Aerated concrete is a popular building material that produces strong, durable, warm, and resistant to various negative influences. It has an acceptable cost, and construction with its help can be done by hand even by beginners. After building a house, you need to decide what materials will be used for finishing works. Initially, the walls are covered with high-quality plaster, so it is important to understand how to plaster aerated concrete outside and inside the house, as well as how to do this work correctly.

Important! It is not allowed to use the same material for exterior and interior work, since it is important that the resulting coatings are resistant to existing operating conditions, and they differ significantly on the street and inside the house.

Types of plaster for aerated concrete

There are numerous types of plasters on the market. Not all varieties are suitable for aerated concrete, so the parameters of each material must first be studied, after which it is selected the right option for external use or for internal work.

Important! Plaster for external use must have high thermal insulation parameters, resistance to moisture and temperature changes, and at the same time must provide good sound insulation and have an attractive appearance.

There are several most popular plasters used for aerated concrete. Each option has its own characteristics, so it is important to study the parameters of any type before making a specific choice.

Cement plaster

This material is considered in demand for carrying out different types works, but it is considered unsuitable for aerated concrete. This is due to the fact that it produces smooth walls on which cement mortar does not adhere well. Also, aerated concrete has a specific ability to absorb moisture from the solution. Cement plaster has vapor permeability, which is lower than that of walls, so if it is used for finishing work, the microclimate established in residential premises can significantly deteriorate.

Also cement mortar different low rate adhesion to aerated concrete surfaces. Lime is often added to the composition to increase this parameter. If, nevertheless, this particular material is chosen for external work, then a special finishing layer must be applied after the plaster has dried, which allows you to obtain a perfectly smooth surface.

Important! If the vapor permeability of aerated concrete is impaired, this can cause various cracks, mold or traces of seams.

Adhesive intended for aerated concrete

There is a special adhesive mixture on the market designed for application to walls made of aerated concrete. It has an optimal composition for working with this material, but its main purpose is to connect individual blocks, so it is used at joints.

The material is applied in a thin layer, therefore it is not considered suitable for forming the outer layer on aerated concrete walls. It won't be possible to make the best out of it. protective coating, and its cost is considered quite high, so it is not advisable to use it for these purposes.

Gypsum plaster for aerated concrete

This material has many advantages for use on aerated concrete walls. Its advantages include:

• quick drying, so after the layer has hardened you can quickly begin subsequent finishing work;
• the coating does not shrink;
• with proper application of plaster on aerated concrete, the formation of a perfectly smooth surface is guaranteed;
• due to high quality of the material there is no need to apply a finishing coat after the layer has dried.

But this material is not without certain significant shortcomings. These include:

• not very good vapor permeability ();
• To obtain a high-quality mixture, you need enough large number water;
• if moisture or snow gets on a coating that is not protected by any additional layer, it quickly gets wet;
• Often unsightly and clearly visible stains appear on surfaces, therefore, for an attractive appearance of aerated concrete walls, it is necessary to use special coloring compounds to eliminate them.

Important! Even with many disadvantages, gypsum mortar is considered relevant for use on aerated concrete walls, but is usually used for interior decoration in rooms with low humidity.

Special facade plaster designed for aerated concrete

There is a special material on the market for walls made of aerated concrete, used for both external and internal use. The advantages of using it for a house built from aerated concrete include:

• good vapor permeability indicator, equal to the vapor permeability of the building material;
• excellent appearance of the resulting coating;
• good adhesion to aerated concrete.

It is this material that is most often chosen for finishing aerated concrete buildings. It provides a high-quality, uniform and durable layer with interesting view. But this material has a fairly high cost, so a lot of money is spent on finishing the entire house. For interior walls, the use of gypsum mortar is considered optimal.

Competent choice of plaster for aerated concrete walls

When choosing a material intended for plastering aerated concrete walls, the basic requirements and criteria that it must meet are taken into account. To obtain a truly high-quality and optimal coating, the plaster must have:

• good indicator of vapor permeability;
• resistance to low and high temperatures;
• resistance to exposure to significant humidity;
• resistance to the appearance of cracks, mold or other negative factors on the created surface;
• the duration of the solution’s viability, and this factor is most important for people who independently carry out the process of applying plaster, and who do not have experience working with such solutions.

Important! For each buyer additional important parameter is the cost of the solution, and it must correspond to its quality and properties, but it is not recommended to pay attention to the most affordable material, since it will not have optimal properties for use on aerated concrete walls.

When is plaster applied to aerated concrete walls?

Aerated concrete is considered a specific material characterized by good moisture absorption, so immediately after construction of the structure it is recommended to take care of protecting the walls from exposure to water. Getting the material wet is not considered critical, but the moisture in the aerated concrete must not freeze, as this can cause cracks or weakening of the walls.

