Technology for repairing plaster of internal walls. If the plaster has come off the wall in places after repairs or is cracked, what could be the reason, and is it possible to eliminate the defect without new putty? How to cover up the plaster that has fallen off the wall?

The article describes the reasons for the formation of cracks in plaster on the wall, swelling of the surface, and its delamination. It also describes in detail how to repair a wall with cracks, and how to prevent a plastered wall from immediately cracking.

Causes of cracks

Blistering can occur due to incorrect composition of the solution. If unseasoned lime was used, in which there were unslaked particles, then after covering the walls, small swellings may appear on them. After some time, the coating will completely deteriorate. To prevent this from happening, you need to clean off the plaster with bubbles, and then spread a higher quality composition on the surface. Other reasons:

• Cracks may appear when using poorly mixed or greasy solutions. Fatty solutions are those in which there is an excess of astringents.
• Cracks also occur due to surfaces drying out too quickly. To prevent this from happening, you need to prepare the plaster strictly according to the instructions, carefully stirring the composition before applying it to the walls.
• It may come off the wall due to excessive moisture on the wall or an overly dry surface.
• It is also advised to wait until each applied layer dries, and apply the finishing coat to a completely dry wall.
• On a new wall in a built-in building, it is worth using concrete contact before each new layer of plaster, this will ensure adhesiveness, which is absent without preliminary surface treatment.
• You should not plaster walls in an unheated room before frost.

Why do walls crack after plastering?

If you cover a wall with a plaster composition without following the technology, it will definitely crack:

1. Aerated concrete is vapor permeable, which is why the plaster that is applied to aerated concrete must also be vapor permeable. It is even better if it has stronger vapor permeability than aerated concrete, otherwise steam will accumulate in the coating and it will crack.
2. You also need to remember that finishing must be done in one day. Otherwise, the next day there will be a different air temperature and humidity, they will change the conditions for the mixture to solidify, and the wall will crack.
3. If moisture gets on and under the plaster during work, it may crack.

What to do?

If the cement-based coating has come off from the aerated concrete, then it needs to be completely cleaned off and reapplied.

First, it is advised to finish the walls inside the room, and only then finish the facade.

The plaster may come off due to constant changes in humidity. You need to find the source of the increase or decrease in humidity and correct it.

If this happened due to a mixture of poor quality or an old composition, then you can only completely remove the old finish and apply a new one.

The problem should be carefully studied; perhaps this was due to subsidence, which appeared due to the fact that the plaster preparation time specified by the manufacturer was not followed. Then just redo everything.

When applying the mixture in hot weather, it is necessary to slow down the drying of the walls. To do this, they are moistened from time to time.

But if cracks do occur, then the walls are rubbed with mortar or gypsum dough. If the gaps are too large, they are widened, cleaned, moistened and plaster is applied.

Try placing paper tape over the peeling plaster area. If the tape breaks, you will have to start all over again.

Sealing cracks in plaster has its own algorithm of actions, filled with some subtleties that require careful study.

Subtleties of sealing cracks:

1. It is advised to buy a mixture of the same brand that was used previously.
2. You cannot work at air temperatures below +5°C and at humidity levels above 80%.

What to do if the wall cracks again?

• Cement must be carefully but thoroughly cleaned using a hammer and chisel. Any area that looks unsafe should be cleaned.
• Then thoroughly rinse the crack to remove any remaining material, dirt, or dust. Wait until everything is completely dry. At the same time, you can prepare the solution. Before application, the crack should be moistened from the inside and covered with a new solution.
• Next, attach the reinforced paper tape and wait and see what happens.
• Then you can plaster the tape. Afterwards it should be sanded and then finished.
• A crack that is less than 5 mm wide is covered with assembly adhesive before applying the finishing putty.

How to repair cracks in the wall if the cause has been eliminated, but many small cracks remain on the surface?

First you need to seal every crack, and then attach a reinforced mesh. Sealants can be used, but the sealant must have such properties that it can be applied to a lime wall.

