Asphalt shingles were first introduced to American homes in 1901, and they slowly found their way onto more and more homes as the years passed. They became so popular that by the year 1939, 11 million squares were being produced every year. No matter where you look today, asphalt shingles can be seen installed on homes and businesses throughout the US.
Although asphalt shingles are an affordable and superior roofing product that has a service life between 20 to 30 years, there’s also a chance that over time, some individual shingles will start to curve, cup, or curl. It may take several years before you notice any damage. When you do notice these types of shingle deformities, a new roof is most likely in your near future. However, it’s also important to understand what may have caused the cupping and curling before you make your next investment.
Below are five common causes of cupping and curling in asphalt shingles
Insufficient Binder Coatings
If cupping or curling occurs within months after installation, there’s a good chance of a manufacturing defect in the product itself and not your home. When asphalt shingles cup or curl this early, it’s generally due to an insufficient amount of binder coating on the backing of the shingles.
Asphalt shingles are manufactured with fiberglass or organic matting on the backing. A coat of asphalt is applied to both materials, which ensures a better bond to which the granules can adhere. When manufactured with insufficient binder coatings, the granules on asphalt shingles can easily wash off. This is what causes the back of the shingles to curl or form a cup-like shape.
If you suspect that insufficient binder coatings are the reason for the cupping? You should immediately contact the manufacturer and start the warranty claims process.
Asphalt shingles are attached to the plywood with a layer of water protection material (tar paper/ice&water shield) in between the two. If a roof has inadequate venting, this can trap moisture and heat in between the layers, which causes cupping and curling of the shingles. One of the best ways to solve this problem is to make sure both gable ends have a vent. You can also install perforated soffits under your eves and look into installing a ventilated ridge cap if your home doesn’t already have one.
It’s essential for your attic to have adequate ventilation. This is not only to stop asphalt shingles from cupping and curling, but also to prevent mold and mildew from forming and entering the home’s atmosphere. Attic insulation is designed for either hot or cold air to flow over the top and escape via ventilation components. It also blocks hot or cold air from escaping through the ceiling from inside the house, keeping your home comfortable.
If bundles of shingles that are waiting to be installed on a home are subject to poor storage, this can cause cupping and curling shortly after installation. If the retailer stores bundles of shingles without cover, shingles that are still trapped in the plastic packaging can get saturated with rain and exposed to extreme weather conditions. This can make new shingles weak before installation, and they generally fail within ten years or less.
The best solution for this issue is to purchase your shingles from home improvement stores or lumber yards that store their shingles inside. You should also make a note on where your contractor may have purchased them, in case you take that route. Getting a warranty claim from a manufacturer is a lot easier said than done. You should keep all receipts and records if you think poor storage played a role in your defective shingles.
Installing the Wrong Asphalt Shingle
Most standard 3-tab and architectural shingles will perform well in cold and hot weather climates. Although depending on where you live, you may need to consider an asphalt shingle designed specifically for extreme cold or hot weather conditions. Installing the wrong asphalt single in either situation can cause shingles to cup and curl.
If you’re unsure about the correct shingle application for your location, check with your roofing contractor or call your local home improvement center for recommendations.
Ice Build Up and Improper Snow Removal
Ice dams can create a big problem for many homes. Not only do they cause shingles to curl and cup, but they also create nightmares with interior ceiling leaks and mold. Ice dams form by the heat that escapes from poorly insulated walls and ceilings or water that slowly drips and freezes off the roof.
Another culprit is improper snow removal. Shovels and rakes should be used downward and not used in an upward motion to remove ice and snow. This can cause significant damage to the edges of the shingles and remove the granules, which will cause the shingles to curl and cup.
What’s the Best Method to Stop Cupping and Curling?
You shouldn’t install asphalt shingles on top of an existing layer of shingles. This can create gaps and improper adhesion of the backing materials. It’s always better to strip the old shingles off and start new for the best results and longest service life.
Another easy task to stop cupping and curling is installing at least three feet of ice and water shield along the bottom edges and in the valleys before you install the shingles. Then you can tar paper the rest or simply cover the entire roof with ice and water shield for the best results.
Additionally, you should utilize the tips provided above to make sure your roof can breathe and hire a professional roofing contractor to install your asphalt shingles. A well-designed ventilation system coupled with expert installation is the best method to stop asphalt shingles from cupping and curling. For more information about asphalt shingle removal and installations services, please fill out the contact form below.