Shingles used in roof replacement.

What Fiberglass Shingles are Made Of 

Have you ever thought about what goes into the shingles that go onto your roof? Shingle technology is what enables your roof to last up to 20 years, despite the sun, rain, and wind. Although fiberglass shingles, often called asphalt shingles, are the most common roofing material used in Minnesota, they are hi-tech engineering.

The Fiberglass Base

In the old days of shingle manufacturing, shingles were made by saturating cellulose with asphalt. This wasn’t very durable. So, for the past few decades, the standard has been to use fiberglass. Each shingle’s base is a mat of uniformly dispersed fine glass fibers held together by a binder. This fiberglass mat must be strong enough to last the guaranteed lifetime of the shingle. This mat is the foundation upon which the other layers of the shingle will be built.


This mat is saturated with hot asphalt until all the fibers are coated. In the past, shingles were made using a blown asphalt layer. Asphalt makes the shingles waterproof, adds to the shingle’s strength, and holds the granules in place. Today, with advanced roofing technology, asphalt products have changed. Shingles are made with an asphalt compound known as styrene-butadiene-styrene. This adds to the material’s durability and resists impact while still performing its original job of keeping granules on and water out.

Mineral Granules

The topcoat is a variety of refined, opaque ceramic-coated minerals made from crushed rock. These granules are pressed into the asphalt, where they are held firm. They protect the roof from the sun’s ultraviolet rays, as well as make the shingles resistant to fire damage. The colors can be chosen to compliment your home’s exterior.

Because the loss of granules can compromise your roof’s integrity, manufacturers usually add 40% more of this coating to your shingles than is needed. This prevents excessive granule loss during installation.

Shingle Backsurfacing

Each shingle’s back surfacing is coated with slag fines or sand to keep the shingles from sticking to the fabrication line and other machinery during manufacturing. This also prevents shingles from sticking together in storage,

The Most Important Part of Getting a Good Shingle

Although we often take it for granted that our roof will keep us dry, there is a lot of engineering that goes into making that happen. And the technology seems to be improving every few years. That’s why it’s essential to have a roofing company you can trust. All Craftsmen Exteriors only uses the highest quality materials on our customers’ homes. Whether you need storm repair or a total replacement, Contact us today!