Renton Roofing: Article About Asphalt Shingles Cup and Curl
One of the biggest problems with asphalt shingles is that they start to cup and curl as they age. While it's common for roofing materials to deteriorate as they age, some factors can cause shingles to become warped long before their time is due. Once curling or cupping has begun, the homeowner needs to hire a Renton roofing professional to repair or replace the roof. Only a qualified professional can tell a homeowner if a roof needs to be completely replaced, but it generally becomes cheaper for a homeowner to do so once 20 percent or more of the shingles need replacing.
While not as common in some areas of the United States, cold weather can cause asphalt shingles to age faster. This holds even more true for homeowners who regularly scrape ice and snow off their roofs. As snow and ice are scraped from the roof, some of the granule covering is scraped off as well. The granules protect the roof from the sun's harmful UV rays. Some of the granules also come off every time a person walks on the roof. As the mat base of the asphalt shingles becomes exposed to the sun, it starts to harden.
The roofers from Chase NW of Renton would be happy to answer any questions you have about commercial roofing or residential roofing.
Over time, this causes the shingles to become stiff, which starts the curling process.
Excessive heat is the main cause of cupping and curling of roofs in the United States. While heat causes asphalt shingles to age quickly, most of the damage is caused on extremely hot days when there is little wind. Once the day reaches its peak temperature in the afternoon, the surface heat of the shingles becomes so hot that it causes the shingles to bubble. Asphalt shingles need to reach temperatures of nearly 140 degrees for this to happen. While this may seem unreachable, asphalt stores heat and can be nearly 70 degrees hotter than the temperature outside. This means that damage could occur even on a day with balmy, 70 degree weather.
When the bottom row of asphalt shingles, known as the starter strip, starts to curl before the other layers, this is a sign that the roof was installed incorrectly. This commonly happens to homeowners who try to do their own roof work or hire an untrained roofer who doesn't have the proper backing. The best way to fix this is to hire a professional to correct the mistake. Depending on how far the damage has spread, the entire roof may need to be replaced. This includes the roofing deck if it has become rotted.