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How is aerated concrete walls plastered indoors? External or internal plastering of walls made of aerated concrete with your own hands: technology for plastering gas silicate blocks and advice from professionals How to plaster walls made of gas silicate yourself

Aerated concrete is a popular construction material, from which strong, durable, warm and resistant to different negative impacts buildings. He has reasonable cost, and construction with its help can be done with your own hands, 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 the 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 conducting 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 feature of absorbing 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 has a low adhesion rate 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 product on the market glue mixture, intended 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 will not be possible to make an optimal protective coating from it, 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, perfect formation is guaranteed smooth surface;
• 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, a sufficiently large amount of water is required;
• 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 It 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, equal to the vapor permeability of the building material itself;
• 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 viability of the solution, and this factor is most important for people who independently carry out the process of applying plaster, and at the same time do not have experience working with such solutions.

Important! For each buyer, an 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 warm time of the year. 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 will certainly be coated with a special primer, and it is important to choose the product deep penetration. 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

Using plaster for the interior decoration of a house built from aerated concrete is a simple and straightforward 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 a 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 with 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. During the work, a building level must be used to ensure that the beacons are evenly fixed.
• 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, with the mixture thrown 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 by strictly following the basic rules and observing correct sequence 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 purchase costs 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 the sequential steps. 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.

Aerated concrete has long been loved by private developers for its excellent performance characteristics and very attractive cost. However, before you start building 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 finishing, it is important to know what can be used to plaster aerated concrete inside a house, and what materials are prohibited. What causes such restrictions and what finishing is ideal for gas silicate blocks will be discussed below.

Features of finishing aerated concrete walls

Before you dive headfirst into the question finishing walls, you first need to understand the structure of aerated blocks, which will completely determine the quality of your future home.

The main way to obtain this cellular material is to introduce special additives into the concrete solution, which, when reacting, form air bubbles that tend to escape. They simply dot the aerated concrete body not only with voids, but also with thin channels, forming a surface reminiscent of natural pumice in its texture. This structure has excellent positive properties with correct final processing of blocks:

• high sound absorption coefficient;
• good level of thermal insulation;
• “breathable” walls create a unique indoor microclimate that retains warmth in winter period years and coolness even in the most extreme heat;
• the porous structure of aerated concrete is not susceptible to the formation and maintenance of colonies of fungal and other microorganisms, which, as a result of their vital activity, destroy walls.

Porous structure of aerated concrete

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 can lead to rapid destruction of the blocks;
• products that have the highest density, and therefore strength, are not resistant to mechanical stress, leading to chipping and cracks;
• the heterogeneous structure, which 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 require mandatory finishing. But it needs to 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, which has been discussed so much, has one more property - good vapor permeability, which is the key to the durability of any structure made of cellular concrete.

In the process of life, people release large amounts of all kinds of moisture into the atmosphere. Just imagine how the air is saturated with it when ironing, washing, drying clothes, cooking or taking a bath. Of course, part of the generated vapors is removed using artificial and natural ventilation, but the main volume is on the walls. In its pure form without finishing, aerated concrete perfectly allows moisture to pass through without retaining it inside its body.

It’s another matter if there is façade and interior cladding, but it is required for such wall material. Therefore, both finishing options should complement each other, maximizing the natural removal of moisture.

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

Ventilated facade is the best type of exterior finishing for aerated concrete walls

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 efficiently and does not interfere with the removal of moisture. As in the previous example, the circulation of steam is not disturbed, and the wall remains dry, so you can choose any plaster mixture.

How to Maintain Natural Humidity Balance

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

Consequence of violation of vapor permeability of aerated concrete walls

Such a serious defect can only be corrected by using materials for interior decoration whose ability to transmit vapors is much lower than that of aerated concrete. This method of screening will prevent moisture from accumulating inside the walls. Best to use:

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

But in this case, the importance of the device increases significantly high-quality ventilation so that 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 would be best to carry out the interior finishing initially. After all, repairs involve a large volume of evaporated moisture, which simply needs to come out, and it is best if it does this through “bare” gas silicate walls.

