What kind of plaster is better to plaster foam blocks. How to plaster walls from a foam block - we get a perfectly flat surface

The construction of the walls of the house from foam blocks makes it possible to significantly save on thermal insulation, building materials, and speed up the work. For comparison, a wall made of foam concrete 300 mm thick in terms of thermal insulation qualities is only slightly inferior to a wall of 2 bricks with a gap of 50 mm, the price is equal to a brick without insulation, and it is built 3-10 times faster. It would seem - why not build all the houses from foam concrete blocks?

The answer to this question lies in the need for high-quality and expensive plaster, which will allow foam concrete to perform its functions for a long time, protect it from dirt, moisture, weathering, chemical decomposition and cracks. For a number of reasons, the traditional cement-sand composition is not able to effectively perform these tasks for foam concrete:

1. Foam concrete has a high vapor permeability, and a regular solution has a low one. As moisture condenses at the boundary of the materials and freezes under the influence of frost, the plaster will inevitably fall off. Additional insulation with vapor-proof materials will only aggravate the situation - a few severe frosts are enough for the insulation to fall off along with part of the foam concrete.

2. Any types of foam blocks have low adhesion and tear strength. Heavy cement mortar without additional tricks will not stick to the wall of them.

3. Foam concrete is a porous material that absorbs water like a sponge. If you apply a mixture that is not supplied with additional additives to retain water, the plaster will not harden, but will dry out, so that it can be brushed off the wall by hand.

To properly plaster the walls of the foam block, they work according to the following scheme:

• The outer layer is made of light, specially designed for gas or foam concrete mixtures with high vapor permeability. Be sure to reinforce the material and prime the base.
• Inside, light mixtures with low vapor permeability are used, if the same material is used, the thickness is increased by 2 times. If it is necessary to plaster the walls with a layer more than 2 cm thick, reinforcement is necessary, in this case it is possible to apply multi-layer plaster with the main part of a cement-sand mortar.

Step-by-step instructions on how to plaster foam concrete walls

Preparatory stage:

• It is necessary to clean the wall, if possible - the adjacent floor, so that the fallen solution does not have to be thrown away.
• To increase adhesion, foam concrete should be coated with a special liquid hydrophobic deep penetration primer with a roller or sprayer, wait for it to dry, and process again.
• When using injection-molded foam concrete blocks, you first need to peel off their smooth surface with sandpaper.

Reinforcement installation:

1. Outside, the most commonly used is a 120 mm galvanized metal mesh fixed with dowels or nails. Due to the twisted spatial structure, it can be applied directly to the base.

2. Indoors, a fine-mesh alkali-resistant fiberglass network is more often used. To fix it, a thin layer (1 cm or less) of a compound with increased adhesiveness, such as inexpensive tile adhesive, is applied to the wall. Using a spatula with teeth, the mesh is sunk into the solution, creating a semblance of corrugation on its surface. This should be done with horizontal movements so that there is maximum bonding with subsequent plastering.

Installation of beacons:

• They take a T-shaped profile for lighthouses, aluminum, if there is an intention to leave them in the wall, or steel, when it is planned to remove them.
• Lighthouses are placed vertically, at a distance of a meter from each other. A larger distance will make it much more difficult to work with the rule, even if there is a fairly long tool.
• The two extreme beacons are aligned with the help of a tape measure and a level, a thread is pulled between them, along which the remaining beacons are set. As reference points, other protruding elements on the wall are also taken into account - window, doorways, ready-made plaster.
• Primary fastening of beacons is carried out on 2 points of support, if the thickness of the plaster is less than 4 cm, installation using continuous gluing is possible. For work, use a thick, quick-setting gypsum adhesive, or a greasy cement-gypsum mortar.
• If the thickness is more than 4 cm, or the profile is too thin, after leveling, each beacon is additionally strengthened by placing it on the mortar with an interval of about 30 cm.

Application of the main layer:

1. Laying is carried out in several approaches, first throwing a rough thick layer without much leveling, cutting off the excess along the beacons, after it has cooled slightly, a second, thinner one is applied and leveled with the rule.

2. If the plaster thickness is more than 4 cm, several base layers may be required, each of which must be allowed to cure completely before applying the next. For better adhesion, the surface of the inner layers should not be leveled.

3. The solution is applied by throwing on the wall using a special ladle, or with a plastering machine. It is customary to work from the bottom up, but this is not important.

