Substrate Technology
+1 (815) 941-4800
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1384 Bungalow Rd.
Morris, Illinois, U.S.A.

When you have a project to polish concrete, you want it to maintain its beauty and shine for as long as possible. In order to do this, grouting the concrete in between polishing pads is a necessary step. Learn the steps to using grout pans to fill in voids and micropits or watch the video below to get started.

Why Is Grouting Concrete Important?

Grinding concrete opens the slab and creates a scratch pattern. While polishing it with gradually finer pads does smooth away many of the cuts, there are still going to be pinholes and micropits left behind. If you apply an epoxy coating, air bubbles will be caught in these voids and prevent the coating from bonding to the concrete properly. If left unsealed, grit and traffic will continually cut and grind into the voids, making them larger. Either way, these nearly invisible flaws will grow over time and ruin the look and structural integrity of your slab.

By applying a coating of grout over the concrete, the air is pushed out of the pits and fills them, allowing you to continue the polishing process or apply a coating.

How to Grout a Concrete Slab?

After using your coarse to medium-grit diamond pad, you need a smooth, clean surface to work on that is free of contaminants. Vacuum any dust or clean up the slurry, then apply a skim coat of 100 percent solids epoxy taking care to press it over the pinholes and pits.

Once the epoxy is applied but it’s still wet, apply a generous coating of marble flour to the slab. Put your grout pans on your floor grinder and the pans will mix and press the grout coating into the surface, filling the voids and pressing out the air. Let it cure for six hours or overnight before continuing with the grinding and polishing process.

Marble Flour or Concrete Dust

Customers often ask us if they can use concrete dust from the dust collector to grout the floor. We do not recommend this because concrete dust is contaminated with dirt, chunks of concrete, and other pieces and particles, so it won’t bond into the pits and voids. Marble flour is very smooth, even, and free of contaminants so it provides reliable results.

Purchase Floor Grouting Materials Today

When you need diamond pads, floor grinding machines, and more, we have what you need to get the job done right. Reach out to a member of our team today at  +1 (815) 941-4800 or fill out our contact form.