How easy and simple it is to make even and straight corners with plaster. The curvature of the corners and walls is characteristic of the premises of houses and apartments, which were erected in Soviet times, but this fate has not bypassed new buildings either. Aligning the corners is a mandatory procedure, since otherwise the pattern on the wallpaper will inevitably be damaged, and for a ceramic tile you will need to use up a lot of glue, and then, a positive result will not be 100% guaranteed.
Let's look at how to make a right angle when plastering walls.
Uneven corners is not only not aesthetically pleasing, but also an obstacle for all furniture and household items you choose so carefully the technique fell into place, since any, even the slightest deviation will be visible to the naked eye.
In addition, family photos from a photo session, paintings or panels cannot be placed near the corner, since they will perfectly "emphasize" the errors of the wall joints.
There are two ways to solve the problem, and each of them has its own advantages and disadvantages:
Now let's go directly to the process, or rather to its subtleties.
Details and subtleties of the process
Leveling corners with plaster
Consider everything you need to know before starting works:
For finishing work, use a mixture made on a gypsum base. Such material is convenient to use in work, if you follow the technology, then it will show its strength and will serve for many years. The thickness of the mortar on the walls is about 5 cm, and for local recesses up to 7 cm. For the ceiling, the indicator does not exceed 3 cm at all.
- Plaster should be applied to concrete, brick, sand-cement, gypsum surface.
The mortar cannot be used for wood substrates, as the materials simply will not bond properly to each other (poor adhesion).
- The surface should be treated with various impregnations and other compounds in order to prevent the formation and development of mold and mildew. To improve adhesion, first prime the surface that contains the gypsum mortar.
- During the preparation of the mixture, the instructions indicated on the packaging by the manufacturer should be strictly followed. The ratio of powder to water is indicated on the package with the material.
It is important that all proportions are observed, and if there is little liquid, then add a little more, because otherwise the solution will be difficult to apply and there will be a high probability that everything will crack after drying. If you add a lot of water, then this will not allow filling the voids and gaining the required strength of the solution.
It is better not to use industrial water for the preparation of the solution, since it may contain various impurities, which sometimes negatively affect the quality of the solution. Since the mortar itself is thick, we recommend using a construction mixer, namely a nozzle that is inserted on a perforator / drill, and from time to time stir the solution for 2-4 minutes.
- It is not necessary to add special plasticizers and additives to the mixture, since all the necessary components are already in the finished dry composition.
- The ready-made solution should be worked out in half an hour, so mix everything in small quantities. If the solution dries up, do not try to refill it with water and stir it, as this will only worsen the overall quality of the mixture.
- Small indentations may sometimes appear on the surface. If you plan to glue ceramic tiles, then it is not necessary to close up the errors. For pasting or painting, the surface will have to be brought to perfect condition.
But before you start making even and straight corners with plaster, you should follow a series of preparatory steps.
The instructions for performing the preliminary work are as follows:
Clean the base from an old coating layer that does not adhere well. A rule should be applied horizontally and vertically to the corner, and the longer it is (100-200 cm), the more accurately it will be possible to fix the result. Bumps and bumps should be knocked down with a chisel, and what cannot be removed will serve as a specific starting point for performing leveling work.
- If there are any local depressions, then fill them with the mixture and wait until everything is dry (this will take at least 48 hours).
Next, plaster the entire surface. We do not recommend applying a thick layer of the mixture immediately, as this will not give positive results, it is better to do the work a little slower and in several stages, but the result will delight you for many years!
Tools and attachments
Angle and straight trowel.
- Long building level, plastering rule.
- Slicker, sandpaper.
- Gypsum mix, perforated corner (counter-shell).
When everything is ready, let's go directly to the process.
How to align the corners
It is possible to get rid of the curvature of the internal joints of the walls, if you use counter-shell and reinforcing mesh / construction beacons. The first method is perfect if you have a wall on which there are slight irregularities, and the installation of beacons will be relevant if the flaws are significant. Outside corners should be leveled using a countersunk or a lath that is ideal for smoothness and level.
Plastering inside corners
Plastering with beacons
The beacon method can be used if you plan to align the walls with the joint.
In this case, attach even wooden / metal slats to the surface with screws or dowels, it all depends on which of the materials for the frame you choose. The step between the guides should be the same as the length of the rule. Installation of the lighthouse in the corner should be done 6 cm from the junction of the walls.
- Use a plumb line to mark the ceiling and floor where the battens are located. When fixing, it is worth checking how accurate the installation is, both horizontally and vertically.
Use wedges if necessary.
- Apply the plaster mixture on one side. To do this, fill the opening with mortar between the beacons and distribute it evenly using the rule. After everything is dry, you can start performing work on the adjacent wall.
- When you try to make an even corner with plaster with your own hands, make sure that a lot of gypsum mixture does not accumulate in the corner, and if this happens, then after drying, remove the excess with a spatula as carefully as possible.
- To create a nice and even corner, use an angled trowel to make the job much easier. In the process, it is worth regularly moistening it in water. When you use a straight spatula, the movements must be abrupt, from the direction of the corner.