If the wall is made of concrete, then initially you need to lubricate the crack inside with PVA glue, and then cover it with a cement mixture.

Why does plaster fall off the wall after renovation?

The plaster falls off the wall after repair due to non-compliance with plastering technology.

Make the mixture strictly according to the instructions, knead it correctly. If you did everything correctly, then you will need 9 kg of gypsum-based composition or 20 kg of sand-cement composition per 1 cm layer with an area of ​​1 m². It is required to stir the composition in clean buckets and use clean tools.

How to properly prepare a mixture of gypsum and cement?

1. If you are making a gypsum composition, then slowly pour the entire composition from the bag into cold water, wait a short time, and then mix again. Do not mix old and new formulations.
2. If you pour a lot of water into the sand-cement mixture, it will eventually shrink a lot, which will lead to cracks on the wall.

If the wall swells at the site of the crack

It may still peel off. This occurs because the solution was applied to an overly dry surface. Or this solution was applied to another solution having lower strength. To correct the situation, you should clean off the peeling plaster, wet the wall and apply plaster on it again.

Do not forget that before work you should carefully examine the wall and understand where else the material may peel off. When creating a solution and spreading it on the wall, do not forget that the strength of the solution should vary in decreasing order. That is, the first layer of plaster should be stronger than the rest.

Swelling also occurs due to plaster covering an excessively damp wall. To correct the situation, you should clean off the material, dry the surface and apply the solution again.

You need to follow these tips and recommendations when puttingtying walls:

1. Before applying the putty, you should wet the wall with plain water. This can be done with a spray bottle.
2. The temperature in the apartment should be less than +24°C, but more than +5°C.
3. It is impossible for direct rays of the sun to fall on the wall and for there to be a draft.
4. A solution with a layer of more than 2 cm must be secured using beacons.
5. Before applying the next layer, you should carefully inspect the previous layer to ensure there are no cracks on the wall.
6. Gypsum-based plaster is applied in a layer less than 1.5 cm, and cement-based plaster is applied in a layer less than 2 cm.
7. We must not forget that on surfaces made of brick, concrete, stone, plaster is applied in a layer of less than 0.5 cm, and on wood - less than 0.9 cm.
8. You need to read the instructions written on the bag of dry plaster.
9. The components should be mixed in a certain order.
10. The walls are reinforced.

To prevent cracks from appearing on the walls later, you must strictly follow the instructions. Avoid drafts and direct sunlight into the room.

If cracks do appear, they need to be cleaned and the walls puttyed again.

Useful video

Plaster is a universal coating for walls. It can be either an elegant and decorative part of the interior, or a regular plain background, or a rough option for preparing the surface for any finishing material. The plaster is quite resistant to moisture and can withstand various adverse effects, from temperature changes to scratches from animal claws. However, even this fairly durable material is prone to destruction. You will learn how to properly repair the plaster of internal walls in this article.

There are many reasons why plaster deteriorates and loses its aesthetic and functional properties. Most of them are easy to prevent during plastering work, but some cases cannot be foreseen.

Reasons that can be avoided:

• poor-quality preparation of the base for applying plaster;
• unremoved remains of the previous coating;
• incorrect selection of solution for the internal or external surface.

Reasons that cannot be influenced:

1. Cracks that appeared in places of increased load on the surface:

• window frames;
• doorways.

2. Defects in plaster due to long-term use.

3. Destruction of plaster due to natural disasters such as earthquakes.

Important! Plaster, like any other material, loses its properties over time, but any cracks and defects can be eliminated with your own hands. The price of plastering interior walls in this case will be significantly lower than when this work is performed by professional builders. Let us note one more fact that internal plastering of aerated concrete walls is as easy as finishing brick or monolithic concrete bases. Therefore, the main rule is to follow the sequence of actions and all the conditions of the damage repair technology.

How to check the strength of the coating?

