How to properly plaster a gas silicate house outside. How to plaster aerated concrete walls - requirements, nuances, secrets. Plaster with cement-sand mortar

Aerated concrete has long been loved by private developers for its excellent performance and very attractive cost. However, before starting construction from it, you need to study all the "pitfalls" in this matter in order to build a high-quality and durable structure. So, when planning the finishing, it is important to know how to plaster aerated concrete inside the house, and what materials are prohibited. What are the reasons for such restrictions and what kind of finish is ideal for gas silicate blocks, we will consider below.

Features of finishing aerated concrete walls

Before plunging headlong into the issue of finishing the walls, you first need to understand the structure of the gas blocks, from which the quality of the future home will completely depend.

The main method of obtaining this cellular material is the introduction of special additives into the composition of the concrete solution, which, upon reacting, form air bubbles that tend to escape. They simply sprinkle the aerated concrete body not only with voids, but also with thin channels, forming a surface that resembles natural pumice in its texture. Such a structure has excellent positive properties with the correct final processing of blocks:

• high sound absorption coefficient;
• good level of thermal insulation;
• "Breathing" walls create a unique microclimate in the room, keeping warm in winter and cool even in the most intense heat;
• the porous structure of aerated concrete is not susceptible to the emergence and maintenance of colonies of fungal and other microorganisms, which, as a result of their vital activity, destroy the walls.

But despite these wonderful performance characteristics, aerated concrete also has disadvantages due to its structure:

• the porous structure is subject to increased water absorption, which is fraught with rapid destruction of blocks;
• products with the highest density index, and, accordingly, strength, do not differ in resistance to mechanical stress, leading to spalling and cracking;
• an inhomogeneous structure that retains heat so well is very sensitive to wind. Unprotected bare aerated concrete walls are strongly blown through, and it is cold inside them, even despite a well-organized heating system.

Taking into account all these negative circumstances, we can come to the conclusion that aerated concrete walls need mandatory finishing. But it must be done as competently as possible so as not to disrupt the microcirculation inside the walls, which can lead to destructive processes.

Vapor permeability

The porous structure, about which so much has been said, has another property - good vapor permeability, which is the key to the durability of any aerated concrete structure.

In the process of life, people release a large amount of all kinds of moisture into the atmosphere. Just imagine how it saturates the air when ironing, washing, drying clothes, cooking or taking a bath. Of course, some of the generated vapors are removed using artificial and natural ventilation, but the bulk falls on the walls. In its pure form without finishing, aerated concrete perfectly passes moisture without retaining it inside its body.

It is another matter if there is a facade and internal cladding, and it is mandatory for such a wall material. Therefore, both finishes should complement each other, maximizing the natural removal of moisture.

For example, a ventilated façade system was chosen as an exterior finish. In this case, the provided ventilation gap does not disturb the natural moisture balance in the aerated concrete wall, leaving complete freedom for vapors to escape. In such circumstances, you can use any plaster for aerated concrete.

In the case of wall insulation, you need to pay attention to the characteristics of the base material. For example, mineral wool fully complies with the requirements - it insulates with high quality and does not interfere with the removal of moisture. As in the previous example, steam circulation is not disturbed, and the wall remains dry, so you can choose any plaster mixture.

How to maintain a natural moisture balance

But often, for one reason or another, facade decoration is arranged bypassing the basic rules, or, even worse, insulation was carried out with foam sheets (its vapor transmission capacity is practically zero) without a ventilation gap. This leads to the accumulation of moisture in the thickness of the wall, which over time manifests itself in damp corners, the collection of condensate in the room - and these are the first harbingers of the appearance of fungal mold.

Such a serious defect can be corrected only by using materials for interior decoration, whose ability to pass vapors is much lower than that of aerated concrete. This shielding method will prevent moisture build-up inside the walls. Best to use:

• paints with a special composition;
• waterproof wallpaper;
• cement-sandy plaster mortars of dense consistency.

But in this case, the importance of a high-quality ventilation device is significantly increased so that the accumulated moisture does not settle on the walls and inside the room, forming a greenhouse effect.

In order not to complicate the construction process, it will be most correct to initially produce interior decoration. After all, the repair involves a large volume of evaporated moisture, which simply needs to go outside, and it is best if he does it through the "bare" gas silicate walls.

And one more little nuance regarding the timing of the processing of walls from aerated concrete blocks. Any cellular materials give good shrinkage, which, in turn, negatively affects any finishing cladding - this usually manifests itself in cracking and peeling of the decorative layer.

Therefore, it is recommended to carry out both internal and facade finishing processes at least six months after the complete construction of the building box and the roof device. It is best to plan this phase of construction during the spring and summer period. As mentioned above - first, the interior decoration is carried out, after the end of all processes, in a month you can start processing the facade.

What plaster to prefer for interior decoration

As noted above, aerated concrete blocks are characterized by a high degree of water absorption, which can lead to excessive drying of the applied plaster layer. This is especially evident on gypsum compositions and cement-based mortars - fast drying, cracking and crumbling. If we go from the opposite direction, and excessively saturate the wall with water, then it will simply be impossible to plaster it, since the applied layer will not be retained on the aerated concrete base.

Choosing the right materials will help solve this problem:

• deep penetration primers with a special composition. Applying them, the main thing is not to overdo it and not to oversaturate the surface of the wall with moisture. Therefore, before use, read the instructions and follow them strictly;
• special mixtures intended for plastering of gas silicate blocks. Their composition perfectly protects such "capricious" porous surfaces. But this is provided that the plaster is diluted in the correct proportions with water. Only following the instructions for use from the manufacturer will help not to make a mistake in this matter.

But that's not all. The cellular surface does not have good adhesion properties. For this reason, it is necessary to initially apply a rough layer of plaster with a thickness of at least 5 mm. But even this finish is prone to cracking and flaking. To prevent this, a plaster mesh is used. Fiberglass or polyurethane is the best choice due to its excellent alkaline resistance and long service life. Only after the application of such a reinforced plaster layer and its complete drying, you can safely proceed to the final finish.

The best plaster mixes

Having figured out a little about what parameters the finishing mixture should meet, let's consider the most popular and effective types of it:

• plasters based on silicates, namely "liquid glass". They are perfectly combined with aerated concrete surface, especially in terms of vapor permeability. But there is a small "but". Such plaster mixes are incompatible with many types of final finishes, for example, based on acrylic, latex, silicone;
• gypsum plasters with perlite sand. They are ideal for aerated concrete wall surfaces, as indicated on the packaging. Any material for finishing is suitable for them;
• cement-lime-based plaster mixes with the addition of optimizing additives. Such compositions were invented specifically for finishing cellular material, even without a preliminary primer. Internal plaster of walls made of aerated concrete of such a plan has not only excellent adhesion properties, but is also applicable for both rough and finishing.

The use of such plastering compounds is ideal for gas silicate walls and, if desired, with their help, you can apply the leveling layer yourself. Like all specialized materials that have been improved for a single application, these mixes have a very high cost, which adds up to a decent amount in the end.

But there is an alternative that will economically resolve the issue of internal plastering - the use of a conventional cement-sand mortar in a ratio of 1: 5. But to use it in relation to aerated concrete surfaces must be extremely careful and not overdo it with the addition of water to the working mixture.

Self-plastering process

Even if you decide that the plastering of aerated concrete walls inside the premises will be done by masters, then it will not hurt to know the process of its implementation. After all, even professionals can sometimes make mistakes, and external control will help to avoid annoying shortcomings.

Preparation for plastering

The process algorithm for preparing walls for plastering is quite simple in execution, in which it is impossible to make a mistake. Therefore, you can do it yourself. This will require:

• or plastic 100-120 cm wide;
• adhesive for ceramic tiles;
• deep penetration soil;
• notched trowel with 5-6 mm notches.

Step 1. Carefully inspect the walls for building "jambs". For example, cracks and chips are subject to putty and alignment to the general level of the walls. For these purposes, an ordinary repair solution is suitable, however, if not much of it is required, then it is best to use glue specially designed for aerated concrete.

Step 2. After the restored parts have dried, brush all walls with a stiff brush to remove dirt and dust.

Step 3. Apply the primer in one coat. This can be done in a convenient way for you, for example, with a roller or brush. Experienced builders will use conventional sprayers to reduce the consumption of the primer solution. If these are not at hand, then you can just as well use an old model of a vacuum cleaner, the principle of which is to blow out air. Only after high-quality drying of the first layer can you start applying the second.

Stage 4. When the primer is completely dry, you can safely dilute the glue according to the instructions and cut the plaster mesh into strips, the length of which should be equal to the height of the walls.

Step 5. Starting from the bottom, throw the prepared glue onto the wall, gradually moving upward. The thickness should be approximately equal to a layer of 5 mm, and the width should be slightly larger than the width of the mesh.

