How to plaster gas silicate blocks inside and outside, gypsum, aerated concrete, tongue-and-groove, expanded clay concrete: how to do this correctly for the walls of a house?

What is the best way to plaster walls made of expanded clay concrete blocks?

There are a lot of materials on the construction market. Most often, a cement-sand mixture is used, to which PVA glue is added.

You can use gypsum plaster, which is lighter and warmer. But for better adhesion, the wall must be pre-prepared, that is, treated with a gas contact.

In any case, the solution for external treatment of the building must meet certain requirements.

Strength.
Moisture resistance.
In order for the plaster not to fall off, good adhesion of the material itself is necessary.
Plastic. During the shrinkage period, deformation is possible, so do not neglect this point.
Frost resistance.

The instructions are quite simple.

Buildings constructed from expanded clay concrete are finished in most cases, since an unprotected building will not be able to please its owners with durability. As a result of unfavorable natural phenomena, unnecessary moisture appears in the space between the outer and inner base. And it, in turn, will destroy the building material. The external indicators of such blocks will not please with beauty, grace and nobility. How to clad a house made of expanded clay concrete blocks? This question is asked by a large number of people who are constructing such a building. The information below will help you resolve the issue.

How to apply plaster on a wall made of expanded clay concrete blocks

Instructions for applying plaster suggest:

Clean the wall surface from dust, dirty and oil stains, grease, and old finishes.
Seams and cracks are puttied flush with the general plane of the wall. For this, a cement-sand mixture or a ready-made plaster solution is used; you can purchase putty for the seams.
The wall is left to dry.
The surface is carefully primed.
The primer must dry completely.
Cement laitance or a solution of cement and water is prepared.
The composition is applied to the surface with a brush, strokes are made horizontally, which will increase adhesion between the materials.
A reinforcing mesh is placed on the wall.

Tip: If there is no mesh, it should be replaced with steel U-shaped brackets or thin metal anchors with wide washers.

Beacons are set, their control is carried out with a plumb line or level, with a profile pitch of approximately 1.5 meters, in order to work with the two-meter rule.
Lighthouses are mounted on cement mortar.
In a wide tray, as in the photo, a trough or other container, a plaster solution is prepared.
Stir with a mixer or spatula until the consistency of liquid mashed potatoes.

The mortar is thrown onto the wall with a ladle or trowel, the layer is smoothed along the beacons using a plaster rule from bottom to top. In this case, the rule moves slightly from side to side.
After 7 hours, while the first layer has set, the beacons are removed.
Apply the finishing layer with a float or trowel, filling all uneven areas with the mixture.
After the finish has set, the surface is rubbed with a plaster float, moving it in a circle or in a running motion.
After the plaster has dried, the wall is again primed and painted. The surface can be covered with decorative putty or any other finishing material.

What features do expanded clay concrete walls have, plastering them with different compositions, everyone can see in the video in this article.

Walls made of expanded clay concrete blocks must be protected from the outside. Since, despite the strength of the material, it is easily destroyed under the influence of the natural environment, and the appearance of such a wall also requires putting it in order.

One of the simplest and relatively cheap options is plastering walls made of expanded clay concrete blocks.

Building finishing activities

You can clad a house made of expanded clay concrete blocks with the following materials: ceramic facing or clinker bricks, crushed stone, plastic molds, different types of plaster. Taking into account the external nature of the finish, something should be said about the insulating layer.

In most cases, it is installed on the outside of the house. Thus, he is not able to reduce the area of the premises from the inside. Allows you to protect walls and heat-insulating material from the appearance of condensation, which has a detrimental effect on the base of expanded clay concrete blocks.

The following samples are used as insulating components in the design of the external shells of a house:

Polystyrene foam, which is one of the simplest and most popular bases.
Mineral wool, it contains basalt fiber. A material of this nature retains its shape for a long time and is not subject to destruction.
Fiberglass, characterized by low cost.

A house made of expanded clay concrete blocks, like buildings with other design options, is finished from the inside in the same way. To do this, use gypsum and cement-sand plaster. The possibility of decorating with clapboard, plasterboard, and plastic panels is also not excluded. Suitable for this option would be metal profiles and guide bars.

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Wall cladding options

Natural stone or ceramic tiles are determined directly on the surface; there is no need for preparatory work. For better fastening of these materials, use tile adhesive or a mixture of cement and sand.

