Applying the bark beetle to the gas block. Internal plaster of aerated concrete walls: how to select and apply a solution

Correctly plastered walls are a guarantee quality construction at home. Many people want to know how the internal plastering of aerated concrete walls should be carried out. The article will tell you all the nuances and sequence of decorative wall plaster.

Aerated concrete blocks are most often used in the construction of low-rise buildings.

Their main characteristics are presented in the table:

In the manufacture of aerated concrete blocks, aluminum powder is added to the solution, which acts as a gas generator. This creates an open cellular structure, which increases the vapor permeability of the blocks. Such characteristics must be taken into account when plastering aerated concrete inside or outside the house.

Plastering of aerated concrete should be started with inside building, and then its facade. This is due to the fact that the water used in "wet works" will go out through the blocks and the available ventilation.

Water vapor at negative temperatures the environment will condense inside the walls of the house and on the border of blocks with exterior decoration (see. Exterior decoration of a house made of aerated concrete is a responsible business). When frozen, moisture will lead to inevitable cracking of the plaster layer, and then peeling it off.

Advice: It is necessary to perform plastering of aerated concrete walls first inside the building.

Types of plaster

Internal decorative plaster for aerated concrete walls can be:

Vapor permeable... It includes mixtures made on a gypsum basis. The best option is the Aegis TM35 plaster mix, which includes lime.

The mixture has a minimum weight, sufficiently high adhesion properties, good strength of the hardened coating layer.

Vapor barrier... Differs in the presence of a large number of polymer impurities. It includes: plastic decorative interior plaster and ordinary cement-sand mixture without additives.

The best option than plastering the gas block inside is the usual inexpensive gypsum mixture used in conjunction with a vapor barrier primer.

Tip: To reduce the vapor permeability of a 10 mm thick plaster layer, the walls should be primed at least three times.

Plastering tools

The service life of the coating itself depends on the quality of the preparatory work. To do this, first of all, the necessary tool is purchased (see Tool for plastering walls: what is needed for work). Its main types are shown in the photo.

To plaster the walls with your own hands you will need:

A plastering hammer with a pick or a small hatchet. With their help, protruding parts on the wall are knocked off, notches are made that increase the adhesion area of the plaster mixture to the surface.
Maklovitsa. This is a large brush used to coat walls with a deep penetrating primer to bond the surface layer to the wall and increase wall adhesion.
Plumb line. Serves for hanging the verticality and determining the flatness of the plastered wall. Plumb lines help to build a "spider" that allows you to install beacons for applying plaster on a given plane.
Building level.
Square. Its difference from the joinery is in the size and the presence of a retractable rail.
Strong nylon threads - for making a "spider".
Perforator, hacksaw, chisel, nippers, metal scissors.

In order for the interior decoration of the plastered walls to be of better quality, you will also need such basic tools for applying plaster as:

A bucket with a volume of up to 1 liter. With its help, it is quite convenient to throw a solution of any consistency on the surface to be plastered, it is good for them to measure required amount ingredients used to prepare the plaster mixture in small quantities.
Plastering trowel. With this tool, the solution is thrown into those places where there is little of it.
Falcon. It is a rectangle made of wood or metal measuring 40 x 40 centimeters with a handle perpendicular to the main plane. A small amount of solution is brought up with the tool to correct small imperfections.

Rule. This is a flat wooden or aluminum lath, for aligning the mortar thrown over the beacons, for eyelining the existing internal corners. The length of the rule is from 0.5 to 3 meters. When working, the tool is installed with two ends on neighboring beacons, and then it is pulled along them, removing excess solution. At the same time, additional portions are added to places with an insufficient amount of solution, providing an even layer on the surface.

Half-eater. It is a polished wooden lath 40 to 80 centimeters long and up to 15 centimeters wide, with a handle. The tool is used to level the plastered surface after the solution has lost water, but has not yet hardened.

Steel trowel. It is a polished metal plate with a handle and is used to perform an operation called "ironing".

In addition to these main hand tools used for plastering large areas machine plaster... In this case, the entire process, from the preparation of the mixture to its spraying, is carried out by a machine under high pressure. All other work on leveling the plaster is done manually.

The advantage of this method when applying the plaster is that the coating is driven into the wall under pressure, ensuring that it is firmly attached to the wall.

