Polished concrete floors are one of the most beautiful and long-lasting decorative techniques for your home or business. They create a smooth, shiny surface that requires little maintenance.
However, polishing concrete is no simple task. It requires the skills to use heavy, dangerous and expensive machines and generates tons of concrete dust and loud noises.
This project is out of the scope of most DIYers. But, if you’ve got access to tools, cleaning supplies, and plenty of time and want to risk injury or damaging your floor, we’ve outlined the process in this article.
Step 1: Prepare the Concrete Surface
Preparing the floor for polishing begins with removing debris, dirt, or stains from the concrete’s surface. Do this by sweeping or vacuuming the area and using a concrete cleaner to remove stubborn stains.
Also, cracks or holes in the concrete must be filled with a patching compound to create a flat surface. Once the surface is clean and you’ve repaired all the damage, you can move on to the next step.
Step 2: Grinding
Grinding removes rough or high spots, creating a smooth, even surface. You’ll want to rent an industrial push grinder for large floors, but you might get away with an angle grinder for closets or small bathroom floors.
Start off with a coarse grinding wheel and gradually work up to a finer disc, about 80 grit, to achieve a smooth finish. The deeper you grind into the surface, the more aggregates you’ll expose.
Protective gear is critical while grinding. Always wear gloves, boots, safety glasses and a respirator. It produces a lot of dust, and you might want to wet the surface to keep some of the dust down.
Step 3: Honing
Honing is a pre-polish grinding using 100 to 200-grit abrasive pads. If you only need a low-sheen or non-slip surface, you don’t need to move on to fine polishing.
Step 4: Densifying
A concrete densifier penetrates the surface, helping it resist scratches and impacts. These chemicals react with the concrete and close the top layer of pores, which makes it easier to polish and prevents dust shedding.
Apply the densifier liquid with a sprayer and work it into the surface with a brush or broom. The floor should stay wet for 15 minutes while the chemicals react. Add more densifier if the surface dries before.
Step 5: Polishing
For polishing, you’ll use 400 to 3000-grit diamond abrasive pads. As you move higher into grit levels, you’ll create progressively finer scratches that eventually turn into a glossy finish.
Use each higher grit in succession over the entire surface. The smaller sizes will erase the previous grit’s scratches, but skipping a level leaves blemishes on the floor.
Step 6: Seal the Floor
The final step is to add a sealant to the concrete floor. Penetrating or topical versions are available, but true mechanical concrete polishing always uses a penetrating sealer.
Sealants protect the surface from moisture and add colour. You might also choose to burnish the floor to remove excess sealer.
If you have questions about concrete polishing in Ottawa, give us a call. Ottawa Concrete Polishing is your concrete restoration expert!