As noted earlier, the buildings of the sample in question are not left bare, unprotected from the external influences of nature. Of course, if we are not talking about high-quality facing bricks. Despite the fact that buildings made of expanded clay blocks are lightweight, it is very important to correctly calculate the foundation. Therefore, the low weight of such materials does not provide grounds for constructing a lightweight version of the foundation. The disadvantage of such ceilings is their low thermal conductivity. Before facing external walls, care must be taken to carry out insulation measures.

Thus, mineral wool does not burn; a layer of plaster can be applied to it using a special mesh. The same cannot be said about mineral wool. It is intended for decorating a building with siding and other materials in the form of panels. Mineral wool laid under the siding must be protected from the wind. For such purposes, membranes are used that have the properties of protecting from wind and moisture. In this case, the insulation will be dry and provide reliable protection from rain and wind. There are also insulation materials based on mineral wool with a special durable layer on which plaster can be applied.

It is worth noting that the external decoration of the walls of a house with panels made of plastic or siding will not be such a complex undertaking, unlike finishing the surface with plaster. If plastering the base of a house can only be done by an experienced craftsman, then here you can do all the work yourself. Sometimes the method of painting walls without first plastering the surface is used, but it is used very rarely.

One of the frequently used options for finishing the external shells of a house is ceramic, clinker and brick cladding. The least expensive option would be to treat the surface with a layer of cement-sand plaster.

The latter finishing option, together with facade paints, helps to create original surfaces and an unusual appearance. Plaster has the best possible contact with expanded clay concrete; it is actively used for bases that constantly change under the influence of external temperatures and are periodically damaged. The façade, lined with natural stone, looks very beautiful and original. It is not afraid of frost, and at the same time it looks monolithic, chic and unusual. This material can easily be replaced with artificial stone. It is no worse than the natural option, and it costs much less.

As a finishing option, thermal panels made of polyurethane and clinker tiles will complement the external shells of the house well. This finishing method can be called the least expensive. Panels of this type are lightweight and are often used with a strip base. They are strong, environmentally friendly, and create a stable microclimate in the room regardless of the season. Installation work is extremely simple; even a non-professional can do it.

Ventilated facades skillfully hide possible flaws in wall coverings. In the space between the wall and the facing layer there is a constant movement of air, as a result of which the base is not subject to destructive influence. Siding can be considered an inexpensive option for decorating external walls. However, such panels are quite fragile and can break, which does not reflect well on a wall made of expanded clay concrete. Houses made from this material can last a century, but it is important to choose the right finishing option so that the foundation is reliably completed.

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Installation

Plastering of expanded clay concrete blocks is done manually.

Let's move on to practice.

The following are step-by-step instructions for applying plaster to a wall made of cellular blocks:

We clean the wall surface from dust, dirt, grease and oil stains, old finishes, etc.;

Clean the surface.

We putty the seams and cracks so that they are flush with the general plane of the wall. We use a cement-sand mixture or a ready-made plaster solution, you can buy putty for the seams;

We process the seams.

After the joints have dried, carefully prime the wall. When the primer has dried, you can prepare a solution of cement and water (cement laitance) and apply it to the wall with a brush in horizontal strokes, this will increase the adhesion between the materials;

Apply primer.

We stuff reinforcement mesh onto the wall. You can use steel U-shaped brackets or anchors with wide washers made of thin metal;

We install the plaster mesh.

We set the beacons using plumb lines or a level. The pitch between profiles is 1.3 – 1.6 m (for the two-meter rule). We attach the lighthouses to cement mortar;

We display beacons.

Prepare the plaster solution in a wide tray, trough or bucket according to the manufacturer's instructions. Stir it with a mixer or shovel until the consistency of liquid mashed potatoes;

Prepare the solution.

We throw the mortar onto the wall using a ladle or trowel, smooth the layer with a plaster rule along the beacons from bottom to top, slightly moving the rule from side to side;

We throw the solution onto the wall and level it along the beacons.

We wait 6 - 7 hours for the first layer to set, then we remove the beacons and begin to apply the finishing layer using a grater or trowel, filling in all the unevenness;

Apply the finishing layer.

When the finish begins to set, rub it with a plaster float in a circular motion or in a staggered motion;

We rub the surface.

We wait for the plaster to dry completely, then we prime and paint it again. You can also finish it with decorative putty or other finishing material.

We do the final finishing.

