How and how to plaster aerated concrete inside the house: we are considering the option of plastering for various surfaces. Features of plastering walls from aerated concrete inside and outside the room Technology of plastering walls from aerated concrete outside

Plastering of aerated concrete surfaces is a necessary measure due to the fact that the porous structure of the material allows moisture to pass through well, and this is unacceptable for the durability of any residential building. Aerated concrete bricks are highly hygroscopic. Therefore, the facade plaster for aerated concrete is applied without fail, preferably in two layers, and with preliminary protection of the walls with a primer and antiseptics.

Any precipitation is a risk of wetting the walls of gas blocks, which, after drying, can begin to collapse, becoming covered with microcracks inside and outside the house. And this risk increases markedly in winter, because the water in aerated concrete when freezing will expand and expand the building material, breaking its monolithic structure.

Before plastering the facade and side walls of the house, especially in winter, the outer surface must be protected from moisture with a polyethylene film. After the obligatory plastering, any decorative material for the external cladding of the facade can be attached to the surface finished with mortar.

Purpose of finishing outside:

Increase of heat and noise insulation of the building and premises;
Minimizing the likelihood of wetting the walls with atmospheric precipitation;
Protection of external surfaces from contrasting outdoor temperatures;
Decorative function.

Plastering is the most common way of decorating facades and walls made of aerated concrete due to its relative cheapness and ease of execution. But even such a simple process requires study, so a small overview of the characteristics of plastering compounds used in construction for outdoor work and methods of plastering aerated concrete surfaces will be useful.

Three types of practical and cheap building materials for wall decoration are common, therefore, than plastering aerated concrete, you should decide after studying all the options:

Cement-sand mortar

This is the most common internal mixture for plaster among builders, but it is not recommended to use it for plastering gas blocks from the outside, since the gas brick does not hold cement well. And, if a primer or fiberglass mesh can be used on the walls inside the house to hold the plaster cement-sand mortar, then these methods are not suitable for working outside due to the constant exposure to temperatures and precipitation. Protect aerated concrete blocks sand mortar undesirable, since gas blocks immediately absorb moisture from the mixture. The reasons for the ban are as follows:
1. The cement-sand mixture has a lower vapor permeability coefficient than aerated concrete. And the most important rule of a plasterer is to use a material that, in terms of the vapor permeability coefficient, is the same as this indicator or greater than that of aerated concrete;
2. It is not recommended to insulate the house with expanded polystyrene or polystyrene for the same reason.
Plaster on cement applied over aerated concrete contains a lot of water, since it is kneaded on it. Aerated concrete is initially produced with a high coefficient of moisture absorption, therefore, moisture from the solution will quickly enter the wall, leveling the adhesion, layer quality and strength of aerated concrete blocks, because the main condition for the strength of concrete is slow setting and hardening;
Cement-sand mortar has low adhesion, that is, adhesion. Therefore, for plastering internal walls, lime can be added to the solution in proportions of 1:10 (lime - cement);
The cement mortar must be covered with a finishing layer of plaster, as the starting layer will be rough.

Construction adhesive mixture

Construction glue is a very expensive solution, and it is impractical and uneconomical to apply it in a large layer instead of plaster;
When plastering aerated concrete blocks with a building glue mortar, the vapor permeability of aerated concrete will decrease, since the glue does not allow air to pass through well. As a result of clogging of the pores in the blocks, the material may begin to crack, mold may appear in poorly dried places, and local peeling of the adhesive plaster may occur.

Gypsum for aerated concrete

Positive sides when plastering with gypsum mortar:

Gypsum plaster mix quickly sets and dries;
Gypsum solution does not shrink;
Even a thin plaster surface will be smooth;
For such plaster, a finishing decorative layer is not needed.

Disadvantages:

The vapor permeability coefficient is poor;
Large water consumption;
Any atmospheric precipitation moistens the gypsum plaster to the entire depth of the layer;
Due to too good adhesion, colored spots may appear on the surface due to the penetration of mineral dyes in the composition of aerated concrete into the gypsum layer.

Gypsum or alabaster is considered the most effective composition for plastering aerated concrete surfaces outside and inside the house. This mixture for finishing facade works has a vapor permeability coefficient, which is the same as that of aerated concrete, excellent adhesion, and an attractive appearance.

What plaster is better to plaster aerated concrete walls?

There are special mixtures for working on aerated concrete. It is preferable to use mixtures with the following properties:

High or medium vapor permeability;
No more than 200 ml of water per 1 kg of the mixture for mixing it;
Minimum and maximum thickness of the plaster layer (the greater the difference, the better);
The indicator of adhesion to the main surface - ≥ 0.5 MPa;
Resistant to low temperatures;
Resistant to cracking;
Long service life of the working solution.