Before starting to repair a visible area of ​​destruction, be sure to check the entire plastered surface. The check is done in order to prevent the rapid destruction of new areas. To do this, simply tap it with a rubber or wooden hammer.

Important! A durable coating produces a ringing sound, while a non-durable coating produces a dull tone.

Which solution to choose for repairing damage?

Repairs to plaster must be carried out with the same solution that was originally used to make the plaster.

Important! Don’t make the typical mistake of purchasing and producing what you think is a more durable composition, which is not always compatible with the previous coating. The price of plastering interior walls in this case completely depends only on the quality of the initial mixture for the mortar, so give preference to trusted manufacturers, but with an affordable cost of materials.

The texture, color and aesthetic appearance of the surface directly depends on what mixture you use.

Important! If the damage is significant and is caused precisely by the fact that the mortar was initially of poor quality, in this case it is advisable to completely replace the plaster rather than strengthen individual fragments of the wall with a different composition. Otherwise, repair work on plastering internal walls will have to be carried out regularly.

How to properly prepare walls when repairing plaster?

To save time and money, many people prefer to repair only noticeable irregularities and damage, not paying attention to the fact that in other places the plaster can also be kept on its word of honor. This looks presentable, but in practice it is fraught with constant re-restoration of the surface.

To avoid this result, before starting minor repairs, do the following:

Technology for repairing plaster of internal walls

Regardless of the type of material in need of repair, the operating technology is the same:

Video

Watch the proposed example of a video of plastering interior walls to clearly see the whole process and properly organize yourself when carrying out repair work.

Features of gypsum plaster repair

Repair of gypsum plaster is carried out in accordance with the basic rules for sealing cracks on the surface, but there are also some distinctive nuances. After checking the wall where cracks are found, proceed to repair the damage by familiarizing yourself with the suggested method below.

Tools

For DIY repairs you will need the following tools:

Surface preparation

This procedure is not much different from the standard preparation process:

Repair technology

Features of repair of cement-sand plaster

This type of plaster is no more complicated than gypsum plaster, the general algorithm for their implementation is very similar, but the method of applying the mixture and preparing the base also includes distinctive features.

Tools

For this type of wall repair, the following materials and tools are needed:

Technology

To obtain a high-quality coating of cement-sand mortar plaster, perform the work as follows:

Conclusion

When repairing stucco, it is important to be extremely careful and organized. Compliance with all rules will ensure high-quality and long service life of the new surface. If the surface of your home is significantly damaged, do not be lazy to completely replace the plaster, because it is better to do it well once than to redo the work in parts over and over again.

The beauty and neatness of any interior depends on many aspects, and walls play a big role in the design of the room. It is known that over time their appearance can suffer under the influence of various factors. In this article we will look at what to do if the plaster has come off the walls, as well as the reasons for this phenomenon.

All possible damage to plaster can be divided into 2 types: technological and operational. Below we will take a closer look at each of the categories.

Technological disadvantages

They can occur as a result of a violation of the technology for preparing the solution, as well as as a result of improper application of the coating to the wall. These defects include the following:

1. Bloating. One of the reasons that your plaster is falling off is the incorrect composition of the solution. If you use uncured lime, which contains unslaked particles, to prepare the mixture, it can cause small swollen tubercles to form on the walls. Over time, these voids lead to deterioration of the coating. In order to get rid of this problem, the area where bubbles form must be cleared of the plaster and a higher quality mixture must be reapplied.
2. Cracks. This phenomenon occurs when you use insufficiently mixed or greasy solutions. Fatty formulations are those that include a lot of astringents. The appearance of cracks is also promoted by drying the wall surface too quickly. To avoid the occurrence of such defects, you need to carefully monitor the ratio of all components in the prepared plaster, and in addition, mix the mass very thoroughly before using it. If you are treating walls in hot weather, you should prevent them from drying out too quickly. To do this, the surface must be moistened periodically. If cracks do appear, they can be eliminated by rubbing the wall with mortar or plaster paste. Very large gaps must be widened, cleaned, wetted and sealed with plaster.
3. It happens that the plaster comes away from the wall as a result of peeling. This problem can occur for two reasons: if the mortar is applied to a wall that is too dry or to another mortar that is less durable. To get rid of such a defect, the area with the peeling coating must be cleaned, thoroughly wetted and re-coated with the composition. Remember that before starting such work, you must carefully inspect the entire wall and determine in what other places the coating is peeling off. When preparing the mass and applying it to the wall, it is important to remember that the strength of the composition should change in decreasing order. That is, the first layer of solution should be stronger than the subsequent ones.
4. Swelling. Unlike peeling, this problem occurs due to the application of plaster to an overly wet surface. To eliminate this defect, the affected area will have to be cleaned, the wall dried and re-coated with mortar.