4. The mixture for the base layer should have a semi-liquid consistency, similar to milk porridge - the ideal composition is liquid enough to splash out of the bucket, but not flow down the wall under its own weight.

5. If you want to plaster the wall of the foam block from the outside, use ready-made mixtures with high vapor permeability and adhesion, or lime mortars. Inside, the same mixtures are rarely used, since they must be supplemented with vapor barrier wallpaper. It will be cheaper to apply cement plaster on the ground from a highly adhesive tile adhesive.

Coating and grouting:

• The coating solution is made from the same mixture as the main layer, but diluted to the state of liquid sour cream and passed through a fine sieve.
• The cooled (but not dried!) base layer is covered by splashing, leveling with the rule.
• When the coating has cooled a little, it is grouted with a wooden grater. Grouting is carried out in a circular motion with light pressure, after it there should be no small flaws, holes, bumps on the surface. Additionally, it is undesirable to wet the wall during the grouting process.

After gaining strength, you can extract the beacons. With careful movements, the lighthouse is hooked from one edge and removed with minimal damage, the remaining strobe is covered up.

Compositions for plaster

For external work on foam concrete, the most popular are:

• Cement-lime mortar - a greasy mixture with the addition of 1 part lime paste to 5 parts cement.
• Ceresit CT 24, Knauf Grünband, Pobedit TM-22 - the most popular highly adhesive vapor-permeable mixtures from well-known manufacturers, based on cement and various additives.
• Various types of light thin-layer plasters based on lime - Baumit HandPutz, ATLAS KB-TYNK.

Less popular are silicate, silicone plasters. Acrylic does not pass steam well, so it is undesirable to use it. In addition, the second layer in outdoor work is often used decorative types materials.

For indoor work, you can take a highly adhesive mixture based on cement or gypsum - all the compounds already mentioned, mixtures for tile installation, and so on. Any material will work as a second layer.

Common mistakes when plastering walls from foam blocks and tips for eliminating them

1. The largest and gross mistake, common among non-professionals who do everything with their own hands, is the decision to plaster walls built from foam blocks, first from the outside. Any, even the most vapor-permeable plaster creates obstacles to the passage of moisture, which is absorbed by concrete in large quantities during internal works. This will lead to a noticeable weakening of the strength and insulating characteristics of foam concrete in the first winter.

2. Many incorrectly believe that an increase in the binder in the solution always leads to an increase in its strength. This is far from the case - too greasy mixtures harden faster and have greater adhesion, but they are quite fragile and crack easily, therefore they require additional protection.

If you plaster the walls in 2 layers, it is necessary to make the one adjacent to the ground from greasy solutions, and the main one from lean or normal. Approximately for cement, a mixture with a ratio that is a multiple of the brand is considered to be a normal solution, for example, 1 part of cement to 4 parts of sand for grade 400. For fastening beacons, a fiberglass network, you need to use a ratio of 1 to 3, for the base layer, 1 to 4, or even 1 to 5 for interior work.

3. If you choose a mesh for reinforcing plaster that is not protected from the effects of alkalis, over time it will crumble into dust. The metal must be galvanized, and other materials must be marked accordingly.

4. It is almost pointless to install fiberglass reinforcement close to the base - the solution thrown from above will simply press the mesh against the foam concrete blocks, preventing it from performing its functions. This mistake tends to be made not only by amateurs, but also by lazy professionals.

5. Between the installation of the fiberglass network and further work, it will be correct to withstand a technological break of several days. If you start plastering the walls immediately after the first layer has hardened, there may be problems with the strength of the beacons and with the setting of the entire surface. The fact is that for adhesion it is necessary that a certain amount of water passes from the solution into the base. A hardened but very damp inner layer of plaster will not absorb water from the outer.

6. Some work is rather inconvenient to do on your own, it is advisable to involve at least one helper who will knead and supply the solution, help move the goats.

7. Plastering requires a temperature of 5 to 30 °C, so it is advisable to start in the spring.

It is absolutely not necessary to completely plaster the walls of the house from foam blocks with expensive ready-made mixtures, but you will have to purchase some of them. By following all the recommendations of this guide, you can independently perform all the work using simple procedures, ensure the durability of the house with your own hands, without spending extra hundreds of thousands of rubles.

The foam block is affordable option for the construction of residential buildings. It has excellent performance in terms of preservation and heat and strength, so that the rooms will always be warm, and the building itself will last a very long time.

But such material must be protected from external influences. Plaster often acts as a barrier, therefore, before starting work, you should carefully familiarize yourself with all the intricacies of the process.

