When decorating kitchens and bathrooms in Soviet times, they often resorted to painting walls. Today, such methods have gone down in history, but their consequences are still confusing for many apartment owners who want to make modern repairs. Is it possible and how to remove old paint from a concrete wall?
- Difficult dilemma
- Which way to choose
- Methods for removing oil paint
- Mechanical method
- How to work with an ax
- Work grinder
- Using a drill
- Chemical method
- Thermal method
- Free from water-based coating
- How to remove acrylic coating
Difficult dilemma
Starting repairs in housing, which was built more than 30 years ago, many are wondering: is it necessary to remove the old paintwork from the concrete wall? The answer to it depends on what kind of finishing work will be performed.
For example, if it is decided to cover the surface with drywall, removing the paint is not necessary. Whereas the application of tile adhesives, building mixtures, cement-based plasters with paint is incompatible due to the low, almost zero adhesion (adhesion) of the painted surface.
to contents ↑Which way to choose
When deciding how to remove paint, four key points should be considered:
- surface view and planned work;
- type of paint, degree of adhesion;
- available tools;
- budget.
There are several types of paint:
- oil;
- water emulsion;
- acrylic.
It is most difficult to remove traces of oil paint from a concrete surface, especially if the base has not been previously plastered.
As for tools, in order to remove the old paintwork, you will need:
- a grinder equipped with the right nozzle;
- water;
- chemical compositions (washing off);
- building heater (hair dryer);
- small tools, convenient for bringing down paint;
- ax;
- rotary hammer / electric drill plus specialized nozzle.
Methods for removing oil paint
Removing old paint from the wall occurs in three ways:
- chemical;
- mechanical;
- thermal.
Mechanical method
The first thing everyone is starting to do is who faced the need to remove the old paintwork. The positives are non-toxic. Disadvantages - a lot of dirt and dust. Given the minuses, in addition to the above tools, a respirator and goggles must be in place to avoid particles of coating in the eyes and respiratory tract.
What does the mechanical method imply? This is cleaning the surface of a concrete wall with a grinder, complemented by a wide nozzle, a chisel with a hammer (can be replaced with an ax), as well as an electric drill.
It should be noted that an ax was used long before the invention of power tools as an instrument for combating old oil paint.
Dust from working with him is much less, the risk of injury is minimal. In addition, you will have to make a little effort.
to contents ↑How to work with an ax
The essence of the work is a chopping subject. With the help of an ax, the sharp part located at a slight angle relative to the wall, shallow cuts are made on the surface. They should be short, but in large numbers. The main goal is to achieve a feeling of roughness. The next step is spraying the surface with water. The fluids should be allowed to soak, and then with the help of an ax, remove the paintwork.For greater efficiency, you should choose the optimal angle of inclination of the ax blade.
You can also clean mechanically the surface of a room with a hammer and a chisel. The principle of operation is similar to that used for the ax. It should be remembered that from frequent strokes the chisel may become dull.
to contents ↑Work grinder
During work using a grinder, a lot of dust is generated. As a rule, after a one-minute treatment, you have to wait about 20 minutes for the dust to settle. That is why this tool is used extremely rarely.
Using a drill
To remove paint using a drill, you should purchase one of three nozzles:
- Paint remover (represents a design of three chains with 13 links in each). Positive aspects of work: the paint is removed in small pieces, without the formation of dust, the layer of plaster (if any) remains intact. A relative disadvantage is that the chain is destroyed during paint removal. It must be replaced as soon as three links remain on each side.
- Brush It creates a lot of dust, although the application efficiency is quite high.
- Crown nozzle. The best choice for concrete walls. Does not form a large amount of dust. Cleaning will take a lot of time and effort, but the result is quite high.
Chemical method
Flushing can be of two types:
- alkaline;
- organic.
Theoretically, the technology of work is as follows: the wash is applied to the surface for 10 minutes, then this action should be repeated several times. The paintwork should begin to move away from the surface, after which it can be removed with a sharp spatula.
Features:
- The “older” the paint, the worse chemicals will handle it. The maximum age allowed is two years.
- Chemical vapors are dangerous. Therefore, during work should use protective equipment: glasses, gloves, respirators. From the premises you need to remove animals and other residents, especially children.
- It is better to carry out work in the warm season to ensure long-term ventilation in order to remove the unpleasant odor of the wash.
Thermal method
It implies the use of a special building hair dryer. The method does not always seem appropriate. Concrete cannot be heated to the temperature at which the paint begins to peel off.
Only wooden surfaces can be cleaned with it. When a jet of hot air hits the paint, it begins to become covered with bubbles, after which it is easily removed with a spatula.
It should be remembered that the thermal method is not suitable for areas where wires, sockets are located. In addition, a hair dryer is useless for a concrete wall.
The main disadvantage of heating is the release of odor (unpleasant and very corrosive), as well as toxic substances. Therefore, the room should be thoroughly ventilated. A respirator is also required.
The heated coating should be removed quickly, otherwise the paint will bake and it will not be possible to clean it.
to contents ↑Free from water-based coating
Many are convinced that to remove water-emulsion paint and varnish from the surface, it is enough to moisten the wall with water and wait about 10-20 minutes. And indeed it is. But you will have to moisten quite abundantly. In addition, the procedure must be repeated if several layers of paint were applied to the wall.
There is one exception to the above rule: if the surface has been additionally treated with a protective agent, cleaning it with water alone will not work. Special compositions will help to cope with this.
It is also possible to clean the water-based coating by heating with a building hairdryer. Softened by hot air, the coating is removed from the surface. If the area is large enough, the procedure will take a lot of time and effort.
You can apply the mechanical method - a puncher, a grinder. However, in this case, it is easy to damage the plaster. Removing the incisions and roughnesses takes a lot of time and does not always give positive results. This can be avoided by using special chemical compounds that disrupt the adhesion of coatings and make it loose.
to contents ↑How to remove acrylic coating
Acrylic paintwork, as a rule, is chosen for painting wooden substrates. But there are special compounds that can be used on concrete surfaces.
The method of cleaning the layer is chosen based on the age of the stain (if known). For example, fresh ("age" no more than a few hours) easy to remove acrylic paint ordinary warm water. If a day has passed since the application of the material, you should arm yourself with a brush and any degreasing agent. An “age” coating with a highly hardened film-forming material is cleaned with white spirit, acetone, gasoline or a wash. The liquid is applied with a sponge. It will take about half an hour for the layer to soften. After that, wipe the surface with a soft cloth dipped in the already used composition.
Thanks to the knowledge on how to wash off unnecessary paint, it is possible to update the wall covering without any problems and make the interior more attractive.
