MIX DESIGN

Below are mix design recipes for white GFRC concrete countertops using one bag of Integrity PowerBlend across several common casting methods.

Integrity PowerBlend is formulated with key components already proportioned correctly, helping reduce material waste and simplify batching. 

This video demonstrates how the different mix consistencies behave during placement. Use it as a visual reference for the textures and workability you should expect from each mix design.

Note: The images below illustrate the expected mix consistencies for each casting method. All mix designs recipes below are for white concrete without pigment.

MIX DESIGN 1
FLOWABLE, DIRECT CAST / SELF-CONSOLIDATING GFRC MIX RECIPE

Mix Consistency:
Highly fluid and easily pourable, similar to pancake batter. The mix spreads and levels on its own, allowing air to escape naturally without the need for vibration.

Ideal Applications:
Direct casting into detailed or complex molds, producing smooth, glass-like finished surfaces, and projects where mechanical consolidation is not practical.

Temperature Guidance:
Chill the concrete mixture to below 60°F (16°C) to achieve the best flow characteristics.

Expert Tip:
Higher UltraFlow dosages dramatically increase fluidity, but they also shorten the working window. Keeping the mix cold helps extend working time. Once the concrete begins to set, it will stiffen rapidly.

MIX DESIGN 2
SOFT, SPREADABLE GFRC MIX RECIPE

Mix Consistency:
Thick and cohesive, with a spreadable texture similar to natural peanut butter. The mix holds together well and adheres to vertical surfaces in thin layers without slumping.

Ideal Applications:
Troweled face coats, hand-applied backer layers on vertical surfaces, and situations where a workable paste is needed that stays in place after placement.

Expert Tip:
This consistency is well suited for hand application. It provides a comfortable working window so you can shape and refine the surface without feeling rushed.

MIX DESIGN 3
HAND-PACKED GFRC MIX RECIPE

Mix Consistency:
Softer than pressed concrete but still firm, with a texture similar to quality modeling clay. The mix packs together easily and produces subtle voids and fine fissures rather than large cracks.

Ideal Applications:
Terrazzo face coats, controlled surface textures, and applications that require careful hand placement without disturbing the surface.

Expert Tip:
This consistency packs well without becoming sticky. If the mix feels too dry, increase the UltraFlow dosage in small 0.05% increments rather than adding additional water.

MIX DESIGN 4
STIFF, HAND-PRESSED GFRC MIX RECIPE

Mix Consistency:
Very firm with a dense, clay-like texture that holds its shape during placement. This stiff mix allows for pronounced fissures and strong surface manipulation.

Ideal Applications:
Pressed finishes, bold surface textures, and designs where the hand-worked character of the concrete is meant to stand out.

Expert Tip:
Even without UltraFlow, keep the water ratio tightly controlled. This stiff consistency requires more effort to place and shape, but it produces some of the most dramatic textural effects.

MIX DESIGN 5
SPRAYABLE MIST COAT GFRC MIX RECIPE

Mix Consistency:
Creamy and fluid enough to pass easily through a spray gun while still having enough body to stay on vertical surfaces without sagging or running.

Ideal Applications:
GFRC face coats on vertical or overhead surfaces, producing smooth finishes with minimal pinholes, and projects that require a controlled spray pattern.

Expert Tip:
This mix works best within a narrow dosage range. Too little UltraFlow and the material will not spray consistently. Too much and it may slide on vertical surfaces. Always perform a test spray on a vertical board before applying it to your mold.

This mix is intended for the GFRC face coat only. A structural backer mix with Integrity UltraFibers must be applied afterward using one of the backer mix designs listed above.

MIXING INSTRUCTIONS FOR INTEGRITY POWERBLEND

STEP 1
Dry blend the PowerBlend, pigments, and UltraFlow if needed. PowerBlend already has 0.15% UltraFlow in it.

STEP 2
Add all of the mix water plus ice to a separate mixing bucket. 

For flowable (SCC or direct cast) concrete, always chill your concrete using ice to achieve a concrete temperature of 55°F to 65°F. Chilling your concrete greatly increases working time and improves flowability. 

Please use this chart to determine the amount of ice to use per full bag of Integrity PowerBlend.

STEP 3
Gradually add all the PowerBlend to the water and blend until fully mixed. Concrete made with PowerBlend is most effective when added slowly to your mix water.

• • Start by adding about 1/3 of the PowerBlend and blend until all of the dry material wets out.
  • Add half of the remaining PowerBlend and blend further until all of the dry material wets out.
  • Add remaining PowerBlend and blend until all dry ingredients are incorporated.
  • Scrape the bucket and the mixing paddles well, then mix continuously on medium to high speed for no less than 2 full minutes. This is most important for flowable SCC/direct cast mixes.

STEP 4
Add fibers last. Gradually add the fibers to prevent clumping and mix slowly to prevent whipping air into the mix. Ensure the fibers are fully wetted out and well dispersed throughout the mix. Do not mix on high speed.