Step 6. Apply a strip of plasterboard and press down until it adheres securely to the wall. Now you can level the adhesive layer with a notched trowel so that the direction of the grooves is horizontal. This improves adhesion to both the wall and future plaster.

Plastering

After the reinforced layer is completely dry, you can safely proceed to the main plastering process.

Stage 1. Wielding a building level, profiles - beacons are exposed.

Stage 2. The working solution is mixed according to the instructions. If the choice fell on a traditional cement-sand composition, then it is taken in a ratio of 1: 5, a plasticizer is added and kneaded to a thick consistency.

Stage 3. Between two beacons, a solution is thrown over the entire height of the wall. The rule aligns the resulting layer to the required smoothness level. Once again, attach the rule to the wall and check if there are any gaps between them. If there is, add mortar and level it, no - great, plaster all the walls in a similar way.

The described plaster technology is quite simple and even an inexperienced master can use it with success. The main thing is to choose the right way to plaster the walls of aerated concrete inside the house.

After the house is built from aerated concrete, the question of wall treatment arises. The first step is to tackle the inner walls. The peculiarity of aerated concrete is that it easily allows air and moisture to pass through, and therefore the insulating coating must first be applied to the inner wall. Thus, moisture will be forced out of the house.

Today we will find out how the internal plaster of aerated concrete is made. What materials should be used, and how the walls are processed.

Features of aerated concrete when plastering

In order to correctly perform all work with plaster, you need to know and take into account all the features of materials and construction. Different types of aerated concrete can have different properties. If you have to work with sawn blocks, then it will be easier for you to process the gas block, since it will have a pronounced cellular structure.

If a formed block was used for construction, then it will be more difficult to process it, since it has a hydrophobic coating. To plaster it, additional sanding and priming will be required.

In addition to the features of the surface of the gas block, you must also remember about the properties of vapor permeability. You need to start plastering from the inside. In this case, the thickness of the outer layer should be half the inner one.

Separately, it should be noted that the plastering of aerated concrete walls should be carried out no earlier than six months after construction. Such a period is needed so that the gas block is completely ventilated and gets rid of the moisture it contains.

Before starting work, it is necessary to clean the wall from dust and dirt. So that the aerated concrete does not strongly absorb moisture, and also accepts plaster well, it is necessary to treat the walls with a primer. Plastering should be carried out at temperatures from +5 to + 20 ° C.

How can you plaster aerated concrete indoors?

When choosing an internal plaster, you can ignore the moisture resistance properties, since all the moisture will be forced out. Due to the fact that we do not need such quality, internal compositions are much cheaper than external ones. You can save a lot on this.

Moisture-resistant plaster for interior treatment should be chosen only for the bathroom.

Most often, cement and gypsum plaster mixtures are used for interior decoration.

The first type is distinguished by a high level of vapor permeability, since their main component is lime. Cement mixtures have little elasticity and water resistance, but these disadvantages can be eliminated with the help of special additives. Modern fillers have a wide variety of properties.

Changing the color scheme is also possible with the use of special additives.

Gypsum compositions are used exclusively for internal plastering. Gypsum gives the material great lightness, as well as quick hardening. Due to these properties, the plaster sets quickly. It should be noted and adhesive properties, due to which the plaster fits well on the porous surface of the gas block.

Internal plastering stages

To give the plaster a special decorative look, you can use different color markers, as well as perlite or marble chips.

Calculation of the required material

Different brands of mixtures have different consumption. As a rule, the manufacturer indicates on the packaging the average value of the consumption of his mixture. When working independently, you can build on average values ​​at the level of 9 kg / sq. m. Thus, before work, you need to calculate the area of ​​the wall that you are going to plaster, and then calculate the amount of mixture that you need.

Required tools

There are a number of necessary tools that you cannot do without when plastering walls. These include:

• Master OK;
• long rule;
• spatulas of different sizes;
• grater;
• level;
• cord.

Preparing the walls

As we said above, before applying the plaster, you need to carry out preparatory work. Walls must be completely free of dust and dirt. In addition, it is necessary to prepare the surfaces themselves. This will require priming the walls. The primer is applied in 2 layers. After applying the first layer, let the second dry for 1-2 hours.

You can choose a primer specifically for gypsum plaster. Such formulations may be more expensive, but they will have the best properties.

Plastering

The plaster is applied in two passes. First, the first layer, 4 - 8 mm thick. Then a reinforcing mesh is laid on it. Then a second layer is applied on top. When applying, pay attention to the uniformity of the layer. There should not be any slopes or large joints on the wall.

After the plaster is completely dry, you can start decorative processing of the walls. It can be wallpaper, or a third layer of decorative plaster.

Conclusion

Internal plastering of aerated concrete should be done first. The layer of plaster should be double that of the outside. Thus, you can increase the insulating properties of the gas block, as well as its moisture resistance. In most cases, a plaster mix is ​​preferred. It is easier to lay down and has a number of advantages over cement mortar.

Plaster of aerated concrete walls

Renovation inside or outside the premises will not do without plastering walls and other surfaces. At the design stage of work you need to familiarize yourself with the features of the plaster, which are divided into types, they differ in characteristics and price. The correctly chosen type of finishing material is half the battle, because characteristics of mixtures can differ significantly among themselves, and what is ideal for one type of room may be completely unacceptable for another.

Some features of plaster

Plaster is a mixture that is used for surface treatment as a rough finish. What are the functions of the material? Plaster can be used to level walls, repair cracks and other defects. Itself the structure of this solution is a coarse mixture, therefore, after drying, the surface will have rough surface... These effects can be easily eliminated in the future.

Walls can be plastered of almost any type, concrete and wooden structures will be protected from the harmful effects of environmental factors. Various techniques and materials are used for plastering aerated concrete walls. Trends in the field of construction are developing in such a way that such building material as aerated concrete is gaining more and more popularity. It has many advantages over concrete and brick construction.

How to plaster aerated concrete walls?

One of the ways to decorate aerated concrete walls is plastering... For plastering walls made of cement-sand type blocks, this is the best option. As for the process of applying the finishing layer itself, if you wish, you can apply it directly to the wall. The same can be done with brick walls. However, this may pose some difficulties.

The brick is small, therefore seams between bricks serve as a connecting element when applying plaster. In the case of aerated concrete, the situation is somewhat different, because aerated concrete itself is large. This problem can be solved in several ways. Let's consider the main ones that are often used in practice.

With a hacksaw, you can manually apply grooves to the surface of the material... In the future, they will perform the function of a reinforcing mesh, which will ensure an increased degree of adhesion of aerated concrete and plaster.

Preparatory work

Before applying a layer of plaster, the walls are prepared from aerated concrete, this is necessary in order to ensure adhesion of materials. How is this done and what does this stage of surface finishing include?

First, you need pay attention to the seams between aerated concrete, they need to be well sealed, approximately by 4 - 5 mm... The wall is leveled, and all defects that may occur, dust and other microelements that reduce the quality of adhesion of materials are cleaned out. Sandpaper can be used to clean the surface to help sand the blocks more thoroughly.

How to apply mesh correctly when plastering walls?

If you decide to use the third method of surface finishing, then you need to know what is used in this galvanized mesh... It is more durable, reliable and does not rust. As for the size of the grid cells, you should pay attention to the one in which the cells are small. After carrying out the preparatory work, it will be necessary to attach the mesh directly to the wall. This must be done using ordinary nails. They are hammered into the wall first by one third, after which the nail is bent, fixes the mesh.

When the mesh is secured it is necessary to start applying the first layer of plaster. This is done in what is known as "Splash", it is mainly used to fill mesh cells with a solution. After it, several more layers of plaster will follow. This will necessarily be a primer layer, which must be kneaded by adding slag sand to the solution. The final layer will be the final layer; fine sand must be used to prepare the solution for it.

All layers of plaster can be apply with incomplete drying of the previous layer... This will shorten the time without compromising the strength and quality of the finishing layer.

Mortar for plastering walls can be purchased ready-made, it is sold in a dry state. To prepare the mixture, you just need to add water. But, you can also prepare a cement-sand mortar yourself. In this case do not skimp on the quality of the cement itself, since the water-repellency of the plaster will suffer as a result. When plastering walls, a lot of tasks and requirements are solved, such as thermal insulation characteristics of the surface, water resistance, noise insulation, and so on.

The sequence of work when finishing aerated concrete wall with plaster

The technology of plastering walls from aerated concrete is simple. Internal plastering of aerated concrete walls can be made with a cement-sand mixture or gypsum mortar. For interior wall decoration, it is recommended to use plaster based on gypsum and perlite sand. Each layer must be treated with grout, this is done half an hour after applying the next layer of plaster. The grout is dipped in warm water and then circular movements are made with the hand over the surface. Grout will make the surface smoother... The algorithm of actions will allow you to understand what is being done and why.