Preparing the walls

To get high-quality plaster of walls inside the house, you need to perform some preparatory operations:

Produced visual inspection walls for defects after the blocks have been laid.
The gaps left are sealed with repair mortar. For this, it is better to use special glue.

The surface is leveled.
After drying, the walls are swept with a stiff plastic brush to remove dust and dried mortar fragments.
The surface is primed with a deep penetration compound. For this, rollers, brushes, conventional garden sprayers or compressor units are used.

After drying, the next coat of primer is applied.
Tile glue is diluted to the consistency of thick sour cream, which is indicated by the instruction for its operation.
Painting room is being prepared plaster mesh by the height of the room.
Glue is poured onto the wall from the bottom to the ceiling in a strip slightly larger than the width of the reinforcing mesh, with a layer thickness of about 5 millimeters.
A strip of fiberglass mesh is glued, starting from the top, onto the wall and slightly fixed by pressing it into the solution to the very bottom, for reliability.

With a notched trowel from the ceiling, the mesh is pressed into the glue layer with force so that the material is completely drowned in the solution. The excess glue is squeezed out.
The direction of movement of the trowel can be chaotic at first, gradually changing to horizontal grooves along the entire wall. This will provide excellent wall reinforcement.
Along the edge of the wall section, you can leave an even strip of glue to overlap the next fiberglass mesh. The overlap width must be at least 100 millimeters.
As a result, the entire wall is covered in this way, on which the glue layer has horizontal grooves. This ensures an excellent connection of any plaster with a high coating strength.

Application of textured and structural plaster

Internal textured decorative plaster can be:

Lamb... It contains stone grains different sizes... After application to a mineral base, the surface becomes rough and uniform in grain.

Fur coat... After application, a roughness is obtained on the surface in the form of a slight "hairiness", the main component of this mixture is cement.

Bark beetle... It is a composite decorative plaster for interior surfaces filled with small stones. After application, a furrowed texture is formed on the surface, resembling pitted wood in appearance (see Textured plaster Bark beetle: characteristic features of the material).

Decorative plaster is applied in several layers.
A small portion of the mixture is taken with a spatula and evenly distributed over the trowel.
The tool is placed on the surface at an angle of approximately 30 ° and the compound is applied to the wall.

Advice. You cannot start work immediately on a very large area. It is worth experimenting on a small area, otherwise the plaster will dry out and the result will not be satisfactory.

Textured plaster is a very malleable material that can take any shape if necessary. In this case, you can use a traditional paint roller or a regular sponge.
The surface of the wall is processed with a spatula.

The necessary pattern is formed along the wall.

Venetian plaster application

It is quite difficult to apply such a coating yourself. It's worth previewing the video in this article.

The plaster layer is applied in the following sequence:

A thin layer of coating is applied to the surface, trying to create a certain pattern.
The layer should dry for about an hour.
The dried surface is lightly sanded with a large trowel to remove minor imperfections.
Smoothes to level the coating.
The second layer is applied in the same manner as the first.
The last layer of the decorative coating is applied with a spatula, which should be translucent and thin enough to give it greater depth.
The work is postponed for 30 minutes to dry the material.
The wall is smoothed with a spatula.

This is how Venetian plaster is applied in a dry room.

Internal plaster with cement and sand differs from Venetian plaster in simpler application. It is enough to prepare the necessary tool, observe several rules on the technology of applying the solution to the surface. And after the end of the work, rinse all the tools without leaving any traces of the solution on it. Decorative plaster on the walls made of aerated concrete blocks creates an original and beautiful finish.

Aerated concrete is gaining more and more popularity as construction material... And this is not surprising. Large block sizes can significantly reduce construction time, and the cellular structure retains heat, allowing you to reduce heating costs. But this material requires serious moisture protection.

Aluminum powder is added to the basic solution from which aerated concrete is made. At one stage in the process, this component releases gas, forming air-filled cells. 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. The moisture accumulated in the autumn or spring time will also quickly go away under the influence of sunlight. But in winter this factor will be destructive. And over time, small cracks will appear on the walls, and then delamination.

