How to plaster corners: detailed instructions

Gusevsky Andrey Anatolyevich

Plastering corners

Plastering corners is the most difficult. Especially when the angle is not straight and you cannot apply the pattern.

How to plaster corners in different versions, we will consider today. Also, in the video in this article, you can visually see all the work and after that do it correctly.

Rules for performing work on plastering corners

Plastering corners with your own hands is not so difficult, here you just need to be careful and not rush. After all, the angle must be deduced so that it has the correct geometric shape.

The price of such work is high if you invite the masters. How to plaster corners: the video will show how to do the work yourself.

Plane preparation

Plastering the corners with your own hands should begin precisely with the preparation of the base plane. After all, the fit of the material and its service life will depend on this. This work is done the same way, regardless, it is an internal or external corner.

Doing the preparation of corners

So:

• First of all, the previous coating is removed. If this is a finished corner.
• Now we need to check the deviations. This is done using a building square.
• If your angle is not right, then just look at its plumb line deviations. Or it is quite possible to apply a fishing line. We stretch it and see which layer should be applied.
• If the layer is more than 2 cm, then it is better to make an angle by mounting drywall. If less, then it is quite possible to plaster.

Caution: Before applying the material, a primer coat must be applied. Better to apply deep penetration.

Making the inner corners

Plastering surfaces having corners involves finishing two types of internal corners: finishing an internal corner adjacent to a facing surface, and finishing corners that are not adjacent to any other surface. In other words, we mean complete corners that need to be plastered on two surfaces.

Plaster corner internal

So:

• In the first case, when it is required to plaster only one surface of the internal corner, the solution is poured in the usual way. The solution is leveled using the rule in the direction from the corner to the wall.
• After leveling the solution, you can begin to form an angle. To do this, take a trowel or grater and put it to the inner corner at an angle of 30-40 degrees and begin to overwrite the angle with up and down movements.

Attention: In this case, the grater edge should be pressed to the facing surface, and the working part of the grater should be on the surface of the plaster.

• During movements, you should choose the optimal pressure on the grater so that the extra layer of plaster is removed, but it was impossible to remove all the plaster.
• When this layer has set, it is possible to produce a coating to complete the finish of the corner.
• Finish the corner with a foam or wooden grater, making circular movements. As a result of this work, the surface is smooth, without pits and tubercles.
• In conclusion, several broad up-and-down movements should be carried out for the final formation of the angle. In this case, the grater should be tightly pressed both by the working side to the surface to be treated and by the edge of the grater to the facing surface.

Exterior corners

Plastering the outer corners will be slightly different from the inner. You can also obtain smooth and high-quality outside corners in two ways.

We form the outer corner

So:

• One method involves forming an outer corner using a perforated metal corner. Using this profile allows you to get a high-quality and reliable angle with minimal movements.

Attention: The main thing with this method is to precisely install the metal profile and fix it securely. So that the profile does not get stuck during plastering, it needs to be given the opportunity to gain a foothold.

• You can fix it with a solution or gypsum putty. From how smoothly the metal corner is exposed, the outer corner as a result will be so even.

The second method involves forming an angle in two stages.

• First, one side of the corner is plastered, and after complete drying, they begin to plaster the other side.
• To facilitate the work, you can use a flat, wooden rail.
• To do this, first install the rail on one side of the corner, and then on the other. When installing the rail, it is advisable to use the building level.

Caution: On an obtuse angle, the plaster is applied in exactly the same way as on a sharp one. The most important thing is to monitor the correct formation from the very beginning.

We plaster slopes

After installing the doors and windows, slopes may appear that require plastering, and the plane of connection of the two surfaces forms an outer corner, which also needs to be formed.

