How do I prepare a concrete surface for applying epoxy?

An epoxy floor is a wonderful option for creating a beautiful finish to your basement, garage or kitchen floor. It has several advantages such as its durability, its ease of cleaning and of course, its look! But before embarking on the application, a crucial step is necessary: the preparation of the concrete.

How to prepare your concrete slab?

Grind the concrete

The first step is to grind the entire surface that will be covered. This will allow mechanical bonding between the epoxy or polyaspartic and the concrete. If this step is done incorrectly, the epoxy could come off the floor and the application will have to be started over.

So you need to make sure you are using the right tools to do this task.

If your concrete is porous, that is, there is concrete dust when you touch it, or the concrete has been flattened by hand, you should sand it with diamond wheels.

Alternatively, if the concrete is closed, i.e. not dusting or has been machine flattened, you must use a Blastrac Shot Blasting or a Bush-Hammer type blade. You can make the perimeter with diamond wheels.

Clean the surface

Officially, after grinding your surface, there is going to be dust on your concrete. You definitely don't want to apply directly on the dust, it will ruin your project.

You must therefore vacuum in order to obtain a clean surface, ready to receive its first coat of epoxy.

Attention! Never use water to wash your slab. Water and epoxy are not compatible and you will not be able to apply if your concrete is too wet.

Check the humidity

Finally, before applying your first coat of epoxy, you must check the humidity of your concrete. If your concrete does not meet the recommended values of less than 4% humidity, this could create problems during application since water and epoxy are not compatible. A moisture resistant epoxy is available if you cannot get your concrete below the required 4%.

Apply

Before applying, ensure that the temperature is around 22 to 30°C so that the working and drying time complies with the technical data sheets. The product still works outside of this range but it may take longer or shorter to dry. Also, it is important to deactivate heated floors 24 hours before application.

Congratulation! You are now ready to apply your first coat of epoxy or polyaspartic to your concrete slab. Stay tuned, new articles explaining how to apply for metal, flake or quartz floors will follow soon.

Note that all machines or tools mentioned in this guide are available for sale or rental in our stores.