Important! However, you should not rush, since after building a house from aerated concrete, it is recommended to give the material time to dry thoroughly.

Plaster is applied to aerated concrete only in the warm season. If a cement mixture is used in the process, then its drying time is considered significant, and this is due not only to its parameters, but also to the fact that a layer of sufficient thickness is certainly created.

If it is not possible to apply plaster in the warm season, then the walls are certainly covered with a special primer, and it is important to choose a deep penetration agent. The resulting layer reduces the water absorption of aerated concrete. It is permissible to cover the entire structure with polyethylene or other similar material.

From what part of the house does the finishing of the aerated concrete structure begin?

There are several options that determine the sequence of actions necessary to repair a house built from aerated concrete. These include:

• Exterior finishing is carried out initially, and then internal. Experts assure that first of all it is necessary to protect the building from various negative atmospheric factors that can adversely affect the condition of a house made of aerated concrete. It is not permissible for the walls to collect large amounts of moisture. However, on the other hand, in a house closed from the outside, water vapor will accumulate, which will negatively affect the duration of its drying, and difficulties may also arise with interior finishing work. This option is considered preferable for houses built on the banks of various rivers or lakes.
• First, interior finishing work is carried out. This option involves partially closing the pores in the walls of aerated concrete buildings. After interior finishing, it is not allowed to immediately carry out exterior work. The fact is that this can lead to a large amount of water vapor accumulating in the aerated concrete blocks, so moisture will settle in the walls of the house, which can cause their destruction. Therefore, external finishing of aerated concrete walls is carried out only after the plaster inside the house has completely dried.
• Simultaneous execution of work. This method assumes that both internal and external finishing processes are immediately implemented. This method is considered the least popular, and this is due to the fact that moisture will not have time to leave the aerated concrete blocks.

Important! Although modern high-quality plasters have good vapor permeability, they take quite a long time to dry, and this is especially important if the finishing of aerated concrete walls is planned for the cold season, so it is advisable to leave the process until warmer weather.

Technology of interior finishing of aerated concrete walls

The use of plaster for the interior decoration of a house built of aerated concrete is simple and clear process. It is divided into successive stages:

• Preparing the base. It is important to eliminate significant irregularities in the gas concrete walls. To do this, they are polished with a plane or special grater. It is possible to skip this stage, however, during the work you will need a large amount of plaster, which will significantly increase the cost of finishing.
• A high-quality primer is applied. It is not recommended to mix this product with water, as this action will lead to a deterioration in the quality of the material. Before applying the primer, it is necessary to clean the base from dust, for which the walls are washed plain water. The primer is applied after the aerated concrete walls have completely dried. A specific type of primer is selected in accordance with the specific room in which you have to work. For standard rooms, which include a bedroom or living room, you can choose an inexpensive and versatile material, but for a bathroom or kitchen, purchase a blue penetration product.
• Installation of beacons. The next stage involves installing beacons on aerated concrete walls. They are presented with special metal structures, ensuring a perfectly smooth plaster coating. They are usually installed using a small amount of plaster solution. The distance between them is left in accordance with the width of the rule that will be used to level the solution. Must be used during work building level, guaranteeing evenness of fixation of beacons.
• Preparation of plaster. In the process of creating the solution, you must strictly follow the instructions that are included with the material by the manufacturer. In this case, obtaining an optimal mixture with the desired consistency and homogeneity is guaranteed.
• Applying plaster using the throwing method. It is this method that is used to form the first layer of plaster. The procedure is performed from the bottom up, and the mixture is poured over the entire surface of the base. Next, the resulting layer is stretched using a rule. When voids form, they must be filled with solution. It is important that the material does not peel off, because if this happens, the plaster is removed and then reapplied.
• Processing the resulting layer. This is done only after the mixture has dried. Next, the coating is slightly moistened, for which it is recommended to use a spray bottle. Then it is carefully leveled and the beacons are removed. The resulting empty spaces are filled with plaster.
• High-quality and even corners are created. To obtain an ideal result, special perforated metal corners are used, equipped with a mesh on the sides.
• Finishing of aerated concrete walls. After the final drying of the plaster layer, finishing. To do this, the walls are covered with paints or other finishing materials.

Thus, the process of plastering walls made of aerated concrete is a fairly simple process that can be easily performed by every home owner.

Important! You can get an ideal work result only if you strictly follow the basic rules and follow the correct sequence of actions.

How to plaster aerated concrete walls outside?