Conditions for plastering aerated concrete surfaces

Plastering in the warm season involves the rainy season, but getting wet aerated concrete blocks is not as critical as freezing moisture inside them. Therefore, it is better to protect a dwelling made of aerated concrete with moisture-proof films at any time of the year, since the walls may simply not have time to dry out in the fall before frost.

The newly erected walls of the house must dry out before plastering them, therefore, both construction and plastering on aerated concrete should be carried out in the summer. Due to the fact that the first row of gas bricks is usually laid on a cement-sand mortar, the drying time of the walls increases, and this circumstance must be taken into account when calculating technological processes.

Applying two or three layers of primer to aerated concrete will significantly reduce its water absorption. The practice of building private housing has shown that the best time for the construction of aerated concrete walls of a building - the season when the temperature at night does not drop below 0 ° C.

There are three options for finishing aerated concrete surfaces, taking into account the priority finishing works:

The first is the exterior finish. Private developers mistakenly think that it is first of all necessary to protect the house from the outside so that the walls do not get wet from rain and snow. But even wet in autumn, but primed aerated concrete will dry quickly in spring at positive temperatures. With the walls covered with plaster, moisture in winter will evaporate only inside the house, which will not only extend the drying time of the walls, but also affect the occurrence of cracks on interior walls at home;
The first is the interior decoration. With such an organization of the process, the moisture accumulated in aerated concrete has an outlet only to the outside, and the possibility of cracking will be minimal. Therefore, this finishing option is considered the most correct;
Exterior and interior decoration is carried out at the same time. This option is the worst of the three. Moisture in gas blocks becomes clogged, and its slow evaporation will lead to cracks, mold, and flaking of the plaster layer.

Internal plastering technology

Before plastering the walls, they must be leveled with a special plane, grinder or float on aerated concrete. Leveling will help to save on the thickness of the plaster layer - if applied too thick, the plaster may begin to crack or even flake off.

Sanded walls should be primed, but it is not recommended to dilute the primer with water. Then, metal beacons are attached to the walls - 2-3 meter perforated ribbed corners, which determine the thickness of the plaster layer. The corners are attached to plaster or alabaster, the distance between them is determined by the width of the rule or the widest spatula. The verticality of the attachment is checked by level.

On the walls for aerated concrete, plaster is applied from bottom to top, and leveled with a rule. Gaps and irregularities are filled with mortar using a smaller spatula. After an hour and a half, when the first layer of the solution has set a little, it is moistened with a spray bottle and leveled with a wide spatula (rubbed over). It is advisable to remove the lighthouses before this operation, since they can serve as a point of occurrence of "cold bridges". The inner corners are leveled and reinforced with the same beacons, the outer corners are reinforced with metal perforated corner no ribbing, and fiberglass mesh. After the last layer has completely dried, the wall must be wiped off.

If the walls inside the premises will be painted, then it is recommended to use paint with good vapor permeability, for example, acrylic, water-based or PVA-based paints, as well as based on organic solvents.

How to plaster aerated concrete inside the house updated: January 23, 2017 by the author: Artyom

The approach to plastering the internal surfaces of aerated concrete walls is somewhat different from similar works on brick and concrete walls.

From this article, you will learn what exactly is worth considering when plastering aerated concrete, how to properly solve the issue of vapor barrier, and which mixture is best to use. There will also be a step-by-step consideration of the sequence of do-it-yourself work, corresponding the right technology aerated concrete plaster and the ratio of the proportions of the solution.

There are two options: to use materials for a vapor-permeable finish, which will not interfere with the initial properties of the gas block, or to use a vapor-barrier finish, which significantly reduces the vapor permeability coefficient of the material.

The first option is good because the vapor permeability of the walls of the house contributes to the fact that the microclimate in the building will constantly self-regulate, as a result of which life in it will be as comfortable as possible, you will not need to worry about dampness, the formation of fungi or mold on the inner surface of the walls.

By artificially reducing vapor permeability, you will lose all this, but you will get a more durable layer of facade plaster at home.

The fact is that it is the steam escaping from the inside of the house through its walls that is the main reason for the cracking of the external plaster coating in the cold season.

This happens due to the "dew point" - when steam, the temperature of which is lower than the air temperature, condenses on the surface of the wall under the layer of external plaster, freezes, and provokes delamination of the cladding.

The choice of the type of plaster mix lies entirely on your shoulders. You should approach it as responsibly as possible, and be fully aware of what exactly you want to receive and what you donate in return.