A layer of primer is applied, which will increase the adhesion characteristics and protect the wall from the harmful effects of moisture. A special type of primer is needed, which contains acrylatesiloxane in its composition. The optimum room temperature is 15 degrees Celsius.

With the help of a putty mixture, you need to attach a special type of mesh... It is alkali-resistant, does not dissolve during operation, which has a positive effect on the quality of the plaster layer.

After applying the finishing layer of plaster, the walls of aerated concrete blocks can be painted if desired. Moreover, you can paint both on ordinary plaster and decorative. Plaster called "bark beetle" is often used for wall decoration, it will give the surface an unusual appearance.

Choice of plaster

When choosing a method of surface finishing, you need to make sure that all materials are of high quality, used for their intended purpose and on time. The result is a surface that is durable and free from defects. If the question arises, what kind of plaster is better to plaster the walls of aerated concrete, then check out the assortment and choose the best option for yourself.

There is a huge assortment of plaster to choose from for interior or exterior wall decoration.... They can be applied in various ways, the simplest machine, the most popular is the manual method. There is also a huge selection among decorative plasters - these are Venetian and relief types, Danish, Byzantine, American, Munich, Moroccan and so on. It is also worth noting the fact that for walls that are subject to special loads, special types of plaster are provided. They are of different types and differ in such characteristics as frost resistance, fire resistance, heat resistance, moisture resistance, sound insulation, and so on.

Wall decoration with plaster must be produced with quality materials, which are selected on the basis of these characteristics of the parameters of the environment among and others. Aerated concrete walls are decorated with cement-sand type plaster or gypsum-based.

Aerated block wall: indoor plaster will keep the facade without cracks

The gas block is used in low-rise construction. The wall from it has 2 times less specific gravity than from silicate brick. This speeds up construction and reduces labor intensity. The properties of the material require that the plastering of the aerated block inside the room is made before the facade.

Features of plaster on the gas block

Before plastering the gas block indoors, you need to pay attention to some of the technological features of the process. Blocks made of aerated concrete have the qualities of lightweight concrete. This construction material has the following properties:

1. Increased vapor permeability due to the content of aluminum powder and cellular (open) structure.
2. Less cement, much more lime and quartz sand than aerated concrete.
3. The production uses water.

The fact that the product contains 30% moisture determines the sequence of wall finishing. The exterior decoration is started only after the plastering of the gas blocks inside the room is carried out. This is because outdoor work requires 15% moisture. Priority internal work allows moisture to evaporate from the outer surface of the blocks.

Special attention should be paid to this factor. A common mistake of builders is to plaster the facade in the first place, and the interior decoration - in the second (in winter). This approach is unacceptable: moisture escapes through walls and ventilation. When the outside temperature is below 0 degrees C, the steam turns into condensation and settles on the inner walls, as well as on the seams between the blocks and the outside finish. This entails cracking of the plaster layer. It flakes off.

The most reliable way is to start with the internal plaster of the walls from the aerated block.

Than aerated concrete is plastered

Experienced builders have long noted the advantages of buildings erected from aerated blocks. It differs from other types of materials:

1. The ability to breathe.
2. High strength.
3. The ability to retain heat well.

Experts know that easy penetration of moisture determines the choice and decides the question of what is the best way to plaster the gas block inside the house. A properly selected mixture allows:

• Achieve a moisture resistant surface.
• Eliminate shrinkage.
• Make the building aesthetic and original.

Based on these tasks, a plaster mixture with a high level of water permeability is selected. The composition of the finishing material must be adapted to work with cellular structures:

1. Hold a high concentration of adhesion (more than 0.5 MPa).
2. High elasticity.
3. Have enhanced vapor permeability.
4. Use no more than 0.2 liters of water when mixing 1 kg of the mixture.
5. Resistant to cracking.

These characteristics will help when choosing a plaster. If two mixtures have equivalent characteristics, then the prices should be compared. The long pot life of the grout simplifies the work. It is usually indicated on the packaging.

It is important to use special mixtures designed specifically for working with aerated concrete to obtain a high-quality surface.

How to plaster aerated blocks correctly when facing the outer surface? For this, a ready-made mixture for facades is used. It must have high resistance to sudden changes in temperature and atmospheric phenomena, and help preserve the appearance of the building. Meet the indicators of vapor permeability and hydrophobicity. Have increased durability.

Preparing the walls

To prepare the walls, work is used in several stages:

Cleaning from glue, cleaning chips, getting rid of sagging. All gaps are filled with the mortar that was used when laying the blocks.

The surface is leveled using a special float or planer. Usually performed during the construction of a building.

After applying the preparatory patches, the surface is swept with a stiff brush.

An important step is wall reinforcement using mesh.

Is it possible to plaster the gas block without carrying out preparatory work or skip any stage? If you need to save time, then many tend to abandon the alignment of the walls. It is believed that this point can be omitted. However, this approach requires a thicker layer of plaster and, accordingly, a higher consumption of the mixture. Possible peeling of the plaster, the appearance of cracks.

When all the preparatory steps are completed, they begin to apply the primer. This takes into account the use of materials with vapor-permeable properties. Drying time for the applied primer is no more than 3 hours.

Materials (edit)

Interior decoration serves for a long time if high-quality materials are selected, both for building and for plastering. There are no trifles in finishing work. For good fixing of the plaster on the surface, the quality of aerated concrete and mixtures is of equal importance.

When plastering a gas block, the functional use of the room is taken into account. For living rooms, light gypsum mixtures with perlite sand, chalk, limestone, marble, dolomite, etc. are used. In the instructions for use there is a mandatory note that the composition is suitable for application on aerated concrete walls. They have the following advantages:

1. High level of adhesion.
2. Fast drying.
3. The application of an additional smooth layer is not applied.
4. Plaster is easily leveled for finishing.

Do the fractions of the components affect the quality of the solution? In the production of mixtures, compositions are created with small fractions, which are most convenient to use - they are well rubbed, have a high whiteness indicator.

In rooms with high humidity (bathrooms, toilets), cement-based plaster is used, but without additives from gypsum, perlite sand, etc. The composition may include a complex of several types of cement. The mixtures take into account moisture resistance, vapor permeability parameters. With their help, moisture is prevented from entering the aerated concrete surface.

For the quality, durability of aerated concrete house plaster, it is best to take care of purchasing special mixtures on the market, in a store. A wide selection is offered by KNAUF. Mix-finish, Rotband, Fugenfüller received good recommendations from specialists. Noteworthy is the plaster with gypsum D.Mix hand plaster made in Turkey. There is a demand for putties under the brand name Ceresit CT 24 - Vetonit, Shitrok, which are developed for finishing aerated concrete.

How to plaster aerated block walls with a thick layer? To do this, you need beacons from a galvanized profile. It is necessary to choose a reinforcing mesh (mesh 5 × 5 mm). The quantity is determined by the footage of the surface. The type of plaster mesh is selected depending on the material of manufacture. Fiberglass varieties are recommended.

It is impossible to simultaneously carry out the interior decoration with a vapor-permeable material, and the outer one - with a vapor-tight material.

Instruments

Inside, a house made of aerated concrete is plastered using ordinary tools:

Capacity for solution preparation (tank, bucket).

Construction mixer, drill with attachment for mixing dry mixture with water.

Bucket, trowel for pouring the mixture.

Grater - used when rubbing the surface.

Poluter - used to remove excess solution.

Beacons - serve to level the side surface.

Rule - helps the contraction of the solution between the guides.

Long strip - to check the quality of plastering.

Applies to the wall horizontally and vertically. Shows the presence of defects. The error tolerance is no more than 6-7mm.

Putty

The house built of aerated concrete is plastered inside. Thanks to this type of work, potholes and all existing defects are eliminated. Plaster creates a base for subsequent finishing. It can be leveled only when it has not had time to harden. After that, they begin to create the upper, decorative layer - putty. It is leveled after it has dried using special graters.

When finishing the surface, it is used:

Classic - after laying the plaster reinforced with a reinforced mesh, putty is applied.

The classic method is recognized as reliable, durable. The surface is durable, smooth. There is one more - a simplified way. When laying the gas block, a flat surface with subtle joints is formed. They are easily overwritten. This eliminates the need for plastering. Working with putty consists in kneading and applying:

You can putty in 2 layers, if there is such a need or plastering has not been carried out.

Plastering of aerated concrete walls indoors

All the subtleties of plastering work must be known both to professional builders and developers who will accept the work performed. Aerated concrete walls have their own specifics. Initially, they were used as insulation, but later they began to be used as building materials.

