WHY IS A CONCRETE SURFACE PROFILE SO IMPORTANT?

Posted by Ryan Spotowski and categorized under Commercial Concrete Polishing, Concrete, Concrete coatings, concrete coatings, concrete surface preparation, concrete surface profile, edmonton concrete, edmonton concrete coatings, and edmonton shotblasting

A few years back, we had a blog post on concrete surface profiles, explaining the differences between them. You can find it here. However, we still have people wondering why is a concrete surface profile so important? There are many reasons to mechanically abrade a floor to create a surface profile, from cleaning the floor to opening the surface of the concrete, but one of the more important ones is to increase the surface area that the material has to bond to the floor.

An infographic showing the difference in bonding area for a coating to a concrete surface with different types of concrete surface preparation

The image above illustrates how the amount of surface area available for a coating to bond to changes depending on the concrete surface profile (CSP) — and while not to scale, it highlights a key concept in surface preparation.

If a floor receives no proper preparation (perhaps just a light wash or sweep), the coating will only bond to roughly the same 10 inches of flat surface. However, when the surface is mechanically abraded, such as with a diamond grinder, the microtexture opens up — increasing the bonding surface to about 14 inches over that same 10-inch span.

Take it a step further with more aggressive preparation, like shotblasting, and the coating now has approximately 22 inches of surface area to bond to across the same length. That’s 2.2 times more surface area than no prep and 1.57 times more than a light grind.

While the figures aren’t to scale, they clearly demonstrate one thing — the more thoroughly you prepare your concrete, the stronger and longer-lasting your coating adhesion will be.

A worker shotblasting a concrete floor using a self-propelled shotblaster

NOT ALL METHODS OF SURFACE PREPARATION ARE EQUAL

Not all methods of surface preparation are the same. Diamond grinding is not as abrasive as abrasive blasting (shotblasting, vaporblasting, and sandblasting are abrasive blasting methods). The International Concrete Repair Institute, ICRI, defines 10 levels of surface preparation. Diamond grinding will create a concrete surface profile of 1-2. Abrasive blasting will create a surface profile of 2-9 (when including shotblasting). If you’re wanting a floor finish that will last, insist on abrasive blasting over diamond grinding.

The more you prepare the floor, the better the bond the substrate will have with the topping.