Painting experts
When renovating old premises, the owner has a question about whether it is possible to paint with water-based paint over whitewash, what is needed for this, how to do the work correctly so that the old plaster does not fall off the walls and ceiling.
Experts advise to first get rid of the whitewash and then start painting, but you must take into account that when washing the plaster a lot of dust will accumulate, so you will need polyethylene to pre-cover the surfaces to be treated before work.
Features of water-based paint
Water-based paint is significantly different from other types. It dries much faster. The fastest drying paint takes only two hours. The water emulsion will not cause harm to health; it contains no toxic substances. You can work without a mask; there is no need to close the room until it dries completely. Due to the absence of harmful substances, the paint has no odor.
There is no need to ventilate the room after this.
- The choice of colors is unlimited. Using a color scheme, you can make the shade you want yourself. The paint is sold primarily in white form.
- The paint is easy to apply and anyone can do it themselves. The water emulsion will serve you for 15 years without shedding. At the same time, it is inexpensive.
- There are also disadvantages to water-based emulsion. The operating temperature should not be below 5 degrees. Painting is possible only in the warm season or in a heated room.
- The paint does not like direct mechanical influences; over time it will wear off and be washed off due to frequent cleaning. She doesn't really like water.
Do I need a primer?
If you want to get a strong and durable coating, you should not skip this step. Moreover, the primer is inexpensive. Its main purpose is to strengthen the base and improve the adhesion of paint to the wall. After treatment with a similar composition, a loose wall turns into a monolithic and durable coating.
The primer is able to fill the smallest pores, and the surface after its application looks smoother. The fact is that such compositions form a thin, durable film that prevents moisture from being absorbed from the paint. As a result, it lies flatter. Therefore, before applying water-based paint to lime, be sure to prime the surface.
Since it is sold in concentrated form, dilute it with water according to the instructions on the package. If the composition is too thick, streaks may form on the walls. It is better to add a little more liquid and treat the surface twice.
You can replace the primer with regular PVA glue. It is added to the water emulsion in a ratio of 1:10. The result is a waterproof composition, similar in properties to acrylic. A wall covered with this paint can even be washed.
Types of water-based paint
Water emulsion is divided into 4 types according to composition: acrylic, silicone, silicate, mineral. Some will cost more, others will cost less. Let's take a closer look at them.
Acrylic paint. It is used most often, but therefore it is not cheap. It has the highest quality set of characteristics. Suitable for painting inside and outside. Due to the acrylic content, the paint is waterproof.
It can be washed without risk of abrasion and used in rooms with high humidity. It is the easiest to apply; it does not absorb into the surface. If the paint contains latex, it can cover small cracks. Acrylic paint is not subject to fading: the sun is not afraid of it. At the same time, it is safe and does not emit unpleasant odors: you can paint a nursery or kitchen.
Silicone. The paint is suitable for rooms with high humidity. Better suited than acrylic. The structure of silicone is much more elastic than latex, which means that it can hide larger cracks. The paint allows steam to pass through, which will save you from the appearance of mold and mildew. There is no need to additionally impregnate with antifungal compounds. Good for the bath or kitchen. Repels dirt - you don't have to clean the surface often.
Silicate. Ideal for finishing the outside of a house. Not suitable for interior decoration. Can be used for outdoor work or in extensions without heating. Long service life and resistance to any weather conditions make it the best among paints for exterior decoration.
Useful tips
Without the proper experience and specialized education of a plasterer-painter, it is rarely possible to carry out the first painting efficiently. But a number of tips will help:
- If there are small defects on the surface, then it is better to use a matte water-based emulsion. Glossy painting will only emphasize unevenness and roughness.
- Wear protective equipment: glasses and a respirator.
- Select the composition of the water-based emulsion, taking into account the purpose of the surface to be painted:
- acrylic water-based paint is not afraid of either ultraviolet radiation or high humidity, a universal option for building facades and interior spaces;
- silicone water emulsion is an excellent option for the bathroom and kitchen, it has high vapor permeability;
- a cheap but not durable paint based on lime and cement, but is rarely used due to unreliability.
How to paint a ceiling with water-based paint over whitewash
It is still not recommended to apply paint to whitewash. It must first be removed. Painting over whitewash is possible only if it is in perfect condition: if it does not crumble or crack. Try running a clean roller over it. If the whitewash does not remain on the roller and does not begin to fall off, then you can paint directly on it.