And one more small nuance regarding the timing of processing walls made of aerated concrete blocks. Any cellular materials shrink well, 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 no less than six months after the complete construction of the building frame and roof installation. It is best to plan this stage of construction for the spring - summer period. As mentioned above, the interior finishing is carried out first, after all processes are completed, after a month you can begin processing the facade.

Which 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 - rapid drying, cracking and crumbling. If we go the opposite way and over-saturated 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. When using them, the main thing is not to overdo it and not to oversaturate the wall surface with moisture. Therefore, before use, read the instructions and follow them strictly;
• special mixtures intended for plastering 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. The only way to avoid mistakes in this matter is to follow the instructions for use from the manufacturer.

But that's not all. The cellular surface does not have good adhesive properties. For this reason, you must initially apply a rough layer of plaster with a thickness of at least 5 mm. But even this finishing option is susceptible to cracking and peeling. To prevent this, a plaster mesh is used. It is best to choose fiberglass or polyurethane fabric due to their excellent alkaline resistance and long service life. Only after applying such a reinforced plaster layer and its complete drying can you safely proceed to finishing.

The best plaster mixtures

Having understood a little about what parameters the finishing mixture should meet, let's look at its most popular and effective types:

• plastering compositions based on silicates, namely “ liquid glass" They combine perfectly with aerated concrete surfaces, especially in terms of vapor permeability. But there is a small “but”. Such plaster mixtures incompatible with many types of finishing, 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 finishing material is suitable for them;
• cement-lime based plaster mixtures with the addition of optimizing additives. Such compositions were invented specifically for finishing cellular material, even without prior priming. Internal plaster of walls made of aerated concrete of this type has not only excellent adhesive properties, but also applicable for both rough and finishing.

The use of such plaster compositions is ideal for gas silicate walls and, if desired, you can use them to apply a leveling layer yourself. Like all specialized materials improved for use in one area, such mixtures have a very high cost, which ultimately adds up to a decent amount.

But there is an alternative that will allow you to economically resolve the issue of carrying out internal plastering - the use of conventional cement-sand mortar in a ratio of 1:5. But you need to use it in relation to aerated concrete surfaces with extreme caution and not to overdo it with adding water to the working mixture.

Do-it-yourself interior plastering process

Even if you decide that the plastering of aerated concrete walls indoors will be done by craftsmen, it won’t hurt to know the process of doing it. After all, even professionals can sometimes make mistakes, and outside control will help 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. To do this you will need:

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

Stage 1. Carefully inspect the walls for construction “jambs”. For example, cracks and chips must be putty and leveled using general level walls For these purposes regular will do repair solution, however, if not much of it is needed, then it is best to use glue specifically designed for aerated concrete.

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

Step 3: Apply one coat of primer. This can be done in a way convenient for you, for example, using a roller or brush. To reduce the consumption of primer solution, experienced builders will use conventional sprayers. If you don’t have any at hand, then you can just as easily use an old model of a vacuum cleaner, the principle of which is to blow air. Only after the first layer has dried thoroughly can you begin to apply the second.

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

Stage 5. Starting from the bottom, pour 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 plaster and press down until it rests securely on the wall. Now you can use a notched trowel to level the adhesive layer so that the direction of the grooves runs horizontally. This improves adhesion both to the wall and to future plaster.

Applying plaster

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

Stage 1. Wielding building level, profiles are set - beacons.

Stage 2. Mix the working solution 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 mixed to a thick consistency.

Leveling the solution according to the beacons

Stage 3. Between the two beacons, mortar is poured along the entire height of the wall. Using the rule, the resulting layer is leveled to the required level of smoothness. Apply the rule to the wall again and check if there are gaps between them. If there is any, add mortar and level it, but no, great, plaster all the walls in a similar way.

The described plastering technology is quite simple and even an inexperienced craftsman can successfully use it. The main thing is to choose the right material to plaster the aerated concrete walls inside the house.

