Before finishing the ceiling, first of all, remove the old coating. This process takes a lot of time and effort, so the question is quite natural - how to paint the ceiling with water-based paint after whitewashing. It turns out that this option is possible, but only in some cases.
Whitewash painting: when you can and when you can't
According to unspoken rules, water-based paint should be applied to a thoroughly cleaned and then primed wall or ceiling. This contributes to optimal adhesion and further strength of the coating, its operational stability and durability. Applying paint to a poor-quality base will lead to flaking of the material.
The seemingly even and thick chalk or lime coating seems to be very reliable, but when applied to it with water-based paint, it can swell, crumble and fall off in pieces. Even if the layer is medium or thin, but it is stained with dirt, soot or grease stains, these defects can be noticeable after a couple of coats of paint. In this case, some areas will have a different color from the general background, so in both cases it is not worthwhile to paint with whitewash, wasting effort and money.
The exception is a thin whitewash applied to the surface once, clean and not crumbling. If, at the same time, after priming a small area it does not get dusty, this is exactly the case when it makes sense to paint over an already treated base.
Water-based paint: the nuances of use
The choice of the coloring composition directly depends on the purpose of the room, which requires staining, after all, there are several types of this material.
Acrylic water emulsion can be used for interior and facade finishing works. It is not afraid of abrasion, ultraviolet radiation and high humidity, therefore it is often used for painting any premises. Since the composition is considered safe and does not emit toxins, it can be painted with it in a kitchen, living room or even a children's room
- If acrylic material is made containing natural latex, then it can partially hide minor surface imperfections.
- Silicone based paint is more plastic than acrylic and latex, which allows you to close cracks up to 2 mm in size, moreover, it has a high vapor permeability. The latter determines its purpose - it is ideal for bathrooms and kitchens. Dirt-repellent properties will save the hostess from regular cleaning of the surface, in addition, such a water-based paint eliminates the appearance of mold and other microbes.
- The most inexpensive mineral paint type based on slaked lime and cement although it is suitable for any grounds, it is rarely used, since it does not differ in durability.
- Water Based Silicate Materials mainly used for outdoor use. Therefore, for whitewashing staining, you will have to choose from two options - acrylic or silicone mixture.
In general, water-based dyes have good performance characteristics, they are easy to apply, dry quickly, and any desired coating color can be created by tinting. But it should be remembered that work should be carried out at a temperature not lower than 5 degrees Celsius. Also, this material should not be washed too often, moreover, it is susceptible to mechanical damage.
How to clean the base from low-quality whitewash?
You should always be prepared for the fact that the previous coating still has to be removed. A layer of lime, so strong and even at first glance, can present an unpleasant surprise, and then the owners will be forced to re-repair the ceiling or walls. Sometimes this happens after the paint has been applied.
Whitewashing is required in most cases, so you should know how to do it efficiently and without a lot of time. It all depends on the thickness of the old layer and its strength:
- if the thickness is insignificant, then the sander for walls and ceilings will quickly cope with cleaning, and at the same time give the surface smoothness;
- the average size of the layer is easier to separate from the walls by picking it up with a roller with a hard nap or with a poppy brush, having previously moistened them in water or using a spray bottle;
- thick layers of the old whitewash are removed with a scraper or spatula, after wetting the coating and letting it swell, you can add vinegar or citric acid to the water.
After cleaning, the surface is examined for grease, rust and dirt.
Traces of rust are washed off with an emulsion of copper sulfate, fat - with linen (soda ash). If soot is present, it can be cleaned with hydrochloric acid. You can also wash off the previous coating with water with soap and ordinary soda rubbed into it, special washes or paste, which, in addition to the old layer, removes dirt and dust.
Only chalky whitewash can be effectively washed off with water. For lime, it is better to use spatulas and spatulas. The grinder is used for different types of whitewashing, but has one significant drawback - it leaves a lot of dust, which is why you still have to wash the base.
To process the ceiling, you need to prepare all the necessary tools in advance. To complete the task you will need:
- container for the coloring composition;
- regular paintbrush and narrow brush;
- putty knife;
- primer and fur roller;
- sticky masking tape;
- abrasive sandpaper for grouting;
- water emulsion;
- coloring pigments, if a certain color tone is assumed.
In addition, for safety reasons, you will need special protective clothing, a mask or respirator, gloves, and goggles to protect the eyes. Despite the fact that there are no toxins in the emulsion and it does not have an annoying odor, the material remains a chemical composition and, if small particles get on the skin or in the upper respiratory tract, it can cause allergies, irritation and other health problems. It is rather difficult to wash it off the skin, but for this you can use diluted vinegar essence.
An important point is the preparation of the room - it is desirable that the furniture is not present in it, but you can simply close it from contamination with a polymer film.
To dilute the solution, a plastic container, gloves, water and color are taken. Effective mixing will be provided by a construction mixer. The required amount of can paint is poured into the bath. Water is added little by little while stirring with a mixer until the desired viscosity is reached.
Pigments for tinting are placed in a shallow bowl, where a small amount of paint is poured. Continuing stirring, they begin to combine the mass with the main composition until they achieve the desired shade. Too thick, viscous solution is also diluted with clean drinking water.
Even in the case of a perfectly flat and durable whitewash, experienced builders advise to prime the ceiling surface and only then apply a water-based composition. How the coating will lay and how strong and smooth it will be depends on this important action.
In the process of painting, you should adhere to some recommendations
Painting is carried out using a roller or spray gun by spraying. With a paintbrush and a narrow brush, complex areas, joints and corners are painted, as well as the necessary correction. If a roller is used, it must necessarily have a long pile
- When painting, good lighting is desirable to avoid the appearance of streaks on the surface from hand tools. Processing always begins with the corner zones and joints connecting the walls and the ceiling, in a living room this is the central (far) corner from the entrance opening.
- The water-based paint is applied with a roller back and forth so that it is evenly distributed, therefore thorough rolling is important. Previously, the excess of the coloring mass is removed from the roller with a ribbed surface.
An electric spray gun will help in uniform staining of ceilings. In addition to the fact that it significantly reduces the labor intensity of the process for large areas and saves processing time, it can be used to achieve a minimum layer thickness, and therefore faster drying. Spray painting does not leave streaks, streaks and streaks that occur when working with a brush and roller. For ceiling-mounted applications, you only need an extension cord for the sprayer.
You can also use the manual option for water-based paints, which is more affordable and easy to use. The device uses a lower pressure than electric models, but you can get out of the situation by choosing higher quality paints and adjusting the consistency of the solution.
If another coat is applied over the water-based paint, the maximum surface strength will be achieved.
It turns out that water-based dyes themselves can serve as a primer. Such materials are the fastest drying, the maximum drying time for most species is two hours. This is the advantage of paintwork data, but it also presents some complexity in the process of work, because the correction of streaks and other defects must be done quickly.
Unfortunately, it is impossible to calculate the result of such staining completely - unforeseen situations also happen. If there are small defects or irregularities on the whitewashed substrate, they can be difficult to detect, but when covered with paint, they can become obvious and spoil the appearance. When the ceiling has been covered with lime and chalk several times, the material may become viscous and sticky during painting, and this will lead to adhesion of small particles to the roller, which will complicate the work process.
Therefore, to work on top of an existing layer of whitewash, it is better to choose a matte water-based emulsion composition, which, unlike glossy, masks flaws and roughness. For finishing on top of lime and chalk, this is the best option, as enamel and oil-based paints should not be placed on these materials.
You will learn more about the technology of painting the ceiling with water-based paint in the following video.