GFRC FAQ
What is GFRC?
GFRC stands for "Glass Fiber Reinforced Concrete." It is a Portland cement-based composite with alkaline-resistant glass fibers randomly dispersed throughout the sand/cement matrix. It has a much higher compression and flexural strength when compared to typical (even high-strength) concrete mixes.
Why GFRC?
GFRC is a lighter (due to how thin it can be cast), more durable concrete mix that can be cast into unlimited shapes and designs.
Cast panels and countertops as thin as ¾”.
Unlimited design and color options.
High compressive and flexural strength.
Minimal shrinkage and cracking.
No need to vibrate the mold.
What Is Alkali Resistant Glass Fiber?
Alkali Resistant (AR) Glass Fiber is glass fiber with added zirconium oxide, which helps resist attack from alkalinity. This is crucial because concrete is a very alkaline environment. AR fibers have been widely used in the concrete industry since the 1970s. Glass fiber allows for thinner and lighter-weight concrete, eliminating the need for steel reinforcement. AR Glass Fiber is the primary reinforcement used in GFRC.
How does GFRC compare to precast concrete?
GFRC is both more elastic and denser than precast concrete. The ratio of cement to sand for GFRC is 1:1, compared to 1:3 for typical concrete. The addition of glass fibers to reinforce the surface results in significantly higher flexural and impact strength than precast concrete, as well as lower permeability to water and air resulting in stronger concrete.
How durable is GFRC in cold northern climates?
GFRC is very durable. In freeze-thaw tests, samples showed only slight flaking after 300 cycles, compared to severe deterioration of unreinforced mortar after only 200 cycles. Laboratory tests indicate no surface deterioration after the equivalent of 50 years of service in typical northern U.S. weather conditions. Due to its high density, GFRC also has very low water vapor permeability (~3) compared to other concrete products. This means it's a longer lasting, stronger concrete.
Why is the water measured in weight instead of volume?
Weight is more accurate, especially in large amounts. Also, if you are adding ice, it has a different density so volume wouldn't work, it needs to be weighed.
What is Plasticizer (Water Reducer)?
Plasticizer, also known as water reducer, super-plasticizer, or high-range water reducer, is a chemical that improves the workability of the slurry at a low water/cement ratio in GFRC.
Why choose GFRZ instead of other products?
Our mix is fully blended, requiring only the addition of water (and/ or water-reducer) and glass fiber for the backer coat. Some mixes, like Surecrete and Blendhouse’s Forton VF 774, require the addition of a liquid polymer, which can significantly increase shipping costs and labor time. Other all-in-one blended mixes (such as Trinic and BRCP) may cost more for a similar product, but those companies do not offer the same level of service and consistency that CCS provides. Additionally, it has no offensive odor which is common with other brands due to the type of polymer used.