Aerated concrete is increasingly used in private construction, competing with traditional brick. Such houses are much warmer, and less time is required for construction. By technical specifications aerated concrete is noticeably different from other materials, and these differences must be taken into account when choosing exterior finishes for walls. The most popular option is plastering, and in order for the coating to best match the base material, you need to choose the right composition.

Let's take a closer look at the types facade plasters for aerated concrete and the correct technology for their application.

Aerated concrete has a cellular structure with open pores, which provides not only thermal insulation properties, but also high vapor permeability. Thanks to this quality, an optimal microclimate is created inside the house, the accumulation of condensation is eliminated, and the risk of mold development is minimized.

But there is also back side: open pores increase the hygroscopicity of the material, and absorbed water destroys the cells when freezing. For this reason, the exterior finish must be waterproof in order to reliably protect the walls from moisture, and have a vapor permeability no lower than that of aerated concrete, so as not to prevent the escape of fumes.

Important! According to the standards prescribed in SP 50.13330.2012, in heated houses, the vapor permeability of materials should increase from internal to external layers. Only under such conditions is normal functioning of load-bearing structures possible. Since for aerated concrete this parameter varies between 0.11-0.23 mg/(m h Pa), the plaster composition must be selected with a vapor permeability of at least 0.12 mg/(m h Pa).

Additionally, facade plaster must have the following qualities:

• high adhesion to the base material;
• frost resistance (minimum 35 cycles);
• increased compressive strength;
• resistance to atmospheric influence;
• decorativeness.

In principle, aerated concrete surfaces can be used without protective coating, but after a few years the external attractiveness will disappear: the blocks will darken, peeling will appear, and mold may develop. So it is better to immediately complete the façade finishing and then only periodically update the coating by painting.

Prices for aluminum stairs

Aluminum ladder

Types of plasters for aerated concrete

The most common and most budget plaster for external work - cement-sand. But since its vapor permeability is only 0.09 mg/(m h Pa), it is not at all suitable for aerated concrete structures. Other types have the necessary parameters plaster mixtures, such as mineral, silicate and silicone. Let's look at the characteristics of each of them in more detail.

Mineral

Plaster on mineral based refers to inexpensive materials and it’s easy to do it yourself. The main disadvantage is the limited color range, but since this coating is very paintable, this is not such a big problem. Ready-made mixtures contain lime, white cement, marble chips and other fillers, as well as some additives that improve the quality of the plaster. Homemade mixtures are most often made from cement, lime paste and sand, or only from sand and lime. It is worth noting that sand-lime mortars have low water resistance, and direct exposure to precipitation is detrimental to them.

Silicate

In silicate plaster, liquid potassium glass plays the role of a binder. Such compositions are more convenient to apply, are not afraid of moisture and perfectly allow evaporation to pass through, which allows them to be successfully used for finishing aerated concrete walls as finishing coating.

Silicate plaster - photo

The color range is quite limited, but, again, this drawback is easily eliminated by painting. Silicate plaster goes on sale in a ready-to-use form, and the cost is slightly higher than dry mineral mixtures.

Silicone

The basis of silicone plaster is silicon-organic polymers. She has best characteristics compared to other types of plasters: does not absorb water, is easy to apply, resistant to atmospheric influences, vapor permeable and does not lose its visual appeal for a very long time. In addition, such a coating remains elastic and does not develop cracks when aerated concrete blocks shrink. Silicone plasters are also sold ready-to-use and have many color options. Thanks to the presence of special fillers, silicone plasters make it possible to create a varied coating texture. The only negative is the high price of the material, so not everyone can afford such finishing.

Acrylic

But acrylic plasters for aerated concrete can only be used under the condition of enhanced waterproofing with inside walls and high-quality ventilation premises. This is due to the low vapor permeability of the material, which is closer to cement-sand compositions. If you do not provide sufficient protection internal surfaces, water vapor will begin to accumulate in the thickness of the walls and provoke peeling of the finishing layer.