Exterior finishing work for a house made of aerated concrete involves creating a fairly thick layer. Therefore, several layers are usually applied at once, and reinforcement is also performed. The whole process is divided into stages:

• walls are prepared from aerated concrete, and this process involves the elimination of large transitions and irregularities, which will have a positive effect on the cost of purchasing finishing materials;
• coating the surface with a primer;
• applying plaster, and the thickness of the first layer should not exceed 5 mm;
• reinforcement is made of a pre-purchased metal mesh equipped with small cells;
• the layer of plaster is leveled along the fixed mesh;
• a second layer of material is applied after the first has dried, and it is important to pay a lot of attention to proper leveling and obtaining a flat and smooth surface of the aerated concrete walls;
• a third layer is applied, which, if necessary, is rubbed over after drying;
• the resulting coating is painted or covered with textured plaster;
• it is treated with a water repellent, and it is usually applied a year after finishing, and the main purpose of this product is to protect aerated concrete walls from moisture.

Video: plastering aerated concrete

Thus, applying plaster to walls made of aerated concrete is a simple process. It can be easily done both inside and outside the house. To obtain a high-quality result, it is important to carefully study the instructions and strictly follow consistent actions. To others important point creating an ideal coating for aerated concrete walls is right choice the plaster itself, which must correspond to the operating conditions existing outside or inside the house. The article “” may also be useful.

One of the popular wall materials used for the construction of private houses is aerated concrete. But despite its fame, very often at the stage of finishing an already built house, fatal mistakes are made, due to which the natural microclimate is disrupted aerated concrete house. And before you start detailed description process of facade treatment, you need to understand why such misconceptions arise, how to avoid them, and what kind of plaster for aerated concrete façade should be.

A little about aerated concrete

To understand finishing issues, let's move a little away from this topic to understand how important it is to do everything correctly and what affects the cladding technology. To do this, you need to plunge into block production technology. And to briefly summarize its description, special additives are introduced into the finished cement-sand mortar, the result of which is the formation of a porous structure. If we look at the body of gas silicate concrete in more detail, we will notice not only microvoids, but also many channels dotting them, forming an “open” cellular structure, which has a lot of positive properties, such as:

• high heat capacity. It is provided not only by the porous body of the blocks, but also by their precise geometry, which allows the use of a minimal joining seam from a special adhesive composition that does not allow the formation of cold “bridges”;
• noise insulation;
• not susceptible to various fungal formations;
• The “open” structure of concrete creates a unique atmosphere inside the room - it will remain cool in the summer and warm in the cold season. But if you break this natural system vapor permeability, for example, due to improper plastering of aerated concrete walls, then the house will be stuffy, and condensation will begin to accumulate on the walls, which will lead to the appearance of mold.

But the cellular structure of aerated concrete blocks also has certain disadvantages:

• a high degree of water absorption leads to rapid destruction of walls without the possibility of restoration. Therefore, waterproofing is given special attention;
• the structure, consisting of open pores, is very well ventilated, which makes the house quite cold, even despite good system heating;
• The heterogeneity of the body of blocks, even of the highest density, makes them susceptible to mechanical stress, which is imprinted in the form of large chips and potholes.

But is it necessary to plaster aerated concrete blocks or is it necessary to install a more thorough cladding? Of course, the ventilated facade system is ideal option for decorative protection of walls, but if you choose what is best to plaster aerated concrete on the outside and follow the technology, then this finishing method will be no less effective.

When is the best time to plaster gas silicate walls?

Aerated concrete belongs to the family of cellular concrete, so it has some of its general properties, namely shrinkage. This phenomenon is inevitable, and if finishing is done earlier than six months later, then cracking is inevitable.

But as we remember, aerated concrete does not like water, so immediately after erecting the walls, they need to be treated with a deep penetration primer, which reduces water absorption. To be on the safe side, you can cover the walls with polyethylene.

The rest of the plastering is best done in the summer, but if the planned finishing occurs during a colder period of the year, then it can be carried out when the temperature at night does not drop below 0 0 C.

The quality of an erected aerated concrete structure directly depends on the sequence of finishing the interior and exterior of the building. Let's consider possible ways, analyzing their advantages and disadvantages.

Method 1 - parallel plastering inside and outside the house

The production of such finishing is very convenient from a technical point of view and significantly saves time. But if we consider this method from the other side, then it is less preferable, since the quality is lost and the characteristics of the newly built house suffer.

Any technology for plastering aerated concrete walls involves significant evaporation of moisture. Of course, most of it will weather away with the help of natural and artificial ventilation, but the bulk of the moisture will be on the walls. Plastering the outside at the same time will clog it for a certain time, which is undesirable.

Method 2 - when exterior finishing is carried out first

It is more logical to initially finish the walls made of aerated concrete from the outside in order to prevent their destruction under the influence of atmospheric phenomena. But this is not entirely true; if you do this, the vapors will be directed inward, which is extremely undesirable.

But even primed walls that have overwintered will easily give up moisture and all the vapors in the spring, without destroying the structure. But if a house is built near a body of water, then priorities change, and under such circumstances, you first need to protect the walls from the street from exposure to abundant moisture.