- When thorough drying has been performed, the beacons can be removed. The remaining recesses should be filled with the same mortar.
Now we will learn how to work with a profile corner.
Plaster with profile corners
- A method in which using a perforated corner and reinforced mesh around the edges, will be optimal if the walls have been pre-aligned. The contraschulz should be cut to the length of the joint, and for this we recommend using metal scissors.
- The aluminum product is soft enough that it does not require much cutting effort to keep the geometry set by the manufacturer. After that, apply some plaster mix with a flat trowel to the wall joint itself.
A piece of material should be applied to the corner and pressed down slightly using a long and perfectly straight rule.This should be done carefully, as the material can be easily deformed. Excess from the prepared mixture, which will begin to show through the holes, should be removed with a spatula (away from the corner to smooth the mesh).
- When the surface is dry, it should be plastered. Finish leveling if necessary and apply a thin layer of plaster mix.
For convenience, we suggest using an angled spatula.
There is one more, no less interesting way - with the use of serpyanka.
Plaster with serpyanka
This is the third option for machining an inner corner where a wide serpian is used. This method will be very relevant if you do not want to carry out large enough work on all surfaces, and you have only one task - to make a 90-degree corner joint.
- In this case, you will need a tape for reinforcement, a wooden beam, which has a right angle and a length from 0.
4 to 0.6 meters, as well as the gypsum mixture itself.
- Apply a small amount of the solution to the joint of the wall, grab 10 cm of area on adjacent surfaces.
- Attach the edge of the serpyanka to the very top of the corner, the tape should be held at a given point, the roll can be unrolled to the full width of the arms. It is important to provide for the position of the reinforcing material in the lower part of the corner, as it often happens that the serpentine is "off course".
- Use the bar pressure to shape the seam into a right angle. Next, take a spatula and align the jammed tape with it, and the excess mixture can be smoothed with movements from the corner and reduced to nothing. You can also use an angled spatula, which should be periodically moistened with water.
- Be very careful not to change the position of the wet tape. But at the same time, you should not wait until the putty dries up, since in this case it will no longer be possible to perform the adjustment.
This was the third and one best way to make an even inner corner of a wall with plaster.
Plastering external corners
External corners and slopes can be brought to the desired ideal in two ways - using a perforated aluminum profile and without it ...
Alignment without countersunk
With this method, it will be necessary to knock down the protrusions and fill in large gaps and other local recesses.
- On the adjacent side of the corner, place a flat plank / plank that will be wrapped in a layer of tape. It should be fixed to the floor and ceiling, and if the length is chosen correctly, it can be installed as a spacer.
- The overhang of the plank from the corner must be equal to the thickness of the plaster layer.
- Apply a layer of the mixture to the surface and spread using a rule. The movements must be circular, go to the corner with a slight downward slope.
- When everything is dry, you can repeat the previous step.
- Now it remains to wait at least 48 hours, and then you can carefully remove the board and apply it to the corner, which is plastered. Perform all manipulations in the same sequence.
- The finished 90 degree angle must be sanded with fine sandpaper.
- For sanding, 2 trowels can also be used, but dexterity and firmness of hands are required.
The second way is more interesting.
Corner for plastering using countersunk
The corner profile will be an excellent protection for slopes from mechanical damage , accidental chipping, will also be able to give strength and even create a flat surface vertically. It is not difficult to calculate the material - to do this, measure the length of all corners, and then add up the result. In the resulting figure, add another 15% for consumption.
- It would also be dishonest not to note that if, in addition to corners, you plan to level slopes, small niches or ledges, then you can save a lot on buying a counter-shell.
The fact is that manufacturers offer such a consumable in a standard length of 3 meters, and the height of the ceilings is usually no more than 2.7 meters, so there will be cuttings of 0.3-0. 5 meters, which is very cool and profitable.
- Lines are useful for creating corners in small areas.
It is not recommended to use fragments of a perforated corner if the length is longer, as this threatens the appearance of cracks.
- Apply the mixture to the work area (on both sides of the walls that are adjacent).
- Attach the corner of the selected length to the reverse zone and press down a little. To do this, it is better to use a rule that will not allow the corner to deform due to carelessness of pressing.
- Remove excess gypsum mortar that will bleed through the holes with a spatula.
- While the mortar is still fresh, check the position of the corner with a spirit level or laser. Make adjustments if required.
- When you achieve the desired result, remove excess filler from both the end and adjacent sides of the profile.
- After residual drying, remove any imperfections with fine-grained sandpaper.
- The final leveling of the surface is possible if the plaster mixture is applied to the main surfaces (ceiling or walls).
As you can see, making an even corner with your own hands is not difficult at all!
The best option
And the cheapest and a simple option for leveling external / internal corners, window / door openings would be to use a plaster mixture. Although the method itself is dusty, dirty and laborious, but for finishing an apartment, small in area, this is the very thing. The advantages include the fact that the method can be used on any surface except wood, the finished base is very durable, and there are also all the possibilities for creating an extraordinary coating.