3 Techniques for Levelling an Industrial Concrete Floor

In serious cases, you might be able to tell that a floor is uneven just by looking at it. But in most cases, you’ll notice other symptoms, such as unstable machinery, before confirming it with a carpenter’s level. Is fixing an unlevel floor worthwhile? And what methods are used to fix it?


The Causes and Hassles of an Unlevel Floor


An unlevel floor may point to a serious underlying problem, such as a sinking foundation. It is important to understand the cause of an uneven floor so that you do not simply put a bandage on the problem. If foundation problems are indeed the root cause of an uneven floor, you will end up wasting money on floor repairs that just don’t last, because the foundation will continue to shift until it is stabilized.


But sometimes an uneven floor has nothing to do with the foundation and everything to do with how it was installed. Unless the original concrete installation team took the time to carefully level the floor, there may be dips and gaps in the floor from their poor technique. In other cases, the floor may be “flat” but gradually slopes in one direction.


But why should you worry about having a level floor in the first place? Is it something you can just live with?


Even if an unlevel floor is not caused by a foundation problem, it’s worth fixing, especially in an industrial concrete floor. A severely unlevel floor can present a trip hazard for workers. Even mildly unlevel floors do not provide the type of stability that large machines require. And finally, a sloping floor makes any type of spill a headache to clean up, if not downright dangerous in the case of hazardous materials.


Finally, if you plan to install bricks or tiles, the subfloor must be level or the tiles and bricks will be prone to cracking.


Using Levelled Wooden Rails as New Concrete Form


The first option uses a tried-and-true method that is most appropriate for smaller spaces that need a tune-up. It involves cutting long wooden boards to match the existing contour of the floor on one side, and then cutting the other side of the board to make a perfectly level straight edge. For best results, multiple boards should be laid out and secured to the floor in a way that allows the screed, or concrete levelling tool, to always touch two boards at the same time.


Once new concrete is poured in and around the boards until it just covers the top of the boards, the screed is used to level the concrete, using the wooden rails as a guide. Because all of the rails are confirmed to be level, the concrete itself will also be level once the excess is scraped away with the screed.

Grinding Down High Spots


If the main problem seems to be that there are high spots on an otherwise even floor, carefully grinding down those high spots can provide a quick fix. Of course, the key word is “carefully,” because if you take too much off, you’ll be dealing with a floor with low spots instead.


To identify high and low spots, systematically use a carpenter’s level or straight edge all around the floor, marking high and low spots with chalk. Grind down the high spots and then check the floor again.


Using a Self-Levelling Compound


Perhaps the most popular technique is to use a self-levelling compound. This is a chemical mixture that settles into low spots and helps achieve a flat, even and level surface.


Before using a self-levelling compound, it’s essential to prep the area by grinding away obvious high spots (you will use less product this way and save money), vacuuming away all dust and debris, and applying a coat of primer to ensure that the self-levelling compound adheres to the concrete floor.


Then pour the self-levelling compound onto the floor and spread it into all corners with a trowel. Wait to let it settle and dry before applying another coat, if needed.


The technique you ultimately choose to level your industrial concrete floor will depend on the size of the floor, your budget and the exact problem you wish to address, but these three techniques are the most common for fixing unlevel floors.