Plastering expanded clay blocks

Choosing a mixture for plastering the facade of a building is not difficult these days. The compositions adapted to modern conditions have a very strong foundation. They do not crack and do not fall off for the next season. As soon as the plaster is applied to the wall, it should be covered with any facade paint. Such enamel will protect the walls from unnecessary dampness and interfere with vapor permeability.

Plaster based on cement and sand is applied to the named types of blocks. It matches the masonry. To perform the work better, you can use a special mesh, but this is not a prerequisite. A galvanized mesh of a flat sample is placed on the cement base. It is secured with screws. The washers will be a zinc suspension with perforations, divided into plates. Washers of this type have a minimum thickness and, accordingly, will not increase the plaster layer. Such indicators are very important for some surfaces.

To make your work as easy as possible, plasticizers should be added to the solution.

Plaster made from a gypsum mixture is warmer and airier. It has lower density. To improve adhesion to the wall, it is treated with a composition intended for this purpose. There are ready-made gypsum plasters consisting of concrete-contact ingredients. No preliminary action is required for such reasons. Reinforcement is carried out by using a polymer mesh.

Expanded clay concrete blocks are in demand in modern private construction. Using it you can implement almost any project. But when the object is ready, the question often arises of how finishing work should be done. Houses made of ceramic blocks allow you to implement many tasks.

The main objectives of this stage of work are to improve the exterior of the finished facility, service life without major repairs, and heat conservation. The building's cladding protects the walls from damaging external influences. When constructing a load-bearing foundation, space should be provided for future façade cladding.

Houses made of expanded clay concrete - insulation and finishing

External cladding carries not only a decorative, but also a practical load. Despite the fact that expanded clay concrete is a durable material that can withstand moisture, sharp temperature fluctuations contribute to the gradual destruction of the structure

, it is also recommended to strengthen the wall with reinforcement.

The optimal brand of foam used for insulation is PSB-S-25. The thickness of the material should not be lower than 3-5 cm

Insulation

When working on the facade, the following must be taken into account:

practice shows that one of the best options for external finishing is the laying of a thermally insulating expanded clay concrete block, which compensates for heat loss up to 75%;
additional insulation is mineral wool or polystyrene foam/expanded polystyrene;
the foam is fixed on the cleaned base using an adhesive composition and is additionally secured with dowels. All seams are treated with polyurethane foam;
mineral wool requires stripping, gluing and reinforcing wall structures to increase the strength of the structure;
the use of penoizol will achieve sound and waterproofing and reduce thermal conductivity.

Finishing

The basic principles of work are as follows:

expanded clay block walls lined with brick do not require additional processing, as they have a presentable appearance;
you can use clinker tiles, stone (artificial or natural), thermal panels or siding;
The most common option is to cover the walls with cement-sand based plaster.

Natural stone looks noble and aesthetically pleasing, however, when choosing a material you need to pay attention to its frost resistance

. Brick is not inferior to stone in its functionality and aesthetics, but is much cheaper.

Facade work using thermal panels is an economical cladding method. The panels consist of polyurethane foam and clinker tiles. This is a lightweight material that has shown effective use on strip foundations; in addition, it is very easy to install.

Ventilated facade systems effectively cover all defects in wall structures and prevent their destruction. Siding can be fragile, and its damage during operation negatively affects expanded clay concrete masonry, which is confirmed by photos and reviews related to houses made of expanded clay concrete blocks.

Work with tile or panel materials requires the installation of sheathing. The finished structure can withstand dynamic and static loads

Wet facade on expanded clay concrete walls

The work is carried out after the walls have been leveled, all cracks have been filled with putty, and excess mortar has been removed.

Sequencing:

First, insulation is installed, for which you can use facade foam or basalt wool;
polystyrene foam is fixed with glue and façade dowels, cotton wool is fixed with façade dowels;
facade fiberglass mesh is used as reinforcement, which is attached using the same dowels with fungi;
A two-component plaster or primer layer is applied to the surface;
the plaster is primed with penetrating primer;
high-quality facade systems help maintain the plaster layer in a semi-plastic state, which guarantees long-term operation;
After priming, you can begin preparing the surface for applying a decorative or paint coating.

Among all the options, you can use the following:

decorative smalt plaster;
“fur coat” plaster;
decorative plaster “bark beetle”;
painting with facade paint.

Facade varnishes are often applied to the decorative layer

or other fixing compounds that protect the coating from possible destruction and contamination. Reviews for such houses made of expanded clay concrete blocks have been very positive.