Why plaster aerated concrete walls

Aerated concrete blocks are easy to operate: they are light and warm. That's why they are easy to cut to the required size... This quality can be successfully used for plastering walls in rooms with high humidity. But it is very difficult to fix the finishing layer on a smooth surface, therefore it is recommended to pay special attention to the choice of building mixtures for plaster.

In general, indoor aerated concrete plaster performs the following functions:

• protection of the surface from sudden temperature fluctuations;
• improvement of thermal insulation properties;
• ensuring vapor permeability;
• protection from dampness.

It is required to take into account that aerated concrete, like foam concrete, have a cellular light structure. That's why violations of the technology of plastering walls from aerated concrete lead to a violation of air circulation, and as a result - to a decrease in properties.

Properties and features of types of plasters

There are several classifications of plaster mixes.

According to one of them, plaster can be:

• dry (plasterboard finishing);
• wet (finishing with dry mixes).

Each of them has its own properties and characteristics.

Plasterboard finishing is a quick way to fix minor defects.

But it has a number of disadvantages, among which the main ones are:

• reducing the volume of the room;
• short service life;
• high price.

Therefore, in order to avoid these disadvantages, you should pay attention to wet plaster. It is more often used to eliminate gross defects. Correct and high quality coating with such a solution is durable and can hold out for a long time... It is moisture resistant and independent of temperature changes. These qualities allow it to be used in rooms with high humidity, such as bathrooms, basements or garages.

Depending on the composition of the mixture, wet plaster can be based on:

The surface plastered with a cement mixture is the most durable. But it should be borne in mind that maximum strength is achieved one month after application of the solution... It is most often used in combination with various fillers, of which sand and limestone are the most common.

Cracks rarely occur on such surfaces. Basically, this is due to an improperly prepared solution or to forcing the time to dry the surface. Because surfaces treated with this solution dry for a long time, it is better to start finishing work 10-15 days after leveling... This creates certain difficulties.

If it is necessary to complete the repair in a short time, it is better to use gypsum-based plaster. It can dry and harden in a few hours. Among the advantages, mention should be made of the thermal insulation properties and the ability to eliminate excess moisture in the room.

It is due to its moisture resistance that it is widely used in the bathroom for finishing work. Of course, working with this kind of plaster requires skill, because the setting time is only 30-50 minutes, during which it is necessary to complete all the work.

This disadvantage is easily leveled with the help of additives, and they are a mandatory component.

You can find out more about the composition of the dry mix and the specifics of its use on the package.

Work technology

As noted above, aerated concrete surfaces have specific features. Therefore, not all types of plaster solutions can be used on them. In addition to the poor adhesion of this solution to the wall, aerated concrete strongly absorbs water, which subsequently leads to the appearance of small cracks... Even a well-applied primer is not able to cope with this problem.

It should be noted that cement-sand plaster mixture by an order of magnitude reduces the vapor permeability of the surface... This worsens the indoor climate. In contrast to them, aerated concrete blocks have excellent vapor permeability, therefore, when using a cement-based solution, this property may disappear. Therefore, you should use a vapor-permeable plaster for aerated concrete walls.

Thus, when plastering walls from aerated concrete outside and inside, it is better to use building mixtures designed specifically for aerated concrete.

Materials and tools

For plastering walls made of aerated concrete, use the following set of tools and materials:

• mallet;
• wall chaser;
• carriage;
• ladle;
• grout;
• hacksaw for aerated concrete;
• container for solution;
• bucket for applying glue;
• emery for leveling irregularities.

This basic set of tools is enough to get the job done.

It must be borne in mind that outside plastering of aerated concrete walls should not be carried out in winter so that the surface has time to absorb a certain amount of moisture. For internal work, this is not essential.

Before plastering, it is imperative to prepare the surface..

Surface preparation

• cleanse from any kind of contamination;
• clean up chips;
• apply a layer of putty;
• apply a special primer to aerated concrete;
• fix the reinforcement mesh to the surface.

Because the level of adhesion of aerated concrete blocks is much lower than that of cement blocks; it is recommended to use reinforcing meshes. But it is possible to replace it with the usual "netting" mesh. Sometimes, grooves are applied to the wall surface to increase the stickiness.

Methods and ways of working

Plastering process for aerated concrete is similar to plastering on other surfaces.

The works are as follows:

• install beacons;
• scoop up the solution with a ladle and throw it onto the surface;
• remove beacons.

Work must be done from the bottom up, avoiding the formation of voids.

Finishing works

After applying the solution to the wall, it needs to dry out. Finishing work includes leveling the dried layer, for which you can use small spatulas.

After complete drying, the surface is almost ready for painting... Experts advise using any breathable elastic paint. To increase the durability of the coating, you can subsequently apply a small layer of water repellent.

Professionals advise taking into account a number of nuances that facilitate the performance of work and lengthen the service life.

Among the main ones are:

• the plaster mix is ​​better attached to aerated concrete blocks, which are made using cutting technology due to its inherent roughness;
• aerated concrete plaster outside and inside must have the correct ratio of external and internal layers;
• the wall under the outer layer must not retain moisture, that is, the air must be able to circulate freely. In the opposite case, due to freezing and thawing in winter of plaster for aerated concrete, the facade surface will be covered with cracks and mold.
• at the beginning of work, it is required to apply the required amount of solution to the wall by spraying and only then apply the main layer.

Cost of work

A large number of dry mixes for internal aerated concrete plastering are presented on the construction market. Before purchasing, it is recommended to carefully study the main characteristics of the mixture indicated on the package. Average, the price varies from 280 to 400 rubles per package of 30 kg.

The cost of work, on average, is 500 rubles per 1 m2... Obviously, when doing work with your own hands, it is possible to save money.

More details about internal plastering of aerated concrete walls can be seen in the video:

Plastering of aerated concrete walls is a justified measure. , like the foam block, despite all its advantages, the material is hygroscopic. This means that it absorbs moisture easily. Therefore, the aerated block house must be protected from the weather. If the gas block gets wet in the rain and then dries up, it will not lose its properties. And if it gets wet in winter, then the water accumulated in the pores of the aerated concrete will freeze and expand. This is fraught with the appearance of small cracks that spoil the view, as well as the occurrence of more serious damage.

Conclusion: protecting aerated concrete outside from freezing, moisture, snow and other atmospheric precipitation is a necessary measure. During and during the winter storage (if necessary), this function can be performed by a film stretched over the walls. During the operation of the house, it can be any facing material for the external decoration of the facade - plaster for aerated concrete. The main thing is to create conditions for vapor permeability so that the aerated concrete "breathes".

Exterior decoration of aerated concrete house, in addition to protecting the blocks, allows:

• to strengthen the heat and sound insulation of the walls;
• eliminate the possibility of walls getting wet;
• protect the house from sudden changes in temperature;
• decorate the facade of the house (decorative plaster for aerated concrete).

One of the most popular ways of exterior decoration of an aerated concrete house is plastering. Therefore, questions often arise, for example, how and with what to plaster aerated concrete, to which we will try to answer as fully as possible. We will conduct a comparative review of the characteristics of the best mixtures for facade decoration, and also describe the technology for plastering walls in the form of step-by-step instructions that are understandable for beginners without construction experience.

Aerated concrete plaster

Summarizing the experience of builders and owners of aerated concrete houses, we can conclude that three types of finishing materials are used for plastering walls made of aerated concrete:

Cement-sand plaster for aerated concrete

Is it possible to plaster aerated concrete with cement mortar?

No. Regardless of whether the aerated blocks were laid on cement or glue. In general, plastering aerated concrete with cement mortar is extremely undesirable, because aerated concrete is very smooth and the mortar does not stick to it, and also strongly absorbs water from the solution.

The reasons why it is impossible to plaster a house from aerated concrete with cement mortar:

• Cement slurry has a lower vapor permeability index than aerated block. This is the most important reason why you shouldn't use it. In the case of wall finishing made of aerated concrete, professionals have a rule, you can use only that finishing material that, in terms of vapor permeability, does not differ from the aerated concrete itself, or has a higher indicator than it. Only in this case, the optimal microclimate of the aerated concrete house will be maintained.

Note. For the same reason, it is undesirable to use rigid insulation (polystyrene and expanded polystyrene) to insulate a house from aerated concrete.

• Cement-sand mortar has a high moisture content. To mix the components into the sand-cement mixture, you need to add water. It is also obvious that aerated concrete, having a significant moisture absorption rate, will tend to absorb this water from the solution. This, in turn, reduces the quality of the mortar applied and its ability to adhere to the wall. After all, concrete gains strength only if it dries evenly and slowly.

Remember, the foundation must be periodically moistened and covered with foil to ensure even drying. So why should he behave differently on the wall? The primer saves the day, but not much. The appearance of a cobweb of small cracks on the plastered surface of aerated concrete cannot be avoided.

