Aligning the ceiling with plaster – how to do it correctly

A flawlessly smooth ceiling can significantly enhance any room’s appearance and atmosphere. But getting that perfect surface frequently takes some effort, particularly if the ceiling is uneven or has flaws. Plastering the ceiling to align it is one of the best ways to handle this challenge.

Although plastering may seem like a difficult undertaking, anyone with a little perseverance and the appropriate tools and techniques can complete the project. Not only will knowing the procedures help you complete the task professionally, but it will also save you time and effort.

From surface preparation to smooth, even plaster application, this tutorial will take you through every step of plastering a ceiling. These tips will assist you in completing the task correctly, regardless of your level of experience with do-it-yourself projects.

Plastering a smooth, even ceiling involves a methodical process, the appropriate tools, and meticulous preparation. You can steer clear of typical pitfalls and produce a finish that looks professional by using the right techniques. This guide will help you ensure that your ceiling is perfectly aligned and ready for painting or other finishes, regardless of the size of the imperfections or unevenness.

Preparatory work

For illustration, let’s consider the option with the most complicated initial data: you need to replaster an old, uneven concrete ceiling that has cracks along the joint between the floor slabs and an existing coating.

Removing the old coating

Let’s get straight to the point: if you don’t want plaster to fall on your head someday, any outdated coatings must be removed. This is a very messy and unpleasant, but essential, renovation step.

The type of finish determines the removal method.

• Chalk or lime whitewash, gypsum putty is soaked in warm water to soften, using a roller or brush. Then scrape off with an old but sharp spatula while the coating is wet;

Advice: It’s easier to just wash off thin layers of whitewash by repeatedly changing the water.

• Water-based paint is soaked in water with the addition of iodine (10-liter bottle);
• Water-insoluble oil paints and enamels will have to be scraped off "dry" with a spatula and a metal brush. The task will be greatly facilitated by a drill with a wire attachment or a professional remover – a special agent that destroys the coating. It is applied to the surface with a roller and removed with a spatula after half an hour. The price of such products is not always humane, but it will take much less time and effort.
• If the ceiling was plastered, it must be carefully tapped with a hammer to identify peeling areas – they must be removed. For this, it is often necessary to use an axe, chisel or hammer drill, but the coating that is weakly attached to the ceiling and the area of ​​10-20 cm around the unreliable area must be knocked down.

The ceiling needs to be cleaned once the work is done because dust, grime, and paint residue are still there after the old coating has been completely removed.

Verify that the ceiling is free of mold or mildew, which is another crucial detail. The presence of brown-green and black spots suggests that the room’s ventilation system is malfunctioning because of excessive humidity or that it doesn’t warm up properly in the winter. Frequent leaks from the roof, neighbors, or above could be another cause.

This is of great importance! Fighting fungus won’t help if these causes aren’t taken care of. It will reappear and spread, which poses a risk to one’s health in addition to aesthetic issues.

Mold removal involves first mechanically cleaning the affected areas, then using a gas burner to burn the mold and apply specialized antifungal agents to the large margin surrounding the affected areas.

Sealing joints and large defects

Before beginning work, watch the plaster ceiling leveling video. You can ensure that the process requires more time to prepare for, but don’t skip any steps as the quality of the finish is dependent on both your safety and the ceiling’s appearance.

Therefore, the first step is to prime and thoroughly clean the spaces between the floor slabs. Apply the same technique to areas with fallen old plaster and deep potholes.

Repair plaster is applied after the primer has dried:

• Potholes and chips on the surface are sealed with quick-hardening cement putty, filling them up to the ceiling plane;
• Joints and large cracks are blown with polyurethane foam and after it dries, the excess is cut off. Or they are caulked with tow soaked in liquid gypsum putty. Then a layer of putty is applied to them, a strip of plaster fiberglass mesh is glued to it, which is pressed into the solution with a spatula. The width of the strip should be greater than the width of the gap. Excess putty squeezed out through the cells is rubbed onto the ceiling with a spatula.

Following that, they wait for the repaired areas to dry before giving them a light sanding and carefully priming the entire ceiling plane.