Operational defects

Another reason why plaster falls off is damage caused by aging of the coating. Such defects include the same cracks and peeling, only they do not appear immediately, but after a long time. To prevent the appearance of defects or eliminate them in time, you need to regularly inspect the coating and make repairs if necessary.

Plaster repair

So, your plaster has fallen off, what should you do in this case? The main way to combat this problem is to carry out repairs, which begin with removing the old coating layer. In order to carry out such work, you will have to acquire a suitable sharp tool that can be used to scrape off the old mortar from the walls. Remember that when clearing a specific area, you will also need to cover a small area around it. Let's look at the process of eliminating plaster defects in the form of a sequence of actions:

1. First, the damaged area must be cleaned of old plaster. This can be done by tapping, as a result of which the loose coating will simply fall off the wall.
2. From all the seams of the exposed masonry, you need to scrape out the mortar to a depth of at least 1.5 cm. After this, the treated area is swept from dust and moistened with water.
3. Then you should prepare a liquid cement mixture and cover the wall with it.
4. When the soil layer hardens, you need to make a lime mortar. If you want your wall to dry faster, add a little gypsum dough to the resulting composition in the following proportion: 1 part gypsum dough for 6 parts of solution.
5. Cover the surface to be treated with the resulting composition and rub in with a trowel. Treat the boundaries of the old and new coatings with adhesive paint and rub them in the same way.
6. All joints must be carefully smoothed - this way you will protect the wall from the appearance of depressions or bumps on it.
7. At the end of the work done, walk with a damp brush or sponge over the entire treated area.

Corner repairs are carried out as follows:

1. First, prepare the gypsum mixture.
2. Clean the corner of the old plaster, scrape out the seams and moisten the surface with water.
3. Then cover one side of the corner with fresh solution and wait until the composition hardens.
4. After this, a wet board is applied to the surface, which should lie flush with the old coating layer.
5. The next step is to moisten the second side of the corner and plaster it in the same way.
6. The boundaries between the old and new solutions are blurred.

Restoration of Venetian plaster

The process of repairing this type of coating will require a little more time and effort. This work consists of several stages:

1. First of all, the damaged layer of plaster is removed from the wall and the surface is cleaned.
2. After this, prepare a solution of PVA glue. Add 5 parts water to 1 part glue and mix the mixture thoroughly until smooth.
3. The wall to be treated is covered with the resulting mixture, covering areas around the damaged area.
4. Then apply a base layer of plaster and wait for it to dry.
5. After that, the surface area is covered with a finishing layer of plaster, which performs a decorative function.
6. The next step is to give the decorative coating the same texture as the rest of the wall. To do this, use sponges and special spatulas. The work should be carried out in such a way that no boundaries between the old and new cladding are visible.
7. After a few days, when the restored area is completely dry, it can be painted in the desired color.