Low-rise construction using gas silicate blocks has become widespread in all climatic zones of our country. Unique properties materials, which we will discuss in detail below, allow the construction of aerated concrete structures in hot regions and in places where negative temperatures prevail. However, implement directly construction works- only half the battle. The comfort of further living in the house, its durability and preservation of operational characteristics depend on the competent finishing of the facade and the inner surface of the walls. One of the main stages is plastering aerated concrete walls indoors. Let's take a closer look at the technology of the finishing process and the nuances that affect the quality of the final result.

Features of plaster on aerated concrete

To figure out what, when and how to properly plaster aerated concrete, you need to study the properties of the building material itself. The peculiarities of plastering walls are associated precisely with the unique characteristics of gas silicate blocks.

Initially, aerated concrete was developed as a material that was used to insulate buildings. Therefore, research was carried out in the direction of creating a porous structure, which, as is known, provides maximum thermal insulation.

As a result, two varieties emerged:

• foam concrete, the porosity of which is achieved by forced mechanical foaming;
• aerated concrete, in which gas bubbles are formed by adding aluminum chips that react with the main composition (hence the name of the material).

During the process of creating blocks, gas bubbles tend to the surface, making their way through the thickness of the mixture. Therefore, the cells in the structure of aerated concrete are not isolated, but represent a unique system of interconnected channels. This is due to main feature material, thanks to which the finishing technology for gas silicate differs significantly from other building materials. This difference is vapor permeability. Aerated concrete perfectly conducts saturated water vapor through its structure. At the same time, it has increased hygroscopicity, that is, it is able to quickly absorb moisture and retain it inside for a long time.

Based on the foregoing, the fundamental principle for plastering walls made of aerated concrete looks like this: water vapor should be able to be easily removed from the thickness of the walls or should not penetrate inside at all. Failure to comply with this approach is fraught with the appearance of serious problems in the cold season: at subzero temperatures, the moisture inside the blocks will freeze, and the material will simply “tear”: cracks will appear, shedding will begin, and not only the appearance, but also the thermal insulation characteristics. To prevent this from happening, it is necessary A complex approach to the choice of options for external and internal finishing of the building.

We immediately answer the question: is it necessary to carry out external work? Definitely yes, because:

• the impact of environmental factors on the porous structure of the material will lead to accelerated erosion;
• the above-mentioned structure, consisting of almost end-to-end microchannels, makes the material sufficiently blown by air currents, which creates discomfort when living in a house in cold, windy weather;
• insufficient mechanical strength open material makes it vulnerable to accidental blows and other force impacts;
• a finished wall definitely has aesthetic advantages over untreated masonry.

Dependence of internal plaster on facade finishing

To clearly demonstrate the reasons for the need to select a material for interior work in accordance with the design option for the external surface of the walls, let’s consider the main characteristics of various types of aerated concrete. For ease of perception, we will create a summary table of parameters:

From the given data it is clear that even the densest and most durable brand of aerated concrete has high rate energy saving (the value of the thermal conductivity coefficient of 0.15 was compared with that of natural wood, traditionally considered the standard warm materials). At the same time, vapor permeability remains at a significant level for all brands of gas silicate.

During human life, moisture is constantly released into the air in interior spaces. In addition to the normal breathing of the inhabitants of the house, there are household processes, including washing and drying clothes, washing dishes, and high humidity in sanitary facilities is their integral property. As mentioned above, excess moisture must either be easily removed through gas silicate walls, or not reach the surface of the material at all.

If special vapor-permeable plaster is used for exterior work, then a similar composition must be used inside. As a result, the overall vapor conductivity will remain virtually unchanged compared to the original characteristics of aerated concrete, and the aesthetic appeal and wear resistance of the structure will increase significantly.