Reviews of the builders responsible for plastering the walls from the aerated block indicate that most customers prefer the option of a vapor-permeable finish.

1.2 Which plaster is better to use?

As can be understood from the above, there are two types of plaster mixes for performing work on the walls of aerated concrete inside the building - vapor barrier and vapor permeable.

Vapor-permeable plaster mixes include gypsum-based mixes in proportion. The best option with the best price-quality ratio is the Pobedit Aegis TM35 plaster mix, which contains lime.

Aegis TM35 (lime) has all the properties that should be inherent in a high-quality mixture for aerated concrete - minimum weight, high adhesion properties, and strength of the hardened layer.

This mixture is based on gypsum (lime) and perlite sand, it also contains slaked lime, which guarantees the maintenance of optimal vapor barrier characteristics of the walls of the house.

If no additional wall cladding is planned after the plaster layer (painting of the plaster layer is quite common design solution today), then it is worth giving preference to the mixture "Aegis S50", which includes lime.

This material, although it has a slightly lower vapor conductivity, due to the presence of 2.5% concentration of polymer impurities in the composition, guarantees maximum strength and whiteness of the walls, since the mixture is based on lime and gypsum with a fraction size of 60 to 90 μN, which is 30-50 percent less than products in the same price range.

The category of vapor barrier plaster mixes includes materials that include a large number of polymer impurities - this is widely popular in recent times plastic plaster.

This also includes the usual cement-sand plaster, the composition of which does not contain additives in the form of lime, or dolomite flour. To ensure maximum vapor barrier (reduction of steam permeability by 11-12 times), it is required to apply a composition of sand-cement plaster with a thickness of 2-2.5 centimeters. For large areas, a sand plastering station can be used. cement mortar... Since plastering the walls with a cement-sand mortar of a room is not an easy task.

There are more radical inexpensive ways a decrease in the vapor permeability of aerated concrete walls, for example, a lining under a layer of plaster with ordinary polyethylene film, however this way not recommended for use due to the fact that delamination of the finish from the walls may occur due to the formation of condensation on the surface of the film.

The optimal cost option for the vapor barrier plaster of the inner walls of an aerated concrete house is the composition of the usual inexpensive gypsum mixture together with vapor barrier primers such as "Pobedit Grunt-Concentrate" and the like.

To achieve the desired effect, you will have to prime the walls from the aerated block 3-4 times, which will reduce the vapor permeability of plaster 10 millimeters thick by almost 5 times.

It is also worth considering the surface finish of the room, for example, plaster, painted oil paint, loses in steam transfer about 30% per composition, gluing wallpaper, especially fleece, contributes to a similar effect.

2 Required tools and work technology

The composition of the tools by means of which the plastering of the inner surfaces of the walls from the aerated block is performed does not differ in any way from the tools for similar work on other surfaces.

You will need a container in which the plaster mixture will be stirred.- a plastic or metal bucket or tank, the main thing is that the size is suitable. For high-quality stirring, a drill with a mixing nozzle is required, so it is quite difficult to bring the mixture to the desired consistency with your own hands - clots and lumps will form.

The ratio of the proportion and composition of the dry mix and water are indicated by the manufacturer on each package, do not neglect these recommendations, as they may differ for different plasters.

A mixture of plaster is poured onto aerated concrete using a trowel or a special plastering bucket. Leveling and plastering is carried out with a wire and trowel.

If you need to apply a thick layer of plaster, over 1 cm, to the wall, then it is recommended to purchase plaster beacons for plastering, which greatly simplify leveling and plastering with mortar. You can rub the surface with a plaster float or ordinary fine sandpaper.

If the walls are covered with a thick layer of plaster, then it is necessary to use a reinforcing mesh, which will strengthen the finishing layer and prevent it from cracking and peeling.

Also, the mesh improves the adhesion of the solution and the aerated block, as a result, it is much easier to apply the mixture to the wall surface. It is best to use plaster fiberglass meshes with a mesh size of 5 × 5 mm.

Stages of work:

We prepare the surface - we clean the walls from dust, glue residues, and any dirt. Oil stains are degreased with alcohol or gasoline. If the stain cannot be processed, then it is necessary to gouge it out of the aerated block, and the formed unevenness should be repaired with plaster mortar.
The walls are covered with a layer of primer. The number of layers is determined by the technology and requirements for the vapor permeability of the walls, while, to apply the next layer, you must wait until the previous layer is completely dry.
If necessary, a reinforcing mesh is mounted on the walls. The mesh should be installed tightly, without sagging - this is best done using dowels with wide heads.
A rough layer of plaster mixture is applied. The mortar is evenly sprayed on the wall with a trowel, and leveled with a rule.
After setting the rough layer, it is covered with a primer and carefully leveled.
After the rough layer has completely solidified, the wall is plastered with a finishing mixture, which is leveled with a spatula.