Arrangement of plaster “under a fur coat”

Work can be carried out without insulation or on this layer. The method, known as finishing the facade “under a fur coat,” is carried out using spraying or spraying a solution. This method is less labor-intensive than working with other materials.

Special devices have been created for working with the solution

. The device can be very simple, manually operated, or more technologically advanced, such as an air gun. At the construction site, the required mobility of the mixture is selected and finishing begins.

When choosing materials, you should initially evaluate the amount of work. The final finishing cost may be too high

Application technology

The expanded clay concrete surface is pre-cleaned, the masonry seams are processed, and then it is primed. Next, the surfaces are reinforced with mesh. The prepared solution is applied and, after drying, rubbed until ready for decoration.

Preparing the wall surface

Before plastering, any dirt, dust, oil or grease stains on the wall blocks are removed. The mortar that protrudes above the surface of the masonry gets knocked down.

Seam processing

Cracks and seams are sealed with sand-cement mortar. When they are narrow and deep, they are embroidered to allow the material to penetrate. All recesses are aligned to the plane of the wall to ensure more uniform shrinkage of the plaster. The surface must be dry before the next operation.

Before using the gypsum composition, expanded clay concrete blocks are treated with agents that improve mutual adhesion. Liquid quartz primers, polymer dispersions, as well as “concrete contact” type compositions intended for expanded clay blocks can be used. At the same time, you can use ready-made plaster mixtures that already contain additives for similar purposes. Then the blocks will not require preliminary priming.

Before using a cement-sand mortar to level out the suction properties, the masonry areas are treated with a solution of cement in water. It is also possible to simply wet the expanded clay blocks with water when applying the plaster layer. Properly prepared masonry will evenly absorb water from the plaster solution, which will keep it smooth.

Installation of plaster mesh

The use of sand-cement mortar (up to 10 mm thick) does not require reinforcement. However, when the plaster layer is thicker than 1.5 cm, it is better to fill it with a flat galvanized mesh. Fastening is carried out using self-tapping screws, which are installed in dowels into holes made in the masonry every 20 - 30 cm.

The mesh is pressed with thin washers under the screw heads. A relatively thin layer of plaster coating makes it possible to use fiberglass mesh (density 200 g/m2, mesh 10x10 or 5x5 mm). It is advisable to install it before plastering with gypsum mortar.

Preparation of the solution

The ready-to-use solution should have the consistency of liquid mashed potatoes. Plasticizers will make it easier to use. Also, especially in gypsum plaster, you should add components that increase adhesion to the base. The plaster of expanded clay concrete blocks must provide the masonry with moisture resistance, have high strength, adhere well to the base, dampen minor shrinkage changes in geometry and frost resistance.

Before starting, vertical beacons are attached to the solution and leveled in increments convenient for using the two-meter rule. For the first layer, the mixture is thrown onto the masonry with a trowel and smoothed with a rule that moves along the beacons slightly to the right - left and from bottom to top. After 6 - 7 hours, the beacons are removed from the wall, and a 2nd thin finishing layer is applied, eliminating all remaining irregularities.

The solutions dry out quite quickly, as they dry on the outside. The plaster forms a smooth, even surface from under which the relief of the blocks of expanded clay concrete base does not appear.

As it sets, the finishing layer is rubbed with a grater. Complete drying of the cement-sand coating gives the start to finishing: priming with painting, decorative puttying, priming for wallpaper, tiles, porcelain tiles, etc. Gypsum plaster creates a surface almost ready for decorative finishing (wallpaper, painting). The external surfaces of the building covered with plaster should be immediately covered with façade paint, which will protect them from dampness.

Expanded clay concrete block is plastered to level the surface of the masonry, improve the performance properties of buildings and subsequent decoration. Plaster mixtures have application nuances that require consideration.

House made of expanded clay concrete blocks - interior finishing options

The objectives of this stage of work are to protect the walls from adverse effects, model design solutions, environmental friendliness and comfort of housing. By choosing to build a house from expanded clay concrete blocks on a turnkey basis, you can get a building that is completely ready for use, with completed interior decoration.

Work can be carried out using the following materials:

ceramic tile;
plaster;
lining made of plastic or wood;
wallpaper.

Application of plaster mixtures

This is one of the most economical and affordable options, which makes it the most popular.

