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Concrete Reinforcement

Level 4 Reinforcement


Green Umbrella® Fi-Flex™ is a variable dose, insoluble, secondary reinforcement concrete fiber uniquely designed to enhance flexural strength and performance. Providing isotropic – three-dimensional – fibrillated fiber reinforcement with a strength comparable to Welded Wire Mat (WWM) or light rebar without the potential for failure due to alkali or corrosion. The even dispersion promotes an impermeable concrete that is resistant to concrete cracking due to fatigue, enhancing post-crack flexural performance. A secondary reinforcement with equal strength to WWM, Fi-Flex reinforces without the need for large mats or light rebar materials, freight, labor, and installation or potential vapor barrier damage due to puncture. Place and finish crews no longer have to maintain full-field steel reinforcement, re-tying bars, or re-setting chairs. Attack crack formation and reinforce the concrete matrix with doses starting at 3lb per c/y.

The next generation of reinforcement

Green Umbrella

& Fi-flex

Green Umbrella Fi-flex™ is a uniquely designed concrete fiber that can be used as a powerful reinforcement.

Fi-flex is a true replacement for wire mesh, mats, and rebar to reduce cracking due to stress on the slab. It provides three-dimensional reinforcement throughout the concrete. 

Fi-flex is a multi-stranded mat fiber that displaces evenly. It doesn’t clump or protrude, making it transparent in the mix, it does not affect the final look.

Cut Your Labor

Reinforcement in the mix.

Comparable to introducing a wire mesh mat and rebar from the mixer. Instead of spending hours tying metal and mesh reinforcement on the ground, Fi-flex is reinforcement in the mix.

Cut Your Downtime

Repair time dramatically reduced.

The time spent returning to cracks for repair is dramatically reduced/eliminated. After the pour and finish, a project moves forward without having to set aside time to repair punctured vapor barriers, cracking due to mat misplacement, or plastic cracking.

Cut Your Environmental Impact

Material Reduction

Less manufactured materials are needed. For example, fewer heavy metal mats and rebar are used, meaning less industrial waste and transportation pollution.

Compression Tests of Concrete Cylinders

Isotropic reinforcement means fiber reinforced concrete is stronger from top to bottom.

Fiber Reinforced Concrete

  • Top 62% 62%
  • Middle 75% 75%
  • Bottom 87.5% 87.5%

Conventional Concrete

  • Top 25% 25%
  • Middle 50% 50%
  • Bottom 87.5% 87.5%


Green Umbrella Fi-flex is a uniquely designed concrete fiber that can be used as a powerful reinforcement.  Fi-flex can be used as a replacement for wire mesh and rebar.


• Enhances performance & durability
• Provides secondary reinforcement
• True replacement for rebar
• Alkali resistant & non-corrosive  
• Mixes well in concrete
• High impact resistance
• Excellent finishability

Additional Features & Benefits
• Fi-flex added to concrete mechanically locks in the fresh concrete matrix, controlling plastic shrinkage.
• Fi-flex provides secondary reinforcement which helps eliminate crack formation that causes permanent weakening of the resultant concrete.
• With Fi-flex, concrete is less permeable, has a smooth surface, is highly impact resistant and improves your Bottom Line.
• Replaces 6 x 6, W1.4 x W1.4 (8 gauge welded wire fabric) and in some cases rebar
• Fi-flex is even better than N 200 due to ionic bonding
• Meets requirements for ASTM C1116/1116M, Section 4.1.3 & Note 3.
• Also meets requirements of ICC ES AC32 Section 3.1.1 & 3.1.2
• Increased fiber-count and improved residual strength
• ARS [Average Residual Strength] of over 50 psi

Wire mesh doesn’t effectively reinforce unless placed in the proper section of the concrete. Isotropic fiber provides secondary reinforcement throughout. 

Learn more about our products

Product Download

Fi-flex Technical Data Sheet
Fi-flex Safety Data Sheet

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