In addition, aerated concrete has the following characteristics:

Low rates of thermal conductivity.
The 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 steam permeability, which makes homes comfortable, since internal vapors quickly escape to the outside, and do not accumulate in the premises.
High rates of moisture absorption, which forces the house to be faced with moisture-repellent materials.

When is it better to plaster aerated concrete walls?

Most often, plastering is chosen for finishing aerated block walls. But you should choose the right time to complete the work, as well as the right composition. We will deal with the type of plaster for the facade a little lower, and now we will consider the time for finishing work.

Do not plaster immediately after construction. The walls are given time to dry completely and shrink. It is enough to wait a year. If this is not done, cracks will appear on the finish.
They select the warm season, when the night temperature does not go 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 out.
To protect the walls in winter from moisture and frost, 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.
Plastic wrap is also suitable as a barrier for unlined walls.

Is it necessary to pre-insulate the outside?

As mentioned above, walls made of this building material retain heat well. Therefore, with a competent calculation of 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 building is being erected.

You should not make the walls too thin so that they need to be additionally insulated, since it will be difficult to choose insulation. The aerated concrete structure has high steam permeability indicators, and if the thermal insulation does not cope with this task, then condensate will appear with outside walls. This will lead to the destruction of aerated concrete and insulation.

If it is already necessary to carry out insulation, then choose a material that can pass steam from indoor spaces... According to the rules prescribed in State Acts, the steam throughput is from interior walls to the exterior finish should increase. Only in this case it will be comfortable to stay in the rooms, and mold and mildew will never settle on the walls.

Which mixtures are better for using?

When choosing a mixture for plastering gas-block walls, the following properties are noted:

Moisture repelling.
Good adhesion to the substrate.
Resistant to low temperatures.
Elasticity.
Decorativeness.

The assortment of building stores offers several types of plaster mixes. 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 a thin layer of lightweight plaster. It is used only for interior work. It is not worth it with 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:

The mixture adheres well to the substrate.
Apply in a thin layer.
The vapor permeability of the solution increases.
The finish is durable.
Inert to the appearance of mold fungi.
Affordable low cost.

There are, of course, several disadvantages:

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

Acrylic

This option is used for decorative facade decoration of gas-block houses. It is applied in a thin layer, but it has a number of advantages:

durable;
elastic;
resistant to low temperatures;
the color retains its original brightness for a long time;
helps to strengthen the base in places where the load is increased;
repels moisture.

In spite of a large number of advantages, there are such disadvantages that cause great 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 being built in the house.
The acrylic compound is highly flammable, so it is not suitable for wall areas near a fire.
High price.

Silicate

Liquid glass-based compositions are excellent for both interior and exterior decoration. Such plaster is sold only in finished form. Stir thoroughly before use. The main advantages are:

vapor permeability;
moisture-repellent properties;
a large selection of textures;
affordable price.

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

Dirt and dust accumulate on the surface of the finish, which reduces the attractiveness of the coating.
A small selection of colors and shades.

Silicone

This option is made on the basis of silicone emulsions or resins. It is great for decorating facade walls. It has such undeniable advantages:

Hydrophobic (repels moisture, practically does not get wet).
Vapor permeability.
It is convenient to apply, therefore it is suitable for those who decide to do everything with their own hands.
Plastic.
Crack resistant.
It retains its original color for a long time.
Easily cleaned from dust and dirt.

Of the shortcomings, only the price is noted, which is an order of magnitude higher than the 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 version of plaster mixes, which is perfect for various substrates. But aerated concrete does not withstand the use of a cement-sand mixture. Everything is due to the lack of certain characteristics.

Is a cement mortar suitable for these purposes?

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

Low steam permeability.
The solution contains a lot of moisture. The gas block quickly absorbs water and then gives it away for a long time, which increases the term of work. In addition, cement plaster with rapid evaporation of moisture loses its strength, as a result of which cracks appear.
Aerated concrete has smooth surface, and the cement-sand mixture has low adhesion rates. Therefore, the solution does not adhere well to the base and can slip during operation. To avoid this, the walls are covered with a primer for aerated concrete, but this does not always help.

Add lime to the usual solution.
Mix a special mixture for aerated block and cement mortar in a 1x1 ratio.

And what about the glue for porous concrete?

A special adhesive 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 in a thin layer.
Designed for grouting.
Does not allow steam to pass through. Which leads to the appearance of condensation on the inner walls, and then mold.