If the whitewash is swollen or cracked, then you cannot apply paint to the whitewash. Otherwise, it will begin to crumble right in the process of work. The paint will lie unevenly, and your ceiling will be hopelessly damaged.
If you still plan to apply paint to the whitewash layer, then all you need to do is simply prime the surface of the ceiling. After this, try to disturb the surface again, and if there are no falls, then go to work.
Materials and tools
Whitewashing the ceiling is performed with the following tools:
- a roller is a simple, convenient tool, it is easy to process the surface without leaving streaks or streaks;
- with a brush - when used, visible strokes and stains remain on the base, so the tool is used in hard-to-reach areas where it is inconvenient to use a roller;
- with a spray gun - allows you to evenly distribute the composition, speeds up the work, does not allow the emulsion to drain, however, the smallest particles of the mixture can get into the eyes or onto neighboring surfaces.
To prepare the surface for painting and conveniently apply the composition you will also need:
- sandpaper;
- masking tape;
- polyethylene film;
- putty knife;
- emulsion tray;
- ladder.
Ceiling preparation
The first thing you need to do when working with paint is to remove all the furniture. Of course, you can cover it with film, but there is no guarantee that there are no holes in it or that it will not tear. It's better to endure everything. When working, use gloves and a mask. Lime is not good for health.
Whitewash is easier to remove when wet. Use warm soapy water. Apply it around the entire perimeter of the ceiling. Change the water when it gets dirty. Treat the entire ceiling thoroughly.
If you have a thin layer of whitewash, then when soaked, you can remove it with a regular roller. Also moisten it periodically with water. Instead of a roller, you can use a brush. For ease of work, you can use a spray bottle and wet the ceiling with it, and remove the coating with a sponge.
If the whitewash is not removed in this way, you will have to work with a spatula. Use it to scrape off the whitewash from the ceiling.
Another way to remove it is with a paste. It simply sticks to the whitewash and, after drying, turns into a film that is easier to peel off. You can make the paste yourself. Add flour or starch to boiled water. Stir gradually to prevent the formation of lumps. Cool the mixture slightly and apply it to the ceiling with a roller or brush, spreading evenly. Then wait until the mixture dries and forms a crust. Remove it with a spatula.
If this does not help, the whitewash can only be removed with a sanding machine. There will be enough drinking, so close the door and put on a protective suit. Then you will need to thoroughly clean the entire room. Preferably several times with special means.
And the most radical way of getting rid of it is removal with acid. You need to work with full protection: glasses, mask, gloves and suit. Add acetic acid in small portions to water. There should be no more than 3% acid per volume of water. The order is exactly this: water, then small portions of acid, otherwise it will react. Apply the solution to the ceiling with a brush and then remove the coating with a spatula or brush. The ceiling surface must be washed with soapy water.
After removing the whitewash, fill all cracks and holes. Prime the surface. Choose a primer specifically for the paint that you will be applying. Preferably from the same manufacturer.
Recommendations from experts
- It is better to take paint from the middle price segment and refuse cheap, low-quality materials.
- Do not buy it at the market, but go to a hardware store where storage rules are followed.
- To avoid purchasing counterfeits, study reviews of manufacturers online, and check quality certificates in the store.
- Paint the ceiling with a long-pile roller - it gives a more even layer.
- Do not apply water-based emulsion in a thick layer. Distribute the composition evenly, if necessary, re-treat, waiting until the first layer has completely dried.
- If the emulsion was applied unevenly, after drying, you can correct the unevenness with sandpaper.
It turns out that making a ceiling in a room yourself is not difficult. To do this, you will need minimal knowledge about the most common methods and some free time. Read about how to install suspended, slatted, wooden, textured, plasterboard and fabric ceilings in our materials.
Painting the ceiling
Before application, you need to add color. The main difficulty is to dilute at once as much as is needed for coating, otherwise it will be very difficult to get exactly the same color.
Pour some paint into a measuring container. Inject the color through the syringe. It is important to use measuring containers, since these measurements will guide you when adding color to the main container. Remember your results and calculate how much color you need for the volume of your paint bucket. After you have mixed them, try spreading a little on a small area and see if it is the color you want.
The instructions for the paint describe in detail how and in what quantities to dilute it. The paint is mixed before application and water is added. The composition is mixed and poured into the paint bath. Periodically dip the brush into the bath and wipe off any excess. So paint the entire ceiling. If your finish has absorbed a lot of paint, apply a second coat.
