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Whether you’re doing a roof repair, a first installation or a full replacement, you will probably notice little bits of rock falling off the shingles and scattering around the worksite. Good contractors typically sweep the area for any debris when work is done for the day, but have you ever asked what those granules are?

Understanding Asphalt Shingle Granules

This short discussion on asphalt shingle granules will give you a better understanding of what the granules are and why they are important in shingle manufacturing and performance.

Of What Are the Granules Made?

Asphalt shingle granules are little bits of stone. They are crushed and screened bits of hard rock. Roof granules follow exact size specifications before they are applied to the shingles. Most of the color you see on your choice of asphalt shingles is the color of the granules.

Why Do They Fall Off During Installation?

Many granules fall off new shingles as the shingles are being installed. Some granules end up in the rain gutters and others fall on the ground. You don’t have to worry about them as they are simply excess granules.

Are They Important?

Very much so. The granules provide your roofing system its long-lasting color, but their role goes well beyond aesthetics.

Granules also give your roof plenty of reflectivity and protection from the heat of the sun. With some special shingles, copper-infused granules are added to prevent the growth of blue-green algae, which is responsible for those unsightly dark streaks you see on some roofs.

Shingles shed granules throughout their lifespan, which can be up to 20 years or even longer when maintained regularly. However, when the majority of the granules have fallen off due to age or a particularly strong storm (a hailstorm can even knock granules off healthy shingles), it’s time to call your contractor for an inspection. When your roof has shed most or all of its granules, your contractor will probably inform you that the end of your roof is near. Your shingles have no more protection from the sun and are likely to suffer damage in a short time.

Ganser Company is an exterior remodeling contractor. We offer virtually all types of exterior home improvement services. We can tell you more about how your roofing shingles are made. Call us today at (608) 222-1243, or fill out our form for a quote.