Method 3 - when interior finishing is done first

Of the proposed options, this is the best, because the volume of moisture formed during finishing will freely come out through the unclogged pores of aerated concrete. After the plaster has completely dried, you can safely begin cladding the facade.

Treating the walls with a deep primer using this finishing method will not interfere with the removal of excess moisture.

Which mixture is preferable as facade plaster?

The building materials market is abundant huge assortment plaster mixtures intended directly for processing aerated concrete. If you believe the manufacturers, then they are all the best in their field. But this is far from true. The characteristics of the main groups of plaster compositions summarized in the table will help you decide.

Type of plaster	Advantages	Flaws
Silicone mixtures based on silicon-organic polymers	resistance to water absorption; does not deteriorate under the influence of precipitation; high level vapor permeability; easy to apply	high cost
Silicate plaster based on liquid adhesive glass	hydrophobicity; low water absorption	not aesthetic appearance after dust settles; limited choice of colors
Acrylic mixture	high strength; good decorative qualities	flammability; low vapor permeability. But this can be corrected by using enhanced protection against moisture and organizing a powerful ventilation system for the room.
Mineral plaster: lime-sand; cement-sand	resistance to temperature changes; good adhesion; resistance to cracking; vapor permeability; low cost	does not have high decorative qualities

All vapor-permeable plaster, except mineral, is produced in the form of a ready-made mixture. In this regard, studying the characteristics various types pay attention to the setting time. The longer it is, the easier it will be for beginners to apply the mixture.

But still, preparing ordinary cement plaster composition much more profitable from an economic point of view. Therefore, all inexperienced builders are tormented by the question: “is it possible to plaster aerated concrete with cement mortar?” The answer is clear - no, for the following reasons:

• low adhesion to gas silicate surface;
• high humidity, which is detrimental to such cellular walls;
• low coefficient of vapor permeability, which will not allow moisture to escape.

Some craftsmen even manage to mix concrete mortar with the plaster mixture in pursuit of profit. But instead they get a bunch of problems and the need for large amounts of money to correct the consequences.

Independent finishing of the facade with plaster

There is nothing tricky about how to plaster aerated concrete as competently as possible. Then it's a matter of technology. Plastering can be carried out using several technologies:

• thin layer;
• thick-layer.

There is no particular difference between them; the choice is yours, depending on which method will be more convenient for applying the plaster.

Preparation

In both cases, before finishing, you need to prepare the base.

Stage 1. The walls are cleaned from dirt with a stiff brush.

Stage 2. Defects masonry joints are eliminated with an adhesive composition.

Stage 3. If there are potholes in the blocks, they also need to be “patched” with the same masonry adhesive or polyurethane foam.

Stage 4. Beacons are mounted on the nails - profiles along which the alignment will take place.

Stage 5. The base of the walls is primed hydrophobic composition surface with a thickness of 2 - 3 mm.

Stage 6. After it has dried, a composition for 5 mm reinforced fabric is applied.

Stage 7. A reinforcing mesh (fiberglass or metal) is attached to the walls with an overlap of 5 cm. It is better to do this with mortar rather than with self-tapping screws. Since in the first case, the mesh will become one with the wall and, accordingly, will “sit” together with the aerated concrete, preventing the appearance of small cracks in the plaster layer. Using the same principle, they are installed and secured plastic corners. Only after the reinforcing plaster has dried can you continue.

Thick-layer surface plaster

When plastering using this technology, it means applying one layer sufficient to perfectly level the wall - at least 10 mm.

Stage 1. Dilute the plaster mixture in a small amount.

Stage 2. The composition is thrown onto the walls.

Stage 3. The rule is to level the plaster along the beacons.

Stage 4. After plastering the entire surface of the walls, wait until it is completely dry and only then can you paint if desired.

Thin layer surface plaster

Plastering walls using multilayer technology is also not difficult and is more suitable for beginners.

Stage 1. The first layer is applied 3-4 mm over aerated concrete. Only after it has completely dried can you continue.

Stage 2. The applied plaster is considered leveling, so special attention must be paid to evenness. Again we wait for complete drying - about 3-4 days.

Stage 3. The final step is to cover the finishing surface, which can later be rubbed down if necessary.

Stage 4. After the previous application has dried, the walls can be painted.

To increase the service life of the plaster, you need to treat it with a water-repellent solution. It will extend the life of the plastered surface almost twice. The use of such compositions is especially important in areas with high humidity.

As you can see, plastering walls yourself is not that difficult. In the first 10 m2 you will develop your own style of application, after which the process will go much faster.

Plastering walls made of aerated concrete indoors is one of current issues during construction from aerated blocks. The fact is that the material needs to be plastered for a number of reasons, the main of which are the cleanliness and smoothness of the surface, since without additional measures the finishing layer will not adhere well. To make it clearer, all these nuances should be understood in detail.

