Fiberglass rebar and steel rebar each bring their own strengths and weaknesses to the table, and which one counts as “stronger” really depends on the specific application and requirements.
Fiberglass rebar, also known as glass fiber reinforced polymer (GFRP) rebar, weighs less than steel rebar and won’t rust or corrode — making it a natural fit for environments where corrosion is a concern, such as marine settings or structures exposed to deicing salts. It also delivers high tensile strength and is electrically non-conductive, an advantage in certain applications.
Steel rebar, on the other hand, is typically stronger in raw tensile strength than fiberglass rebar. It also has a much longer history of use in construction, so its mechanical properties are thoroughly understood and documented.
So whether fiberglass rebar counts as “stronger” than steel rebar comes down to the project’s specific requirements — environment, structural load, and desired longevity all play a role. In some cases, fiberglass rebar holds a clear advantage over steel rebar; in others, steel rebar remains the more suitable choice.