Grinding plaster

In order for your plaster to last as long as possible without repair, it must be periodically updated. Over time, any plastered surface begins to become covered with small cracks. Before things go too far, you can grind the top layer of coating. This process is carried out as follows:

1. Old wallpaper is removed from the wall. If the paper adheres too firmly to the surface, it is soaked and scraped off with a suitable tool. Remains of paste or wallpaper glue are also washed off with warm water.
2. Do the same with paint, scraping it off the wall with a spatula. You need to work with the tool carefully, trying not to leave deep scratches on the coating, otherwise they will have to be covered with putty later. If the paint is water-soluble, you can simply wash it off.
3. The grinding process is carried out in zones. Select an area of ​​approximately 0.5 m² on the wall and moisten it a little.
4. Then, using a special trowel, the surface is covered with a thin layer of plaster. The distance between individual strokes should be about 10 cm.
5. After this, the treated area is thoroughly rubbed with circular movements of the tool.
6. If small defects remain on the wall, they are covered again with a small amount of solution.

Sealing cracks

If there are quite noticeable cracks on the surface of the wall, they are covered separately. To do this, the gaps are slightly deepened and the crumbling edges are cut off. After this, the defects are sealed with plaster. When it dries, the wall is rubbed down.

If cracks form at the joints of reinforced concrete floors, they are covered with a solution based on fine sand. After this, the surface is carefully leveled and rubbed.

The process of applying plaster to the wall can be seen in the following video:

All connections, including those used in furniture production, can be divided into two categories: detachable and permanent.

The latter constitute a special category, since special requirements are imposed on them. They work under conditions of temperature and humidity changes, which affects their durability and stability. And if detachable connections can be tightened or sorted out, then such a procedure cannot be carried out with permanent ones.

A little about the characteristics of D4 glue adhesives

In furniture production, adhesive permanent joints are mainly used. Since furniture is usually made from wood materials or derivatives of them, appropriate adhesives are used. One of the most important criteria characterizing glue is its water resistance. So, glue D4 It is considered the most water-resistant compared to the others. This is all the more important because polyvinyl acetate dispersions, widely used as furniture adhesives, work even in tropical climates.

About gluing

The drying parameters of the glue during application are affected by temperature, humidity and the pressing force of the elements being glued. Higher temperatures shorten the time required for compression, while humidity increases it.

Another point is the humidity of the surfaces being glued. For most moisture-resistant adhesives it should be between 7 and 10%. That is, the surfaces must be dry.

A little physics

The physics of the process is such that during the absorption of moisture, the adhesive layer swells, and during evaporation and recoil, on the contrary, it dries out and loses in size. Such fluctuations lead to the fact that the adhesive seam “dissipates” and loses strength and geometric stability. Essentially, these cyclic vibrations lead to the destruction of the joint and the furniture as a whole. This is why the moisture resistance of the glue is so important.

ABOUT THE PROCESS OF ADHESION USING D4 GLUE

When gluing, it is advisable to reduce the gap between the parts to a minimum, since a large tolerance and an increase in the glue layer reduce the strength of the seam and increase the drying time. Glue is applied to one of the surfaces and the surfaces are pressed against each other. It also doesn't hurt to clamp them with a clamp. The seam gains its final strength and water resistance after 7 days. As a rule, glue does not change the color of the wood, but contact with metal should be avoided, since, together with the tannic acids of the wood itself, it can change its color. The adhesive layer itself can also be painted.

Repairing plaster, applying plaster, sealing cracks in ceilings and walls, repairing and leveling external corners, lapping bevels.

First, we determine those places on the walls and ceiling where the plaster is already beginning to crumble or is simply cracked. Often old plaster falls off even when wallpaper or paint is removed, but it still doesn’t hurt to check the entire area covered.

It is most convenient to check for weakness of plaster with a scraper or spatula. First of all, we check the joints of concrete panels and ceiling slabs, as well as the corners of the room.

The test is carried out by tapping the coating with the above instrument. In those places where the plaster holds weakly, it will, if not crumble, then make a dull sound due to the fact that a void has formed under it. In these places you need to remove the old plaster, and if it is a crack, use a spatula to make a V-shaped depression. Detected and treated defects are covered up.