Aerated concrete blocks are characterized by ease of use: the material is warm and light. This facilitates their trouble-free cutting to obtain the required sizes. However, a completely logical question may arise: why is aerated concrete plaster needed? The fact is that the blocks have a smooth surface, which will not allow the finishing layer to be properly fixed. In this case, the choice of plaster mixtures for aerated concrete blocks should be approached with particular care. Plastering walls from the inside allows you to solve the following problems:

• protects the surface from sudden temperature changes;
• provides good level adhesion to other materials;
• improves thermal insulation characteristics;
• provides vapor permeability;
• protects against dampness.

It is worth considering that aerated concrete, like foam concrete, has a cellular structure. Therefore, plastering must be carried out in compliance with technology. Otherwise, air circulation is disrupted, which leads to a deterioration in the properties of the material. Plastering aerated concrete walls outside the room is also necessary. External finishing protects against the effects of precipitation and the accumulation of harmful gases and dust.

When to plaster?

Due to its porous structure, the gas block easily absorbs moisture, so it must be immediately protected from such negative impact. If the building material gets wet, there is nothing critical about it. However, you should not allow the water in the block to freeze. As a result, cracks may simply appear, the strength will decrease, and there is no need to rush with the cladding. After completion of the masonry, the walls must dry. That's why aerated concrete walls It is necessary to plaster only in warm conditions. If the blocks are not laid on a special adhesive mixture, which ensures a thin joint, the drying time increases.

There are situations when during the warm season it is not possible to carry out finishing work. In this case, the walls are covered with deep penetration soil, which will reduce moisture absorption. In addition, it is recommended to cover the walls with plastic film. If you follow the advice of the experts, then it is best to finish walls made of aerated concrete during a period when the temperature at night does not fall below 0˚C. Depending on the region, such temperature indicators correspond to the time from late March to early October. From what has been described, we can conclude whether it is necessary to plaster aerated concrete walls.

Types of plaster mixtures

Before you figure out how to plaster walls made of aerated concrete, you need to decide on the materials that are suitable for these purposes. Construction mixtures can be purchased ready-made or mixed yourself immediately before application. To prepare a high-quality solution, it is necessary to use a filler, which includes sand, gravel, sawdust or stone chips and a binder ( slaked lime, clay, gypsum, cement). Water is added to these components. Cement-sand plaster and mixtures containing slaked lime, cement and sand are prepared using construction site. Today, clay is used quite rarely.

As for ready-made mixtures for plastering, they are supplied in bags in dry form. They include:

• cement;
• gypsum;
• sand;
• fillers.

Such mixtures are divided into cement and gypsum, which have their own properties and application features. Cement-based compositions have a longer drying period and are subject to cracking and settling. Plaster on aerated concrete is applied in a layer 5-10 mm thick.

Which mixture should you choose?

All the mixtures that were listed above have different properties and, when applied to a building material, have different effects. But the question of which plaster is best for plastering aerated concrete walls remains open. First, let's look at what is used to protect external walls, which are constantly exposed to precipitation, wind and temperature. As a rule, these are solutions based on cement and sand. They have proven themselves to be excellent in constant contact with moisture. But the question is: can they be used for plastering aerated concrete? Due to the porous structure, the gas block quickly absorbs moisture, as a result of which the cement simply does not have time to gain the necessary strength.

To plaster aerated concrete walls with cement mortar, you need to do it correctly, i.e. in compliance with technology. To prevent moisture from the building mixture from being absorbed into the block, the surface must be prepared. For these purposes, it is coated with several layers of deep penetration primer, and each layer must dry completely before applying the next. Before applying the plaster, the surface of the wall is wetted. To avoid cracking, it is recommended to use mesh.

How to plaster aerated concrete inside a house? Gypsum mortars, unlike cement mortars, dry faster and the surface is less susceptible to cracking. Mixtures based on gypsum are used for partitions and internal walls, since such compositions are of little use for external use due to permanent influence moisture. Ready-made plaster mixtures contain various additives and fillers, due to which the surface is endowed with resistance to cracking and negative influences.

If you have a choice between a ready-made mixture and one prepared before use, then you should take into account that the properties of dry plaster are more predictable. During the production of such compositions, the moisture content of the sand, the quality of the cement, and the accuracy of all components are controlled. As for mixtures that are prepared on site, checking the quality of cement is quite problematic, if not completely impossible. The main disadvantage of dry plasters is their high cost.

Preparatory activities

To fully answer the question of how to properly plaster an aerated concrete surface, you should start with the tools that you will need for the job. In fact, the tools used are the same as for applying traditional plaster mixture. To prepare the solution, you will need a container, which can be a plastic bucket or tank. They should be sufficient in volume to mix all the components.

