If you have noticed curled, cup-like shingles on your roof, you have a major problem. Diagnosing and fixing it is a must if you want to maintain a leak-free roof.
What Is Cupping?
Cupping is a condition that only affects asphalt shingles. It's a type of deterioration that causes the shingles to eventually deform. Cupped shingles are curled up. Curling usually starts at the corners, but it can spread to the three unsecured edges of the shingle. Eventually, the edges will be curled upward, forming a cup in the center of the shingle.
Curled, deformed shingles don't look nice, but they are more than an appearance issue. The cup in the middle catches moisture instead of allowing it to run off as it should. The curled edges also make it easier for moisture to get beneath the shingles, so leaks are more likely. Further, the deterioration of the shingles that lead to cupping also poses a problem.
Causes of Cupping
There are two root causes of cupping: manufacturing quality or age. Issues with manufacturing quality will appear within the first year or two of installation, so they are easy to pinpoint. A common quality issue is insufficient binders used in the production of the shingle. Once exposed to the elements, the binders fail and the shingle begins to deteriorate very quickly.
Age is a more common issue, which is why cupping is primarily only seen on older roofs. As the shingles reach the end of their useful life, the gravel granules that protect the service begin to wash off. Without these granules, the shingle begins to absorb moisture which leads to the curling. Poor roof ventilation that causes moisture to sit just beneath the roof surface can speed up this problem.
The good news is that if manufacturing quality is to blame, the replacement of the roof will likely be covered by either the manufacturer's or your roofer's warranty. You will need to have the cupped shingled replaced, though, as there is no effective way to fix them.
A new roof replacement is also the solution on older roofs, but your roofer will need to make sure that the cupping caused no other damages. They will check your roof decking for water damages and make repairs as needed. Your roofer will also inspect your roof vents to make sure they are adequate for the size of your roof. Only then will they replace the cupped shingles with new ones.
Contact a roofing service in your area if you notice shingle cupping issues on your roof.