Ventilated facades

An alternative option for exterior finishing, in which vapor-permeable plaster is also used for interior work, is the creation of ventilated facades. This technique involves installing a ventilation gap between the wall surface and the layer of finishing material. The most common examples of such options are siding or brickwork finishing. The creation of ventilated facades provides for the possibility of additional external insulation of walls, however, it is also necessary to use materials with appropriate vapor permeability: mineral wool is quite acceptable, while foam plastic and extruded polystyrene boards are categorically unacceptable.

Other finishing options

Other materials for facade decoration (traditional plaster compositions, adhesive bases for decorative stone, porcelain stoneware, etc.) interfere with the vapor permeability of aerated concrete, so internal work must also ensure maximum vapor barrier. In such cases, it is advisable to use special hydrophobic primers and finishing materials based on sand and cement, and the thickness of the plaster should be significantly greater than for compositions used while maintaining the ability of the walls to transmit water vapor.

With this method of finishing, the room must have a well-thought-out ventilation system. Otherwise, constant humidity will lead to multiple manifestations of fungus and mold.

Materials

The given recommendations help solve the problem of choice budget options interior decoration. Which is better: plaster or drywall? The vapor conductivity coefficient of the densest aerated concrete is 0.16, and the same indicator for gypsum sheets = 0.07, which is more than two times less. Therefore, it is recommended to use plasterboard only in the case of constructing blind vapor barrier external facades; to create a ventilated structure, it is necessary to use plaster mixtures for aerated concrete surfaces inside the house.

With regard to the kitchen, bathroom and toilet in houses made of gas silicate, the question no less often arises: is it possible to lay tiles? The answer is similar: since the vapor conductivity of ceramic products is close to zero, such finishing is permissible with hydrophobic design of the walls on the outside.

How to plaster aerated concrete

Having understood the features of the technology, let’s move on to choosing the finishing material itself. With today's diversity building mixtures It’s not difficult to decide what to plaster with.

Most branded manufacturers of building materials produce compounds for working on aerated concrete. The most popular plasters include AeroStone, Bonolit, Ceresit or Knauf. Vapor-permeable plasters are somewhat more expensive than conventional plasters, so when deciding which one is better, financial side plays not the least role.

Before purchasing, be sure to read the product description and make sure that the mixture you are purchasing is actually intended for use on aerated concrete.

Preparing the walls

So, is it necessary to plaster - we figured it out, with suitable materials We've decided, let's get to work. Gas silicate blocks have standard size and are laid in perfectly even rows, so preliminary leveling of the surface requires minimal effort and time. This is usually done using grout mesh or sandpaper.

The next step is priming for plaster. This procedure cannot be skipped, because otherwise the finishing material will not adhere well to the walls or will quickly crack during use.

Plastering process

Next we move on to the finishing work itself. The technology for plastering aerated concrete walls indoors is not much different from similar work on any wall base and can be easily done with your own hands:

• vertical beacons are installed along the width of the rule;
• Preliminary puttying of the walls without plaster is carried out to secure the fiberglass mesh.

Is a mesh needed?

We will devote a separate section to this aspect. Plaster is a rather fragile coating. Therefore, with the slightest shrinkage of the foundation, cracks may appear on the surface, despite the monolithic reinforcing belts and other strength of the structure. Such phenomena can be avoided by laying a special mesh made of materials resistant to alkaline environments. Strong fibers reinforce the surface and prevent cracking.

Despite the additional acquisition costs, the answer to the question of whether a mesh is needed is clearly affirmative.

If you want the finish to last for a long time, do not start work immediately after construction is completed. The house needs to stand for at least 6 months, and preferably 1 – 1.5 years. This will allow the aerated concrete to achieve optimal moisture levels, and the foundation to undergo final shrinkage.

We continue the plastering process:

• spread a layer of plaster from bottom to top over the area to be treated;
• guided by the beacons, we level the surface;
• dismantle the beacons and seal their attachment points;
• After drying, we finally rub down the walls.