After pouring the dry mixture into the container, add water. To mix the solution, use a construction mixer or a drill with an attachment. To achieve the required consistency, determine the proportions of water and material according to the inscriptions on bags of dry plaster. To work you will need the following tools:

• trowel;
• plaster ladle;
• trowel.

Plastered aerated concrete is floated, and the excess solution is removed with a float. Beacons are used to level the surface, and the solution is tightened using a rule. A mandatory tool used to check defects on the surface of walls is a long strip from floor to ceiling. The maximum deviation should be no more than 7 mm.

Plastering the surface from the inside

After deciding how to plaster aerated concrete, they proceed directly to the work process. As with any other type of finish, you first need to prepare the surface. Gas blocks need to be cleaned of residues masonry mixture and seal the seams. As already noted, a primer is applied before plastering. Internal plastering of aerated concrete walls consists of the following stages:

1. Fastening the reinforcing mesh. To increase the strength of the rough finish, you can use a chain-link mesh with a small mesh size. In addition, reinforcing material with alkali-resistant fiber is added to the mixture. The mesh is attached using nails 120 mm long, which are driven well into the aerated concrete wall.
2. If the reinforcement process is not intended, special grooves need to be made for better adhesion of the block surface to the finishing materials. For these purposes, use any suitable tool, such as a hacksaw.
3. Applying plaster mixture to a reinforced base. In this case, they resort to applying the mixture by spraying, when the voids of aerated concrete are completely filled. The first layer of plaster is not leveled, which will provide better adhesion.

A primer must be applied over the rough layer of plaster. It is recommended to add slag sand to the priming solution. It is advisable to apply the finishing layer of plaster using building mixtures with fine sand in a composition that allows you to obtain a smoother surface. At the end of the process, the already dried solution is smoothed to make the surface as smooth as possible. As a rule, smoothing begins 24 hours after application. To make the surface smoother, the blocks are sprayed with water.

The final stage is painting work, which involve the use of paints. In this case, materials are selected with a high degree of vapor permeability. After the surface is painted, it is recommended to apply a water repellent, which will increase the durability and strength of the finishing layer. The service life of interior decoration depends on many factors. One of the main ones is the quality of the materials used, i.e. You should be guided by cost. The characteristics of the aerated block are no less important, because on the surface low quality even a good finishing mixture will not adhere well.

Plastering walls outside

The most inexpensive and common plaster for exterior work is cement-sand plaster. However, the mixture is not suitable for aerated concrete due to low vapor permeability. For these purposes, mineral, silicate or silicone are used. facade plasters. They have a number of necessary characteristics: vapor permeability identical to aerated concrete, good adhesion, and have a beautiful appearance. They begin plastering the facade only after all processes that result in the release of moisture inside the room have been completed and the surfaces have completely dried. Aerated blocks must be dry, and the maximum permissible humidity is 27%. If this indicator is too high, water vapor that will escape will cause peeling of the finishing layer. Facade plaster for aerated concrete must have the following qualities:

• frost resistance;
• high adhesion to the base;
• increased compressive strength;
• weather resistance;
• decorativeness.

Plaster for exterior finishing can be applied to the walls of the house in a thick layer (thick layer) or thin layer (thin layer). Thin-layer plaster is characterized by the fact that the material is applied in several layers no more than 10 mm thick. After preparing the surface and covering with primer, a thin layer of plaster (up to 5 mm) is applied and reinforced with mesh.

For reinforcement, use metal (wire diameter - 0.1 mm, cell size - 0.16 * 0.16 mm) or fiberglass mesh (cell size - 50 * 50 mm). Its installation is carried out with an overlap of 50 mm. In addition, the corners of the building are formed, for which a perforated corner with a mesh is used, which prevents the appearance of cracks due to shrinkage of the building. Using a spatula, the mesh is embedded in the applied mixture. Reinforcing material must be installed at the locations of doors and windows. Then plaster layer level and wait for it to dry. The second layer is considered leveling, so you should strive to create as smooth a surface as possible. Afterwards the finishing layer is applied and the surface is rubbed with subsequent grout. All that remains is to paint the outside of the building, apply textured plaster and water repellent.

Plastering aerated concrete walls inside a residential building is one of the best options preserve the heat-saving properties of enclosing structures.

The use of aerated concrete blocks as a building material is an almost ideal option for low-rise housing. Private houses built from them have such advantages as light weight (and, therefore, do not require the construction of very strong foundations), low thermal conductivity and an affordable price. At the same time, an increase in the humidity of the blocks leads to a deterioration in its heat-saving characteristics and to heavier structures. To protect the walls, plastering of aerated concrete walls is required - sometimes external, but most often internal.

