Applying a concrete densifier is a key step in grinding and polishing a concrete floor. One question we’re asked frequently is “Do I need to densify concrete twice or is once enough?” And our answer to that is, “It depends!” We know that’s vague, so to help you determine your best course of action, we’re going to look deeper into concrete densifier, how it works, and how many times you should apply it during the grinding or polishing process.

How Does Concrete Densifier Work?

Concrete is a porous surface that can crack, chip, and wear. Applying a densifier makes the floor more “dense” by seeping into the concrete and undergoing a chemical reaction with the calcium hydroxide which creates calcium silicate hydrate. The crystalline structure within the concrete grows and spreads, acting like a glue to bond the larger and finer aggregates together.

Densifier doesn’t necessarily make the floor harder, but it does make it much more durable. A denser floor that is less porous is going to hold up over time for much longer – it will show less wear and resist abrasion.

Applying One or Two Coats of Densifier

Before you apply a second coat of concrete densifier, check with the manufacturer’s instructions or even shoot an email to their customer service. They know their products best and will give the best possible advice. After all, they want you to get the best results!

However, if you’re debating one or two coats, the rule of thumb is to consider the starting condition of your slab. Is your concrete dense or is it soft and porous? If you’re not sure, you can find out in one of two ways.

For a more precise test, purchase a Moh’s Harness Test Kit for industrial applications – they’re around $100 and available on Amazon. This is ideal for showing an architect or consultant that you’re serious about defining the condition of the slab.

If you just want a general idea of what you’re working with, a house key will work to give you a general indication of density. To use your keys, run one on the surface of the slab – if a shiny streak is left behind, one coat should be fine. If it actually scratches the slab, two coats is a better option.

Contact Us for Concrete Densifier and More!

We carry concrete densifier from Inland, a trusted surface preparation equipment and supply company. Buy your Inland concrete densifier today, or to learn more about our other concrete chemicals and equipment, reach out to our sales team by calling (815)472-9744 or filling out a contact form to get started!