This construction material needs protection. Everything is related to its structure. The foam block on the surface has a large number of pores, and in his body there are many voids filled with air. Due to this, the material passes air and steam well, but at the same time absorbs a lot of moisture from the environment.

If in summer this fact does not pose a serious threat, then water, freezing in cold weather, destroys the structure of foam concrete from the inside. And this means that the material loses its strength. In addition, the attractiveness of the blocks is not at the highest level. Therefore, plaster performs the following functions:

1. Protects the structure from moisture.
2. Reduces the effects of temperature fluctuations.
3. Gives the building an attractive appearance.
4. Allows you to increase the already good performance of thermal insulation.

But when choosing a plaster mix, make sure that the composition has the same vapor-permeable properties, otherwise all the advantages of this building material will be reduced to zero.

The main problems when performing outdoor work

The foam block material is whimsical and not every novice builder will be able to cope with plastering. During the execution of the work, several problems pop up:

• Moisture from the solution is quickly absorbed into the building material. As a result, the mixture hardens too quickly and unevenly, and this is fraught with the appearance of cracks. Before applying the solution, the foam block must be moistened with water. But make sure that there is not too much liquid, otherwise the layer will dry for a long time.
• Bad adhesion. Homemade cement plaster mortar will not adhere to the surface of the foam block. He just slides off.

To get rid of the last problem, professionals choose the following options:

1. Wall treatment with a special primer composition designed for concrete surfaces.
2. The use of reinforcement. To do this, use fiberglass or metal mesh. You can also use a fishing nylon net with a mesh size of not more than 5-6 cm.
3. Selection of the correct composition for plastering. The selected packaging should be marked that the mixture is suitable for concrete work. The recipes for preparing the solution are exactly the same.

If you apply all three methods to solve the problem, it will be quick and easy, and the layer that forms as a result will delight the owner's eyes for many years.

Dew point

When the owner chooses the method of warming the house, the material and its thickness, he does not even think about such an indicator as the dew point. Most likely none of those who do and do not know about it.

The dew point is the temperature of condensation, that is, the value of the air temperature at which water droplets appear on the wall. A related concept is the place where dew falls - this is the part of the wall where condensation forms. May appear:

• on the inner surface of the wall - indoors;
• inside the wall;
• from the outside - on the street.

If you choose the wrong thickness of the insulation, then condensation will form inside the premises or in the wall itself, which will lead to constant dampness in the rooms and the appearance of fungus. And also, to the premature destruction of the main structure.

When the heater correct thickness and laid according to the instructions, then the dew appears only on the outer surface of the walls, from where it is quickly removed by air currents. In this case, neither the building material nor the insulation suffers, and the indoor climate is at a comfortable level.

Which mixtures are better - examples of brands

When choosing a composition for plastering a foam block facade, pay attention to the following composition indicators:

1. Plasticity and elasticity.
2. Moisture repellent properties.
3. Good adhesion to concrete.
4. Resistance to negative external factors.

Only if the mixture meets the above requirements, it can be used for plastering foam blocks. On sale there are specialized formulations for this material. They can be used for both interior and exterior decoration.

Manufacturers:

• CAVERPLIX TS117 - the cost for 25 kg starts from 454 rubles.
• Ceresit ST 24 - price for 25 kg - 420 rubles.
• PROFIT CONTACT MN - for 25 kg you need to pay 155 rubles.
• BELSILK T-32 - the cost of a bag of 20 kg from 373 rubles.
• ATLAS KB-TYNK - price for 30 kg - from 488 rubles.

Necessary tools and materials

Before proceeding with the work, it is necessary to collect all the inventory. It is much easier when everything is at hand and you do not need to be distracted looking for tools. Therefore, they collect the following set:

1. Metal brush for cleaning walls from the outside.
2. Primer.
3. Brush or roller for applying primer.
4. Reinforcing mesh.
5. Perforator or construction mixer.
6. Plaster beacons, as needed.
7. Dry mix for plaster.
8. Containers for the preparation of the solution.
9. Building level.
10. Spatulas of various sizes.
11. Rule.
12. Plastic graters.

Preparation for work

Be sure to prepare the base before plastering the foam block wall. The preparatory stage is just as important as the plastering process. If the walls are not properly treated, the applied layer will not last long and the owner will waste his time and money.