How to repair cracks in a ceiling

Before you start sealing cracks in the ceiling, it is necessary to thoroughly clean the area where the solution will be placed once again. Then this area should be moistened with water so that it is well saturated.

Repairing cracks in the ceiling produced in several stages and in small portions. At the first stage, the solution is placed at the very bottom of the V-shaped recess and spread over its entire area. Before applying the second portion of the solution, you must allow the first to dry until it hardens. The second portion of the solution must be applied so that it fills the crack by 2/3. The second portion is also spread over the entire area of ​​the recess.

After the second portion of the solution has hardened, you can begin the last stage of sealing the crack. This time the solution is applied and rubbed flush with the ceiling surface.

It may be difficult for a non-professional to immediately measure the required portion of the solution, and in this case we can recommend the following: measure the first portion with a regular tablespoon. To do this, the solution is scooped up with a spoon so that it forms a heap, and it is sharply splashed onto the desired place. After this, you can use a trowel or the same spoon to lay the solution more carefully and spread it over the entire area of ​​the recess.

To make the solution more flexible and hold stronger, you can add PVA glue to it in a ratio of 1:10. However, there is one point here - such a solution should be used as quickly as possible, since PVA glue increases the speed of its setting significantly.

PVA glue can also be used to prime the surface on which the plaster is applied. To do this, it should be diluted with water and applied with a brush, after which the first portion of plaster should be immediately applied.

Applying plaster to the ceiling

In the event that you are not repairing a crack, but a large part of the area ceiling, the solution should be applied in one layer. For this you will need a special formwork board, which should be slightly longer than the width of the surface being repaired. It is better to paint such a board so that the solution does not stick to it, or even better, lay a layer of plastic film between the board and the solution.

The solution is applied to such an area that the formwork board completely covers it, and is pressed with the board. To support the formwork board, two spacer boards are used, which should be slightly longer than the height of the room. Spacer boards are installed between the floor and the formwork board, supporting it on both sides.

How to repair cracks on walls

On the walls plaster repair you need to start from the bottom. First, the defects that are located at the bottom of the wall are plastered, and lastly, the junction of the wall and the ceiling.

Repairing cracks on walls is done in the same way as on the ceiling. You just have to take into account that the solution must be applied from bottom to top. This is done so that the solution does not come off as it is applied.

Repair of external corners

You should dwell in more detail on the repair of external corners. This is the most difficult task when repairing plaster on walls. The main thing here is proper preparation. Old plaster should be removed a little more than is required when repairing walls. In this case, it is necessary to make a ledge from below the processed surface of the corner in order to applied plaster It didn’t fall off right away and held on better later.

You need to make something like formwork. To do this, you can use a strip longer than the size of the defect. The batten is pressed vertically against the left side of the corner along the entire height of the defect and supported by one or two boards (from the floor to the batten).

The defect area must be moistened with water before applying plaster. The plaster is also applied from bottom to top in three stages between the lath and the corner. Each subsequent portion of the solution is applied only after the previous one has dried. The formwork can be removed only after the solution has completely dried.

Aligning outside corners

After the solution has completely dried, you can begin leveling the corner. Leveling is done using sandpaper, which can be wrapped around a wooden block for more convenient use. You can also level the corner using pumice.

Leveling (grinding) the outer corner after repairing the plaster is done like this: you need to stand opposite the corner so that both walls making up the corner are in the field of view. In this position, the result of the work will be clearly visible.

The most difficult thing when aligning the angle is chamfer grinding, that is, the direct junction of the walls. If the cut is uneven, the angle will appear uneven. Therefore, if you can’t smoothly grind the chamfer cut, it’s better to apply a new one to it. thin layer of plaster, and after drying, rub in until a good result is obtained.

You can level the outer corner with a special tool - a trowel for outer corners. This tool looks like a spatula, the working surface of which is bent at a right angle. However, in any case, an ideal result can only be achieved manual lapping.