What Is The Difference Between FRP And Fiberglass?

A: Fiberglass is a very generic term and can mean a wide variety of different products. FRP stands for fiber-reinforced plastic. Generally, it’s a term used for our type of fiberglass—grating, structurals, and the like.

If you do a Google search for fiberglass products, you may find the terms “fiberglass and “FRP” used interchangeably.  Honestly, if you don’t know what they are talking about, it can be quite confusing trying to distinguish between the two. One way of thinking endorses that there is no difference between fiberglass and FRP.  Those that follow this line of thinking claim that FRP is simply a marketing term.  A better way of sorts to describe a more advanced form of fiberglass. They contend that fiberglass and FRP are in fact, the same.

However, if you dig into the technical specifications of fiberglass and FRP—that’s just not accurate. FRP would be better described as a more advanced form of fiberglass.


In technical terms, you create fiberglass by spinning melting glass in such a way that it creates fibers of glass.  In and of itself these fibers can be a usable product, but more often than not fiberglass is used in a composite.

A composite is a combination of materials that when combined, create a new substrate.  The composite is often comprised of a matrix or base material and reinforcement material.  The matrix can be metal, plastic, or even ceramic. Fiberglass, in this case, is the reinforcement material that makes the composite stronger than the parts on their own.

Most just call the resulting composite “fiberglass” since no matter the base, fiberglass is used for reinforcing it.  Today, many companies are trending towards calling plastic-based composites “glass-reinforced plastic.”  This is due to the usage of plastic or variations of plastic such as vinyl or polyester. The term “GRP” distinguishes this product from “FRP” by changing a key word. Confused yet? Read on.


FRP is an abbreviation for fiber-reinforced polymer. Not to get too scientific, a polymer is a chemical compound with a long chain-like structure of molecules.  Some polymers are natural like rubber, others are synthetic such as polypropylene.  Pliable synthetic polymers such as polypropylene are called thermoplastics while more rigid ones such as polystyrene are called thermosets.

The polymer matrix can be reinforced with many different kinds of fibers depending on the purpose of the final product. The fibers used can be glass as in fiberglass, or it can also be carbon or graphite such as in the auto racing industry.

Because the fibers in FRP aren’t necessarily glass, not all FRP is GRP but all GRP is FRP—surely you must be confused now.  It comes down to the designation of the fibers used, GRP uses glass in the form of fibers. Therefore, it is both FRP and GRP since it does use fibers. However, a polymer reinforced with carbon would only be an FRP since the fibers used are carbon not glass. Kind of like all dogs are canines but not all canines are dogs—canines also include wolves, coyotes, and foxes.


FRP products like grating and structural pieces from DEFI are used more and more in all industries.  Especially with construction and manufacturing, FRP is seeing a huge surge in usage due to it being lightweight but incredibly strong. In fact, in some situations, it’s up to seven times stronger than steel and is corrosion resistant.  So, you see, fiberglass and FRP really are technically different when you break it down but they are the future of industrial structures.


No matter the industry you are in, DEFI FRP products can play a vital part in increasing the safety of your operation.  Not only keeping your workers safe but also keeping long-term operational costs down. Contact us today to see how we can implement our FRP products into your operation.

Recent Post

Get Connected