Therefore they do the following:

• Remove the mortar that protrudes from under the blocks, or the old decorative lining.
• Remove all fasteners or hinged structures.
• If there are cracks or cavities, they are sealed with a rough mortar.
• Clean the surface from dust, dirt and mold.
• Apply a primer.

How to prime the walls?

Priming walls has its own characteristics, which both novice builders and experienced craftsmen need to know about. Since the foam block has a smooth surface, the plaster mortar is poorly fixed on it. The primer will create a base on which the mixture will lie smoothly and reliably.

Because they cover facade walls primer solution 3 times:

• 1 layer penetrates the thickness of the material;
• 2 layer forms a suitable surface;
• The 3rd layer provides the connection between the plaster mortar and the bottom layer.

Each subsequent layer is applied only after the previous one has completely dried. You can start plastering only when all layers are dry.

Attention! Do not buy a cheap option, it is better to spend a little more and be sure of the reliability of the work performed.

Plastering technology

In order for the applied layer of plaster to remain clean and dry evenly, it is necessary to choose the right weather conditions:

1. Air temperature in the range of 5-25 degrees Celsius.
2. Humidity of the environment is not more than 80%.
3. Windless, cloudy weather.

It is better to start work after the base dries out from the dew, somewhere around 11 hours. They work according to the following technological plan:

• . For beginners, this step is required. With their help, it is much easier to make a flat surface. During the installation process, use building level for horizontal and vertical correction. Lighthouses are fixed to the draft solution (in this case, they can be removed after the first layer of plaster has dried) or to mechanical fasteners.
• Preparation of plaster mortar. The manufacturer indicates the instructions on the packaging. Do not deviate from the recommended proportions, otherwise the solution will not adhere well to the base.
• Application of composition. To do this, use wide and narrow spatulas. With a small tool, apply the solution to a large one. Further, with arc movements with a large spatula, the mortar is evenly distributed over the wall. If beacons were installed, then the solution is thrown onto the bases and leveled using the rule.
• Reinforcement. After the first layer has set, a reinforcing mesh is installed. It is fixed with dowels. Thus, the design will be more rigid and securely fixed to the base.
• Application of the second layer. The solution is thrown onto the wall and leveled in such a way as to completely hide the reinforcing mesh. The second layer is made thinner than the first.
• If the plastered layer is subsequently covered with facade paint, then the surface is puttied. In this case, the wall will become smoother.
• There is another option. The facade can be covered with decorative plaster. Then the composition is chosen according to the same criteria as the usual mixture for processing the facade. The construction market offers big choice decorative plasters with different ways creating drawings.

Before use decorative plaster or putty, the surface is once again treated with a primer, which makes it possible to more reliably adhere the two layers.

Inner work, how to do it right?

Plastering work inside the premises is not much different from the outside. The main thing is to strictly adhere to the work plan and not deviate from it even a step:

1. Wall cleaning. All protruding sections of the solution are removed with a metal brush. The dirt is also removed. Pay special attention to greasy stains. If it is impossible to clean it, they proceed to drastic measures. The place is cut down and sealed with a rough mortar. Dust is removed with a damp cloth or brush.
2. The walls are treated with a primer. As during outdoor work, at least three layers of a composition that increases the adhesion of the building material are applied to the foam block. Each layer is left to dry completely.
3. If many mistakes were made during construction and as a result the walls turned out to be completely uneven, plaster beacons are installed. It is much easier to level the surface on them, although you will have to work a little to level them.
4. Installation of reinforcing mesh with dowels.
5. Solution preparation.
6. Throwing the mixture on the wall and leveling the rule.
7. The next layer of the solution is applied only after the first one is completely dry.
8. The third layer will be the finish and should be perfectly even. If it is decided to cover the walls with tiles, then it is not necessary to apply the finishing layer. Glue for finishing material Easily hides small imperfections. In addition, a slight roughness will help the adhesive composition and the wall surface to firmly hold together.
9. The final stage is decorating the walls in any chosen way.

Although plastering a foam block is not so difficult, it takes a lot of time and effort to do everything efficiently. In no case should you neglect the advice of professionals. This will greatly simplify the task.

What is a foam block? This is a fairly relevant and popular building material on the modern market, it is distinguished by its strength, excellent vapor permeability and very lightweight design. A significant disadvantage of foam blocks is poor shrinkage, due to which the material dries out and carbonization occurs, and also such building material does not have a very attractive appearance. But such minor flaws can be corrected by plaster.

At correct use plaster mixture, you can get rid of all the shortcomings of the material, as well as increase its strength and extend its service life.