Popular types of plaster mixtures for aerated concrete blocks

Name	Characteristics
	Dry mixture on a mineral basis. It is distinguished by its plasticity and ease of application. Ready solution must be used within an hour. Application thickness – from 3 to 30 mm. After drying, the coating can withstand temperatures from -50 to +70°C, and at least 100 freezing cycles. The dry mixture consumption per m2 is about 14 kg when applied 10 mm thick. The coating can be painted 7 days after application.
	Cement-lime dry mixture. It has good resistance to shrinkage, adheres firmly to the base, and is not afraid of moisture. Applied in thicknesses from 5 to 30 cm, consumption - 14 kg with a layer thickness of 10 mm. The prepared solution must be used within 3 hours. The frost resistance of the coating is 50 cycles and can be used in temperature range from -50°С to +65°С
	Ready-made mixture based on silicone resins. Very plastic, firmly adheres to the base, forms a strong coating with dirt- and water-repellent properties. The palette includes about 200 colors and shades. Consumption is 2.5-3.9 kg/m2, depending on the thickness of application
	Plaster composition based on silicone emulsion, ready for use. It has different grain sizes - from 1.5 to 3 mm, and is tinted in more than 200 colors and shades. The coating is moisture resistant. Pollution, exposure to ultraviolet radiation and temperature changes. Consumption is 2.4-4.7 kg/m2
	Ready-to-use silicate plaster. It has a grain size from 1.5 to 3 mm and 200 tinting options. Forms a dense coating with high vapor permeability and moisture resistance. Approximate consumption 2.5-4.2 kg/m2
	Acrylic composition with mineral filler. Can be used for exterior finishing of aerated concrete blocks if there is internal waterproofing and ventilation of the premises. Forms a thin but durable coating that is resistant to negative influences. Has frost resistance up to 100 cycles, consumption is 4.5-5.2 kg/m2

Prices for various types of decorative plaster

Decorative plaster

Technology for plastering aerated concrete facades

Conditions for work

It is possible to plaster a facade made of aerated concrete only after all “wet” processes inside the room have been completed and the surfaces have completely dried. This applies not only to plastered and painted walls, but also to screeds on the floor, moisture from which evaporates very actively. The blocks themselves must also be dry - the maximum permissible humidity is 27%. If you plaster wet walls, intense release of water vapor will cause peeling of the coating.

It is recommended to plaster external walls at a temperature of +5...+30 °C, while the relative humidity should not exceed 80%. If for some reason it is not possible to complete the exterior finishing before the onset of frost, you need to treat the entire area with a primer deep penetration. The best option– primer Ceresit ST-17, applied in 2 layers. This protection will be sufficient until spring, when weather conditions allow plastering to begin.

Advice. Cannot be applied plaster compositions in the heat, when strong wind and when the walls are exposed to direct sunlight. These factors contribute to the rapid drying of the solution, and it does not have time to firmly adhere to the base. As a result, many small cracks appear and the plaster peels off.

Prices for deep penetration primer

Deep penetration primer

Surface preparation

As a rule, walls made of aerated concrete blocks are quite even and smooth, so there is no need to specially level them. If there are deep chips or dents, you need to repair them with the glue that was used when laying the blocks.

To do this, mix a little glue (you can mix it with the dust formed when sawing blocks), scoop it up with a narrow spatula and fill the recesses. Remove excess and allow the solution to dry. Empty seams between blocks are sealed in the same way. When the glue dries, the walls need to be rubbed down to remove minor flaws. Use a metal flat grater for this. Finally, sweep away dust from the entire surface with a brush.

Padding

For priming aerated concrete walls under plaster, deep penetration compounds with strengthening properties are used. They create a very strong elastic film that allows water vapor to pass through, but does not allow the material to absorb water. Additionally, such primers increase the adhesion of the base and finishing layer. Popular products: Knauf Grundiermittel, Siltek E-110, Aerated concrete-contact-1.

The primer is applied in 1-3 layers, depending on the climatic conditions of the area. For example, in dry and warm regions one layer of primer is sufficient, but in areas with a damp climate, coastal areas, three layers are needed. To apply the composition, use a roller or a wide paint brush. Prime with a continuous layer, evenly distributing the composition over the base. In corners and hard-to-reach places, use a narrow brush so that there are no dry areas left.

Plastering and reinforcement

It is not necessary to reinforce a layer of plaster up to 10 mm thick if the walls are properly primed. For larger thicknesses, reinforcement is indispensable, and for this purpose a fiberglass mesh with cell sizes of 3x3 mm is used. The mesh must be alkali-resistant - this will ensure high durability and strength of the finishing layer. This information is indicated on the packaging, so when purchasing a mesh, pay attention to this point.

Step 1. Cooking plaster mortar. The proportions of water and dry mixture are in the manufacturer's instructions, so read it carefully before starting work. To knead, take a clean container and pour the specified volume of water at a temperature of +15…+20 °C. Pour in the dry ingredients and stir with a construction mixer at a speed of 400-800 rpm. Let the solution sit for 5-7 minutes and stir again.

Construction mixer price

Construction mixer

Step 2. Take a wide metal spatula, apply the solution to the edge and apply it to the wall in an even strip. The spatula should be held at an angle to the surface and not pressed too hard, so the composition will be distributed most evenly. The layer thickness should not exceed 5 mm.