After two days after applying the finishing putty, you can start decorative finishing work.

2.1 Analysis of the features of the plaster of aerated concrete walls (video)

Aerated concrete blocks are increasingly used in the field of low-rise construction. That is why the question of how the internal plastering of aerated concrete walls is made is becoming more and more popular.

In this article, we will consider the features of the use of various plaster mixes when decorating low-rise buildings, mainly for residential purposes.

The need for timely wall decoration

Before deciding what is better to plaster the walls of aerated concrete, let's figure out what this material is and what are its characteristics that can affect the finishing work.

Aerated concrete has a low specific gravity, which minimizes the degree of mechanical stress on the foundation. The low weight of the building material is due to the cellular structure of the blocks. And, if low weight is an advantage, then the cellular structure turns into a disadvantage.

The fact is that aerated concrete blocks are characterized by low hydrophobicity. They literally absorb moisture, both from the external environment and from the inside of the building. By absorbing moisture, the blocks lose their original heat-saving qualities. In addition, excess moisture leads to the gradual destruction of building materials and structures erected with its use.

It is for this reason that the plastering of aerated concrete walls should be carried out in a timely manner.

Features of wet plastering of walls from aerated concrete blocks

Plastering of building objects erected with the use of aerated concrete must be carried out both from the outside and from the inside. The finishing process should start from the inside and then move on to the facade cladding.

A gross mistake is the external plastering of aerated concrete walls, carried out in the warm season. In this case, interior decoration begins with the onset of cold weather. Meanwhile, the water used in the manufacture of wet plastering mortars will for the most part seep out both through the ventilation and through the aerated concrete blocks.

As a result, water vapor will condense inside the blocks at their interface with the exterior cladding, as the walls will eventually be covered with plaster on both sides. With a significant decrease in ambient temperatures, the external plaster, due to freezing of moisture in the walls, will crack and flake off.

The technology of plastering walls made of aerated concrete does not provide for the use of cement-sand mortars, since such a coating will ultimately become a serious obstacle to vapor permeability. excess moisture it must find a way out in the walls, otherwise the external plaster will deform over time and become unusable.

There are two ways to solve the problem of removing excess moisture without harming the indoor microclimate:

Through the use of plaster mixes specially designed and manufactured for finishing structures made of aerated concrete.

Speaking of special mixes that do not interfere with the removal of steam, we mean plaster mixes with a high gypsum content.

Today, in any hardware store you can purchase a wide range of gypsum putties, both for outdoor and indoor use. The composition of high-quality modern putties, in addition to gypsum, includes slaked lime and fine-grained perlite sand. Due to such components, the mixtures are characterized by a high degree of adhesion, and therefore it is not necessary to prime the surface of the walls before finishing work.

The finished plaster layer of the putty performs the function of a filtering material, due to which water vapor is effectively removed outside, while moisture practically does not enter the walls from the outside.

Using a vapor barrier film installed from inside the room.

Vapor barrier material - penofol

The film applied to the wall before applying wet plaster prevents moisture from penetrating into the blocks, therefore the type exterior decoration not fundamentally important.

At first, the plastering of the walls inside the room was carried out using ordinary plastic wrap. As it turned out, the use of such a vapor barrier is not the best solution, since there is a high probability of condensation accumulation and swelling of the plaster. The solution to the problem is the use of micro-perforated polyethylene nonwoven webs.

When using a moisture barrier, it is allowed to use cement-sand plaster mixtures made without the use of dolomite flour or lime as fillers.

The choice of tools for finishing work

Before plastering aerated concrete walls, you need to decide on the choice of tools.

In principle, the tools will be required the same as when carrying out conventional plastering:

a plastic container for stirring a solution with a volume of at least 10 liters;
rotary hammer with speed control and special mixing attachment;
plastering rule;
spatulas of different widths (wide 50 cm and narrow 10-15 cm);
medium sized trowel or plastering bucket;
water level;
graters for leveling and grinding.

Gypsum putty application technology

Modern technology for plastering walls made of aerated concrete inside and outside using gypsum putties is as follows:

Preparing the surface. To do this, we thoroughly clean the walls from dirt and dust.

To increase the adhesion of the putty to the surface, we use an acrylic primer, which can be applied with a wide brush or roller. At the same stage, we install beacons. Of course, you can work without beacons, but with special guides, the finishing will be carried out faster and better.