Positive properties of plaster for foam blocks

Advantages of facade plaster:

• It perfectly protects the house from excess moisture and dampness.
• Enhances the properties of the base material, improves its positive qualities.
• Creates a healthy indoor climate.
• The house is better ventilated, there is much more air in the room.
• Easy and convenient to use.

Stucco is best suited for finishing various buildings using foam concrete. It significantly improves all the qualities and characteristics of concrete structures or materials based on concrete. It also solves a number of problems of this material, better retains heat in the room, protects against excess moisture, oversaturation with dust or carbon dioxide, causing the walls to shrink.

Plastering foam blocks reduces the negative impact low temperatures and increases the service life of foam blocks. She creates protective layer which prevents harmful fumes from entering the room with inside bearing walls, this process helps to remove all the formed steam outside the room. Plastering foam blocks does not allow excess moisture to accumulate inside, and provoke the development of bacteria and fungus. For better vapor permeability, it is best to apply plasters on both sides.

Facade plaster - how to choose the right one

In order to choose a really good plaster, you first need to prioritize what qualities you need more. The plaster has in its composition various connecting elements, depending on their types and qualities, the properties of the plaster will also depend. Plaster happens different types, has various features and characteristics, as well as each of the types has its own method of application.

Plaster consumption

The consumption of plaster is approximately two and a half, three and a half kilograms per square meter. And the service life of facade plaster will depend on weather conditions and climate in the area in which the building will be built. In temperate climates, it can last up to 15 years.

It is worth choosing a special plaster for finishing surfaces, and it is the one that consists of a cellular structure. This composition of the mixture has good adhesion and high optimized properties. In addition, such a mixture is much more elastic, has excellent vapor permeability. Such a mixture is made on the basis of gypsum.

To work with walls from individual blocks produced by casting, in this case, it is necessary to choose a mixture with increased adhesion characteristics.

Varieties of plaster for facades:

1. Elastic facade plaster. It is used for the final stage of facade finishing. It is easy to work with it, using it you can create various patterns.
2. Wet plaster. It is used to insulate the wall surface in buildings that have a decorative coating.
3. Silicone plaster. The most popular type of plaster, due to its versatility and protective properties.
4. Acrylic finish. Used to improve the ventilation properties of the wall. Suitable for climate zones with frequent temperature changes.
5. Facade mineral plaster. The most budget. Thanks to the use of this mixture, the wall surface becomes much stronger and moisture resistance increases. When used, it can give the building different colors.
6. Silicate plaster. Ideal for buildings using blocks with a porous structure. This mixture has high level vapor permeability. It is completely immune to external pollution.

Surface preparation of foam blocks

Foam blocks are made using a special molding technology. The material is poured into special molds in which it hardens and forms, the process is quite simple. The unprotected surface of the material, during drying, tubercles and irregularities begin to appear. When removing the material from the molds, it is very easy to damage them, small chips and irregularities may appear, especially at the corners of the product.

Foam block in forms

In the production process, a special oily composition is used to easily dismantle the formwork, which can subsequently remain on the surface of the foam blocks. This contributes to poor adhesion of the entire product. In order for the adhesion of foam blocks to be better, the surface of the product should be cleaned with sandpaper or simply processed.

Also, for the production of foam blocks, another method is used - sawing. In this case, the mixture is poured into one continuous mold until hardened. Then they are taken out and cut into pieces. right size. Walls made of foam blocks made in this way are much easier to plaster, this is due to the rough cut surface, which helps the material adhere better.

Recommendations for the correct implementation of plaster foam blocks

In the process of plastering, the layer thickness of the applied mixture and its air permeability play an important role. Due to the observance of these two characteristics, the steam that has entered the structure completely will exit through the plaster and the walls will breathe.

With improper plastering, steam will remain inside, negatively affect the walls, thaw and freeze. Such processes will adversely affect the structure, mold will begin to develop, excess moisture will accumulate in the plaster itself, which will subsequently crack and crumble.

In order for the walls to breathe, the thickness of the layer of the applied mixture must be twice as thick as the outer one. The foam block should not be plastered with a thick layer of the mixture, due to poor moisture absorption, the plaster will dry for a very long time. If you decide to use ordinary plaster, then when finishing the injection foam block, it is better to use a special reinforced mesh, it will improve adhesion.

Walls that absorb moisture worse, concrete and foam concrete should be plastered several times. The first step is spraying the walls with a solution, and after complete drying, applying a second, basic layer. For painting plastered foam concrete walls, special facade paints based on silicone or silicate are used.