Such material is used only for its intended purpose.

Interior decoration

It is customary to perform internal wall alignment with plaster first. Thus, moisture that is absorbed from the solution will quickly leave the thickness of the wall. on internal walls made of aerated concrete do not differ much from plastering other surfaces. They adhere to this plan:

Preparation of the base. Removal of bumps and other irregularities. It is better to do this again when the walls are being erected, since in the future this leads to an increase in the waste of the solution.
Padding. It is advisable to choose a deep penetration soil, especially for rooms with high humidity, for example, a bathroom or kitchen. Never dilute the primer with water. This reduces the quality of the soil layer.
- help to control the thickness of the applied layer. The distance between elements is slightly less than the length of the rule.
Spatter or throw on the first coat. The solution should not reach the top edge of the beacons.
Forming corners using a perforated profile with a reinforcing mesh.
Application of the second layer. The thickness will be narrower. The solution is also thrown, but immediately leveled out by the rule. At the same stage, beacons are removed.

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

Outdoor

After the internal work is completed, they begin to refine the facade. Be sure to check the dryness of the aerated concrete. Plaster applied to wet walls may flake off. It is also important to choose the weather conditions:

The optimum temperature is from +5 to +25 degrees Celsius.
Lack of wind.
Air humidity not 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 it is not necessary to level the walls additionally. But in the process of laying, 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 a solution and left to dry completely. Therefore, the treated areas are rubbed with a metal float in order to remove the protruding solution. Dust is removed with a brush or damp cloth, but make sure that the material is not too wet.

Padding

For priming the facade walls, deep penetration compounds are chosen. They create a strong film that prevents moisture absorption, but at the same time the steam passes through quietly. Also, an additional layer will increase the adhesion of the plaster and the base.

Apply the primer in several layers, depending on climatic conditions terrain. 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 processed with a small brush.

Plaster 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 alkali resistant.

Reinforcement and plastering are performed simultaneously, following this plan:

Cutting the mesh into strips.
Preparation of the solution, according to the instructions indicated on the package, if a dry mixture was purchased. The finished solution is simply mixed so that all components are evenly distributed.
A solution is collected on a wide spatula and evenly distributed over the surface, about 0.5 cm thick.
A special perforated profile with a reinforcing mesh is applied to the corner. The mesh is smoothed over the applied solution.
Then separate pieces of mesh are laid. Be sure to make a whip of 5-10 cm. Reinforcement is smoothed by immersing in a solution. In places where it looks through, add a little mixture and smoothen again.
The surface is treated in small areas with the expectation of full use of the finished solution.

After the entire facade is plastered, it is left to dry completely. There should be no flaws and protruding reinforcement on the surface.

Finishing layer

Choose as a topcoat 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, they work especially carefully, since the remaining flaws will be noticeable.

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

Aerated concrete is a cellular type of concrete, has a porous structure. Therefore, buildings made of aerated concrete blocks easily absorb moisture. Accordingly, for their greater resistance to bad weather, the material requires protection. Among the most common methods is the use of plaster. Let us consider in more detail the features of plastering gas blocks, where to start, what tools will be required, what finishing technologies exist in this way.

Aerated concrete absorbs moisture very well, so you need to protect it

When to start decorating aerated concrete walls

The main distinguishing feature of aerated concrete is its increased hygroscopicity. Moreover, when the structure gets wet, when the temperature is above zero, it will be possible to avoid negative consequences - it will simply dry out, everything will be fine, but when water gets into the pores of the stone in winter, it freezes, accordingly, it expands, cracks may appear.

Given this, it would seem that the earlier the walls are plastered, the better. But this approach is wrong. Ideally, these activities should be carried out for the next season, when the surfaces are completely dry after laying. Drying time depends on the type of mortar used for laying. For example, a seam made with a concrete-sand mixture will dry longer than the one where the glue mixture was used, since it turns out to be much thicker.

Plastering is recommended for the next season.

Another condition for decorating walls made of aerated concrete, recommended to be observed in order to achieve a high-quality result, is the need to do everything in warm weather. Experts call the optimal time March-October, when the air temperature is above zero. If it is not possible to do this, it is necessary at least to cover the stone with a primer, cover it with plastic wrap, so that it will stand without losing its properties until the moment of complete finishing. The most effective water absorption will be reduced by deep penetration primer.