If the wall does not have significant irregularities, we choose the thinnest beacons to reduce the consumption of putty. Installation of lighthouses is carried out on a thick gypsum or alabaster mortar.

Preparing the solution. In accordance with the manufacturer's instructions, pour water into a previously prepared container and fill in the dry gypsum mixture.

Advice: It is advisable to mix no more than 10 liters of solution at a time, since this amount is on average enough for 1 hour of work.
If you knead large quantity mortar, it is likely that it will set before it is fully used.

You can find a detailed description of the gypsum putty mixing technology in the relevant articles on our portal.

Apply the first layer of putty. When plastering on the lighthouses, apply the solution from the bottom up to about the bottom of one third of the wall. You can throw the solution into the gap between adjacent lighthouses on a pre-moistened wall with a trowel, or you can apply it with a spatula. The outline layer should be 1-2 cm above the surface of the lighthouses.

We level the applied solution. To do this, we apply a plastering rule to the surface of neighboring beacons and lead it up, periodically shifting the tool from one side to the other. In the process of leveling, putty accumulates on the rule, which must be removed in a timely manner with a spatula and mixed into the bulk of the solution.
After the first layer of plaster dries up, you can proceed to the final leveling. A new putty solution is diluted, which is applied and smoothed with a wide spatula.
The final stage of plastering is sanding the finished surface and applying a layer of primer. After that, the wall covering is completely ready for painting works or for applying decorative plaster.

Features of the use of cement-sand mortar

As already mentioned, before plastering the walls of aerated concrete with a cement-sand mortar from the inside of the room, you need to take care of effective vapor barrier.

Therefore, the instructions for carrying out the work are as follows:

The surface of the wall is cleaned of dirt, after which a film vapor barrier is applied to it. We fasten the vapor barrier film in layers overlapping each other.

We stuff plaster mesh... In this case, it is optimal to use metal mesh chain-link with a cell side of no more than 3 cm.Of course, you can use plastic mesh, but the metal chain-link has a relief, which allows the solution to better adhere to the wall surface.
We fasten the mesh strips vertically with a gap between the previous and the next strip to the width of the beacon.
We install beacons in the gap between the grid strips. We choose the lighthouses so that they are about 5 mm thicker than the grid.
We prepare a plaster mortar in a ratio of 1 part of cement to 3 parts of sand. Mix all the components dry until a homogeneous mass is formed.
After that, add water in small portions to the dry mixture and stir until the solution reaches the required consistency.
We determine the readiness of the solution as follows: we collect the solution on a trowel, tilt the trowel and watch how the solution slides down. The ready-to-use solution slides slowly and does not run off or fall off in lumps.

Sketching and alignment, in this case, is performed in the same way as in the previously described method.
After the sketch and leveling of the solution is completed, the dried surface is rubbed with a foam float. Grouting is carried out in a circular motion with periodic spraying of the surface with water from a spray bottle.
After grouting is done, you can start applying decorative plaster.

Dry plaster technology

When decorating walls of aerated concrete blocks with your own hands, one should not forget about dry plaster. Wall decoration with gypsum fiber board, OSB and other materials in the form of slabs is becoming increasingly popular everywhere.

Of course, this type of finish will be an excellent solution for interior work, while the outside of the walls can be plastered in the usual wet way.

Consider the technique of frame wall cladding with plasterboard sheets, especially since the price of such a solution is available to most of those who wish.

Important: the average cost of a running meter of a frame profile is 30 rubles, while 1 sq.m. drywall will cost from 100 rubles.

Finishing work is carried out as follows:

We equip the vapor barrier of the walls. For these purposes, we use glassine, membrane or polyethylene nonwovens with microperforation. We fasten the vapor barrier with vertical strips with an overlap of 10-215 cm on top of each other.
We mount the crate from metal profile... Until recently, the crate was made exclusively using wooden beam... But wood is a short-lived and expensive material. Therefore, to replace wooden products came galvanized metal profiles, lightweight, inexpensive and stainless.

To decorate the walls inside the room, you will need a guide, post and corner profile.

We fix the rack profile at a distance of 60 cm from each other, while the guide profile can be installed in 1 meter increments. We fasten the profile with special dowels for working with aerated concrete.

Important: To prevent the appearance of the drum effect, mineral wool slabs should be placed between the gypsum board and the vapor barrier.

We fix the drywall boards with self-tapping screws, but not closer than 15 mm to the edge of the sheet.
Install the drywall of the upper row with some offset relative to the lower row.
After finishing the walls, you can start to putty the joints between adjacent plasterboard slabs. We do this using a special mesh tape, which we glue to the joints with a putty mixture.