Note. In order to save money, you can mix a cement-sand mixture and a special mixture for finishing aerated concrete blocks in a ratio of 1 to 1. But is there any need for such savings that will significantly reduce the speed of work, and the finished surface will not be 100% of high quality.

• Plaster mortar has poor adhesion. It cannot provide high-quality adhesion to aerated concrete. One of the reasons can be considered the weight of the solution and the presence of large impurities in its composition.

The adhesion index (adhesion, adhesion of surfaces) can be increased by adding lime to the classic recipe for cement mortar (proportion: 8-10 kg of lime per 100 kg of concrete).

Cement-lime plaster can be purchased as a ready-made dry mix. For example, dry construction cement-lime mixture KREPS Extra-light (240 rubles / 25 kg), Osnovit Startwell T-21 (208 rubles / 25 kg), Baumit HandPutz 0.6 (300 rubles / 25 kg).

• compulsory application of a finishing layer. Because it is difficult to make a smooth surface using a sand-cement mixture.

Is it possible to plaster aerated concrete with glue for aerated concrete?

Also undesirable. Despite the fact that it was developed taking into account the specifics of aerated concrete, it is intended for application in a thin layer and the formation of seams, and not for external wall decoration.

Violation of the vapor permeability of aerated concrete will lead to problems such as cracking of the finishing layer, the manifestation of traces of seams (disappear after drying), the appearance of mold.

Gypsum plaster for aerated concrete

Advantages of gypsum-based plaster:

• high drying speed;

• no shrinkage of the solution;

• the ability to make a smooth surface;

• no need to apply a finishing layer.

Disadvantages of gypsum plaster:

• mediocre vapor permeability;

• higher, in comparison with a special mixture, the water content required for mixing the mixture (10-15 liters per bag);

• quick wetting during rain or snow;

• the likelihood of spots on the surface that have to be painted over.

Despite the disadvantages, plastering the walls with plaster is an acceptable option for finishing aerated concrete. Well proven: gypsum vapor-permeable highly plastic plaster mix Pobedit Velvet G-567 (previously Pobedit-Aegida TM-35 for 320 rubles / 25 kg.), Knauf Rotband (360 rubles / 30 kg) and Bonolit (290 rubles / 30 kg).

Facade plaster for aerated concrete

The most effective material for plastering exterior and interior walls made of aerated concrete. Plaster for facade work has a number of characteristics, including the vapor permeability indicator, which is identical to that of aerated concrete (for most types of plasters), good adhesion to the base, and a beautiful appearance.

When choosing what to plaster aerated concrete, it is best to stop at a high-quality special mixture. In addition, the use of facade plaster makes it easier to decorate aerated concrete house with your own hands.

What plaster is better to plaster aerated concrete walls?

There are a variety of ready-made mixtures for plastering aerated concrete walls on the market. To make the right choice, you should pay attention to the characteristics of the plaster:

• vapor permeability;

• the required amount of water for mixing the mixture (no more than 0.2 liters per 1 kg of the mixture);

• boundary values ​​of plaster application thicknesses (minimum and maximum);

• adhesion to the substrate (minimum 0.5 MPa);

• resistance to low temperatures;

• resistance to cracking;

• pot life of the solution. The more, the easier it is for beginners to work with it.

And only when choosing between two equivalent mixtures, one should be guided by the price, in this matter it decides not the last role, but also not the key one.

According to reviews, aerated concrete wall plaster outside the room is popular among users - a dry mix with Ceresit CT 24 plasticizers (380 rubles / 25 kg), leading in terms of price / quality.

Material prepared for the site www.site

When can aerated concrete walls be plastered?

Since aerated concrete easily absorbs moisture, it is better to protect it immediately from getting wet. Again, it is not critical if the material gets wet, but you should not allow the moisture in the gas block to freeze. This can lead to weakening and the appearance of unwanted cracks.

There is no need to rush to the cladding either. After laying aerated concrete, the walls should dry well. That is why aerated concrete walls are plastered only in the warm season. In the case of using a concrete-sand mortar as a binding element when laying aerated concrete blocks, the drying time increases, since such a seam is several times thicker than a seam made with a special adhesive mixture.

If it is not possible to finish the house during the warm season, you need to cover the walls with any deep penetration primer. For example, Ceresite ST-17 (549 rubles / 10 l).

The primer will reduce water absorption. It is also advisable to cover the walls with polyethylene left over from the packaging of pallets with aerated concrete.

According to the craftsmen, the most preferable time for finishing work is the period when the night temperature exceeds 0 ° C. For central Russia, this time is from late March to early October.

From which side do you need to start finishing the house from aerated concrete?

Let's conduct a comparative analysis of several popular options for the sequence of wall decoration.

Option 1
First, the exterior decoration of the house is made of aerated concrete

There is an opinion that the most important thing is to protect the gas block from the street, because it picks up moisture. However, this is not the case, even after standing without protection (but primed) the whole winter, the gas block will "give back" the accumulated moisture in the spring. And if it is closed from the outside, where will the vapors be directed? That's right, inside the room. This will not only increase the drying process and delay the execution of interior decoration, but also fraught with the appearance of cracks inside the room.

Option 2
First, the interior decoration of the house is made of aerated concrete

With this approach, in the process of finishing work, the pores of the aerated concrete block are partially closed. And if you first plaster them from the outside, the accumulated water vapor will simply have nowhere to go. Moisture settling inside the block will contribute to its destruction. Plastering walls made of aerated concrete indoors will avoid this situation.

After the plaster has touched the inner walls and has dried well, you can start finishing the outer walls.

Option 3
Simultaneous interior and exterior finishes

The method is the least preferred. Moisture, which will be "pulled" by the gas block both from the outside and from the inside, will not be able to get out quickly.

Despite the fact that aerated concrete plaster has good vapor permeability, the rate of this process is not so high. This is especially critical in the cold season (at night temperatures below zero). In this case, water vapor will settle in the form of condensate and, as a result, can lead to peeling of the plaster layer from the aerated concrete. In practice, this option will lead to the destruction of the gas block as quickly as possible.

In theory, each of the options is eligible for implementation. But, the second is correct.

How to plaster aerated concrete walls with your own hands

We figured out the question of whether it is possible to plaster aerated concrete. Now it is important to understand how to do this correctly, without prejudice to the aerated concrete to allow moisture to pass through.

Plastering of aerated concrete blocks does not fundamentally differ from performing work of a similar type on other materials. The putty application technology differs in only a few details, which will be emphasized.

Internal plaster of aerated concrete walls

Technology of finishing aerated concrete with plaster indoors - sequence of works:

1. Preparation of the base

It starts with leveling the walls - removing irregularities is done using a planer or aerated concrete grater. This work is recommended to be performed even at the stage of building a house, but many neglect this, saving time. In principle, this stage can be omitted, which will lead to a significant increase in the consumption of the mixture and an increase in the thickness of the applied layer. In turn, this is fraught with plaster flaking and cracks.

2. Application of the primer

There are often recommendations that the primer should be diluted 1 to 1 with water. reduces its ability to increase surface adhesion. There are more reliable ways to save money. For example, remove dust from a surface by applying clean water to it. Apply water with a brush or roller as if it were a primer. And then, after drying, a primer is applied.

The choice of a primer depends on the purpose of the room to be finished. For a corridor or hallway, any universal primer is suitable, for example, Unis (250 rubles / 5 l). For the bathroom and kitchen, it is advisable to use a deep penetration soil, for example, Prospectors (450 rubles / 10 l).

3. Installation of beacons

Beacons, as the name suggests, determine the thickness of the mortar application. They are set to the width of the rule. The accuracy of the installation is determined by the building level.

4. Throwing "fur coat"

This is the name of the method of applying the first layer of plaster. The work is carried out from the bottom up. Next, you need to lean the rule on the lighthouses and align (stretch) the sketched layer along them. If voids appear, they must be repaired immediately. The main thing is that the plaster does not peel off from the base. If this happens, you need to remove the plaster, treat the surface with a primer and apply the solution again.

5. Treatment of the first layer

After the first layer of plaster has dried, it must be slightly moistened (with a spray gun) and leveled. Since the beacons serve as bridges of cold, it is advisable to remove them at this stage, and seal the places (recesses after dismantling) with mortar.

6. Forming corners

For the device and reinforcement of the outer corners, a perforated corner with a mesh is used.

7. Finishing

Grouting (if necessary) and painting of aerated concrete walls are performed. In the case of wallpapering, no finishing is required.

For aerated concrete paint, there are also requirements for vapor permeability. Such properties are possessed by paints for interior work based on PVA, latex, acrylic emulsions, organic solvents and cement paints.