But the opportunity to postpone Finishing work sometimes absent - they need to be carried out immediately after the completion of the construction of the walls of the building. Here, experts recommend paying particular attention to the composition of the solution. It must have good plasticity, vapor permeability, then moisture can freely come out.

If you need to plaster immediately, then you need to carefully select the material

Which side to start finishing the gas-block building

There are three options for where to start covering aerated concrete wall blocks. Each has its own characteristics, and only one is considered correct. Specifically, you can start:

outside;
from the inside;
simultaneously from both sides.

Experienced builders recommend starting plastering outside only when the dwelling is located near water bodies. The primary task here is to protect the aerated concrete from water and wind. Under other circumstances, the method of processing from the outside is not suitable - if you plaster the stone from the outside, all the moisture will go inside the house, which may cause cracks, and the drying process of the joints at the end of the masonry will be significantly delayed. In addition, the stone itself may begin to deteriorate. Plastering walls made of aerated concrete indoors will help to avoid the above problems - this method is considered the most preferable due to its effectiveness. The third method is considered the most unpopular way of decorating aerated concrete walls - despite the good vapor permeability properties, having “blocked” moisture from both sides, it will have nowhere to go, which sooner or later will lead to the separation of the finishing mixture from the block itself, and later even the destruction of the latter.

Plastering only needs to be done on one side

Sequence of work

Plastering of aerated concrete blocks contains three stages. Before plastering aerated concrete, apply a special primer designed for building materials that absorb moisture well with a brush or roller. The greatest efficiency is achieved by applying the solution evenly, that is, there should be no dry places. After completing this stage, the primer should be absorbed and dry.

At the second stage, a special reinforced mesh resistant to alkaline components. The mesh is fixed at a certain distance from the stone - there should be free space between them.

The final, third, stage is directly plastering the walls from aerated concrete. Here it is important to choose materials whose vapor permeability properties are higher than those of the aerated concrete itself. To increase the service life of the surface, while maintaining its attractive appearance, you can, after a year, by covering it with a water repellent.

The material for plaster should be chosen with a higher vapor permeability than aerated concrete

How to plaster - requirements, nuances

Aerated concrete plaster will become of the highest quality, it will not have to be done with a new one in a short time, if the composition of the mixture meets certain requirements, and the packaging contains special markings. Among other things, it must be characterized by:

resistance to cracking, drying, fading;
increased ductility without sacrificing strength;
good adhesion to porous concrete types;
water-repellent properties;
high level of vapor permeability.

It is especially important to meet these criteria when used outside the building.

Even considering the large number different types of modern plaster solutions, these characteristics are possessed by units, therefore, most often when working on processing aerated concrete, the following are used.

Silicone plaster is perfect for finishing aerated concrete outside.

Silicone plaster for aerated concrete has the most advantages. It is resistant to adverse weather conditions, has good vapor permeability, water repellency, and is easy to apply. This type has no disadvantages in operation, except for its high cost, which is nevertheless compensated by the long service life of the coating.

The second place belongs to silicate plaster for aerated concrete, characterized by a suitable level of vapor permeability, low water absorption. The main disadvantages are small color palette plus loss of original attractiveness appearance silicate in case of dust ingress.

In third place is cement-lime plaster. She also has the necessary qualities to cover this type of building.

Aerated concrete plaster can be carried out with a cement-based mixture

Often, gypsum mixture is also used in such houses. Its advantages: it dries quickly, subsidence is excluded, there is no need to apply a finishing layer of plaster, in addition, you can make the surface as smooth as possible. However, the solution has its drawbacks. This includes the average characteristics of vapor permeability, susceptibility to rapid wetting from precipitation, in addition, stains may appear during its operation.

In addition, acrylic solutions are used for processing. Their rather significant advantage is strength, but one must also remember about the disadvantages - low refractoriness, which is why it is used only in certain rooms, with a relatively low level of vapor permeability. To prevent condensation from accumulating in the pores of aerated concrete, experts recommend using additional ventilation or internal waterproofing.

Having studied the characteristics of all the materials presented, everyone can independently choose how to plaster aerated concrete.

