The most common way to decorate the ceiling is by whitewashing or painting. And the most used for this paint - water-emulsion. Painting the ceiling with water-based paint at first glance seems a simple matter, but there are many subtleties, ignorance of which leads to the appearance of spots or stripes. How to avoid the appearance of such trouble we will tell further.
Preparation for painting
To self-paint the ceiling with water-based paint was qualitative and uniform, preliminary preparation of the ceiling is necessary. It is possible to achieve uniform coloring only on a flat, ground surface. Therefore, before starting the work, it is necessary to clean the ceiling of any previous coating (except for water emulsion, which is very well kept).
How to remove whitewash
If on the ceiling you have whitewash - chalk or lime - you need to moisten the ceiling with water, and remove the coating with a spatula. Peel all to concrete. You need to delete even the smallest fragments. Sometimes it is very inconvenient to scrape small areas with a spatula, it is easier to make it a wet rag.
In any case, after removing the whitewash, the ceiling must be rinsed with water and detergent. After complete drying - primed and puttyped with gypsum or cement (preferably white) putty until smooth, which is also called "under the egg."
How to remove old water-based emulsion
If the ceiling has already been painted with water emulsion, it will not be possible to remove it. The procedure depends on how the paint is kept on the ceiling. If it just changed the color and you need to update the ceiling, no blisters, cracks and other similar problems, you can get by with little blood. First - remove the dust (rag with water), dry, then primer. After drying the soil can be painted. But once again we pay attention - this procedure of action is applied only if the water-emulsion is kept well and there are no defects.
If there are cracks on the surface of the water-emulsion, swellings, it must be cleaned. Method two - dry and wet. Dry - this is scraped off with sandpaper (manually or with the use of the USM), wet - wash off. This method must be used for paint, which is not afraid of water. But it's very difficult to clean such a paint. If the water-based paint is kept well, no tricks help, but there are surface defects and need putty, take a sandpaper with a large grain and make the surface rough. After that you can putty. Further - on technology: we ground and after we are painted.
Wash off the painted water-emulsion ceiling twice abundantly by dousing hot water. The water should be almost boiling water - about 70 ° C. After wetting a part of the ceiling, wait 10 minutes, then once again moisten the same area with hot water. After about five minutes, you can remove the paint with a spatula.
You can repeat this procedure several times, gradually removing the lagging paint from the ceiling. Minor residues can be cleaned with sandpaper, and then rinse the ceiling, dry and primer. On the primer you can already putty, fry, smoothing down the shortcomings.
Types of water-based paint
Water emulsion paint is a water-based emulsion that contains undissolved polymer particles in water. Also, the composition includes pigments and various additives that change the characteristics of the final product. After the application of the paint, water evaporates actively and a thin polymer film remains on the surface.
Painting the ceiling with water-based paint begins with the choice of composition. They use four types of polymers:
- Acrylic. Aqueous emulsion based on acrylic resins allows to obtain an even surface, has good opacity, hides small surface defects, up to slots up to 1 mm wide. Its disadvantage is a high price, but it's easier to work with. In its pure form, acrylic compounds are hygroscopic and can only be used for dry rooms, but they do not interfere with the passage of steam. To create a waterproof film, add latex to the acrylic water-based emulsion. The same additive increases the elasticity of the dried film. Such formulations can be used in wet rooms.