Step 3. A mesh is placed on top of the mortar, straightened, and then carefully deepened into the plaster, rubbing it forcefully over the surface with a spatula. If necessary, add the solution in small portions and rub thoroughly again. Having secured the mesh, apply the solution to the next area and repeat all over again. The mesh must be overlapped by 40-50 mm to avoid cracks at the border of adjacent areas.

Step 4. Special perforated profiles with a mesh attached at the edges are attached in the corners. To do this, apply the solution to the very corner, level it in height with a spatula, and apply corner profile and press gently. Then, like the mesh, it is deepened into the plaster and the surface is smoothed with a spatula. They are placed not only on external and internal corners, but also around the perimeter of window and door openings.

The corners and mesh should not protrude above the plane of the wall anywhere. The surface must be flat, smooth, without visible defects. Now you need to let the solution dry thoroughly. Drying time depends on the composition of the mixture and weather conditions, on average it ranges from 3 to 7 days.

Finishing layer

Mix the solution for the finishing layer and apply it to the surface with a wide spatula. The thickness of this layer varies between 4-10 mm. Special care is required here, since all defects will remain visible. When plastering adjacent squares, the formation of stripes along the edges should be avoided; all excess should be removed immediately with a spatula.

When the plaster has set sufficiently, but has not yet hardened completely, begin grouting the walls. For this, it is most convenient to use a polyurethane grater, but a metal one will also work. The grater must be applied flat to the surface, pressed, and smooth the plaster layer with circular movements. Do not press too hard to avoid leaving scratches and dents.

After grouting you need to wait completely dry plaster, and only then proceed to the final stage - painting. You can also use decorative structural plaster by applying it thin layer on a prepared base.

Video - Facade plaster for aerated concrete

Currently, building material such as aerated concrete is becoming increasingly widespread. For the construction of a low-rise building, it is optimal solution. Active use of aerated concrete in modern construction due to the low cost of blocks, low specific gravity, high thermal insulation properties, opportunity machining hand tools, high fire safety.

However, after completing the main construction work The question inevitably arises about further interior and exterior decoration of the house. Exist different kinds finishing, but greatest distribution It was plaster that got it. Let's try to figure out how to plaster aerated concrete inside the house.

Plaster options for finishing aerated concrete walls

In addition to the above advantages that have ensured the popularity of such a building material, it also has disadvantages that require a number of additional rules to be followed during construction. finishing works. These disadvantages of aerated concrete include:

• High vapor permeability;
• The ability to absorb moisture very quickly and in large quantities;
• Fragility.

The first two disadvantages have a particularly important effect on aerated concrete plaster. It is the high level of adhesion that significantly complicates the finishing process both inside and outside the house. There are three options for plaster for aerated concrete walls:

1. Cement - sand;
2. Plaster;
3. Facade.

It is important to note that no matter what material you choose for plastering, finishing aerated concrete walls should begin with interior work. This is due precisely to the high vapor permeability of aerated concrete. When performing external plastering, the humidity of the room increases significantly, which can negatively affect the quality of interior work.

Decorating the walls inside the house can serve two purposes:

1. Maintaining or even increasing the vapor permeability of aerated concrete. This option is used if the main purpose of finishing is to create an optimal microclimate in the house.
2. Complete vapor barrier. This option is used if outside surface aerated concrete is also plastered; in this case, the release of steam to the outside is minimized, which has a positive effect on the durability of the external plaster.

Now let's consider which material will be most suitable for plastering your home.

Cement-sand plaster. Often, many people wonder: is it possible to plaster aerated concrete with cement mortar? Decorating walls with such material is extremely undesirable for the following reasons:

1. The vapor permeability of cement is significantly lower than that of aerated concrete. Provide an optimal microclimate in aerated concrete house is possible only if the vapor permeability of the finishing material is equal to or exceeds that of aerated concrete.
2. With significant moisture absorption rates, aerated concrete will intensively absorb moisture from the sand-cement mortar, and this will significantly reduce the quality of the plaster, since the acquisition of optimal strength parameters by cement plaster is possible only if it dries slowly and evenly.
3. Low adhesion and high specific gravity solution excludes the possibility of its reliable adhesion to the material.

Plaster. Plastering aerated concrete inside a house with gypsum has its advantages and some disadvantages. The advantages include:

1. 1. Quick drying;
2. 2. No shrinkage;
3. 3. Possibility of obtaining a smooth surface;
4. 4. By skilfully plastering a wall made of aerated concrete, you can avoid applying the finishing layer. It is unlikely that the quality of the surface will allow for tinting, but gluing wallpaper is quite acceptable.

The disadvantages of gypsum mixtures include:

1. Low vapor permeability;
2. A fairly large volume of water is required to mix the mixture;
3. High adhesion of dried plaster to precipitation and moisture in general.

Despite these disadvantages, plastering aerated concrete with gypsum is quite acceptable.

