Synthetic Microfibers
FiberForce 100
Ultra-fine denier microfiber
FiberForce 150
Fine denier microfiber
FiberForce 300
Fibrillated microfiber
FiberForce 350
Ultra-fine denier fibrillated microfiber
Fibrillated microfibers
What Is Microfiber for Concrete?
Plastic shrinkage cracking can develop in the first few hours after a pour, while concrete is still plastic and surface moisture is evaporating faster than bleed water can replace it. Wind, low humidity, high concrete temperature, and direct sun can accelerate that moisture loss. The resulting cracks can compromise appearance and create additional durability concerns in exposed slabs.
Synthetic microfiber controls early-age cracking. Monofilament or fibrillated fibers distribute through the mix and help limit plastic shrinkage and plastic settlement while the concrete develops strength. Macrofiber serves a different purpose: post-first-crack reinforcement. See our macrofiber page if you are evaluating an alternative to welded wire reinforcement or light reinforcing steel.
Monofilament vs. Fibrillated Microfiber
| Monofilament | Fibrillated | |
| Products | FiberForce 100, FiberForce 150 | FiberForce 300, FiberForce 350 |
| Fiber structure | Single continuous filament | Network/mesh structure that opens during mixing |
| Finish | Excellent finishability, minimal surface fibers | Smooth finish comparable to monofilament (FiberForce 350) |
| Best for | Residential slabs, decorative concrete, pool decks | Slabs needing WWF replacement + shrinkage control |
| Notable trait | Substantially reduces explosive spalling | Enhances impact, pullout, and abrasion resistance |
Dosage Guidance
| Product | Dosage | Notes |
| FiberForce 100 | 0.5 lb/yd³ | Ultra-fine, residential-focused |
| FiberForce 150 | 1.0 lb/yd³ | Substantially reduces explosive spalling |
| FiberForce 300 | 1.5 lb/yd³ | Replaces 6x6-W1.4xW1.4 WWF depending on application |
| FiberForce 350 | 0.5–1.0 lb/yd³ | Meets/exceeds monofilament performance at 0.5 lb/yd³* |
*Local building codes may allow the reduced 0.5 lb/yd³ rate for plastic shrinkage mitigation only — confirm with your local building official before specifying at this rate.
Application Examples
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Bridge decks and elevated slabs — exposed to wind and rapid moisture loss during the pour, both accelerants for plastic shrinkage cracking.
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Water retention tanks and pool decks — surfaces where hairline cracking creates a direct moisture-intrusion risk.
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Residential slabs, driveways, and decorative overlays — where finish quality is as much a spec requirement as structural performance.
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Shotcrete and precast — applications with high surface-area-to-volume ratios, which dry faster and are more crack-prone during cure.
Frequently Asked Questions
What is synthetic microfiber used for in concrete?
Its primary use is plastic shrinkage crack control during the first hours after a pour.
How is microfiber different from macrofiber?
Microfiber midigates early-age plastic shrinkage cracking during curing. Macrofiber provides post-first-crack structural reinforcement and is dosed at a much higher rate (3.0+ lb/yd³ vs. 0.5–1.5 lb/yd³). Many slab systems use both together — see our macrofiber page for the structural side.
Can microfiber replace welded wire fabric (WWF)?
What dosage rate of microfiber do I need?
Is microfiber suitable for residential concrete?
How is microfiber added to concrete?
Microfiber is introduced into the concrete mix according to the product instructions and project specification. Find a FullForce representative to coordinate dosage and batching with your supplier.