Output

Now you have got a general idea of what the instructions for decorating walls from aerated concrete blocks are. Despite the fact that there is a widespread opinion about the fragility and fragility of this material, aerated concrete blocks are not much inferior to other building materials.

However, this is possible only if the walls of foam blocks are timely protected with high-quality plaster from negative impact environmental factors. Again, despite the fact that the plaster of such walls is considered problematic, the correct approach to business, in accordance with the above recommendations, will ensure the proper quality of the finished result.

You can find more useful and informative information by watching the video in this article.

Plastering walls: advantages and disadvantages in comparison with other types of finishing works
Construction and renovation technologies are changing, new materials are emerging, but plaster remains a popular way to decorate walls that has stood the test of time. The reliability, solidity and durability of the result obtained are weighty arguments in favor of plastering.

Plasterboard, which gained popularity for its ease of installation and became an excellent option for the ideal leveling of walls, could not completely supplant its "fundamental" competitor. Although communications are conveniently hidden under the sheets of drywall and you can put an insulating layer - this is undoubted advantages, but it does not withstand loads, reduces the area of the room and requires finishing - these are disadvantages.

The process of plastering aerated concrete inside the house, like any other room, is laborious, it takes more money and time, you have to go through a rather "dirty" period, but as a result, the walls acquire a high-quality coating that can last for several decades. Of course, it also requires a decorative finish, but unlike a plasterboard base, its strength will withstand almost any load - shelves and awnings can be mounted on these walls and any design and repair experiments can be implemented.

Plaster can be applied to any surface, except for very uneven walls, which will require a thick layer to level concrete mix... In this case, it is easier and more profitable to use plasterboard finishing.

The choice of material for plastering aerated concrete walls

Aerated concrete ( gas silicate blocks) - relatively new construction material, but received incredible popularity and the title of "revolutionary" in the market. Thanks to its cellular structure, it provides good thermal insulation combined with excellent air and moisture conductivity.
Its excellent air and vapor transmission characteristics place special demands on the technology, the quality of the finish and the materials used.

At first, the finishing material should not drown out these valuable qualities, completely blocking the pores and depriving the house of the ability to "breathe".

Secondly, porous aerated concrete, providing good air exchange, can quickly "dry" a wall finished with plaster and cause cracks on it.

Therefore, the choice of material for plastering aerated concrete surfaces is approached with special care. It is necessary to use specially formulated plaster mixtures marked "For aerated concrete". They contain components that maximally approximate the properties of plaster to the properties of aerated concrete and improve its adhesion, adhesive and vapor permeable characteristics.
In addition, the mortar prepared from these mixtures gains elasticity and resistance and can be applied to the walls in a thin layer.

Sequence of work

For the same reasons, the sequence of work execution has its own specifics: first, the internal walls are plastered, they wait until they dry completely, and only then can the external finishing work begin. Moisture should completely come out from the inside out, and not vice versa.

The plastering process consists of three stages:

preparation of the foundation;
applying a base coat;
applying a topcoat.

Preparation of the base. Gas silicate walls have an even, homogeneous surface with very thin seams, since the masonry does not use concrete, but glue. Smooth surface necessarily requires the application of a primer layer, which strengthens the adhesion of the plaster and the wall and reduces the moisture-absorbing properties of aerated concrete, so that drying occurs evenly.

Base coat application... After the primer has dried, the dry mixture is diluted with water in accordance with the manufacturer's instructions and a base reinforcing plaster layer is applied to the wall with a notched-comb trowel. It is reinforced with an alkali-resistant fiberglass mesh: it is simply pressed into the upper third of the layer with a trowel and smoothed. Mesh sheets are embedded in the plaster with an 8-10 mm overlap one by one. They prevent deformation, shrinkage and cracking.

Sufficient base layer thickness of about 4 mm - special additives in the mixture for work on aerated concrete make it possible to obtain a durable coating with a minimum thickness. The plaster dries for a long time - you have to put up with it. As a rule, 1 mm is allowed to dry for 1 day, thus. the whole layer will dry for about 4 days.

Topcoat application... It is recommended to prime the base reinforcing layer before applying the topcoat. The decorative layer is applied with a metal float. Its thickness depends on the size of the fractions in the mixture - solid particles that give the plaster a relief pattern. For example, if the size of the fractions is 2 mm, then the thickness of the decorative layer should not be more than 2 mm.

Having leveled the plaster and having waited a little while it “grasps”, it is “textured” with a plastic float - they give relief. Some topcoats do not need further painting as they are already contain colored pigments.