Slope angle formation photo

So:

• During the plastering of slopes, it is necessary to ensure that the slope flow angles are the same, which is achieved by a uniform distribution of the plaster layers on the left, right and upper slopes.
• Evenly distributing the plaster on the surface of the slopes will help the template, which will help to form a flat and identical surface. The template can be made of wooden slats with a section of 20x40 mm. In terms of area, such a pattern should correspond to the area of ​​the slope. In fact, it is a rectangle bounded by the perimeter of slats.
• The use of the template is justified when the slopes are wide and there is a place for mounting the template. The template is attached to the slope in any way possible, but in order not to use fasteners, you can simply wedge it.
• After the inside of the template is plastered and slightly dried, it can be removed and plastered with the places that were freed up after removing the template.
• At the same time, the formation of the outer slope angle occurs.

Attention: It should be remembered that the external angles on the slopes do not have right angles, which imposes a certain complexity on the formation.

Unfortunately, it will be difficult to apply a metal corner, but with certain skills it is possible. Especially, this applies to places that are on the path of human movement: entrance doors (see. Front door trim: what options can be), balcony doors, etc. Here you can not do without metal corners.

Common mistakes when plastering corners

If plastering is carried out without a preliminary assessment of the condition of the working surface. As a result of such non-professional actions, cracks in the plaster may appear, and in some places its complete peeling.

• Plastering the surface without applying a primer can lead to roughness of the plastered surface. Such a surface can repeat the relief of the main surface.
• Application of a coating layer directly on a concrete base. As a rule, this leads to peeling of the plaster layer from concrete, since they do not combine with each other. In such cases, the work must begin with the finished gypsum plaster, which includes the necessary binding additives.
• Surface plastering is performed with long interruptions, which gives a less reliable surface. Slopes should be plastered in one go, for more uniform drying.
• The concrete base has a moisture content of more than 4%.In this case, the solution adheres very poorly to the concrete surface, because the surface does not absorb moisture. A solution from such a surface will simply float away.
• So that gaps do not appear at the joints of door frames and window frames with a layer of plaster in the future, expansion joints are formed in these places. Before applying plaster in these places expansion rails are attached.
• To prevent external corners from being damaged during operation, especially in places of heavy traffic, metal corners must be installed on them.
• As a result of cutting galvanized profiles, the grinder breaks the protective layer, which can lead to the appearance of rust at the installation sites of such profiles. To avoid this, profiles should be cut with metal scissors. This is the easiest and most reliable way.

Important Tips

For plastering, you can purchase the finished mixture or prepare the solution with your own hands. This applies to both cement and lime mortars.

• To prepare the solution, it is advisable to use drinking rather than industrial water.. In drinking water there is no such amount of impurities of various salts.
• To obtain a high-quality plaster mortar, it is advisable to use fine sand, since it will allow you to get a better surface layer.

Attention: It is not recommended to carry out plastering work at a temperature below + 5 ° С to + 10 ° С. At an ambient temperature of + 5 ° C to + 10 ° C, it is better to use Portland cement.

In this case, you need to remember:

• After pouring reinforced concrete structures, plastering corners is possible only after 28 days.
• Before applying a solution of any complexity, the surface should be primed (see Primer before puttying walls - is it needed) This applies to all types of surfaces.
• After applying the next layer, he needs to be given the opportunity to gain a foothold.
• If lighthouses (metal or wood) were used in the plastering process, they will have to be removed before applying the topcoat.
• If the surface is intended for laying ceramic tiles, then you can do without a covering layer.
• When using metal corners, it is not recommended to leave voids under them.
• For the formation of internal corners it is better to use a corner spatula. But it makes sense if there are right angles.
• After gypsum plaster, only after two weeks can you paint or paste wallpaper. If the plaster is cement or lime-cement, then this period is increased by 2 times.

Alternatively, you can recommend another technology for the formation of slopes. This technology consists in suturing slopes, both door and window, with drywall.

• The advantage of this method is that it is not necessary to wait for the slopes to dry. It takes minimal time to cultivate slopes using this method.
• In addition, a heater can be placed between the wall and drywall. Particularly relevant is the question of when to trim the upper slopes.
• As a rule, reinforced concrete lintels are located above windows and doors, for the sealing of which you need to have a complex solution and the presence of a reinforcing grille. The use of drywall allows you to simply solve this problem.

Plastering the corners with your own hands video will help you not to miss anything and make a quality corner.