An example is ESKARO AKZENT (antibacterial paint, RUB 325 / 0.9 kg). At the same time, for rooms with high humidity, you should use special paints, for example, AquaNova Premium (282 rubles / 2.8 kg)

How to plaster aerated concrete walls correctly - video

Exterior wall plaster made of aerated concrete

Decorative plastering of the facade of a house may involve the application of plaster for external use in a thick layer (thick-layer finishing) or in several layers (thin-layer plaster).

Consider a multi-layer option for applying a thin-layer facade plaster for aerated concrete. Its peculiarity is the creation of three thin (no more than 10 mm) layers.

Outside plastering technology:

• preparation of the wall. Includes leveling the surface to reduce the consumption of the mixture and the thickness of its application;

• priming the surface;

• application of a thin layer of plaster mixture (up to 5 mm). Its purpose is to serve as the basis for attaching the mesh;

• reinforcement of plaster with mesh;

How to properly reinforce plaster

As a reinforcing layer, a metal mesh with small cells can be used, for example, a steel mesh with a wire diameter of 0.1 mm, and a cell pitch of 0.16x0.16 mm (average price is 950 rubles / m2 = 2 850 rubles / roll) or fiberglass mesh (for example, reinforcing fiberglass mesh with a cell pitch of 50x50 mm (approximate price of 17.60 rubles / sq. m = 880 rubles / roll).

The mesh is fastened with an overlap of 50 mm. At the same stage, the corners of the building are formed using a perforated corner with a mesh. The mesh helps prevent cracks in the plaster due to building shrinkage. Thus, the plaster of the facade made of aerated concrete will not be covered with a web of small cracks. The mesh is sunk into the applied solution with a spatula. It is especially important to install the mesh in areas of high voltage, near windows and doors.

Advice. Fastening the mesh to a dry wall will have no effect, because the mesh will be fixed to the base with self-tapping screws. In the case of its installation on a solution, it forms a monolith with the solution, and will move with it.

• alignment of the plaster layer on the grid;

Next, you need to wait until the first layer is completely dry. Otherwise, it may fall off under the weight of the second layer. Since this method involves a thin-layer application of the solution, you will need to wait 3-4 days. The thicker the layer, the more. You can check if the layer is dry with water. If you splash on the wall and the water is absorbed, then it's time to get to work.

Note. When the plaster dries, it must be protected from the influence of environmental factors (moisture, snow, rain).

• applying a second layer of plaster. This layer is considered a leveling layer, therefore, increased attention is paid to the evenness of the application and the formation of a smooth surface;

• application of the third (finishing) layer of plaster mixture, followed by grouting, if necessary;

• painting a plastered aerated concrete wall or applying a textured plaster mixture, for example, Pobedit-Bark beetle (340 rubles / 25 kg).

  For painting aerated concrete, only exterior paints are used. For example, Nova-Fasad (590 rubles / 7 kg), Gasbetonbeschichtung from Dufa (2674 rubles / 25 kg), ROLPLAST Gordianus (3700 rubles / 10 kg), Dyotex (concentrate, 5500 rubles / 15 kg).

• application of a water repellent. This is a special solution that professionals recommend to be applied one year after staining, after the end of all facing work. The water repellent will give any surface additional water-repellent properties. A special water repellent for aerated concrete "Neogard" (350 rubles / 1 liter) has proven itself well.

Aerated concrete putty

When deciding how to putty aerated concrete, you need to know that there are three types of finishing materials on the market that are similar in purpose, but differ in their composition. All this, facade plaster for aerated concrete, sold in the form of a ready-made mixture. Designed for thin-layer finishing of plastered surfaces.

Ready-made silicate plaster, for example, Baumit SilikatTop Kratz Repro 3.0 mm (RUB 3,700 / 25 kg)

Conclusion

Consistently performing work on plastering walls made of aerated concrete and using only vapor-permeable materials, you can provide a reliable finish that will decorate the facade of the house for more than one year. And planned repair work will be reduced to periodic painting, to restore the color of the paint and eliminate small cracks.

Aerated concrete houses are popular due to their ease of construction and the relatively low price of gas blocks. However, lightweight porous material is defenseless against moisture, frost and strong winds. One of the available methods of protection is aerated concrete plaster. Information about how the plastering inside and the plastering of the facade is carried out will be useful not only for those who have recently brought gas-block walls under the roof, but also for those who are engaged in repairs.

Features of aerated concrete

To know which mixtures to choose for plastering walls from aerated concrete blocks, you need to study the features of this material. They are due to production technology. There are two ways to obtain a porous artificial stone - autoclave and natural hardening (hydration or non-autoclave).

The differences are:

• color (hydration - pronounced gray);
• geometric accuracy (autoclave more precisely);
• strength (autoclave values ​​are higher);
• density, thermal conductivity (the optimal ratio of indicators for an autoclave);
• fragility (hydration is in the lead);
• durability (autoclave is in the lead).

In the manufacture of aerated concrete, lime, quartz sand, cement, a gas-forming reagent (usually a paste or aluminum powder) and water are mixed. When mixing the solution, lime reacts with aluminum, releasing hydrogen. Gas, released throughout the volume, forms small, numerous pores. And since light hydrogen tends to go out, then passages arise between the pores.

Thus, the aerated concrete structure is dotted with small pores, between which air channels pass. Because of them, the material is characterized by increased water and vapor permeability.

Regardless of which method was used to obtain the porous material, its disadvantages are:

• high water absorption;
• the ability to corrode metal fasteners;
• poor adhesion;
• unaesthetic appearance;
• blow-through (through channels, retaining heat in calm weather, lose their insulating properties in windy weather);
• rapid destruction in the absence of a protective finish.

Therefore, aerated concrete especially needs to be coated with materials suitable for it.

Applied methods of protection:

• ventilated facade (porcelain stoneware, lining, siding, etc.);
• "Wet facade";
• protective staining;
• facing with brickwork;
• plastering.

In the case of choosing plaster protection, you should know which is the best of the existing finishing materials.

Basic requirements for plaster

The compositions used in the room for the protective plaster of the walls made of aerated concrete should contribute to the creation of a healthy microclimate. Facade plaster for aerated concrete must also be weather-resistant, have the ability to withstand temperature surges (resistance to low temperatures), and reduced water permeability.

Aerated concrete plaster should have the following properties (regardless of the place of application):

• reliable adhesion to aerated concrete surface (≥0.5 MPa);
• vapor permeability;
• strength;
• water demand no more than 200 ml per 1 kg of SS (dry mix);
• fire resistance;
• environmental friendliness;
• biostability;
• durability;
• decorativeness.

What plaster is better to plaster aerated concrete walls

Taking into account the above requirements, plastering compositions have been developed specifically for aerated concrete blocks.

They are divided into:

• mixtures for interior work;
• universal compositions;
• facade plaster.

Of these compositions, aerated concrete plaster for outdoor use is the most resistant in all respects, since it is operated in the most unfavorable conditions.

By appointment, the compositions are:

• ordinary (for alignment - rough finish);
• special (perform additional functions, for example, etc.);

By the type of binding base:

• and etc.

For beginners, information about the expiration dates of the solution is important. The short term requires the plastering to be carried out quickly before the mortar starts to set.

Liquid glass is used as a binder for silicate plaster. It is a durable material that has such advantages as:

• vapor permeability;
• durability;
• resistance to aggressive substances in a gas-polluted atmosphere;
• strength;
• non-susceptibility to biological damage;
• resistance to prolonged exposure to UV light;
• fire safety;
• strong adhesion to the base;
• non-shrinkage during hardening;
• easy cleaning (dirt is washed off by rain or watering from a hose).

The silicate coating perfectly protects porous and “soft” materials.

• it requires primers (as well as paints and varnishes) on a related basis;
• this tool is not cheap;
• poor palette of ready-made mixtures;
• requires work skill, since the shelf life is limited (presents a problem for beginners);
• under the influence of precipitation, the coating darkens, for a while it becomes spotty;
• work clothes are not cleaned after plastering.

For interior decoration, they are practically not used. Produce ready-made and dry mixes.

Incompatible with finishing materials based on latex, silicone, acrylic.

A relatively new binder - silicone - is successfully used in plastering compounds in the form of silicone resins. The only significant drawback is the high price.

Forms coatings:

• vapor permeable;
• very durable;
• durable;
• highly elastic (cracks do not form even when cracks form in the walls);
• firmly adhering to any surfaces (except for metal bases);
• resistant to chemicals;
• are not affected by bioorganisms;
• retaining strength and appearance at high temperatures;
• with unlimited layer thickness;
• not collecting statics;
• easy to clean;
• hydrophobic.

The application is universal.

Acrylic aerated concrete plaster

It gained popularity due to the attractive combination of price and quality. Created on the basis of acrylic derivatives - acrylic resins.

• elastic;
• durable;
• environmentally friendly;
• waterproof;
• workable;
• durable;
• has a rich palette;
• not susceptible to damage by fungi, rot, mold;
• washable from a hose.

