makes a big difference is where you live since the local climate can play a major role in how long a roof may last and which type of shingles will work best.
An Overview of Impact-Resistance Ratings
Most asphalt shingles have a rating that expresses how resistant they are to impact. The rating scale starts at Class 1 and goes up to Class 4, the highest rating. To qualify for an impact-resistance rating, the shingles must meet the UL (Underwriters Laboratory) 2218 standard requirements. That means they must be lab tested by repeatedly dropping various sizes of steel balls onto the shingles from different heights. This test aims to simulate the impact of hailstones and flying debris to see how much force the shingles can withstand without cracking or breaking. The final rating is then based on the size of the steel ball the shingles can withstand before getting damaged.
To achieve a Class 4 impact-resistance rating, the shingles must withstand being hit multiple times by a 2-inch steel ball dropped onto them from a height of 20 feet. Class 3 shingles must withstand the impact of a 1.75-inch steel ball. Class 1 and 2 shingles can only withstand the impact of 1.25-inch and 1.5-inch steel balls respectively.
What Makes Class 4 Shingles More Impact Resistant?
Class 4 shingles can withstand larger impacts without being damaged due to how they’re constructed. Shingles with lower impact-resistance ratings typically consist of a fiberglass (or sometimes cellulose) base coated with a mixture of asphalt and tar. Class 4 shingles instead have a polymer-based mesh base that makes them much more flexible. Polymers are added to the asphalt coating to strengthen and bind everything together.
Pros and Cons of Choosing Class 4 Shingles for Your Roof
The first thing to note about Class 4 shingles is that their increased strength comes at a premium. That means the cost of installing the new roof will be quite a bit higher than it would be if you opted for one of the lower classes. Nonetheless, the extra cost can be well worth it, especially if you live in an area prone to major hail storms or hurricanes because there’s less chance of your roof getting damaged by a storm. That means a roof with Class 4 shingles will typically last longer than a roof with other types of shingles.
Another reason it can be worth paying the higher price for Class 4 shingles is that they will often help you save money on your homeowners insurance premiums. Most insurance companies provide discounted premiums for houses with Class 4 shingles because the shingles lessen the chances of the company having to pay out on a claim to repair or replace the house’s roof. Some insurance companies will only reduce your premiums by around 10% if you have a Class 4 roof. However, many companies will give you anywhere from 25% to 35% when you replace your old roof with Class 4 shingles. You can also often get at least a small discount if you opt for Class 3 shingles instead. Depending on how much of a discount your insurance provider offers, the amount you save on your premiums over the life of your new roof could more than offset the higher initial cost of the Class 3 or 4 shingles. The insurance savings combined with the longer lifespan of a Class 4 roof mean that it’s often the most cost-effective option in the long term.
Understanding Wind-Resistance Ratings
Most asphalt shingles also have a separate rating that expresses the maximum wind speeds they should be able to handle without breaking or getting torn off the roof. This rating scale starts at Class A and goes up to Class H. Class A shingles can only withstand maximum wind speeds of up to 60 miles per hour. While this may be sufficient in some parts of the country, Class A shingles aren’t recommended for anywhere that experiences major thunderstorms or hurricanes. Class H shingles should be able to withstand wind speeds of up to 150 mph, which should ensure the roof doesn’t get damaged by anything other than an extremely powerful storm.
The best way to determine how wind-resistant your shingles should be is to look at FEMA’s U.S. wind zone map. This map splits the country into four zones based on the maximum wind speeds an area is likely to experience. Almost all of Georgia and South Carolina are in Zone 3. This is the second-highest zone with potential winds up to 200 mph. That means you generally want to go with the highest wind-resistance rating available since it will lessen the chances of damage and potentially increase the lifespan of your roof. While you will have to pay more for shingles with a higher rating, you may get a further discount on your homeowners insurance if your shingles have both a high impact-resistance and wind-resistance rating.
Other Factors to Consider When Choosing Shingles
In addition to wind- and impact-resistance ratings, a few other factors can impact how long a shingle roof potentially lasts. One factor that can make a much bigger difference in the lifespan of a roof than many people realize is the color of the shingles. Heat and weathering from sun exposure contribute to shingles deteriorating and becoming more susceptible to damage. In warmer Southern climates, a roof with darker shingles typically won’t last as long as a roof with lighter-colored shingles. That’s because darker colors absorb much more heat from the sun, resulting in them deteriorating faster. Lighter colors reflect much more sunlight and don’t get nearly as hot. That also means a lighter-colored roof can help keep your air conditioning costs lower since it results in your home not heating up as much or as quickly as a darker-colored roof.
One other thing you may want to consider in a hotter, more humid climate is choosing algae-resistant shingles. Algae growth is a common issue in humid climates and can also contribute to a shingle roof not lasting as long. The reason is that the type of algae that grows on asphalt shingles feeds on the limestone they contain, which weakens the shingles and causes them to deteriorate faster. Algae-resistant shingles contain copper granules that deter algae growth and help protect the roof. Instead of paying extra for algae-resistant shingles, the other option is to have your roof cleaned and treated regularly to eliminate algae.
Since 2009, Fraser Roofing, LLC has been helping homeowners throughout much of Georgia and South Carolina with all of their roofing needs. We offer a wide selection of shingles and can advise you on which options best suit your home’s roof. You can also turn to us whenever you need a roof inspection or any roof repairs or gutter services. If you need to replace your roof, contact us today to learn more about your options.
