Asphalt shingles look great, are very durable, and come in a variety of colors. They are excellent on sloped roofs, which is why they are by far the most popular residential roof system.
However, UV light has a harsh effect on asphalt roofs. That is why almost all shingle roof systems are installed with granules, which is what gives shingles their color. Most flat modified bitumen roof systems are installed with granules as well.
At Chaffee Roofing, we get a lot of clients looking for solutions to UV light damage, particularly on older asphalt roofs where the granules are either missing or were not part of the original roof system.
What exactly are the harsh effects of UV light on asphalt roofs? To help our clients understand and care for an asphalt roof, we put this post together.
Here comes the science bit
UV radiation comes from exposure to the sun. At least part of your roof, if not all, will feel the effects of sunlight during the day. The longer the day and warmer the climate, the more time the UV light will have to do its work.
UV light will change the chemical makeup of the compounds in the asphalt shingle. This happens deep in the shingle. The protective coating on the shingle will deteriorate when the hydrocarbons come into contact with the oxygen in the air.
Heat, cold, rainwater, and wind will accelerate the process, leading to cracking and peeling overtime.
Long term effect of the damage
The UV light will be working on your asphalt roof from day one. The long-term damage may not be immediately visible, but it will be there.
The cracks will widen. Water will seep into the structure of the building below. In cold weather the freezing moisture will expand, making the situation worse. The expansion caused by the heat of the summer sun followed by contraction during the cooler night, also known as thermal shock, will do further damage.
The harsh effects of UV light on asphalt roofs are scary, but you can take preventative measures.
Preventing damage to asphalt roofs
Inspection is the key to preventing damage to your asphalt shingles.
Get an expert up on the roof at least once a year. Wind, snow, and rain will loosen and wash away the tiny pebbles that reflect the sun’s rays. Replace any shingles suffering UV damage.
Other asphalt roofs may have a protective film on the shingles.
Coating the shingles with an appropriate product will improve the look of the roof and will increase protection against UV rays. This may be a good solution if your U/V protection is gone, but the shingles themselves are still in good to decent shape.
At Chaffee Roofing we know about asphalt roofs.
We can help you with any problems.
Our experts will guide you through installation and annual maintenance.
Call us today with all of your roofing questions.