Facade. This type of plaster mixture is optimal for plastering aerated concrete indoors and outdoors. The vapor permeability indicators of this composition correspond to those of aerated concrete blocks, they are characterized by high adhesion, and they are also distinguished by good aesthetic properties after drying.

Interior decoration of aerated concrete house

Currently, there are a large number of ready-made dry mixtures for plastering walls. When choosing a material for plastering work, the following factors must be taken into account:

1. The plaster mixture must have good vapor permeability parameters, at least equal to those of aerated concrete;
2. Excessive amounts of water should not be used to prepare the working mixture.
3. The selected mixture must have a high coefficient of adhesion to the base;
4. The plasticity of the plaster should provide the walls with resistance to cracks;
5. The frost resistance of the selected mixture must correspond to climatic conditions;
6. The time before the newly prepared mixture begins to set, in other words, the time during which the prepared mixture has sufficient plasticity for application to the base.

Currently, in the market of dry mixes for plastering aerated concrete, with a huge variety of choices, in terms of price-quality ratio, Ceresit CT 24 confidently leads.

In conclusion, I would like to remind you that regardless of what you use to plaster aerated concrete, compliance with the technological regimes specified by the contractor of the plaster mixture is directly related to the quality and durability of the work performed. The preparation of the foundation should not be neglected. Preliminary removal of various irregularities in the masonry will allow you to significantly reduce the layer of plaster applied to aerated concrete, and, consequently, its consumption.

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

Requirements for plaster

The range of products for the job is quite large, but not all of them are suitable for gas silicate plastering. The surface of the material is porous, which causes difficulties. Let's consider the requirements for the plaster mixture:

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

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

Which mixture to choose

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

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

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

Note! It’s better to do the plastering yourself, as the price of a professional’s work can be steep. Plastering 1 m2 of wall will cost 300 rubles, priming and putty – another 300 rubles/m2, reinforcing the wall with mesh – 100 rubles/m2, finishing painting – from 120 rubles/m2.

The nuances of working with gas silicate blocks

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

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

Arsenal for plaster

Let's begin with plastering work will be carried out using beacons. This will make the surface perfectly flat and will simplify the task for beginners. Below is a list of tools that will be required for the job:

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

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

Preparatory stage

It all starts with preparation. It is very important, since the final result directly depends on it. The instructions are:

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

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

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

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

All that remains is to install the beacons along the drawn lines. Installation is carried out using mortar or fasteners. If the walls are relatively smooth, you can get by with fixing it to a mortar, which is applied in small portions along the line at intervals of up to 20 cm. The profile is sunk into the mortar and aligned using screwed-in screws. Now you can apply the plaster.

Plastering walls

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

1. Using a trowel or ladle, the composition is applied to the wall in a thick layer. The work is done from below, moving upward. You should not fill the entire wall, but only one section of the two beacons.
2. Then, using the rule, the gas silicate plaster is stretched and the surface is leveled. In this case, the movements should be zigzag, starting from the bottom, moving up.
3. Excess composition is thrown on top. Work continues until the entire section is filled and perfectly level. Advice! The thickness of the layer depends on the location of the beacons. If the thickness exceeds 3 mm, then a reinforcing mesh is needed. It is sunk into the solution. The surface should be smooth and without wrinkles.
4. According to this principle, the entire surface of the wall made of gas silicate blocks is processed. Particular attention should be paid to the corners. They must be smooth and well reinforced.
5. When the wall is processed and has dried a little, the beacons can be removed from the walls. After them, the grooves will remain without solution. They are also filled with the mixture and leveled.
6. The evenness of the resulting wall is checked using a level.
7. When the surface has dried, you can begin sanding the walls. It is done with a grater and a grater.

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

Let's sum it up

By doing all the work yourself, you can save tens of thousands of rubles. The money saved can be spent on quality furniture Decoration Materials or something different. If this is your first time doing this work, it is better to study the entire process in detail and only then start plastering gas silicate blocks. Doing everything yourself is quite possible. All that remains is to put all this into practice.

Internal and external aerated concrete plaster must have optimal parameters, protecting the walls of the structure from destruction and cracks under the influence of external influences. There are several basic options for finishing mixtures that will improve and maintain the quality of the base. The right technology application will ensure a long service life and decorativeness of the coating.

Aerated concrete has good thermal insulation properties and a high degree of vapor permeability due to its porous structure. It will help preserve the quality of the material by preventing the accumulation of condensation and the occurrence of mold. correct finishing aerated concrete.

In this article we will answer the main question, how to plaster aerated concrete outside and inside the house.

Aerated concrete blocks

Basic requirements for plaster

It is worth immediately noting that ordinary plaster It is not recommended to apply it to a house made of aerated concrete blocks. First of all, because standard sand solutions differ high density, this leads to poor adhesion when applied to an aerated block and the rapid appearance of cracks.

