Common Causes of Asphalt Shingle Granule Loss

Mineral granules on asphalt shingles are as structurally important as they are aesthetically. More than just providing distinctive colors, they protect the material from ultraviolet radiation, which causes chemical changes in the asphalt.

Common Causes of Asphalt Shingle Granule Loss

While it’s normal for newly installed shingles to shed granules, it’s a cause for concern when they start to go bald. In today’s post, Coleman Roofing talks about the main reasons why asphalt roofing shingles experience loss of mineral granules:

Shingle Deterioration

Aging is the natural explanation. As time goes by, heat causes asphalt shingles to lose volatiles, affecting their bond with their protective granules. This phenomenon doesn’t always occur at the same rate across the board since certain roof sections are more exposed to heat than others are.

If you find granules in the gutters, though, it doesn’t signal the need for immediate replacement. It could indicate that your asphalt-shingle roof has reached midlife. Nevertheless, greater exposure to UV radiation accelerates shingle deterioration.


Coleman Roofing knows that foreign objects can dislodge mineral granules effectively. The impact of hail can knock them out of position, and so does foot traffic. Overhanging limbs can scrape the surface of asphalt shingles as they move with the wind.


Popping blisters can displace granules too. They are caused by moisture penetrating the shingles either during the manufacturing process or due to a poorly ventilated attic. The affected areas are more likely to shed more granules at a faster rate because of increased exposure to UV radiation.

Improper Storage

Roofing materials can fail without experiencing storm damage. When improperly stored ahead of installation, asphalt shingles age more quickly because of the weather. This is especially true when they’ve become rain-soaked while in storage.

Determine the real culprit behind your asphalt-shingle roof’s granule loss to address the issue accordingly. Call Coleman Roofing at (225) 379-7663 now to discuss your roofing needs, and get a free estimate in Lafayette or Gonzales, LA.