Working compositions can be as follows:

decorative plaster – gives the surface a finished, aesthetically attractive look. Various textures and shades are available for sale, including glitter, stone chips, fabric fibers;
starting – used to eliminate defects in the base layer;
finishing – masks the unevenness of the previous coating.

The working mixture is applied to the expanded clay concrete wall using a special reinforcing mesh

, with the exception of decorative coatings. To decide on the choice of plaster, you should focus on the humidity of the room. The most suitable are gypsum mixtures that provide an aesthetic appearance and are used for painting.

The use of gypsum plaster allows you to obtain:

ease of work;
a warmer home compared to sand and cement based solutions;
high adhesion, which is ensured by treating the wall with the “Concrete-Contact” solution.

Cement-sand mixtures have the following properties:

the composition is not much different from standard wall material, which allows you to get an advantage in terms of adhesion to the working surface;
In practical applications, manipulations with such compositions are more labor-intensive.

Technology of applying plaster to expanded clay concrete

Next, we will consider the technology of constructing a plaster layer. First you need to clean the base from dust and dirt. After this, they proceed to puttying unfilled seams and cracks. The work must be carried out in such a way as to level the surface of the wall. At the next stage of work, after the plaster solution has dried, they proceed to applying a primer to the wall. Such a solution will increase adhesion and help strengthen the base.

When the primer is completely dry, a reinforcing mesh is fixed to the surface of the wall, attaching it to the base using metal anchors with thin washers. Next, metal beacons are placed along the width of the rule. When carrying out such work, you need to use a building level and plumb line. The guide rails are fastened to the wall using gypsum mortar or ordinary high-strength cement mixture.

After the beacons have hardened, a plaster solution is prepared and then poured into the spaces between the beacons; a ladle or trowel is used for this purpose. Next, you need to level the mixture with a rule and wait for it to dry. At the final stage of work, the beacons are removed and the surface is leveled. When the finishing layer of plaster has dried, the surface is grouted using special trowels.

Applying plaster is one of the stages of finishing work, which is responsible for protecting the surface from external influences and preparing the basis for further decorative finishing. There is a larger selection of plaster mixtures for sale for each type of laying material. Below we discuss in detail the plastering of walls made of expanded clay concrete blocks - types of mortar, basic properties and method of application.

Blocks made of expanded clay concrete are a popular material for the construction of residential and non-residential buildings. This material has a large list of advantages, among which the following stand out:

Strength and durability;
Resistance to moisture and temperature changes;
Frost resistance;
Environmental friendliness;
High levels of thermal insulation and vapor permeability.

In a room built from expanded clay blocks, there is natural air circulation and it “breathes.” Blocks do not deteriorate over time, do not rot or rust.

Let's take a closer look at how and how to plaster expanded clay concrete blocks? What to use for work? What features should you know before starting work and how to choose the right material?

Houses made of expanded clay concrete blocks, video - working with facing materials

If the owner is faced with the task of interior wall cladding, you can use natural stone or ceramic tiles. No preliminary preparation of the base is required - the tiles are laid directly on the expanded clay concrete wall using cement-sand mortar.

Wallpaper coverings

Standard paper wallpaper has been replaced by more durable and beautiful materials:

non-woven;
cork;
vinyl;
liquid wallpaper;
textile.

This type of finishing work is implemented after preliminary surface preparation. The master can carefully plaster the surface or cover the wall with plasterboard

. Expanded clay concrete can withstand galvanized steel profiles or guide bars well.

The design of the cottage can be implemented in any style. The most popular are house designs made in accordance with the requirements of modern and classic design. In country houses, the “country” or “Provence” style looks especially organic. But, according to reviews from owners regarding houses made of expanded clay concrete, any design project can be easily implemented indoors.

The features of a house made of expanded clay concrete blocks are described in the video:

Many developers believe that finishing expanded clay concrete walls is not necessary. Indeed, a building constructed from such blocks does not require mandatory finishing in some situations - the material is quite resistant to high humidity, temperature changes, and ultraviolet radiation, and can last for quite a long time - several decades. But this is correct if we are talking about some kind of garage, barn or other utility room, where functionality comes first, and parameters such as beauty, aesthetics and the special durability of the building are not very important. But if you want your house to please you and your children and grandchildren, and to last for at least a century, then you should think about it.