Adhesion(from Latin adhaesio - adhesion) in physics - adhesion of the surfaces of dissimilar solid and/or liquid bodies.

The plaster should maintain an optimal microclimate inside the building, protecting the walls from moisture. Therefore, you should choose mixtures with a vapor-permeable base. Otherwise, the steam coming out of the house will get stuck inside the walls, since the plaster will simply block its exit to the outside. Thus, moisture will begin to accumulate in the walls, which will ultimately lead to their destruction. Of course, nothing will happen to the house in a few years, but in six to eight years, an almost irreversible process of destruction will begin.

Plaster for aerated concrete should be:

• resistant to external weather influences;
• have good adhesion (adhesion to aerated concrete);
• resistant to sudden temperature changes;
• high degree of compressive strength (protection against cracking);
• vapor permeable;
• moderately dense;
• improving the thermal insulation of walls;
• have a decorative appearance.

When choosing plaster for aerated concrete, you should not ignore any of the points listed above.

Applying plaster to a house made of aerated concrete blocks

Absence facade finishing structures made of aerated concrete will lead to darkening, deformation, and peeling of the surfaces of the blocks.

Types of plasters suitable for aerated concrete blocks

The choice of plaster mixture for aerated concrete primarily depends on whether you are going to cladding the walls from the outside or from the inside. Based on the type of application, plasters are divided into external and internal.

As you understand, external plaster is intended for finishing facades. Because here she performs protective functions, its strength, moisture resistance and thermal insulation indicators should be higher.

Internal mixtures are intended for finishing indoor walls, so the presence of moisture resistance in the characteristics of these plasters can be ignored, with the exception of cases of wall cladding in the bathroom. Due to the lack of resistance to moisture, internal mixtures are much cheaper than external ones.

Applying a finishing layer of plaster to aerated concrete

Popular plasters for aerated concrete

Mixtures for finishing facades made of aerated blocks are divided according to the type of composition into:

• lime-cement;
• acrylic;
• silicate;
• silicone.

Lime-cement mortars quite durable and at the same time vapor-permeable, because their main component is lime, which replaces sand. Eliminate low level water resistance, elasticity and limited selection color palette material can be made using various additives. Modern ready-made mixtures contain special fillers that improve the properties of the coating.

Acrylic It is advisable to finish a building made of aerated concrete only if there is high-quality internal insulation of the walls. Such plaster cannot boast of good vapor permeability, but in quality decorative finishing, it is durable and reliable.

Silicate plaster for aerated concrete is produced on the basis of liquid potassium glass. The coating has good moisture resistance, vapor permeability and durability. The silicate solution is easy to apply. The finishing layer is resistant to dirt and abrasion, providing a decorative finish for a long time (more than 25 years). The problem with silicates is the limited choice of colors.

Leveling walls with silicate plaster

Silicone mixtures contain resins and organosilicon polymers. Qualitative characteristics materials are optimal for creating a durable coating. Silicone-type plaster retains elasticity after application, which ensures the absence of cracks on the surface even when the blocks shrink. It is important to note the special decorative quality of the finish; thanks to special fillers and color variations, you can create original look façade.

Silicone plaster can undoubtedly be called a leader among others; it has all the advantages of silicate compounds, moreover, it is durable and looks great. But the price of silicone mixtures is much higher than others.

On our website you can find contacts construction companies who offer the service of designing houses made of aerated concrete. You can communicate directly with representatives by visiting the “Low-Rise Country” exhibition of houses.

Most popular manufacturers

The building materials market is saturated with a huge number of plaster mixtures various brands for finishing aerated concrete surfaces. Popular formulations have optimal characteristics for carrying out work.

Applying plaster to interior walls houses made of aerated blocks

Ceresit CT 24. The mineral composition of the mixture gives the solution plasticity. The material is easy to apply. The coating can withstand up to 100 cycles of low temperature influences. It is recommended to paint after complete drying (after seven days).

CERESIT ST 77. The acrylic type of the mixture is used for facade finishing, ensuring the strength of the coating with a fairly thin layer of application. The material is frost-resistant and resistant to external influences. Used when there is waterproofing and ventilation inside the house.

Founded by Startwell T-21. Cement-lime plaster is frost-resistant and has a sufficient level of adhesion. The resulting coating is resistant to shrinkage and moisture.

Video description

Watch the video comparison of facade plasters for aerated concrete:

Baumit Silicone Top. High level adhesion and plasticity are achieved thanks to the base of the mixture - silicone resins. The coating remains decorative for a long time due to its dirt-repellent properties. Wide choose palette of paints of the material (up to two hundred shades).