Aerated concrete finishing scheme

Used tools

Plastering of aerated concrete walls is carried out using tools used in the treatment of other surfaces. Beating off the protruding parts of the walls, making them more smooth, installing notches where they are needed, is done with a plaster hammer or hatchet. The deep penetration primer is applied with a special brush (brush). You will also need a plumb line (it helps to install beacons to cover the desired surface with a solution), a building level, a square, metal scissors, a puncher, a hacksaw, and other standard tools. There are several options for lighthouses. The first is to purchase specialized metal beacons in a hardware store, fortunately, their choice is now quite wide.

Before starting work, you should prepare all necessary tools

The second, "old-fashioned", method is to use the means at hand: even pieces of wood, pipe cuttings, and other suitable "details". Thanks to the beacons, the plane is perfectly flat, the corners are correct. The listed tools will come in handy if the plastering of aerated concrete walls is done manually.

Faster, even application can provide special equipment... The method is more costly financially, but this is fully compensated by the quality of the final result: thanks to the implementation of plastering under pressure, the bond of the mortar to the surface of aerated concrete is quite strong.

Machine plastering is slightly more expensive

Coating technology

The technology of wall decoration with plaster for aerated concrete is quite simple - it is performed in four steps:

the preparatory stage, where, before plastering aerated concrete, it is leveled, thus reducing the consumption of the solution;
padding;
covering the walls of aerated concrete with a thin layer of plaster, which will further act as a base when fixing the reinforced mesh;
mesh reinforcement (prevents cracking).

For reinforcement, a metal or fiberglass mesh is used. Moreover, when installing it, special attention should be paid to windows and doors - places where the most significant load.

Having fixed the mesh, the plane is covered with a finishing layer of plaster, and when the coating dries up, the so-called grout is performed, that is, the surface is eliminated from irregularities, roughness, and other minor defects.

Before plastering aerated concrete, level the wall

Features of finishing aerated concrete

Starting to cover aerated concrete with plaster, you should take into account the features of this material. First of all, experts recommend avoiding the traditional combination of cement and sand. The corresponding coating can crack over time, fall off, and it also contains a lot of water, which has a destructive effect on the walls themselves.

When plastering gas blocks, a prerequisite is the intended purpose of all funds specifically for cellular material.

Experts recommend not to use cement mixtures for finishing aerated concrete

It is important to start work on the external facing of the facade, when all the "wet" internal work has already been completed, then it is possible to avoid the formation of condensation inside the walls. Moreover, the thickness of the plaster layer inside the building must be twice as large as the outer one, otherwise water vapor will remain inside the blocks, they will dampen. This is the only difference between carrying out these works inside and outside - the technology itself remains unchanged.

If you take into account the recommendations of experts, aerated concrete will serve you for a long time

Thus, we see: with all its advantages, the building material is still quite picky, requires a special attitude. And in order for it to retain its useful properties to the maximum, a number of measures must be taken. But observing the above recommendations, it will prove itself as a very reliable material, it will last a long time, and the home will be cozy and comfortable.

Video: Plastering aerated concrete, preparation of the base

Video: Aerated concrete putty and plaster

Renovation inside or outside the premises will not do without plastering walls and other surfaces. At the design stage of work you need to familiarize yourself with the features of the plaster, which are divided into types, they differ in characteristics and price. The correctly chosen type of finishing material is half the battle, because characteristics of mixtures can differ significantly among themselves, and what is ideal for one type of room may be completely unacceptable for another.

Some features of plaster

Plaster is a mixture that is used for surface treatment as a rough finish. What are the functions of the material? Plaster can be used to level walls, repair cracks and other defects. Itself the structure of this solution is a coarse mixture, therefore, after drying, the surface will have rough surface... These effects can be easily eliminated in the future.

Walls can be plastered of almost any type, concrete and wooden structures will be protected from harmful effects environmental factors. Various techniques and materials are used for plastering aerated concrete walls. Trends in the field of construction are developing in such a way that such building material as aerated concrete is gaining more and more popularity. It has many advantages over concrete and brick construction.

The building, erected from aerated concrete, has increased energy-saving properties. This material is much lighter than traditional counterparts, due to this fact, it is possible to reduce the cost of arranging the foundation and the construction time is significantly reduced. What kind of plaster is better to plaster the walls of aerated concrete blocks?