It will be useful to know that it is not recommended to start finishing work in a gas silicate brick house immediately after the construction of the frame. The moisture content of the "fresh" aerated concrete block from the plant is high - about 30%, it is advisable to wait about six months for it to dry up to 15%. Aerated concrete walls do not require special insulation, so the house can be operated at first without finishing.

Finishing begins with plastering aerated concrete inside the house, i.e. from the inner walls, but end with the outer ones, and in no case vice versa. Drying should go through the outer wall.

The work is carried out observing temperature regime within the range from +8 to +30 C. Optimally - at 15-20 C.

Subject to the recommendations, the correct technology of work and the choice of appropriate materials, plastered aerated concrete walls will last for more than a decade, providing comfortable air exchange, no dampness and no cracks on the surface.

Before plastering aerated concrete inside the house, let's figure out the properties of this material for the construction of walls. Aerated concrete blocks have a number of advantages, low specific gravity (2 times lighter than silicate bricks). But their plastering is done according to the rules.

Advantages of aerated concrete blocks

The construction of houses using aerated concrete blocks is carried out quickly, since due to the low weight of the material, the laboriousness of wall installation is reduced. Aerated concrete has a low thermal conductivity, so the coefficient of thermal resistance of the material is 2-3 times less than that of ceramic bricks.

The cellular structure of aerated concrete and wood creates the same microclimate in the house. An increase in the density of aerated concrete blocks during their production causes a deterioration in the heat-saving properties of the material. This requires appropriate wall decoration. The porous structure of this material provides excellent sound insulation in rooms. Walls both "breathe" and allow water vapor with carbon dioxide to pass through.

Aerated concrete is good thermal insulation, since it has an open porous structure and great strength, and it is also a fireproof material. Adhesives are used for laying blocks, this helps to maintain the exact geometric dimensions of the building. The very process of building walls does not require professionalism.

Another advantage of the blocks is a reduced sensitivity to the negative effects of the external environment. The disadvantage of aerated concrete is considered to be low bending strength. If we take into account this characteristic of the material, then the construction of a house from it is carried out on the basis of a number of measures.

These include:

arrangement of the foundation of a monolithic type;
reinforcement of floors, masonry, rafter structures.

Rules for finishing a surface of aerated concrete

Before finishing walls made of aerated concrete, take into account that they are very different from brick in their properties. Aerated lightweight concrete has always played the role of insulation. After the insulation of the house from aerated concrete from the outside began to be carried out with the help of special heat insulators, the use of blocks was associated only with the construction of the building structure.

Since aluminum powder is mixed into the raw material for aerated concrete, the structure of the blocks becomes cellular, which increases their vapor permeability. This is taken into account in the process of finishing the walls of a building made of aerated concrete blocks.

Plastering is the most common method used for interior and exterior finishing of vertical surfaces. Before insulating a house from aerated concrete, you will need to plaster the surface of the walls. They begin this work from the inside of the building, after which they move on to finishing and begin to insulate the facade of the house. The mistake will be to first plaster the building on the outside and carry out work on the interior decoration for the cold period of the year.

Most of the water that is used for interior wall finishing works out both through the walls and through the ventilation ducts. Subzero temperature leads to the formation of condensation from water vapor particles inside the walls, as well as on the outside. After the water freezes, the plaster cracks and flakes off. This is proof that it is necessary to plaster aerated concrete walls from the inside of the house, and not on the facade.

Which plaster option to choose

A layer of plaster on the wall should not interfere with its vapor permeability, therefore, a solution of a mixture of cement and sand is not used for plastering the walls. When performing work, one of the methods is used interior decoration walls. The first of them is based on the fact that the material has a special property that ensures the vapor permeability of the walls.

If, when plastering blocks of aerated concrete, a cement-sand mortar is used, then, due to their structure, they will quickly absorb moisture. As a result, the surface of the walls will dry out and become covered with cracks. It will not be possible to correct the situation even after using a deep primer or putty.

Another reason why cement-sand mortar is not used for internal plaster premises, - a low rate of vapor permeability of the walls. When brick house already built, this quality of plaster is no longer important. If aerated concrete was used in the construction process, and not brick, then improper plastering of the walls will cause a deterioration of the microclimate inside the building.

In hardware stores or on the market, special mixtures are sold, with the help of which they perform high-quality plastering of aerated concrete blocks. The finishing is carried out according to the principle of maximum vapor barrier of the blocks. The microclimate conditions inside the aerated concrete house will not differ from reinforced concrete buildings.