In what cases does it make sense to finish a house from expanded clay concrete blocks:

if additional insulation of the room is necessary - external plaster with or without a combination of insulation and a vapor-permeable membrane;
during the construction of a residential building - exterior and interior decoration;
during the construction of basement floors, semi-basements, and other underground structures - a special waterproofing coating on the outside of the walls.

Plastering expanded clay concrete blocks

The construction of houses and other structures from expanded clay concrete blocks has long been firmly established in our daily lives.
And indeed, building a building from such material is much faster than, say, from ordinary brick, and more economical. There are two main disadvantages of houses made of this material: unpresentable appearance and ventilation of the porous structure of the block. In order to improve the walls and get rid of blowing, it is necessary to plaster the surface of expanded clay concrete walls on both sides. Even if you want to clad the house with siding, there should be minimal grouting of the pores under the finishing of the facade. Many developers believe that finishing expanded clay concrete walls is not necessary. Indeed, a building constructed from such blocks does not require mandatory finishing in some situations - the material is quite resistant to high humidity, temperature changes, and ultraviolet radiation, and can last for quite a long time - several decades. But this is correct if we are talking about some kind of garage, barn or other utility room, where functionality comes first, and parameters such as beauty, aesthetics and the special durability of the building are not very important. But if you want your house to please you and your children and grandchildren, and to last for at least a century, then you should think about it.

In what cases does it make sense to finish a house from expanded clay concrete blocks:

if additional insulation of the room is necessary - external plaster with or without a combination of insulation and a vapor-permeable membrane;
during the construction of a residential building - exterior and interior decoration;
during the construction of basement floors, semi-basements, and other underground structures - a special waterproofing coating on the outside of the walls.

Why do you need to plaster the walls of a house made of expanded clay concrete?

As mentioned above, plastering the walls of a residential building built from expanded clay concrete is recommended in most cases. For what? Let's think logically. The building block discussed in this article is essentially expanded clay and a cement binder that allows it to maintain its given shape. At the same time, a huge mass of pores is formed in it, through which air circulates quite freely. As a result, unplastered walls made of such material will simply be blown out, which will make the home cold and uncomfortable.

Plastering only from the inside will not bring much reduction in the level of heat loss, since cold air will also freely penetrate the wall from the street, right down to the inner layers, take away heat, and also escape freely. This is despite the fact that there should be no drafts in this case.

If a decision is made to finish an expanded clay concrete house, it must be plastered, both inside and outside. High-quality external and internal plaster will significantly increase the service life of the walls, and will allow you to fully use the heat-insulating properties of the material - you will get something like a “thermos” that perfectly retains heat.

Types of plaster for finishing the walls of a house made of expanded clay concrete blocks

Depending on the purpose of the room and the functions of the finishing layer, the surface of a house made of expanded clay concrete sides can be covered with:

A solution based on cement and sand. This is the simplest, cheapest (if you take into account only the cost of raw materials) and affordable option. In the recent past, when other types of ready-made dry compositions were not yet widespread on the construction market, this finishing was the only possible one. Note that this option is not the best and has a serious drawback, which will be discussed below.
Special mixtures based on cement, various additives, plasticizers and fillers. This plaster is more convenient to use, more durable, and has a number of positive properties.
Water-repellent compounds - to protect the walls of houses that have to work in difficult climatic conditions, or for buildings located below zero ground level.
Gypsum-based mixtures are used only for interior plaster of residential premises with normal humidity. This finish has its own specifics; a separate section will be devoted to it.

As you can see, the choice is quite large. The basic requirements for any type of plaster are the ability to apply it in a thick layer and good vapor permeability.

The main nuances when finishing expanded clay concrete walls

Let's digress a little from the topic and talk about the material itself. The block, as we have already discussed above, consists of concrete and expanded clay. It has good vapor permeability, low thermal conductivity, and is relatively lightweight. However, its surface is far from perfectly smooth - there may be various pores, cavities, and protrusions. At the same time, it perfectly absorbs water from the external environment (for example, during rain or groundwater). And its geometric dimensions, as a rule, are characterized by significant deviations - up to several centimeters. It goes without saying that a wall built using these blocks will not have a clean surface or evenness. Hence the requirement for the thickness of the layer that the plaster can work with.

Of course, you can use thin-layer mixtures, but, as practice shows, this will be a more labor-intensive, time-consuming and expensive process. In this case, you will need to apply several layers, and each one must gain a certain strength - and this takes time. In addition, you need to provide the embedded elements necessary to connect them, or use a special plaster mesh. Alternatively, the first layer can be made in the form of separate “cakes” applied with a trowel or plaster trowel, which is then well primed after hardening, and after this the surface is finally leveled. As you can see, the process is quite tedious.

