How Do I Apply A Concrete Overlay?
How Do I Apply A Concrete Overlay?
Concrete floors are often utilitarian, but they, too, require a facelift from time to time. Concrete’s appearance and functionality are harmed by scaling, spalling, checking, and mildew.
The concrete isn’t always level or smooth because of improper pouring. If the floor is technically intact, but the surface is unsatisfactory, there are alternatives besides breaking it up, pulling it out, and beginning over.
Consider putting in a concrete overlay. On top of an existing floor, you may install a concrete overlay with a 1/16-inch ornamental layer or even a several-inch-thick concrete slab. When installing a concrete overlay, you normally have two options for tools.
A typical float has circular ends and a flat or slightly rounded centre.
The float allows you to push and pull concrete in a thin layer as needed to spread it across a large surface.
Another tool looks more like a trapezoidal squeegee. Some refer to this as a “magic trowel” or “knockdown knife.” It has a flexible blade and requires a little practice to operate.
The two tools provide distinct results, which decide which you should choose. The magic trowel works similarly to how you apply a skim coat of plaster or mud with a trowel to apply a thin coat of concrete.
Getting Ready To Apply Your Concrete Overlay
The first step is to clean the current floor using an appropriate detergent. After applying with a push broom, pressure washes the concrete. Then, using an acid designed for concrete resurfacing or diluted muriatic acid, profile the current floor.
Use a push broom to apply the acid, and wear protective gear and respiratory and eye protection. This is especially critical if you intend to add a thin concrete overlay rather than fresh slabs.
Consider using a densifier such as these to make the concrete less porous. Densifiers keep moisture from penetrating the existing floor. A concrete densifier is a chemical applied to a concrete surface to plug pores. This raises the density of the surface.
Following that, you’ll want to repair any major spalling or scaling. These are regions that lack significant pieces of material and must be filled. Making sure the current floor is level, and smooth will result in a better-finished product. As with the acid resurfacer, this is more noticeable when a thin concrete overlay is applied over a fresh slab.
Use a bonding agent as necessary. This phase is debatable among experts, although the difference is most likely due to the smoothness or roughness of the concrete you’re resurfacing. Rougher surfaces often do not require a bonding agent.
Apply The Concrete Overlay By Pouring And Floatting
Then comes the part you’ve been looking forward to pouring and applying the new concrete overlay on top of your existing surface. This might be anything from a floor to a sidewalk to a concrete countertop.
Thinner, ornamental overlays may contain resins or other additives that necessitate further priming (or even two prime coats).
Use a float, trowel, or concrete brush to level the wet concrete. As previously said, various tools might produce different results.
It all depends on what works for you and the style you want to attain. The key to applying an overlay is to obtain a beautiful, level coat. You should also ensure that the fresh coat penetrates into the corners and edges, completely covering the previous surface.
Otherwise, you risk having a highly inconsistent look at your product. We usually begin at the perimeter and make our way inward toward the space behind us.
This ensures that we don’t find ourselves in a bind and makes the most effective use of the material since you have a solid sense of how much extra mixture you would need to finish the work.
After The Concrete Has Settled
After the fresh concrete has cured, sand or scrape the floor until it is smooth, smooth the surface with a diamond disc or a concrete scraper to the required smoothness, or prepare for the second coat if necessary.
Most of the time, this is using a floor sander or a similar equipment to remove any ridges and level the surface in preparation for any final coating.
When sanding a product designed for a multi-coat process, it is common to need to reprime after sanding.
Then finish off with the last coat. When repairing a driveway, walkway, or patio with new concrete, you normally finish with a brush or other means of creating a lovely smooth, completed surface.
Finally, you should seal the new surface. A sealant ensures that the new surface will last for many years.