Why Asphalt Shingles Fail Prematurely
East Bay Roofing Company Shares Factors to Consider
Asphalt shingles, the most popular residential roofing material across the country, have the undisputed advantage of low initial cost. Whether they remain a bargain in the long term depends on how long they last. And how long they last varies tremendously. You may know someone whose asphalt-shingled roof has held up for thirty years or more. That homeowner might swear by asphalt shingles, and with good reason. However, another homeowner may have a horror story about having to replace asphalt shingles only two years after installation! This difference in longevity is due to several factors that are essential to understand when roofing with asphalt shingles.
The first factor in asphalt shingle life is the quality of the shingles themselves. Whether the base is felt or fiberglass, asphalt shingles rely on asphalt for waterproofing. In addition, they rely on the top layer of ceramic granules to protect the asphalt layer from the degrading effect of UV radiation. The asphalt has two jobs: to keep water out and to hold the ceramic granules in place. If the asphalt is of low grade or if the manufacturing process does not ensure proper adhesion of the ceramic granules, the shingles will deteriorate quickly. Bad shingles may also split in random places.
Installation, including taking care of what is under the shingles, is as important as shingle quality. The decking, sheathing, and attic have to do their part to keep the shingles in good shape. Roofing paper must be installed under the shingles; whether you do the job yourself or hire a roofing contractor, make sure this step is not skipped. Situations that allow heat to build under the shingles cause the adhesive to fail and/or the shingles to deform (“cupping”). If you have one layer of shingles and are considering whether to have a second layer applied over it, keep in mind that stripping off the first layer does allow access to the sheathing to make repairs there.
Weather contributes to aging of asphalt shingles. Freezing temperatures allow ice to form in the smallest cracks, expanding the shingles. Here in the Bay Area, summertime can also be hard on asphalt roofs when roasting days alternate with cool nights. The result is thermal shock to roof shingles: rapid expansion and contraction stresses shingle materials to the point where fissures develop. Fissures provide moist habitat for algae and moss that can damage the shingle, particularly during damp weather, in shade, and when debris has been allowed to accumulate on the roof. Steep roofs are much better at shedding moisture and debris than low-slope ones. For this reason, shingles on high-slope roofs tend to last longer.
To avoid thermal shock, roofs need to be kept from overheating in summer. One option that helps is light-colored shingles. White shingles, in fact, may come with an “energy star” rating that allows part of the installation cost to be written off at tax time. No matter what color shingles you have, ventilation beneath the roof is key to minimizing shingle damage from heat and from thermal shock. You don’t have to wait until you need roofing repair done to take a look in your attic and see how well ventilated it is. Improvements here can save years on the life of your asphalt-shingle roof.
Contact Your Bay Area Roofing Contractors Today!
Century Roof and Solar uses only quality roof and gutter products from manufactures with the highest of standards, and quality control. Call us today at (888) 233-7548 to learn why we are the Bay Area’s premier roofing company.