Finishing features

When performing internal plastering of aerated concrete, it is worth taking into account the characteristics of this material and the differences from more traditional brick, concrete and stone. First of all, this concerns the cellular structure of the blocks, which were initially considered insulation, and only then began to be used to build the walls themselves. Due to the open structure, which is the result of adding a special gas-forming agent (aluminum powder) to its composition, aerated concrete has a high level of vapor permeability. This characteristic is one of the main ones when choosing a material and finishing method.

Regardless of the choice of how to plaster aerated concrete, finishing work should begin from the inside, and only then work on the facade of the building. Changing the order and performing the exterior finishing first and only then the interior decoration results in too high humidity in the room. Outgoing (especially when severe frost) steam condenses in the walls at the border between aerated concrete and finishing. The moisture created in this case can lead to cracks in the plaster and pieces of it falling off. That is why interior finishing work is carried out first.

Selection of method and material

When performing finishing work, plastering walls made of aerated concrete is carried out in one of two main ways. The meaning of the first is not only to preserve, but even to increase the vapor permeability of the blocks. The second, on the contrary, involves complete vapor barrier. The advantages of maintaining vapor permeability are the creation of an optimal microclimate, and the option with wall insulation - the preservation of exterior finishing, which is not affected by steam escaping from the building.

Unsuccessful options

It is not recommended to use cement mortar for plastering aerated concrete inside. The first reason is that smooth blocks do not allow the material to stick. The cement layer quickly falls off, and the finishing has to be done again. Secondly, the best option for plastering blocks, a material with the same or greater vapor permeability compared to aerated concrete is considered. For cement, this characteristic is much lower, which does not allow maintaining normal conditions inside the building. For the same reason, the answer to the question whether it is possible to plaster polystyrene foam or polystyrene foam will be negative.

Besides, cement-sand mortar has high humidity due to the significant amount of water required for its preparation. Aerated concrete structures, which have a high water absorption rate, absorb liquid from the finishing material. The quality of the mortar, which requires uniform drying to gain strength, is reduced, as is its ability to adhere to the walls. As a result, cracks appear on the plaster, and its quality decreases, bringing the next repair closer.

You should not choose a special adhesive mixture for finishing the inside of aerated concrete. Despite the fact that it is designed taking into account the characteristics of the material, it is advisable to apply the adhesive in a thin layer, which is not suitable for protection against cracks. As soon as the vapor permeability of the block is broken, on the surface of thin-layer plaster for aerated concrete glue mixture will appear immediately;

• cracks;
• marks from seams;
• and even mold.

Vapor-permeable finish

When choosing the option of finishing walls made of aerated concrete indoors while maintaining the natural vapor permeability of the material, use plaster mixtures with gypsum and gypsum putty. Thanks to the slaked lime and perlite sand they contain, water vapor easily penetrates through the plaster layer. Another advantage of this option is that there is no need to prime the surface of the enclosing structures.

Slightly less often used as interior plaster walls made of aerated concrete such mixtures, which contain a high content of such natural materials with a high degree of vapor permeability:

• chalk;
• marble;
• dolomite;
• limestone.

Their vapor permeability indicators are higher compared not only with internal, but even with external plaster, and the dried solution is easily rubbed, acquiring perfect whiteness. The resulting coating has excellent durability and allows for further finishing.

You should know: Due to the porous structure of concrete, it is recommended to putty it only after applying a primer. If this is not done, cracks will appear on the putty.

Finishing with vapor barrier

When choosing aerated concrete finishing indoors with the elimination of vapor permeability, that is, with complete insulation of the enclosing structures, one of the materials is polyethylene film. The easiest and fastest method of fixing it to the walls is to lay it under one of the finishing layers. However, the speed and ease of installation do not matter if condensation forms on structures finished in this way and the plaster swells. More suitable option in order to plaster aerated concrete inside the house, it will be sand-cement mixture, which contains no additives in the form dolomite flour or lime. With its help, vapor permeability is reduced several times, but the possibility of peeling off the plaster after some time increases.

The following will help to further reduce the vapor barrier without affecting the quality of the finish too much:

• oil paint used to cover walls final stage works;
• applying 3–4 layers of a special composition as a primer for aerated concrete;
• use of adhesives before applying plaster. In this case, you can even do without using putty. Adhesive materials have the same properties and, in fact, replace it.

Features of work

To finish aerated concrete with your own hands, you need to use the same tools that are needed for regular plastering. To prepare a solution of the plaster mixture, you need a special container - such as plastic tank or a bucket made of the same material. Their size should be sufficient to place all the ingredients for plaster inside.

Water is added to the dry mixture that is poured into the tank. The mixture is stirred to the desired state using a drill with an attachment or construction mixer. As a rule, the proportions of material and liquid can be determined by the inscriptions on packages of building materials.