How to plaster foam blocks outside, the question arises immediately after installing the plane. And this is not an unimportant question. The material absorbs moisture and exterior finish required.

The better to plaster the foam blocks inside, we will consider today. You will find out the most acceptable options and make right choice. And the video in this article will help with this.

Why finishing is required

The best option used when carrying out finishing work on internal surfaces, as well as for facing various aerated concrete and foam concrete structures, is plaster. To date, it is professionally selected and perfectly applied plaster that is able to optimize various (including technical, operational, insulating) characteristics of building materials that are made of foamed concrete.

There are a number of positive aspects when plastering with this group of building materials:

• Protection against the adverse effects of high humidity;
• Increasing the thermal insulation of structures;
• Increasing the resistance of building materials to sudden temperature fluctuations or other negative aspects that can reduce the life of buildings;
• Prevents saturation of building materials with carbon dioxide and dust, due to the interaction with which the shrinkage of structures can accelerate;
• Possibility of free removal of household fumes through the thickness of buildings from the inner surfaces of load-bearing walls.

Attention: The ability of plaster to pass steam makes it possible to avoid the appearance of moisture on the surfaces of foam blocks and aerated concrete walls, which significantly reduces the resettlement of fungi and various bacteria, due to which the building material may prematurely collapse.

So:

• The best option is to finish the surfaces of the walls with plaster on both sides, which allows them to "breathe".
• In the event of obstacles to the release of steam, foam concrete and aerated concrete blocks wear out rather quickly, and it becomes necessary to frequently carry out repair work on a plastered surface. So, after several cycles of freezing and thawing, the moisture that has accumulated under the finish can contribute to the appearance of various cracks and, as a result, the integrity of the plaster may be compromised.
• The presence of "double-sided" plaster allows you to perfectly remove household gases to the outside, and fresh air is able to freely enter the premises.

What mixture to choose

The plaster on the foam block is selected depending on the place of work.

There are two solutions here:

Types of blocks and their influence on the choice of plaster

Initially, the creation of foam concrete blocks was considered as the appearance of a new insulation. Over time, large blocks began to be used in the installation of partitions and load-bearing structures, which was explained by the simplicity of technological work.

It was here that the question of finishing work arose, since many types of putty and plaster simply did not stay on the rather smooth surface of foam concrete products.

So:

• At the moment, in the arsenal of builders there are two options for foam concrete blocks made various technologies. This explains the differences in one building material that sounds like a “foam concrete block”. The foam block than to plaster depends on the environment in which it is located.
• Molding technology in the manufacture of foam concrete blocks. By this method, the solution is poured into a specially designed cassette, where the formation and complete drying of this building material takes place. The surface of the block with this technology contains irregularities and protrusions, and during the extraction of the block from the mold, chipped corners of the finished product are possible.
• Such blocks, as a rule, are dark in color, have damage at the corners and contain residues of an oily composition on the walls, which is used for stripping. These features explain the insufficiently good adhesion of the plaster to the walls of the blocks; therefore, to improve adhesion, the necessary area is cleaned and treated with sandpaper.
• Sawing method for the manufacture of foam blocks. The technology of this method is based on the ebb of a sufficiently large foam concrete product, which is subsequently sawn into certain building elements according to standard or individual requirements customers. The surface of the walls of such blocks is rough, which greatly facilitates the process of plastering.
• The range of products presented in building supermarkets allows you to choose the optimal compositions for plastering surfaces with a cellular structure, in particular, on foam concrete walls. As a rule, these mixtures have a gypsum base and are characterized by increased adhesion, elasticity and vapor permeability. Thanks to the implementation of the manufacturer's recommendations, preparing such a composition is quite simple.

Attention: In the process of work, it must be taken into account that the plaster of foam concrete walls that were made by casting, in contrast to blocks made by sawing, may require a mortar with increased adhesive properties.

Preparatory work

Before proceeding with the plastering of foam concrete walls, in without fail the required area is processed with a soil solution, which will serve as the basis for the plaster.

Attention: It is preferable to use mixtures with deep penetration and apply them twice.