• accumulates statics;
• low vapor permeability;
• not resistant to flame;

Additives are used to level the disadvantages. However, these mixtures are not used in bedrooms, living rooms.

Cement-sand

Immediately dismiss the idea of ​​using conventional cement compositions. For example, standard (DSP) are too dense and heavy for brittle aerated concrete, due to low adhesion cracks in the surface are inevitable.

The most important reason why it is impossible to plaster CPB, the vapor permeability indicators of CPB, they are lower than that of aerated concrete. The creation of an optimal microclimate for living becomes impossible.

Leading companies have modified the cement mix, making CPB with additives suitable for porous substrates.

Lime-cement

Low vapor permeability and poor adhesion to aerated concrete of cement compositions are eliminated by adding lime to them. Such compositions can be prepared with your own hands, this will save your budget.

• quickly hardens, gaining strength;
• non-shrinking, cracks do not appear when solidified;
• has vapor permeability;
• plastic, easy to fit, keeps the given shape;
• adheres firmly to aerated concrete;
• does not give its water to the porous base;
• environmentally friendly;
• fireproof;
• forms coatings with low weight;
• maintainable;
• easy to sand;
• able to form a smooth surface.

• "rabies";
• low frost resistance;
• short lifespan.

Of all the compositions, this one is the best for plastering aerated concrete surfaces of residential premises. Since aerated concrete walls, partitions, as a rule, have a flat surface, the plaster coating can be made to the minimum possible thickness. For gypsum mixtures, this is 1 mm. In the case of cement mortars - 10 mm.

Gypsum compositions with perlite sand are perfect for insulating aerated blocks.

Most popular manufacturers

Plaster mixes for finishing aerated concrete are in the lines of all major manufacturers of plasters. Mixes of popular brands are distinguished by the exact correspondence of the qualities to the declared indicators.

Among the popular manufacturers are the following companies:

• the German concern Henkel (develops and manufactures plasters under the Ceresit brand);
• Austrian brand Baumit;
• Knauf, which originally produced gypsum mixes, also produces cement-based mixes;
• Krasland company;
• Bolars (Uniplast mix);
• a number of plasters for aerated concrete are produced by the Pobedit company.

From the Ceresit line for aerated concrete, the CT 24 and CT 77 brands and others are most often used. CT 24 is a lightweight, frost-resistant, vapor-permeable, cement-based plaster mixture for leveling universal use. ST 77 - facade acrylic aerated concrete plaster, ST 35 - decorative mixture "bark beetle" for facade use.

In the Baumit line, the popular cement-lime compound Baumit HandPutz for universal use, silicone compound SilikonTop, silicate mixture SilikatTop, acrylic Nanopor Top.

From Knauf mixtures for aerated concrete walls, gypsum Knauf-Profi, gypsum polymer Eisberg, gypsum with polymer additives Rotband, Goldband, cement Grunband (heat-insulating), Sevener are suitable.

The Krasland company produces compositions specifically for aerated concrete walls, for example, Aerated Concrete-2.

Features of plastering

Aerated concrete blocks are brought to the construction site immediately after production, when they are still full of unweathered moisture (up to 30%). During installation, water from the masonry mortar and precipitation enters the blocks. Therefore, the walls of the newly erected structure are filled with moisture. To dry out, they need to stand under the roof for at least six months. Aerated concrete also shrinks in the first year.

Therefore, the new building is not scuffed. It is also impossible to simultaneously plaster aerated concrete inside the house and outside the room (you need to give the walls time to dry).

Aerated concrete walls are first plastered indoors, and after a few months - along the facade.

In regions with a damp climate, they do not wait for the next season for plastering. Highly plastic compounds with high vapor permeability are used.

The vapor permeability of the plaster coating outside the building should be higher than that of the interior decoration.

How and what to plaster aerated concrete inside the house

It is easier to choose a composition for internal plastering of aerated concrete walls than for an external one, since the choice of mixtures is wider. Compositions are suitable not only for indoor plastering, but also mixtures for outdoor work. In addition, there is the possibility of using gypsum compositions indoors. The use of compositions with a vapor permeability lower than that of aerated concrete is encouraged. In damp rooms, denser compounds or waterproofing mixtures are used.

There are some selection problems. They arise if the facade was insulated with expanded polystyrene or polystyrene foam (without a ventilation gap). These materials are practically vapor-tight, the removal of moisture from aerated concrete walls into the room is also unacceptable. More about or read in our articles.

Since moisture accumulates inside the wall, they block access to aerated concrete, using plastering compounds inside the room with a vapor permeability much lower than that of aerated concrete blocks. That is, cement, dense plaster. In this case, the role of the ventilation system in the removal of moist air from the room increases.

Suitable for facades: silicate, cement-lime, silicone mixtures, for premises - cement-lime, gypsum-perlite, gypsum-lime compositions.

If the plastering inside is carried out first, then in addition to the choice of plasters suitable for aerated concrete, measures are taken to prepare the base, which has very low adhesion and the ability to easily and in large quantities absorb water. The walls must be treated with deep penetration primers, observing the points of the manufacturer's instructions. Even small excess of water must not be allowed in the primer and plaster.

To cope with low adhesion, when plastering walls from aerated concrete indoors, apply a rough plaster layer (at least 0.5 cm) and apply fiberglass or polyurethane reinforcement.

How and what to plaster aerated concrete outside the house

When deciding what is better to plaster aerated concrete outside, they rely on the rule that the vapor permeability of the external material should be equal or greater than that of aerated concrete. Compositions must necessarily be designed for facades or universal. Outside the house, the loads and impacts on the surface of the structure are higher. Therefore, reinforcement is indispensable.

Outside the building, it is better to use mineral wool, heat-insulating plaster or drywall for insulation.

A year after the application of the finishing layer, it is covered with a hydrophobizing compound, which gives the surface a water-repellent property.

Optimal conditions for plastering

To obtain a plaster coating with the desired qualities, a number of conditions must be met, including the conditions under which plastering is performed. For plastering aerated concrete walls during interior work, the temperature range is from +5 to + 30 ° C. Drafts and humidity over 60% are not allowed in the room. It is more rational to guess the beginning of plastering by the end of the heating season.

For external aerated concrete plaster, a time is chosen when the temperature is kept at least + 8 ° C for several days. Do not plaster the facade at a humidity of more than 80%, possible frost, in windy or hot weather. The place of finishing works is protected from the sun, rainfall.

If the season ends, and it is not possible to plaster the facade, then it is covered with a primer (a deep-penetrating agent is taken) in two passes and left until spring. In addition, the walls are sometimes covered with foil for the winter.

Plastering technology for aerated concrete facades

How to plaster walls made of aerated concrete blocks?

For aerated concrete walls and partitions, two methods of applying solutions are used:

• thick-layer (the solution is applied in one layer, after which it is rubbed);
• thin-layer (the mixture is applied in several passes).

The general step-by-step picture of performing plastering is as follows:

1. The base is prepared.
2. Apply a primer.
3. Prepare a solution or prepare a ready-made mixture.
4. The first layer is applied, reinforced, treated with a notched trowel, and dried.
5. A second layer is applied, leveling the comb of the first. Dried.
6. The third (smoothing) layer is applied. Overwrite. Dried. Grinding. The layer is performed if it is needed for finishing, for example, painting.

Surface preparation

The precision with which the aerated concrete blocks are made allows builders to perform fairly even laying. Such walls need preliminary preparation. As a rule, the blocks are placed on the adhesive. At the same time, the blocks do not damp as much as when laying on a mortar, and the walls dry out faster.

During preparation, if the glue solution protrudes from the plane of the wall, it is shaved off with a trowel designed for aerated concrete, or with a plane. You can also cut off some of the tabs. If there are chips or cracks, they are filled with an adhesive to which you can add dust generated when cutting blocks. After filling the cavities with a narrow spatula, remove all excess and dry the adhesive. After that, the surface is rubbed.

The preparation of aerated concrete for plastering is completed by sweeping away the dust.

Padding

A little about what can be used to prime aerated concrete before plastering.

Of the compositions, the most popular are the deeply penetrating Knauf Grundiermittel, Aerated concrete-contact-1, Siltek E-110. Acrylosiloxane primer for aerated concrete makes the surface of the blocks water-repellent. Apply a layer of primer with a roller or brush in two to three passes with drying. In areas with a dry climate, one layer may be sufficient; in areas with a humid climate, 3 layers are applied.

Do not dilute the primer with water!

Aerated concrete plastering and reinforcement

Newbies are wondering if a grid is needed. If the solution is applied in one layer up to 10 mm, then with a high-quality primer in the room, they do without reinforcement. However, for facade cladding, mesh is an additional strength that cannot be dispensed with.