Weber.pas silicone. Mixture based on silicone emulsion. It is possible to select the appropriate grain size. Optimal resistance of the material to moisture, temperature, and dirt.

Baumit Silikat Top. Silicate type of plaster. The coating is durable and has good vapor permeability. The composition has different grain sizes and up to two hundred tinting variations.

Priming the surface before plastering

Internal plaster of aerated concrete walls

Internal work on plastering walls made of aerated blocks is carried out with gypsum solutions with various additives. Composites in the form of perlite, marble chips will increase the decorative effect of the finish. There is the possibility of painting the composition in various colors.

Gypsum mixtures without additives have the required level of vapor permeability, which allows the plaster to be used as a base for wallpapering. Standard sequence of work:

• elimination of irregularities and chips on the surface of the walls;
• removing dust and applying the first layer of solution;
• installation of reinforcing mesh;
• applying the second layer.

After complete drying, you can glue wallpaper, paint the walls, or apply a third, decorative layer of plaster.

Interior work is carried out only subject to the preliminary application of a waterproofing compound and priming.

Interior wall plaster

External plastering of aerated concrete walls

Plaster for aerated concrete facade view can be applied when using various technologies: thick-layer or thin-layer finishing. The sequence of work includes:

• mandatory preparation of wall surfaces, leveling;
• priming (compositions based on acrylate siloxane);
• applying a thin layer of solution - the basis for attaching the mesh;
• reinforcement (protection against cracks);
• leveling the finishing layer;
• second layer of coating (formation of a smooth, even surface);
• finishing layer plasters, grout.

One year after completion facing works, it is recommended to apply a water repellent solution. Thanks to the treatment of the façade with this composition, the moisture-proof and water repellent properties coverings.

Features of plastering walls made of aerated blocks

Proper execution of the work must take into account the characteristics of the material of construction. Aerated concrete blocks may have differences in structure. Sawn options have an open, pronounced cellular structure and do not require special preparation for finishing.

The formed blocks are covered with a hydrophobic layer with a buried pore structure and require additional processing. Grinding the surfaces with a wire brush will help improve the adhesive properties of the material.

Video description

Watch the video of the process of applying plaster to a house made of aerated concrete:

It is also important to remember the rule of increasing the degree of vapor permeability from the inner layer to outer surface. The façade finish should be twice as thin as the interior coating.

It is strictly not recommended to carry out plastering work on aerated block surfaces earlier than 6 months after the construction of the walls. The structure must dry completely, getting rid of excess moisture accumulated during laying of the material.

Plastering on reinforcing mesh

Optimal conditions for applying plaster

Exterior plaster aerated concrete must be produced under certain conditions. It is important to complete first interior work increased humidity levels. Bearing structures walls made of aerated blocks must be completely dry, not exceeding 27%. Otherwise, high humidity will cause adhesion failure and lead to peeling of the finishing layer of the facade.

The optimal time for finishing the interior of the house is spring, the façade of the building is the end of summer.

External temperature conditions for work must correspond to +5-+30°C, with air humidity not exceeding 80%. If it is necessary to perform finishing at low temperatures temperature indicators, it is recommended to use a special deep penetration primer before the onset of acceptable weather conditions.

Carrying out the work correctly will help avoid peeling, cracks and defects. It is forbidden to apply the coating in hot weather, under direct sunlight and in windy weather.

Plastered facade of aerated concrete house

Conclusion

Choosing a high-quality solution for plastering aerated concrete structures will help improve performance characteristics material, will create strong and durable surface protection.

Aerated concrete is gaining increasing popularity as a building material. And this is not surprising. Big sizes blocks can significantly reduce construction time, and the cellular structure retains heat, allowing you to reduce heating costs. But this material requires serious protection from moisture.

Aluminum powder is added to the basic solution from which aerated concrete is made. At one stage of the technological process, this component releases gas, forming cells filled with air. In this case, the pores remain open and moisture quickly accumulates in them.

Therefore, the material is protected from precipitation both at the stage of wall construction and after the “box” of the house is ready. Moisture accumulated in autumn or spring time, will also quickly go away when exposed to sunlight. But in winter this factor will be destructive. And over time, small cracks will appear on the walls, and then peeling.

In addition, aerated concrete has the following characteristics:

• Low thermal conductivity.
• Strength depends on the foundation. If it shrinks strongly, then cracks will soon appear on the gas block.
• Durability if the material is protected from water.
• Fire and environmental safety.
• Soundproofing properties.
• High vapor permeability, which makes homes comfortable, since internal vapors quickly escape outside rather than accumulating indoors.
• High levels of moisture absorption, which forces the house to be lined with moisture-repellent materials.

When is the best time to plaster aerated concrete walls?

