Fiberglass and Asphalt Shingles

Fiberglass and asphalt shingles are related as the core, or base material in asphalt shingles may be either fiberglass mat or organic felt.

Generalized, there are two main types of asphalt shingles, each of which consist of a core material that is coated with asphalt, and then covered with granules, thus the name asphalt shingles.

The core material, or base material, may be either of the fiber glass mat or organic felt type.

Shingles made of each type of base material have specific characteristics that suit better for particular projects.

As for fire resistance, the fiberglass asphalt shingles do have a Class A fire resistance rating from Underwriters Laboratories (, UL), the highest of the fire ratings available.

Fiber glass shingles are so called because they have a core of fiber glass reinforcement.

The asphalt coating on such a shingle is applied directly to the core and protective granules are embedded into the coating.

Since the core is not saturated with asphalt, the fiber glass shingles are lighter in weight than organic shingles.

The quality of fiber glass used in the asphalt shingles does vary widely.

There is, however, a test to establish the quality of such shingles, from the American Society for Testing and Materials (ASTM), called ASTM D3462, a "Standard Specification for Fiber Glass Asphalt Shingles."

The test measures force, in grams, required to break a shingle in a measuring device.

Finally, keep in mind that because organic shingles were developed before fiber glass shingles, the term "asphalt shingles" is often used to reference organic shingles only, although both are categorized as asphalt shingles.

From Fiberglass and Asphalt Shingles page to Asphalt Guide index