A fiberglass mesh (resistant to alkalis!) With meshes of 3x3 mm is placed on a freshly laid layer of mortar (at least 5 mm) and embedded in it with a spatula. The fabrics are connected with an overlap of 5 cm. A layer with a mesh is formed with a notched trowel, creating horizontal ribs, then dried.

If the thickness of the coating is ≥7 mm, beacons are used. When working on the street, two more layers are applied: the second is leveling, the third is to form a solid, smooth surface. The latter is rubbed with sandpaper or an abrasive mesh.

Finishing layer

For wall decoration, plastering, painting or wallpaper is most often used. These materials must be vapor permeable. The surface of the dried plaster coating is primed before applying the finish. The technology of plastering walls with decorative compounds is described in the section.

Thermal insulation of walls made of aerated concrete

Temperature drops, as well as minus values, are harmful to aerated concrete. The strength decreases, the structure collapses. Basically, wall insulation made of aerated concrete is done outside the structure. Mineral wool is used as a heater. And since this material is soft, plastering on top of it is not possible.

Plastering of walls from gas blocks is performed only to level the surface for a snug fit of the mineral wool to the wall. In order to lay and attach the insulation, a metal ebb and wooden bars are mounted on the wall (the distance is 2 cm less than the width of the mineral wool canvas). The canvas on glue-foam is attached to the wall or glue and umbrella dowels are used.

On top of the insulation, a vapor barrier film is applied, which is attached to brackets to the bars, and covered with an adhesive solution. Perforated corners with a mesh are installed in the corners. Then the ventilation facade is mounted.

When insulating with mineral wool, acrylic mixtures are not used.

If the insulation of the outer walls is not possible, the insulation is carried out indoors, using warm plaster or gypsum plasterboard (gypsum plasterboard) for this.

Presenting the material on plastering aerated concrete walls, we tried to answer the frequent questions of newcomers - owners of a private house. Now you have an idea which aerated concrete plaster is best, how to plan the plastering correctly, how to plaster a block house inside or outside.

Gas silicate blocks are an excellent building material. Their designs are warm and reliable. But after construction, the question arises: how is the plastering of building gas silicate blocks from the inside carried out? There is a special technology for performing work, which we will consider. This will help to quickly and efficiently prepare the walls made of gas silicate blocks for interior decoration.

Requirements for plaster

The range of products for work is quite large, but not all of them are suitable for gas silicate plaster. The surface of the material is porous, which causes difficulties. Consider the requirements for the plaster mix:

• vapor permeability, due to which the wall of gas silicate blocks will breathe;
• if the work is carried out outside, then the plaster is selected to be moisture-resistant and frost-resistant in order to withstand atmospheric influences;
• high quality of adhesion (adhesion to the surface);
• good strength;
• elasticity, so that it can be easily applied, and during operation, the plaster does not crack;
• resistance to high temperatures, for compliance with fire safety.

All this is important to consider before plastering gas silicate blocks. Most of the modern blends are suitable for almost all criteria. If we talk about finishing the gas silicate blocks from the inside, then it is much easier, since the composition does not have such an aggressive effect.

Which mixture to choose

The question arises, how to plaster the gas silicate blocks inside? Some people prefer to use cement-sand mixtures for plastering. But it's not right. There are two good reasons for this:

1. The quality of adhesion to the wall is poor. Aerated concrete, due to its porous structure, quickly absorbs all the water from the mixture. As a result, the plaster will be covered with cracks when it dries. Even a primer does not always help to get rid of this phenomenon.
2. This plaster will significantly reduce the vapor permeability of a wall made of aerated concrete blocks. The microclimate will be disturbed, and condensation will form on the walls. For walls made of brick or foam concrete, this is not so important. A gas silicate house must breathe.

Instead of a cement-sand mixture, a specially developed plaster for gas silicate blocks is recommended. She has all the necessary properties that are needed for work. For specifics, we will provide a list of popular compositions: Ceresit CT 24, Atlas Silikat, Glims TS40 Velur, Mask + MSh, Sibit. Average plaster consumption is up to 9 kg / m2.

Note! It is better to do the plaster yourself, as the price of a professional's work can bite. Plastering 1 m2 of a wall will cost 300 rubles, priming and putty - another 300 rubles / m2, reinforcement of the wall with a mesh - 100 rubles / m2, finishing painting - from 120 rubles / m2.

Nuances of working with gas silicate blocks

You cannot compare ordinary brick or concrete with gas silicate. The material has special properties. Plastering walls from gas silicate blocks has its own difficulties:

With all this in mind, you can begin the process of plastering the walls. But first, let's take care of the necessary tools and materials.

Arsenal for plaster

To begin with, the plastering work will be carried out along the lighthouses. This will make the surface perfectly flat and will simplify the task for beginners. Below is a list of tools that will be required for work:

1. Rule for stretching and leveling plaster between beacons.
2. The lighthouses themselves, made of wood or metal. These are slats or profiles that serve as a guide.
3. Roulette, plumb line, marker, level, dowels and screws.
4. A primer for gas silicate blocks for plastering is performed using a roller and a paint brush.
5. Plastering is done with a bucket or trowel.
6. To prepare the mixture, a bucket and a construction mixer are used.
7. Grater and half grater.

As for the materials, everything is simple here: primer, selected plaster, fiberglass mesh, topcoat.

Preparatory stage

It all starts with preparation. It is very important, since the end result directly depends on this. The instruction is as follows:

1. To begin with, the surface is cleaned of everything unnecessary: ​​dust, dirt, stains, old coating.
2. Then a primer is applied. It is easier to do this with a roller, and to process hard-to-reach places with a brush.
3. Alternatively, you can make notches on the wall instead of a primer. They are made with a grinder.
4. In the end, it remains to complete the installation of beacons. This is one of the difficult stages, without which the gas silicate plaster will be problematic.

The installation of beacons begins with the markings on the wall. To begin with, you need to step back 30 cm from the corner of the wall, 15 cm from the floor and ceiling and draw a straight line. Do the same on the other side. At the points where the lines end, drill a hole, drive in the dowels and tighten the screws. Align the resulting fasteners so that they have the same depth. Mark the rest of the wall, maintaining an indent of 130-150 cm from the lines.

Note! The distance from the beacons should not exceed the length of the work rule.

Then they are connected in a horizontal position with a thread, forming a rectangle on the wall. Markers mark the places where the thread intersects with the line drawn inside. A hole is drilled there, a dowel is inserted and a self-tapping screw is screwed in. It remains to pull the diagonal threads to check the evenness. All elements must be in the same plane.

It remains only to install the beacons along the drawn lines. Installation is carried out on a mortar or on fasteners. If the walls are relatively flat, you can do with fixing on the mortar, which is applied in small portions along the line with an interval of up to 20 cm. The profile is sunk into the mortar and aligned with the screwed-in self-tapping screws. The plaster can now be applied.

Plastering walls

Work begins with the preparation of the solution. Usually, the instruction is indicated on the packaging of the product. You will need a construction mixer and a mixing container. The consistency of the plaster should be like a paste. If there is no primer layer, then the wall is slightly moistened. Step-by-step instructions for plastering gas silicate blocks:

1. Using a trowel or bucket, the composition is applied to the wall in a thick layer. Work is done from below, moving up. It is not necessary to fill the entire wall, but only one section of the two beacons.
2. Further, using the rule, the gas silicate plaster is stretched and the surface is leveled. In this case, the movements should be zigzag, starting from the bottom, moving up.
3. Surplus composition is thrown up. The work is carried out until the entire section is full and perfectly aligned. Advice! The thickness of the layer depends on the location of the beacons. If the thickness exceeds 3 mm, then a reinforcing mesh is needed. She sinks into the solution. The surface must be flat and free from creases.
4. According to this principle, the entire surface of the wall made of gas silicate blocks is processed. Particular attention should be paid to the corners. They must be level and well reinforced.
5. When the wall is processed and a little dry, the lighthouses can be removed from their walls. After them, the grooves will remain without mortar. They are also filled with the mixture and leveled.
6. The evenness of the resulting wall is checked using a level.
7. When the surface is dry, you can start sanding the walls. It is performed with a grater and a half-grater.

At this stage, the plastering of the wall is completed. Further manipulations depend on the finishing decorative layer. If you plan to finish with wallpaper, painting or decorative plaster, then the surface is treated with a starting and finishing putty. After that, you can paint it or paste the wallpaper. That's all, the plastering of the gas silicate blocks has been completed.

Let's summarize

Having done all the work with your own hands, you can save tens of thousands of rubles. The money saved can be spent on furniture, high-quality finishing materials, or something else. If this is your first time doing this work, it is better to study the whole process in detail and only then do the plaster of gas silicate blocks. Doing everything with your own hands is quite real. It remains to put all this into practice.