• The quality of the plastered exterior walls of structures can be improved by applying a primer that has hydrophobic substances in its composition. And the treatment of the top layer of plaster with a specially designed water-repellent impregnation will help to avoid the spread of cracks along the outer layer of the coating and further cracking of the plaster.
• Improving the adhesion of the surfaces of foam concrete walls with plaster is facilitated by a reinforcing (fiberglass) mesh attached before plastering, which has an increased resistance to aggressive alkaline environments. This technique significantly strengthens the strength of the areas and is recommended for use on problematic surfaces, which include window and door openings, joints of adjacent surfaces.
• The thickness of the finishing plaster should be no more than 2-3 cm, since structures built from foam concrete blocks do not require a thick layer of it.

Necessary conditions for the quality of plastering

In order to get quality protective covering It is necessary to use plaster compositions that meet the following characteristics:

• Increased adhesion with foam concrete products;
• Resistance to temperature fluctuations;
• Durability and strength;
• Hydrophobic properties;
• Excellent vapor permeability.

Attention: These properties are possessed by plaster mixtures that are designed specifically for finishing work on foam concrete surfaces.

For convenience, packages with such compositions have a special marking indicating the possibility of use on surfaces with a cellular structure. The price of special mixtures, as a rule, is higher than that of classical solutions, which is compensated by the end result - obtaining a high-quality coating. There is also an instruction, which indicates whether the coating is intended for external or internal surfaces.

Work will require:

• level;
• self-tapping screws;
• ground solution;
• roller;
• Trowel;
• Profile or board;
• Rules.

Surface preparation

The plastering of foam blocks begins with the preparation of the plane and the determination of the level of application of the layer. All the work can be done with your own hands, you can see it in the photo.

• We take the fishing line and stretch the walls diagonally. We apply a level and you can immediately see which layer needs to be applied.
• If the layer is more than five cm, then you should think about leveling the plane with drywall.
• With special care, you need to monitor the absence of oil stains on the surface. When they are found, it is necessary to apply clay to the spots and remove it after drying, thus eliminating unpleasant finds. In case of failure, the stain is completely cut down, and the hole is sealed with a solution.
• A high-quality coating involves the use of a deep penetration primer.
• For smooth plastering, it is necessary to install beacons or use a reinforcing mesh.
• The surface of the wall must be sprayed with water. The plaster solution is applied with a trowel, throwing it in small quantities on the walls.
• If your layer is up to one cm, then you can apply the composition immediately to the plane. If more, then it will be necessary to make the reinforcement of the plane and this will make the connection the most reliable and durable.

Step-by-step scheme for plastering blocks of foam concrete

Attention: In the case of self-preparation of the plaster mixture, stains on the walls and various technological errors in the future are possible. Therefore, the proportions must be maintained and the mass should be made homogeneous.

So:

• Your choice must be stopped on plaster mixtures with high adhesion. As practice has shown, in addition to specially designed compositions, gypsum mortars performed excellently.
• After filling the entire area with plaster, it is necessary to level the surface using the rule, while removing the excess and adding the missing volume to the empty areas.
• To obtain even corners, it is necessary to set the mounting profile or board in them using the building level.
• The mixture must be applied along the installed fixture, and after drying, carefully remove.
• Excess solution must be removed after it has dried slightly, in which case it is easier to correct it, since it does not “float”. However, it is necessary not to let the mixture dry completely, since it will be almost impossible to correct irregularities in such a situation.
• Complete drying of the wall surface is completed by stripping the rule and cleaning the frozen lumps of the mixture. Then proceed to finishing finishing work.

You now understand how to plaster foam blocks and can do this work yourself. The most important thing is not to rush and choose the right composition.

Of course, a protective coating must be applied to the wall of foam concrete materials. Dust in the air settles on the surface of the building material, and atmospheric precipitation also negatively affects. As a result, the product, which is in an unfavorable environment, begins to change color, which is not the most in the best way affects the appearance of the building.

However, this result cannot be attributed to the biggest trouble. Much more undesirable is the penetration of water into the porous structure of the material, which has a bad effect on the internal climate of the building. Blackouts, dampness and mold may also appear, but already on internal walls. That is why plastering of walls from foam blocks outside the house is necessary. It should be made of materials that allow air vapor to pass well to the outside.

Plastering foam block walls on the outside is the best solution, but you should be aware that concrete wall there is poor adhesion with cement-sand and lime plaster. It simply does not stick to the surface as it should. You will need a special plaster, which is commercially available. Experts recommend buying already ready mix rather than do your own cooking. The material is produced taking into account advanced adhesive properties, which are unlikely to "repeat" the product prepared by oneself.

