If you’re doing your own gutter cleaning and found granules in the gutter troughs, they’re from your asphalt shingle roof. In today’s post, roof installation and kitchen remodeling contractor Northwest Construction explains how they get into gutters, what they indicate, and — most importantly — whether or not you should be worried about them.
Asphalt shingles consist of an asphalt-soaked backing material and a layer of protective granules, which are mostly made from crushed rock. During manufacture, the granules are pressed onto sheets of backing material, still wet after soaking in hot asphalt. As it cools, most of the granules adhere to the backing, while some naturally come loose.
The main purpose of asphalt shingle granules is to protect the asphalt layer from damage caused by UV rays, much like certain types of coating applied onto siding. Other types of granules may be blended in during manufacture to add features. For example, copper granules may be added to prevent the growth of blue-green algae on the rooftop.
Asphalt shingle granules are not laminated onto the backing material. This means it is normal to find granules in the gutters during the first few months after installation as the rain washes off loose granules. This should taper off over the next few years and should not be a problem: it’s a normal sign of wear and tear.
This is not to say that you should ignore asphalt shingle granules in the gutter. You should be concerned if the resulting sediment is at least half an inch deep in your gutter troughs, because this indicates increased wear on the roof. Under normal circumstances, granule erosion should only happen if the roof is beyond its expected life span, so you have to inform your roofing contractor if you find it much earlier. Depending on your warranty coverage, your roof may be warranted against premature wear.
Northwest Construction is your leading provider of home improvement services, including gutter installation and bathroom remodeling. Give us a call at (313) 277-7676. You can also fill out our contact form to schedule an appointment. We serve customers in Farmington Hills, Livonia and Canton, MI.