Tools

Scroll necessary tools small:

• sandpaper and grout mesh;
• long profiles for beacons;
• brush or roller for applying primer;
• container for diluting the plaster mixture;
• spatula for application;
• rule for leveling the surface

Putty

If you plan to further paint the aerated concrete, after plastering it is recommended to carry out finishing putty. This will improve the adhesion of the paint to the surface and increase its service life. To carry out the operation, use special compounds for puttying aerated concrete, sold in construction supermarkets.

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 when it comes to carrying out 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 the unique qualities of the 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 may 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.

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. Grinding 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.

Initially, the fate of aerated concrete was prepared good insulation, and he set about his task perfectly. But over time, apparently, the “concrete” nature of this material played a role, and it began to be widely used as the main material in construction, successfully replacing the same brick or stone.

The price of the importance of the material has increased, but the requirements for products that are used in conjunction with it have also increased, the usual cement mixtures and plaster are no longer suitable. Here we need special ones, which the construction industry did not fail to immediately saturate the market with.

General information

When working with aerated concrete, you need to know the nature of its production.

A little about the essence of the problem

In the manufacture of aerated concrete blocks, the same things are used:

• cement,
• quartz sand,
• even ash and slag,
• and also gypsum and lime.

But, which creates advantages for this material and some problems in the future, during finishing, so-called gas-forming agents are added to the composition, which, when reacting with lime, contribute to the release of hydrogen and the formation of pores 1-3 mm in size inside. These pores provide the extraordinary properties of the resulting product. Typically, all kinds of aluminum pastes act as gas generators.

What do we get in the end?

As a result of all physical and molding processes, we obtain a material with simply outstanding properties:

• it is unusually strong, concrete after all;
• it is noticeably lighter than a conventional concrete block of the same volume;
• it, as it turned out, is very easy to process, now it’s not a problem to even get any angles and irregularities in any direction - all this thanks to the pores inside;

• Even nails easily fit into this material;
• it is completely non-flammable;
• Compared to ordinary concrete, “gas” has less so-called natural radioactivity, because crushed stone and natural mica are not used in its production;
• as practice has shown, and which was another additional and unexpected advantage, the material hardens even more over time, increasing the strength of structures created from it;

• but the most important thing, around which all the fuss flares up when finishing aerated concrete - it has excellent heat-insulating properties and
• vapor permeability.

Is it any wonder that more than 250 factories have already been set up around the world to produce this material. In Russia alone there are more than 80 of them, and most of the largest ones were built literally within 2-3 years - from 2009 to 2012.

Ubiquitous standards

Such mass production of aerated concrete has necessitated the creation of new State standards regulating both its release and use.

Here is a list of all documents regulating the use of aerated concrete on the territory of the Russian Federation:

• GOST 25485-89 “Cellular concrete” - classifies all possible types of materials under one common name cellular concrete;
• GOST 21520-89 “Small cellular concrete wall blocks” - determines the procedure for working with blocks;
• SNiP 277-80 “Instructions for the manufacture of products from cellular concrete” - building codes and rules for working with this material;
• GOST 31359-2007 “Autoclave-hardening cellular concrete. Technical specifications" – technical specifications production and use of one of two types of aerated concrete - autoclave, the production of which occurs when high blood pressure in a steam-saturated environment (another type - “non-autoclave” - is produced without pressure or with electrical heating);
• GOST 31360-2007 “Non-reinforced wall products made of autoclaved cellular concrete” - defines the recommended types of buildings made from the described material.

A little physics and its consequences

When it comes to aluminum, hydrogen and a chemical reaction, whether you like it or not, you have to delve into the essence of the emerging processes that tell us that:

• yes we get very good material in terms of vapor permeability;
• but it also requires appropriate discipline when using it, which many violate;
• as a result, visible damage to the surface finished with plaster, which is based on aerated concrete;
• the fact is that it is impossible to cover a material with high vapor permeability with a material that does not allow steam to pass through at all - this leads to the fact that moisture simply will not find a way out and will accumulate inside at the boundary of the layers;
• therefore, it is necessary to follow the scheme of “non-decrease” of the vapor permeability coefficient; in other words, if we assume that this coefficient for aerated concrete is 1.0, then for the next layer it should already be no lower than 1.0, or even higher, say 1.2, then the next one should already be higher than 1.2, and so on .