Gypsum plaster for expanded clay concrete houses

Let us repeat that any gypsum mixture is used exclusively for interior decoration. And its application has a number of features, which we will now discuss. First of all, the blocks are based on cement, and the plaster discussed in this paragraph is gypsum. These two materials have different pH levels, in other words, an indicator of acidity. Expanded clay concrete gives an alkaline reaction (this is what explains skin irritation when working with cement mixtures), and gypsum shows an acidic reaction. From the school chemistry course we remember what happens when these two media are mixed - neutralization.

Let's get back to practice. Gypsum plaster is applied to a wall made of expanded clay concrete blocks. The contact surface enters into a neutralization reaction - let us clarify that this does not happen quickly, but still, it is necessary. As a result, the interface between the media loses its strength, which can ultimately lead to such an unpleasant phenomenon as peeling of the plaster. What to do in this case?

In fact, the problem can be solved quite easily; you simply need to prime the surface of the walls well, and the primer should be specifically designed for concrete foundations. It is applied in two layers - the first is diluted with water to penetrate deeper into the material and create a strengthened layer. After the first one has dried (this is a very important point), the second one is applied, undiluted, which creates the necessary film at the interface between the media. And only then feel free to use gypsum plaster, there will be no problems.

Priming the surface of the walls should not be neglected when using any type of finish. As practice shows, the adhesion strength of the plaster to the base increases significantly.

In conclusion, we can say that for finishing expanded clay concrete walls, ready-made dry mixtures are suitable, which are used for houses made of gas silicate or foam concrete, which also have high vapor permeability. We can recommend materials such as Baumit HandPutz sand-lime plaster for manual finishing, which has excellent characteristics, or particularly durable acrylic plaster, such as Bolix and Bolix Complex. It is also worth noting the very high-quality and durable compositions based on silicate and silicone, produced by domestic and foreign manufacturers.

Why do you need to plaster the walls of a house made of expanded clay concrete?

If a decision is made to finish an expanded clay concrete house, it must be plastered, both inside and outside. High-quality external and internal plaster will significantly increase the service life of the walls, and will allow you to fully use the heat-insulating properties of the material - you will get something like a “thermos” that perfectly retains heat.

Types of plaster for finishing the walls of a house made of expanded clay concrete blocks

Depending on the purpose of the room and the functions of the finishing layer, the surface of a house made of expanded clay concrete sides can be covered with:

A solution based on cement and sand. This is the simplest, cheapest (if you take into account only the cost of raw materials) and affordable option. In the recent past, when other types of ready-made dry compositions were not yet widespread on the construction market, this finishing was the only possible one. Note that this option is not the best and has a serious drawback, which will be discussed below.
Special mixtures based on cement, various additives, plasticizers and fillers. This plaster is more convenient to use, more durable, and has a number of positive properties.
Water-repellent compounds - to protect the walls of houses that have to work in difficult climatic conditions, or for buildings located below zero ground level.
Gypsum-based mixtures are used only for interior plaster of residential premises with normal humidity. This finish has its own specifics; a separate section will be devoted to it.

As you can see, the choice is quite large. The basic requirements for any type of plaster are the ability to apply it in a thick layer and good vapor permeability.

Types of plaster

Surfaces made of expanded clay concrete blocks are plastered with cement-sand and gypsum mixtures. Plaster reduces the thermal conductivity of walls and provides the correct gradient of vapor permeability. Ease of use and adhesion strength are higher than sand-cement plaster. However, the surface of masonry stones unevenly absorbs moisture from the mortar, which can lead to fragmented shrinkage and disruption of the aesthetics of the surface. Another danger is possible weak adhesion between the plaster and the wall surface.

Cement-sand

Cement-sand mortar for expanded clay concrete.
The plaster goes well with wall blocks due to the identical compositions. It is ideal for tightly closing pores, cracks and smoothing seams, which is important with constant changes in humidity and air temperature. This plaster can be easily painted to form the desired exterior façade or interior walls. Plastering creates additional pressure on the foundation, which should be taken into account.

Advantages

Cement-sand plastering is the simplest and most aesthetic finishing method. The composition of the mixture has high adhesion to the base of expanded clay blocks, which creates a durable coating. It is better to cover masonry in rooms with high internal humidity with this mixture.

