Concrete surfaces contain numerous minute pores after hardening. The pores depend upon the application of vibrator, surface compaction, and also the surface texture of firm work.
So, when paints are applied to the concrete surface the pores absorb the paint on the surface to some extent(yo the depth of millimeters). And it’s extremely difficult to remove paints in comparison to other smooth surfaces like metals, wood.
how to remove paint from concrete floor?
Thus removal of paints from concrete surfaces generally involves following process or steps.
- Cleaning of the painted surface of the concrete where the paint is to be removed. The initial cleaning generally includes the rinsing of the surface with water or soap water and scrubbing it with the steel bristle brush as much as possible to remove the paint from the surface.
- After that, the concrete surface is left to dry. And the remaining scrapper pieces of paint are detached with help of a wall putty plate or sandpaper.
- If still the paint is not completely removed then the surface is applied with the paint stripper. Paint strippers are specially designed chemicals to removing the paints from the surface. The paint stripper is usually available differently for each type of paint. So one must carefully choose the correct respective paint stripper for easier working. If the type of paint is not distinctly known then, people prefer oil-based paint stripper to choose.
- So paint strippers are applied throughout the surface of concrete and then left for 6-8 hours. During this time the chemicals of the paint stripper react with the residual paint and thus break down the adhesion of the paint from the surface.
- The paint stripper and remain of residue are then rubbed or cleaned with help of a steel bristle brush and scouring powders once more. The process needs lots of manpower and consumes time, so it is preferable to use the pressure washer jet for a larger surface area to be cleaned. The pressure of the jet should be maintained at 206 bars for the best results.
- If the paint still hasn’t been completely gone, then the process of applying the paint stripper and removing it is again repeated till the desire clean surface is obtained.
This is the general procedure for removing the paints from the concrete. However, the removal process might differ from the types of paints and the required type of paint stripper.
On the basis of the working mechanism or the active components, the stripper is generally divided into two types. They are, Caustic and solvent-based. Caustic paint stripper is based on the mechanism of hydrolysis o break down the paints whereas solvents are based on the swelling of the paint in order to loosen the bonding and thus making it easy to peel off.
The chemical activator and inhibitor are also used with paint stripper to make the process effective and rapid. Chemical-based stripper like soy-based gel cleaners, mineral spirits are effective but the costlier ones.
The DIY paint stripper is used for the tough spots, along with the use of thinner to peel the layer of tough paint without dissolving and disintegrating paint.
Some super absorbent paint strippers are used along with the mixture of clay so that the paint stripper remains trap inside clay for a long time and the mix can develop a series of chemical reactions with the paint layer slowly.
These are some popularly used to paint strippers to remove paint from concrete surfaces. The protective wear like rubber gloves, glasses, mask, etc must be kept in mind before handling such stripper.
How to remove latex paint from concrete?
First of all, apply the general procedure for removing the paints. The only moat important thing is to select the type of paint stripper required for the latex paint.
Latex paints are tough paints so it’s better to use the solvent paint stripper so that the layer of latex paints can be easily peeled off. The most common use of paint stripper for latex paint is ammonia due to its easy availability and working.
And also the paint thinners like petroleum solvents, ether, isopropyl, and alcohol also use for the purpose. But their mechanism is based on the swelling rather than disintegrating the paint. However the
How to remove spray paint from the surface of concrete?
Spray paints are very different than latex paints. They are a form of the integration of the very minute droplets of the paints and thus cannot be considered as a monolithic layer.
To remove spray paints the general procedure is applied along with the use of paint stripper as caustic-based paint stripper. They hydrolyzed and disintegrate the paints and that can be easily scrubbed and washed out.
The most common use of paint stripper for this purpose is trisodium phosphate along with water. And also the concentrated solution of caustic soda can be used for this purpose.
How to remove acrylic paint from concrete?
Acrylic paints are water-based paints. So they can be easily removed even with scrubbing and washing by soap water and sanding (using sandpapers) to some extent.
If the quality of acrylic paint is too high then water-based solvent paints are preferred. Unlike latex paint, the solvent paint stripper for this kind of paint is not of superior quality.
The acrylic is inert to the caustic based paint stripper so they must be rejected for this purpose. They commonly use solvent stripper are ammonia solutions, isopropyl, lacquer thinners, spirit, and acetone.
How to remove paint from concrete without chemicals?
There are different methods of removing paint without using chemicals, however, these processes are mechanical or physical processes that may require excessive amounts of energy and power.
Some common methods used are,
- Sand blasting or soda blasting
In this method, the propelling jet of sand or soda solution(sodium bicarbonate) is targeted to the surface of the concrete where paint has to be removed.
The sand or soda is propelled at extensive pressure along with help of a compressor and nozzle. And they are targeted to the concrete surface for abrasion of the paint. The fine dust of sand or jet of steam then removes the paint.
- Power washing
The jet of water is used at very high pressure to remove the paints. The concrete can withstand a tremendous amount of pressure so they prefer or removing paints in concrete. Mode over they cannot cause any effect to the tough concrete layer but are enough to remove the paint.
- Thermal process or heat gun
The mechanism is based on the process of applications of heat to remove the layer of paint. The heat of 500°C to 600°C is created to melt the paint.
Such heat guns produce a tremendous amount of toxic fume. But in the modern era, with the use of laser and infrared, the heat can be controlled to 200°C, and paint is easily removed without creating toxic fumes.
The steam is also used for a small piece of works. The heat gun is pointed out 5 inches far from the surface of the concrete.
I hope this article on “How to remove paint from concrete floor?” remains helpful for you.
Happy Learning – Civil Concept
Civil Engineer – Rajan Shrestha