Understanding Roofing Shingle Granules
by William Gerard
One of the more important aspects of your roofing is the coating of small rocks on the surface of your shingles. Learn more about these shingle granules so you can better monitor the condition of your roof.
What Are Granules?
The granules attached to the exterior surface of asphalt shingles are made from aggregate, which is crushed stone and gravel. The primary reason for adding the granules to the shingles is to increase the water-shedding ability of your roof. The granules also increase fire resistance, which makes your roof safer. Further, the protective coating of granules helps protect the shingles from the damaging rays of the sun.
Granules also serve other purposes. Uncoated asphalt shingles, for example, would stick together. This sticking would make installation much more complicated. Further, granules are one of the methods used to add color to shingles. Instead of a flat color, the type of stone used to form the granules can add multiple dimensions of color, as well as increase reflected light so the roof is much more attractive.
Common Damages
Weathering causes most premature granule damage. Impacts from falling tree branches or hailstones, for example, knock the granules off. Repeated exposure to heavy rain and sheet flow on the roof can also dislodge granules. This problem becomes worse as the shingles age and near the end of their useful life. Moss growth on the roof as well as clogged gutters can increase the water load on the shingles, thus increasing the rate of granule loss.
Traffic patterns on the roof are another common cause of lost granules. Each time someone walks on the roof, they are compressing the shingles and knocking loose granules. For this reason, it is best to stay off the roof unless absolutely necessary. Squirrels, birds, and other animals can also cause some granule loss by walking on the roof, but not nearly at the rate of when heavier humans are up there.
What to Watch For
You can monitor for granule loss without ever leaving the ground. If your shingles lose a large amount of granules, they will develop smooth spots that look shiny from the ground. You may also notice an increase in the amount of gravel in your gutters, at the base of downspouts, or along the ground beneath the drip line of the roof.
Shingles that have suffered major granule loss will often begin to curl upward at their edges. This is because the bare shingle material is much more absorbent, so moisture causes the shingles to curl.
Contact a roofing service if you notice signs that your shingles may be deteriorating.
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About Me
Do you know how to tell if you have problems with your flashing, loose shingles, or damaged tar pitch? Well, I didn't either until I experienced some of those issues on my own. One day, I realized that my roof was leaking and that I needed to find a solution fast. After contacting a professional roofing company, they were able to solve my troubles and teach me the signs of trouble. I want you to avoid the same types of hassles, which is why my blog is filled to the brim with information about roofing and home ownership. You never know, these tips could really come in handy!