Most often, plastering is chosen for finishing aerated block walls. But you need to choose the right time to complete the work, as well as the appropriate composition. We’ll look at the type of plaster for the facade a little lower, and now we’ll look at the timing of the finishing work.

1. You should not plaster immediately after construction. The walls are given time to completely dry and shrink. It's enough to wait a year. If this is not done, cracks will appear on the finish.
2. Choose a warm season when the night temperature does not drop below 0 degrees. In such a situation, the moisture that the aerated concrete absorbs from the solution will quickly be released and the finish will dry.
3. To protect the walls from moisture and frost in winter, they are covered with deep penetration soil. Under such protection, the house will withstand the load of one frosty season without changes in the structure.
4. Polyethylene film is also suitable as a barrier for unlined walls.

Is it necessary to first insulate the outside?

As mentioned above, the walls from this building material retain heat well. Therefore, if you correctly calculate the thickness of the structure, there is no need to insulate the house. It is better to do this by using the services of professionals. They take into account the climatic conditions of the region where the structure is being built.

You should not make the walls too thin so that they need additional insulation, since choosing insulation will be difficult. The aerated concrete structure has high vapor permeability, and if the thermal insulation does not cope with this task, then condensation will appear with outside walls. This will lead to both the destruction of aerated concrete and insulation.

If it is necessary to carry out insulation, then choose a material that can allow steam to pass through from the interior. According to the rules prescribed in State acts, the vapor transmission capacity from the internal walls to the external decoration should increase. Only in this case will it be comfortable to be in the rooms, and mold and mildew will never settle on the walls.

What mixtures are best to use?

When choosing a mixture for plastering aerated block walls, note the presence of the following properties:

• Moisture repellent.
• Good adhesion to the base.
• Low temperature resistance.
• Elasticity.
• Decorative.

Range construction stores offers several types of plaster mixtures. They all have positive and negative aspects to use. It is especially important to use for plastering aerated concrete. suitable options. Therefore, we will consider each type separately.

Lime-cement

This is an example of thin-layer lightweight plaster. It is used only for interior work. It is not worth using ordinary cement mortar. It does not have the necessary characteristics to preserve the properties of our material. But with the addition of lime, everything changes:

1. The mixture adheres well to the base.
2. Apply a thin layer.
3. The vapor permeability of the solution increases.
4. The finish is durable.
5. Inert to the appearance of mold fungi.
6. Affordable low cost.

There are, of course, several disadvantages:

• The finished solution hardens quickly, making it difficult to work with, especially for a beginner.
• Large expense for square meter implies an increase in costs, even with a low cost product.
• The solution is prepared independently, since only the dry mixture is sold.

Acrylic

This option is used for decorative facade finishing of aerated block houses. It is applied in a thin layer, but has a number of advantages:

1. durable;
2. elastic;
3. resistant to low temperatures;
4. the color retains its original brightness for a long time;
5. helps strengthen the foundation in places where the load is increased;
6. repels moisture.

Despite the large number of advantages, there are some disadvantages that raise serious doubts about the correct use of acrylic compositions for aerated concrete:

• Low vapor permeability. Waterproofing is installed on the base or a ventilation system is built in the house.
• Acrylic composition is highly flammable, so it is not suitable for wall areas near fire.
• High price.

Silicate

Great for both indoor and outdoor use exterior finishing compositions based on liquid glass. This plaster is sold only in finished form. Mix it thoroughly before use. The main advantages are:

1. vapor permeability;
2. moisture-repellent properties;
3. large selection of textures;
4. affordable price.

But before plastering aerated concrete, it is worth studying the disadvantages that exist here, like any other material:

• Dirt and dust accumulate on the finishing surface, which reduces the attractiveness of the coating.
• Small selection of colors and shades.

Silicone

This option is made on the basis of silicone emulsions or resins. It is excellent for finishing facade walls. It has the following undeniable advantages:

1. Hydrophobic (repels moisture, practically does not get wet).
2. Vapor permeability.
3. It’s easy to apply, making it suitable for those who decide to do it themselves.
4. Plastic.
5. Crack-resistant.
6. Retains its original color for a long time.
7. Easy to clean from dust and dirt.

The only drawback is the price, which is an order of magnitude higher than previous options. But is it worth saving your time and day if the material has so many advantages?

Cement-sand

The most famous and affordable option plaster mixtures, which are perfect for different substrates. But aerated concrete cannot withstand the use of a cement-sand mixture. Everything is due to the lack of certain characteristics.

Is cement mortar suitable for these purposes?