The outer layer of plaster will be durable. This is due to the fact that after the time that it takes for the moisture balance to be established in the aerated concrete wall, the supply of steam to the external environment decreases. As a result, the plaster will not flake off from the facade surface.

Materials for the vapor-permeable layer of wall cladding

The use of plaster compounds based on gypsum and gypsum putty increases the vapor permeability of aerated concrete walls. This figure should be high as customers and builders choose aerated concrete. Decoration Materials on the basis of gypsum are produced with the content of slaked lime and light perlite sand. After plastering with these compounds, it is not required to prime the surface of the walls. The finished plaster is able to easily conduct water vapor.

Plastering the walls inside the house using ready-made mixtures with fillers creates a high-quality cladding layer. It includes the following types of fillers:

limestone;
dolomite;
marble.

It is necessary to choose the right fillers and pay attention to the size of their constituent parts. All fractions must be combined in a single lining solution. Manufacturers producing such mixtures have achieved the convenience of their use. The compositions are easy to rub, they differ in the maximum degree of whiteness.

Polymer additives with a high vapor permeability coefficient provide a higher quality coating than external plaster. Aerated concrete has a porous structure, so it makes no sense to immediately apply putty, otherwise you will need a lot of primer. It will no longer be possible to save on it, since this will lead to the fact that the putty will begin to crack and fall off.

DIY vapor barrier cladding

Polyethylene is often used for vapor barrier when finishing the interior surface of the room. This is the easiest method. But often after the work is done, there is an accumulation of water particles and swelling of the plaster.

During the construction and decoration of walls made of aerated concrete blocks, a good vapor barrier is required. Here they use plaster of sand and cement without special additives - dolomite flour or lime. This type of internal plaster can significantly reduce the conductivity of water particles. In this case, the plaster will peel off, but the choice of this technology remains with the developer.

Before performing work on plastering surfaces, the blocks are primed using a special solution. It is applied 3-4 times. Remember that application modern formulations for finishing blocks leads to a decrease in the level of vapor barrier by 25 times. High-quality adhesives, which are widely used in construction, are capable of eliminating the transmission of water particles. It makes no sense to apply putty.

What tools are required

It is necessary to carry out the finishing work of aerated concrete walls with the same tools that are used for ordinary plastering. To prepare the solution, a suitable plastic container is used, in which it is convenient to dilute the plaster. You will need a construction mixer with a stirring pad.

After adding water, the dry mixture is brought to homogeneity and the required density. The proportions of the components of the composition are indicated in the instructions for the mixtures. The plaster is applied to the aerated concrete using a trowel using a throw-over method. You can use a plaster bucket. In some cases, a trowel is used.

The plastered surface is rubbed with a float. To remove excess mixture from a wall that has a large area, use a trowel. Align the wall using beacons. The plaster shrinks between the guides with the rule.

A vapor-permeable finish is also performed using plasterboard panels. Be sure to comply with the process technology:

the inner layer of the finish should not consist of vapor-permeable compounds;
the outer finishing layer should not be made of vapor-proof materials.

After finishing work, the quality is checked using a lath, the length of which corresponds to the height of the ceilings. It is applied to the wall surface in different places horizontally and vertically. This is how all inaccuracies are revealed. A deviation in the range of 6-7 mm is considered acceptable.

Technology for applying plaster to aerated concrete

To finish the interior of the walls made of aerated concrete, use different ways... The simplest of them is the application of a vapor-permeable finish, that is, plaster. Before using it, a number of preliminary works... The very technology of decorating walls made of aerated concrete indoors resembles plastering walls.

Before starting work, the blocks are cleaned of dirt and also leveled. After that, proceed to applying a layer of primer. It must be taken into account that then materials that absorb moisture will be used. The drying time of the primer depends on the type of primer. Usually it does not exceed 3 hours. When the applied composition is dry, proceed to the wall cladding.

The choice of gypsum mixture for plaster is carried out taking into account the purpose of the room. If this living room, for wall cladding they use plaster, which is intended for aerated concrete. The plaster composition for plastering is fixed to the wall mechanically.

Gypsum plaster is used only for finishing dry rooms. It is not recommended to use it in an environment with high humidity, as well as on highly vibrating surfaces. Gypsum plaster perform finishing premises, after which aerated concrete blocks can not be putty.

If the aerated concrete wall surface is constantly in contact with moisture (in the bathroom), then it is treated with special preparations that resist the effects of a humid environment. In 1 hour after application, the composition on the wall is leveled and the final drying and smoothing of the surface are waited.

There are several ways to plaster aerated concrete walls. If you understand the properties of this material, then you will decide on the choice of mixtures and get good result you can do it yourself.

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