And this is physics, from which there is no escape, like the law of universal gravitation.

What does disobedience lead to?

Violating physical laws is always unpleasant and it’s not just an apple falling on your head.

In the case of aerated concrete this is:

• periodic cracking of the surface, which is periodic in nature, depending on the time of year and environmental humidity;
• eventually the cracks turn into cracks and the finish simply falls apart;

• in addition, moisture constantly accumulates in the inner layers, resulting in mold and, again, destruction of the masonry;
• in any case, aerated concrete is no longer able to fulfill its original functions on thermal insulation.

There is an exit

As a matter of fact, all these processes did not come as a surprise to builders and special ones were developed:

• adhesives for joining aerated concrete blocks when laying them on top of each other;
• primers for exterior finishing these blocks;

• plasters for both interior and outdoor work.

Now you only need to know about the availability of these finishing materials and use only them with aerated concrete.

Helpful advice! Another conclusion from all the discussions about physics is that when finishing these blocks, we strongly advise you to first finish all the work inside, wait a while until all the finishing has been thoroughly dried, and only after that. And by no means in reverse order.

Work progress

If everything is understood correctly, then the work itself will not present significant difficulties.

The scheme we are striving for

When performing the work, the final result will be the following simple multilayer structure:

• A – aerated concrete block;
• B – reinforcement, you can’t do without it, despite the increased strength of the blocks;

• C is a special adhesive composition for aerated concrete, by no means an ordinary cement mortar;
• D – plaster on a possible primer.

Plastering aerated concrete

All work is done as follows:

• first, thoroughly clean all the seams between the blocks to a depth of 1 to 4 mm; the main thing here is to eliminate any unreliability in the masonry;
• then thoroughly clean everything from dust, including with a damp cloth;
• let the surface dry completely;

• further, everyone can choose the finishing algorithm at their own discretion;
• for example, many people skip the very desirable next stage - priming - and there is no big crime in this in departing from technology; The area of ​​work, as a rule, is quite substantial and it is not a sin to exclude unnecessary work that is not super necessary;

Helpful advice! If you still decide to apply a primer and want to do it quickly, we recommend using a spray gun and spraying the primer. This method, of course, is not distinguished by its economical approach to materials; it does not always give satisfactory uniformity, but you will save a lot of time.

• but the next operation will have to be performed one way or another - the fact is that the aerated concrete itself and the plaster used have good adhesion and are able to hold each other without any problems;
• but we recommend either making notches with a chainsaw on the surface of the wall to improve adhesion, or, best of all,
• place a fine metal or polyethylene mesh over the entire surface area, this will contribute to a much greater effect of holding the plaster;
• and you can fix the mesh with the usual available fasteners, we advise you to choose only those protected from corrosion;

Helpful advice! To prevent the mesh from sagging, it is necessary to accurately select the fastening step of the fasteners. We advise you to choose it within 120-150 mm, as practice shows, this is the most convenient distance.

as soon as the “spray” has set, apply the next layer, no thicker than 5 mm, which is already smoothed out; on this layer, irregularities will be visible that will have to be eliminated by the finishing layer;

we wait until rough plaster completely dry;

as a final touch, we proceed to the finishing layer based on very small components;

When last layer When it is completely dry, it is sanded, first rough sanding with regular sandpaper, and then more thoroughly with a sanding machine.

conclusions

Aerated concrete is an excellent and very popular building material with remarkable properties, which put it forward as one of the most popular. But for these outstanding properties you have to pay for your understanding of all the processes taking place. Hence the use of special plaster and the need to maintain strict discipline when doing it.

Violation of these rules can lead to complete and undeserved disappointment with aerated concrete. Be sure to check it out additional video in this article, it will help you not to relax and will remind you of the nuances on the topic.