Ceiling plastering technology

Plaster on beacons can be used to level ceilings just like it can walls (see Installing beacons for plaster – all the nuances and secrets). However, this is rarely actually required because nobody will be checking to see if it is perpendicular to the walls, nor will there be any furniture positioned on it. Therefore, without bringing the plane to an ideal horizon, it is sufficient to just make the surface smooth and even.

There’s still another explanation. A thick layer of plaster applied to the ceiling is not permitted by the instructions because it could fall off under its own weight and injure the room’s interior and its occupants.

Consequently, it will be more prudent and less expensive to construct a suspended ceiling out of plasterboard when there are discrepancies greater than 50 mm and you want to attain perfect alignment (see Ceiling plasterboard: doing it right).

Choosing a plaster

The thickness of the planned plaster coat determines the material selection. You will need coarse-grained plaster for thick layers even if you have refused to level and the ceiling slabs are laid with a significant difference (up to 50 mm), requiring alignment.

Use putty with smaller grain size if the difference is small (up to 20 mm) and all that’s needed is basic leveling and removal of small flaws on the plane.

Kindly take note. Plaster ceilings with your hands and gypsum-based compounds for optimal results. They have good adhesion, are lighter than cement, and do not crack after drying.

These mixes are made as a dry powder that needs to be combined with water to create a workable solution. The manufacturer labels the packaging with the component proportions and order of action.

A large container (plastic bucket), a drill with a mixer attachment, and the following details are required for mixing.

• Gypsum compositions set quickly, so the amount of mixed solution should be such that you have time to use it up within half an hour;
• The container, tools and water must be clean, the inventory must be washed after each mixing;
• The warmer the water, the faster the finished mixture will harden. It is best to take water at room temperature;
• After the final mixing, do not add water or dry mixture to the solution.

Work procedure

After making the solution, you must get to work right away so that you can apply it to the surface in 25 to 30 minutes. You can learn more about plaster ceiling leveling from the video than from any written description, but there are a few points that are worth emphasizing.

• Coarse-grained plaster is applied in a layer of at least 5 mm, and for putty this thickness is the maximum. If necessary, you can make several layers for final leveling, but each previous one must dry well.
• The solution is applied to a wide spatula and transferred to the ceiling with a movement towards you, after which it is leveled.

• After applying plaster to an area of ​​1.5-2 sq.m. it can be leveled with a rule, holding it with a beveled edge towards you. The thickness of the layer will depend on the angle of the rule to the plane: the steeper it is, the thinner the layer. You should try to keep this angle constant.

• On the knocks of walls and ceilings, as well as in hard-to-reach places, irregularities are smoothed out with a spatula.
• If a second layer of plaster needs to be applied for alignment, then the first, while it is not dry, is processed with a plaster comb or a notched trowel to obtain relief. Or the first layer after drying is impregnated with a primer.

Kindly take note. The environment’s humidity and temperature affect how long the layer takes to dry. With the use of heaters and draft-producing devices, it is impossible to artificially alter them; otherwise, the plaster within will remain damp while the outer layer dries and solidifies.

After drying, the final layer of plaster is sanded using a float equipped with a sandpaper or plaster mesh nozzle. For the purpose of later pasting wallpaper or ceiling tiles, such treatment is more than adequate (refer to Facing the ceiling with tiles: selection and characteristics).

It needs to be puttied with finishing putty before painting. Sheetrock polymer putty or Vetonit on a gypsum base work well for this application.

Plaster ceiling alignment may seem difficult, but with the appropriate method and equipment, you can complete the work independently. Plaster is applied in layers and requires preparation before you can achieve a smooth, even finish that improves the overall appearance of your space.

During this process, patience is essential. Any uneven surfaces or cracks that result from rushing through the steps will take more time and effort to fix. Long-term trouble can be avoided by taking the time to do things correctly the first time.

When finished, a well-plastered ceiling improves the appearance and resale value of your house. It offers a polished, orderly appearance that can be the ideal foundation for any additional painting or decorating.

Video on the topic

Alignment of the difference in ceiling slabs

Gypsum plastering of the ceiling without beacons. PLATÓ Start. Hand-held monolithic pouring.

Alignment of the ceiling

Give up on ALIGNMENT!!! A pitfall in plastering work. Advice from the KARKASNIK channel.