Unlike acid-based stains that react with concrete and change the color through a chemical reaction, concrete dyes penetrate the slab with fine coloring agents. The particles fill the pores, creating a near permanent color. Given how dyes work, we are often asked if concrete densifier should be used before dyeing it. The answer goes beyond a simple yes or no, so we wanted to take the opportunity to provide a more in-depth look.

Measuring How Hard the Concrete Is

The first thing you need to know before applying dye or densifier is how hard the concrete slab is. Use the hardness scale measurement to scratch the concrete surface with four small tools (you can purchase a small tool kit from Amazon for less than $20). The tools are standardized and calibrated according to the Mohs scale to measure hardness and number between 2 and 9.

Use the tools to draw lines that are about two to three inches long in the concrete, and the highest numbered tool that causes a noticeable scratch determines the hardness. If your concrete slab measures a #6 or below on the Mohs scale, you should densify the concrete before dyeing it.

Why Densify Concrete Before Dyeing It

As we mentioned, dye penetrates the concrete and fills in the pores. It shows color by having the dye near the surface of the concrete. Densifying concrete that is already hard means the dye is more likely to sit on the surface and wash or wear away as it’s mopped or with foot traffic. Dyeing concrete that is soft will have the opposite problem. It will seep too deep down into the concrete and won’t be visible on the surface.

Applying a coat of densifier before applying the dye means the concrete will be dense and strong enough to create a harder layer under the surface. This will stop the dye from going too deeply while still providing enough space near the surface to allow it to penetrate and bond.

Shop Our Line of Concrete Dyes and Densifier

If you plan on dyeing concrete, we have a variety of high-quality, long lasting dyes available. These dyes can play up natural variations in color and texture of your concrete and can create a deep, rich saturated tone. To learn more about our selection and determine if dyes, stains, or a combination of both are right for your next project, contact us today at (815)472-9744 or fill out a contact form to get started!