If a beginner gets down to business, then he should learn all the intricacies of plastering aerated concrete. One of these nuances is the impossibility of using a conventional cement-sand mixture. The reasons for this are:

• Low steam transmission capacity.
• The solution has a large amount of moisture. The gas block quickly absorbs water and then releases it for a long time, which increases the time required to complete the work. Besides cement plaster With the rapid evaporation of moisture, it loses strength, resulting in cracks.
• Aerated concrete has a smooth surface, and the cement-sand mixture has low adhesion rates. Therefore, the solution does not adhere well to the base and can slide off during work. To avoid this, the walls are coated with aerated concrete primer, but this does not always help.

1. Add to ordinary solution lime.
2. Mix a special mixture for aerated concrete blocks and cement mortar in a 1x1 ratio.

What about adhesive for porous concrete?

Special glue mixture, which is intended for laying aerated concrete, should also not be chosen as a material for plastering walls. Although the glue was developed taking into account all the nuances of using a porous material, it is not suitable for plaster:

• Apply only a thin layer.
• Designed for grouting joints.
• Does not have the ability to pass steam. Which leads to the appearance of condensation on the internal walls, and then mold.

This material is used only for its intended purpose.

Interior decoration

It is customary to carry out internal leveling of walls using plaster first. Thus, the moisture that is absorbed from the solution will leave the thickness of the wall faster. on internal walls made of aerated concrete are not much different from plastering other surfaces. Follow this plan:

1. Preparing the base. Removal of bumps and other irregularities. It is better to do this while the walls are being erected, since in the future this will lead to increased waste of mortar.
2. Padding. It is advisable to choose deep penetration soil, especially for rooms with high humidity, for example, a bathroom or a kitchen. Never dilute the primer with water. This reduces the quality of the soil layer.
3. – help control the thickness of the applied layer. The distance between elements is slightly less than the length of the rule.
4. Spray or throw on the first layer. The solution should not reach the top edge of the beacons.
5. Forming corners using a perforated profile with reinforcing mesh.
6. Applying the second layer. The thickness will be less. The solution is also poured, but is immediately leveled by the rule. At the same stage, beacons are removed.

If the surface is to be painted or covered with wallpaper, the surface should be made perfectly smooth. To do this, apply a finishing layer and rub it in.

Outdoor

After the interior work is completed, they begin to improve the façade. Be sure to check the dryness of aerated concrete. Plaster applied to wet walls may peel off. It is also important to choose the weather conditions:

• The optimal temperature is from +5 to +25 degrees Celsius.
• No wind.
• Air humidity is no more than 80%.
• It is better to hide the walls from direct sunlight.

Preparing the wall

Aerated concrete has a smooth, even surface, and therefore there is no additional need to level the walls. But during the masonry process, sometimes small voids appear in the seams or chips on the blocks. They are sealed with the same glue on which the material was laid.

All flaws are filled with the solution and left until completely dry. Therefore, the treated areas are rubbed with a metal grater in order to remove the protruding solution. Remove dust with a brush or damp cloth, but make sure that the material is not too wet.

Padding

For priming façade walls choose deep penetration formulations. They create a durable film that prevents the absorption of moisture, but at the same time steam passes through quietly. Also, an additional layer will increase the adhesion of the plaster and the base.

The soil is applied in several layers, depending on the climatic conditions of the area. To do this, use a roller or brush. The composition completely covers all walls without bald spots. If there are corners or other inaccessible places, they are treated with a small brush.

Plastering and reinforcement

Reinforcing mesh must be used, even if the layer is small, about 1 cm, and the base is well treated with soil. This will make the plaster layer durable and reliable. Select a fiberglass product that is resistant to alkali.

Reinforcement and plastering are carried out simultaneously, following the following plan:

1. Cutting the mesh into strips.
2. Prepare the solution according to the instructions indicated on the package if you purchased a dry mixture. The finished solution is simply mixed so that all components are evenly distributed.
3. Scoop the solution onto a wide spatula and spread it evenly over the surface, about 0.5 cm thick.
4. A special perforated profile with reinforcing mesh is applied to the corner. The mesh is smoothed over the applied solution.
5. Next, separate pieces of mesh are laid. Be sure to make a 5–10 cm overlap. The reinforcement is smoothed by immersing it in the solution. In places where it shows through, add a little mixture and smooth it out again.
6. The surface is treated in small areas with a view to full use ready solution.

After the entire facade has been plastered, it is left to dry completely. There should be no imperfections or protruding reinforcement on the surface.

Finishing layer

Choose as a finishing coating decorative composition. The solution is either prepared according to the instructions or mixed in a container. Apply with a wide spatula. The layer does not exceed 0.5–1 cm. At this stage, work especially carefully, since the remaining flaws will be noticeable.

When the layer dries a little, it is rubbed and either a smooth surface or a texture is created, respectively. Then the layer must dry completely and only after that you can start painting, if necessary. , in this case, is selected as carefully as the mixture for plastering.