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Properly Cleaning Concrete Will Ensure Your New Concrete Overlay Lasts For Many Years

Applying a Concrete Overlay to your existing cement floor will make your floor look as if it were just poured. You will have many options with what you can create including stamping, staining, texture or you might just want the look of new smooth concrete. If applied correctly and measures are taken to perform proper preparation, your new overlay should last for many years. Preparation is very important with this process so by taking a little time to understand the correct procedures for installing concrete overlays, you will be much more satisfied with the results.

First and foremost, your old concrete floor needs to be prepared properly. Otherwise you will not achieve proper adhesion between your old concrete and the new overlay cap. Start with the chips and cracks that are in the old floor. A variety of products are readily available to fill chips, low spots and cracks from your local home improvement store and we also offer professional grade products for this purpose. I would highly recommend not cutting costs here, spend a little more and purchase professional grade products and you will be happier with the lasting results. In most cases, our professional T1000 will do a great job of filling cracks and low spots. Follow the manufactures instructions for the product you are using, making sure that you allow the filler to completely cure.

The floor will need to be completely cleaned before you you apply the overlay material and Cleaning Concrete can be achieved using different methods. As a general rule, the old concrete needs to be thoroughly cleaned and roughed up as part of the preparation process. This can be accomplished using two different methods. Simply cleaning concrete will not be enough, you will need to use Muratic Acid to etch the cement or better yet, you will need to grind the concrete using a concrete grinder or Lavina Machine.

Both of these pieces of equipment can be rented from your local equipment store. Using Muratic Acid to prepare the floor is the least expensive method but may not be as effective. This depends on the condition of the floor. If the floor has old sealer, glue, paint, adhesive or oil, a grinder will be necessary. But if your floor has none of the above and is in relatively good condition, then you can just use acid to clean the concrete. This procedure is fairly simple, all you need is Muratic Acid, an inexpensive garden sprayer and Ammonia.

After you have repaired and thoroughly cleaned the concrete, ventilate the area your working in and make sure that the temperature is at least 50 degrees ambient. Mix four gallons of clean water to one and a half gallons of Muratic Acid and mix thoroughly. Spray this mixture on the concrete floor completely wetting the entire surface and immediately neutralize the floor using two cups of ammonia to four gallons of water. If possible, pressure wash the entire area using a 3500 PSI sprayer. If you cannot power-wash the surface, use a Wet-Dry Vac to remove standing water.

Before the floor is allowed to dry, apply your primer, (I recommend our T1000 for this) and apply a thin coat by rolling it. After the primer coat has been allowed to dry, mix your Concrete Overlay material (again I recommend our T1000 for this) at the recommended rate and wet the concrete surface. Apple the overlay using a trowel at approximately 5/16" thick and use a Gauge Rake for uniformity. The overlay will begin to feel soft, almost like a marshmallow when it's ready for stamping and texture.

If you're using stamps, apply liquid release agent to the surface and begin the stamping process by laying the stamp on the moist Concrete Overlay material and pushing the stamp into the overlay. Rolling is basically the same procedure. When you're finished, use touch up rollers to dress up any areas that the stamp did not completely impress. If your mortar line has concrete slag in them after the concrete overlay dries, use a Chisel to clean the joint.

If you're planning to not stamp the new overlay, you can trowel the new cap or texture to your liking. You can also add color to the new overlay prior to installing it which gives the look of new concrete. Concrete Equipment Direct has all of the information and supplies to help you get this task finished!