This coating saves the project budget.

Plaster

This material has a lower density and increased thermal insulation properties compared to a cement-sand mixture. This type of plaster does not adhere well to the base unless ingredients with concrete contact properties (or ready-made dry mixtures) are used.

Advantages

In terms of performance characteristics, plastering with a gypsum-based mixture is similar to a sand-cement composition. However, the material itself per unit area (with the same layer thickness) is lighter than the cement-sand mixture and somewhat warmer. The exterior of the finished surface can be perfectly smooth.

The main nuances when finishing expanded clay concrete walls

Gypsum plaster for expanded clay concrete houses

These two materials have different pH levels, in other words, an indicator of acidity. Expanded clay concrete gives an alkaline reaction (this is what explains skin irritation when working with cement mixtures), and gypsum shows an acidic reaction. From the school chemistry course we remember what happens when these two media are mixed - neutralization.

Priming the surface of the walls should not be neglected when using any type of finish. As practice shows, the adhesion strength of the plaster to the base increases significantly.

Question: Good afternoon, dear gentlemen! Please tell us how best to decorate the outside of a house made of expanded clay concrete blocks (CBB), what façade would be appropriate here, what materials can be used? Arthur Shakarin, Novosibirsk

Answered by Semyon Fiskunov, Stroy-Alliance CJSC, Tolyatti.

Answer: Hello, Arthur! I'll try to answer your question in detail. Moreover, KBB is a fairly popular material; many owners use expanded clay concrete blocks.

First of all, I would like to ask you a counter question - how thick are the expanded clay concrete walls you built? The question is not an idle one.

It depends on your answer whether you will have to insulate your walls from KBB, or whether you can immediately begin finishing the exterior and applying a decorative layer.

Technology for applying plaster to expanded clay concrete walls

It is not difficult to do the work of plastering walls made of expanded clay concrete blocks with your own hands; it is important to properly prepare the surface and follow the instructions.

Prepare the base - thoroughly clean the surface from dust and dirt, remove debris, remove oil stains, if any. It is necessary to check the interblock seams and knock down the protruding mortar;
Inspect the surface for cracks, seal all found cracks, chips, holes and seams between blocks with cement mortar. Leave the surface until the solution dries completely.
Priming - the choice and method of priming depends on the type of plaster. For cement-sand mortar, priming is not a necessary step. You can get by with plain water, which you apply to the blocks immediately before plastering. When using gypsum plaster, the surface must be primed with concrete contact or quartz primer. For acrylic and silicate plasters, special solutions are also used.

Surface reinforcement – reinforcement is required if the plaster layer exceeds 1.5 centimeters. Experts suggest using reinforcing mesh or fiberglass mesh, the structure is attached with self-tapping screws.
Applying the solution - the prepared solution is laid in two layers. Before starting work, it is necessary to secure vertical beacons, which can be used to navigate in the future. The first layer of plaster is thrown onto the surface using a trowel and carefully leveled according to the beacon rule. The resulting surface is left for 6 hours until completely dry, then all beacons are removed and the finishing layer is applied.

For layer thicknesses up to 15 mm, reinforcement is not required.

Plastering is an important stage in construction; it extends the life of the structure, protects the walls from moisture and temperature changes.

Ventilated façade on KBB walls

If you have chosen a ventilated façade, you can install it in a wooden sheathing or in the space between steel hangers. I do not recommend you insulate a house made of KBB with polystyrene foam under a ventilated façade.

Why? Because there are several reasons why polystyrene foam is completely unsuitable as insulation for a ventilated façade:

Polystyrene foam is a flammable material and cannot be used in systems with a ventilated facade.
Rodents feel great in such a pie if you still make polystyrene foam into the ventilation façade.
The movement of air in the ventilation gap and the moisture being removed will eventually make a set of individual foam balls from sheets of foam. Your insulation will flow down the ventilation gap.

Basalt wool, which you can use, does not have these shortcomings in the ventilation façade. You can also use polyurethane foam, resole foam or ecowool.

After installing the sheathing or hangers and subsequent insulation, you can install the outer decorative layer on the ventilated facade.

What is suitable in this case for a house made of KBB:

Porcelain tiles
Clinker panels
Vinyl siding
Metal siding
Fiber cement panels
Planken
Block house

These materials can be used to form. How to install them - see on this website, everything is described in detail.