The composition of the solution includes gypsum, and you can work with the mixture in different conditions. Also, plastering walls from foam blocks from the outside will allow:

• Ennoble appearance buildings;
• Protects the material from moisture;
• Will give vapor-permeable characteristics;
• Prevent the negative impact of temperature changes;
• Increase the thermal insulation performance for the house;
• It will prevent shrinkage of the structure, which is possible due to the ingress of dust and carbon dioxide on the walls.

This can be plastering the walls of a garage outside on foam blocks, a private house and any other building from this building material.

Before you plaster walls from foam blocks outside, you need to know about the lines for the production of blocks. They can only be used when at least a month has passed. This precautionary measure must be observed, since cracks may appear on the unaged material, which will further lead to deformation of the coating.

To carry out the work you will need:

• Container for preparation of the composition;
• Primer;
• Level;
• Grid;
• Metal brush;
• Nails, dowels;
• Drill;
• Spatula, brushes;
• Knife, plumb;
• Chisel.

It will be good if there was a note on the container with a primer and on the package with plaster that the product is intended for foam concrete. Then, when purchasing this product, you can not worry about the most effective grip.

Just like working with any other surface, plastering walls from foam blocks outside the house needs to be pre-cleaned from dust, debris, stains. Use a metal brush to help make cleaning more thorough. It will not hurt the possibility of using a drill for these purposes, where you can attach the nozzle.

The next stage is a primer, which will be applied in several layers to carefully cover deformations and improve adhesion. The second layer is applied after the first one dries.

Do not underestimate the process of priming the surface. It depends on him how well the applied material will hold.

After the walls are prepared, you can start mixing the mixture. You can do this manually, or you can use a drill and a special nozzle. In this case, the composition will be more homogeneous, without lumps.

Since plastering exterior walls made of foam blocks is not much more difficult than working with other surfaces, of course, with proper experience, there will be no difficulties for you here either.

• To apply the first layer of material, you will need a spatula. Put the required amount of mortar on it and apply it on the wall. It is necessary to act carefully, moving from the bottom up.
• Foam concrete has a cellular structure, so discard too thick a layer of interlayer. Carefully smear the product, which as a result should reach no more than 10 mm;
• After drying the first layer of material, it is necessary to use a reinforced mesh in order to enhance the strength characteristics of the structure. The material must be well stretched so that it fits well to the surface. For a thick plaster layer, a metal product is suitable, and in other cases it will be possible to get by with nylon. It is fixed with nails or dowels;
• Then you should re-plaster the wall, and wait until it dries completely, then apply a primer;
• When the result of the work is completely dry, it will be possible to start performing decorative work. You can paint the walls with paint, but it must be indicated that it is suitable for this particular type of material.

Materials with a silicate or silicone composition are best suited, due to their vapor permeability. If you have any doubts, it is best to consult a specialist.

We think that at this stage it became clear how to plaster the outer walls of foam blocks.

Before you plaster a wall of foam blocks from the outside, familiarize yourself with a number of technology features.

Before proceeding with the application of the solution, the installation of beacons will be required. These elements will help you get a smooth surface in the process.

It is important to remember what temperature is acceptable for outdoor work. For example, you have plans to plaster the walls of the garage on the outside of the foam blocks. The temperature outside should be between +5 and +30. If you still have to work on a hot day, it is recommended to treat the building material with water from a spray bottle.

You must clearly decide how to plaster the walls of foam blocks from the outside. We have already mentioned that he has too smooth surface, which, it would seem, is good, since you can not level the surface, but, unfortunately, mortar does not adhere to it.

To increase adhesion, a primer or special concrete contact is used. Such compounds are applied and dry for about a day, and are partially absorbed into the material, and partially solidify on the surface, creating the layer necessary for adhesion.

A mesh is also suitable, thanks to which there is an additional fixation of the plaster. Shouldn't be ignored preparatory work. This is actually a very important step that will ensure long lasting results and prevent delamination, cracks and other defects.

The implementation of plastering foam block walls occurs only after the work on thermal insulation. The material used for this is good insulation, but at the same time, the temperature changing at the joints can lead to the appearance of condensate, which will not have the best effect on the plaster. It is for this that it is worth monitoring the applied layers of the product. Strict relationships between the inner and outer layers must be observed, where the first must be 2 times smaller.

From all of the above, we can conclude that the work should take place according to the instructions, taking into account a number of rules. In addition, you need to pay attention to the packaging with the compositions, where the manufacturers prescribe recommendations.

How to plaster a wall of foam blocks outside with your own hands: video