Why Are My Shingles Losing Their Coating?

If you read my last post, you should understand why it is so important to keep the granular coating out of your gutters. However, it can be difficult to do if your shingles are losing a significant amount of their coating prematurely. If you’ve noticed an unusual amount of granules or debris being washed out of your gutters after a storm, granules scattered about your home, or accumulations in your gutters you may be wondering what the cause could be. There are several things to consider that may be contributing to the problem you are experiencing.

The ceramic granular coating on an asphalt shingle does not just give an aesthetic value to the roof of your home. The coating provides protection to the organic layers of your shingle from the UV rays of the sun. If the ceramic coating were not present, not only would the shingle not have a nice texture and color, but it would degrade rapidly, become brittle and fracture. This is important to prevent because it is the asphalt layer that provides the waterproofing ability of the roof. If your shingles are losing their coating, it can cause a significantly decreased lifespan and necessity for premature replacement of your roof.

The granular coating is embedded into the asphalt of the shingle during the manufacturing process. In most cases it holds tightly in place for many years, however if a problem occurs during the manufacturing of the shingle, it can lead to a weaker bond between the asphalt and the granules. Lesser quality shingles can also lose their coating faster than others. It is important to identify the shingle type, manufacturer, and date of production of your shingles, and to keep track of that information in case of a future claim against the manufacturer for defects.

The quality of the shingle and the manufacturing process are not the only factors effecting the ability of the asphalt to bind to the granules. Physical damage can occur to the shingle by mishandling, carelessness, extreme temperatures or weather-related events. Hailstorms are a common cause of premature degranulation. Sometimes, the damage caused by hail is not evident from the ground until several years after the storm. The hail often will loosen the granules, but it takes time for them to separate and wash away after the storm.

One of the most common causes of granular loss is something much less understood by builders and many roofing professionals. Improper attic ventilation and insulation can create a significant effect on the lifespan of the roof. If cool air in the attic space cannot circulate from the eaves of the home through the ridge, box or gable vents in the upper portion of the roof, the shingles and roof deck will overheat.

The extreme temperatures on the roof in the hot summer sun causes rapid deterioration of the shingle by loosening the granules from the asphalt. It is important to properly install even ventilation and keep insulation from blocking the vents, or to climate control your attic space to ensure overheating of the singles does not occur.

Sometimes it takes a trained professional to accurately assess the cause of premature granular loss. If your shingles are losing their granular coating at an excessive rate, you may want to contact a professional roofing company like Roof It Right, LLC in Louisville, KY to help you assess the cause. Sometimes it can take a trained eye and experience to identify the likely culprit. We are happy to assist you with a free assessment of your roof’s current condition and maintenance needs.