Plaster of aerated concrete walls is applied indoors by “throwing” it using such tools as:

• trowel;
• plaster ladle;
• trowel.

The surface is rubbed with a float. And excess mortar can be removed from the wall with a scourer. Leveling the wall is required with the help of beacons, and tightening the plaster mortar is a rule. Another tool that you can’t do without when performing work is a lath that extends from the floor to the ceiling. With its help, defects on the walls are checked - deviations of no more than 6–7 mm in size are considered acceptable.

Plastering process

Having decided the question of how to plaster walls made of aerated concrete, they proceed directly to the work. They begin, like all surface finishing methods, with preparing the base. The blocks are cleaned of any remaining mixture and the seams between them are sealed. Before plastering aerated concrete indoors, a layer is applied to the porous surface.

Solutions for aerated concrete blocks, which require maintaining vapor permeability, also
are capable of transmitting steam, distinguished not only by high water-repellent properties, but also by the ability to strengthen enclosing structures. The primer must be applied not in one layer, but in several. In this case, it is necessary to take into account that the new application is carried out only on top of the completely dried old one.

1. Fastening the mesh to reinforce the blocks. Because of large size Each aerated concrete product has a small adhesion to finishing materials. And to increase strength, reinforcement is used with a material that contains alkali-resistant fiber. You can use chain-link mesh with a small mesh size for aerated concrete blocks. To fasten it, the use of 120 mm nails is required, which are driven well into aerated concrete;
2. If reinforcement is not used (it is necessary to decide whether a mesh is needed when plastering aerated concrete at the stage of selecting materials), adhesion of the finishing layers to aerated concrete is ensured by grooves intersecting each other, made by any suitable tools- for example, with a hacksaw.
3. Applying the first layer of material (pre-selected, the better to plaster aerated concrete) onto the mesh. In this case, the “spraying” technology is used, which ensures complete filling of the aerated concrete cells, and leveling of the first layer is not carried out, which improves adhesion to the next layer of plaster.

When applying a priming solution over rough aerated concrete plaster, it is necessary to maintain the layer thickness at 4–5 mm. It is recommended to add slag sand to the primer. When applying the finishing plaster layer, it is advisable to use a building material that contains fine sand, which increases the smoothness of the blocks.

Interior renovation is carried out in several stages. When conducting repair work it is important not to forget about plastering concrete walls with inside. Plaster for aerated concrete plays important role, even if we're talking about on work in panel buildings modern layout. As a rule, concrete slabs have an uneven surface, and this defect cannot be corrected with putty alone. Block covering is necessary for a number of reasons. These include the smoothness and cleanliness of the wall surface.

Methods

For plastering the internal surfaces of a building in the construction of which aerated concrete was used, two methods are used. The first method is that plastering on aerated concrete is carried out in such a way as to achieve vapor permeability in concrete walls due to unique qualities material. Builders do not recommend using cement and sand mortar for finishing blocks indoors. Aerated concrete blocks instantly absorb liquid, after which they become covered with cracks. It will not be easy to disguise the emerging irregularities even after priming the vapor-permeable wall.

Some experts plaster aerated concrete blocks using another method - vapor barrier. In this case, the indoor microclimate will be the same as in reinforced concrete buildings. The only difference is that such plastering will be more reliable.

Promotes vapor permeability of walls

The components contained in aerated concrete contribute to the vapor permeability of the building material. However, this factor requires the selection of a certain composition of mixtures for carrying out repair and finishing work on the walls of the building. To do this, it is necessary to carry out plastering in such a way that the inner wall is vapor permeable or, on the contrary, vapor barrier. In a house with such a wall, the microclimate will self-regulate. In addition, there will be no .

Vapor barrier

To process interior wall and increase the vapor barrier at least ten times, experts apply a solution, the thickness of which should reach two and a half centimeters. Plaster contains cement and other ingredients. Sometimes, for this purpose, workers place a polyethylene film under a layer of plaster. But experienced builders do not recommend carrying out such work, since the film can peel off from the plasters and walls due to condensation.

What materials and tools are used?

Everything depends primarily on the task that customers and specialists have set for themselves. To implement it, building materials are selected that can interact correctly with aerated concrete and have the property of vapor permeability. Professionals recommend processing internal surfaces walls made of blocks mixed with gypsum, sand and lime. Builders also use products that contain chalk or marble.

For finishing work, specialists use plastering tools. The mixture is prepared in a container of appropriate size. The solution is mixed using a mixer or. Thin-layer plaster on aerated concrete is applied to the blocks with a trowel or trowel. Rubbing of surfaces is carried out using a grater. The polisher is used to remove excess mixture. The surface of the blocks inside the walls is leveled with beacons. The aerated concrete plaster is pulled together between the guides. Builders determine the quality of the work performed using a lath.