The technology of painting walls from concrete will depend onfrom what is intended for the structure in which it is necessary to carry out painting works. To properly choose materials suitable for finishing concrete walls, you should determine their moisture content. 
Technology of painting walls. To do this, take a meter piece of polyethylene film and paste it with adhesive tape on the wall. A day later under polyethylene or condensation forms, which means that the wall is not ready for finishing works, or under the test piece it will be dry: this means that the performed work will be performed qualitatively. The main stages of painting concrete walls are cleaning and surface preparation, puttying, priming and painting.
Tools and materials
The concrete wall begins to be prepared for painting only after it has been checked for moisture. For work you will need: 
Rollers for painting walls.
- respirator;
- roller;
- rags;
- primer;
- brushes of different sizes;
- paint priming and for surface works;
- painting tape;
- sandpaper with different grains of grade 60-100;
- putty;
- spatula narrow and wide;
- clean capacity;
- a paint tray or a mesh;
- stairs;
- protective glasses;
- gloves.
A new roller before work should be lost inhands, rinse and make sure that his coat does not crumble. Brushes before painting also check for durability, so that the bristles from them during the work did not pour and did not remain on the wall for ever. It is best to do this in the store when buying. Back to contents</a>
Features of painting any concrete surface
Painting buildings under the open skyand intended for industrial work, requires pre-reinforcement of the concrete surface and cleaning it from dust and dirt. This will give a qualitative result. 
Scheme of painting the walls. All concrete walls are exposed to moisture. The use of impregnation significantly reduces its impact on the wall and protects the structure from premature failure. The use of a fluid solution is recommended during the preparatory phase for the painting of concrete products for internal and external use. This prevents the appearance of white spots on their surface. The applied paint and varnish coating is designed to protect concrete from the effects of external factors that destroy the structure. When working with any kind of paint before applying to concrete, it should be filtered and periodically mixed during painting. If you do not, the end result may not be what you expected. There are many industrial water-based paints for concrete, which can increase the humidity. This should be taken into account when the humidity is high. Painting should be carried out at a concrete surface temperature above 5 ° C. Optimal weather for outdoor work - cloudy, dry, with a weak wind. Do not recommend painting the surface of concrete if it is heated by sunlight. Unsuitable time for work - in the evening. Morning or evening dew, getting on a freshly painted surface, spoils all work. Back to contents</a>
We prepare walls for painting works
If you should wear a respirator and safety glasses,so as not to damage eyes and respiratory organs during repairs. Do not apply paint directly to concrete. The walls must be carefully prepared. If they have an old layer of paint, it must be removed. To do this, use a spatula or alkali. In the presence of dirt, soot, a solution of soda ash is prepared at the rate of 0.5 kg of active substance per bucket of water, with which contaminated places are treated. The resulting aqueous solution is used to wash the wall with a rag and then dry it. 
Scheme of painting a concrete wall with a roller. The preparation of concrete walls requires the removal of everything, which prevents the laying of the putty evenly. Small spots of rust can be removed by 15% solution of copper sulfate, treated with pre-clean water. If the rye has covered a large size, it is covered with rosin varnish. All cracks and chips on the surface are sealed with a repair mortar. After removing the remnants of paint and stains begin to remove roughness. To do this, use a large sandpaper, achieving the desired quality of concrete coating. The strength of the upper layer of concrete is imparted with the help of a flute. Its application will not let the wall fall apart and spoil its appearance. This is an aqueous solution of salts and acids, which are treated with walls. After cleaning the walls you need to wait until they have dried out. To accelerate this process in modern construction use thermal guns and electrical appliances that warm the air in the room and greatly reduce the humidity. Back to contents</a> The technique of plastering the walls is needed in two layers.The first coat is applied to remove any unevenness. The second layer gives the surface perfect smoothness, provided that the wall itself did not have major defects. When choosing a putty, take into account the total humidity of the place where the wall is located. For dry heated rooms, it is recommended to use dry mixes based on gypsum. At high humidity, dry mixtures based on cement are used. 
Scheme of putty walls. To properly prepare the solution for work, first read the instruction to use the purchased mixture, in which proportions should be indicated. Prepare the putty in a clean, deep bowl, adding a dry mixture to warm water. Stir it requires a special mixer, but you can use as an electric drill with a special nozzle, which can be bought at the construction store. The first stage of putty is called priming the surface. The work after its application is not continued until it dries completely. The time of this process is indicated on the package with the material. After the first layer dries, the surface is ground with 60-grade sandpaper. After the wall is brought into perfect shape, a second, finishing layer of putty is applied. After it dries, the surface is sanded again with 80 or 100 sandpaper. Back to the table of contents</a> Priming of concrete walls For concrete walls you needa special primer that can penetrate deeply into concrete layers. Primer the surface in several layers with a roller or brush to fully pass. 
Tools for plastering walls. It should be remembered that on painted walls of concrete in damp places salt deposits are growing. Crystals of mineral salts gradually grow and destroy layers of plaster and paint. In the street, it is necessary to protect concrete structures from direct contact with the ground. For this, reinforced primers are used. It can be Enesal SR or Enesal XP, which have an increased elasticity, three times the usual waterproofing materials. With them there is no peeling or bloating. This coating works fine if it is applied to a dry, firm foundation that is not subject to water pressure from the ground. For protection against water, the Enecritis BC system is recommended. It is a waterproofing material that prevents water from seeping from the negative and positive sides of the structure. All these are expensive types of insulation, which have shown themselves well in industrial facilities with high humidity. They keep the painted concrete walls from being destroyed. Back to contents</a>
The choice of paint and technology of painting walls from concrete
The choice of paint will depend entirely on themoisture content of the coating. In order to protect the walls from moisture, epoxy coatings are used. They have increased durability and are used in non-residential or well-ventilated rooms. Paints on acrylic-latex base have a low toxicity, and this allows them to be used in enclosed spaces. They well withstand temperature changes. 
Paint application scheme using a spray gun.When choosing paint for exterior walls or in damp rooms, look for those that contain antibacterial ingredients that prevent the growth of mold and fungus spores. To, you need to limit the working space using masking tape, which is pasted over the ceiling along the line of joining the walls with it. With the help of a damp cloth, remove from the work surface all construction dust that could settle on the walls prepared for work. Before work, the paint is mixed until a homogeneous mass is obtained and a small part of it is poured into a clean special container, from which it will be easy to apply it to a roller or brush. When working with a brush, make sure that the paint layer is uniform and that excess paint does not drip from it. For the roller, a special mesh or a bath for painting is used. These simple tools will help remove excess paint from the tool. The surface should be painted by evenly distributing the paint and rubbing it well. Usually, the main part of the wall is processed with a roller. For the brush, only those areas remain that are inaccessible to it. It is best to start the work from these inaccessible places. These include corners, places behind batteries, areas near electricity meters. To do it correctly, you need to use a special procedure for applying paint to the surface. They start work from the top of the wall, going down to the very bottom. At the same time, movements are made that create a W-shaped pattern. If the first layer of paint does not lay down very well, the primer is visible, then the second layer of paint is applied. The masking tape is removed after the paint is dry. If necessary, use a thin brush to tint places with gaps.