How to plaster aerated concrete walls?

One of the ways to decorate aerated concrete walls is plastering... For plastering walls made of cement-sand type blocks, this is the best option. As for the process of applying the finishing layer itself, if you wish, you can apply it directly to the wall. The same can be done with brick walls... However, this may pose some difficulties.

The brick is small, therefore seams between bricks serve as a connecting element when applying plaster. In the case of aerated concrete, the situation is somewhat different, because aerated concrete itself is large. This problem can be solved in several ways. Let's consider the main ones that are often used in practice.

Walls can be plastered both inside and outside the room. Both finishes have some specific features. When choosing a plaster, it is best to select the one with the maximum adhesion coefficient. This is to ensure the quality of adhesion of materials.

Preparatory work

Before applying a layer of plaster, the walls are prepared from aerated concrete, this is necessary in order to ensure adhesion of materials. How is this done and what does this stage of surface finishing include?

First, you need pay attention to the seams between aerated concrete, they need to be well sealed, approximately 4 - 5 mm... The wall is leveled, and all defects that may occur, dust and other microelements that reduce the quality of adhesion of materials are cleaned out. Sandpaper can be used to clean the surface to help sand the blocks more thoroughly.

How to apply mesh correctly when plastering walls?

If you decide to use the third method of surface finishing, then you need to know what is used in this galvanized mesh... It is more durable, reliable and does not rust. As for the size of the grid cells, you should pay attention to the one with small cells. After carrying out the preparatory work, it will be necessary to attach the mesh directly to the wall. This must be done with ordinary nails. They are hammered into the wall first by one third, after which the nail is bent, fixes the mesh.

Particular attention should be paid to the edges of such a cross, they usually stick out, before applying the plaster, all the edges should be folded, then they will not stick out from under the plaster.

When the mesh is secured it is necessary to start applying the first layer of plaster. This is done in what is known as "Splash", it is mainly used to fill mesh cells with a solution. After it, several more layers of plaster will follow. This will necessarily be a primer layer, which must be kneaded by adding slag sand to the solution. The final layer will be the final layer; fine sand must be used to prepare the solution for it.

All layers of plaster can be apply with incomplete drying of the previous layer... This will shorten the time without compromising the strength and quality of the finishing layer.

Mortar for plastering walls can be purchased ready-made, it is sold in a dry state. To prepare the mixture, you just need to add water. But, you can also prepare a cement-sand mortar yourself. In this case do not skimp on the quality of the cement itself, since the water-repellency of the plaster will suffer as a result. When plastering walls, a lot of tasks and requirements are solved, such as thermal insulation characteristics of the surface, water resistance, noise insulation, and so on.

Aerated concrete blocks are incredibly in demand today - and not only in private construction, but also in the construction of frame-block multi-storey buildings. The products are compact, lightweight, easy to assemble, which allows a person to build a warm and inexpensive home with their own hands.

However, raising the walls and bringing them under the roof is not all. You need to know exactly how to plaster aerated concrete inside the house, and understand on what basis the internal plaster is generally selected. These are the questions that have become the topic of this article.

Both aerated concrete and gas silicate concrete belong to the category of cellular concrete. There is an opinion that they are one and the same, but there is still some difference between them.

In both materials, there is a combination of two cement-lime binders. However, their percentage is different, resulting in a material with completely different strength characteristics.

Leveling coatings for aerated concrete

Aerated concrete contains up to 60% of cement, and the rest is lime and sand. In gas silicate products, there is only 14% of cement, almost twice as much lime, and many times more sand. It is clear that if there is so little cement, then the strength of the products is no longer the same. In general, aerated concrete is no longer a structural material, but a heat-insulating material.

Perhaps now you have a question: "What does the internal plaster of the walls have to do with it?" And despite the fact that it is selected depending on the type of base, and in order not to have problems with the coating later, you need to know exactly what and with what can be combined. The characteristics of the binder are decisive here.

Note! Cement, or rather products and solutions based on it, always has greater strength than lime and gypsum. When creating multi-layer screeds, the following principle must be observed: the base must always be more durable than the coating - otherwise, it will inevitably peel off.

From the above, it is not difficult to conclude: if there is no or almost no cement in the blocks, then the internal plaster of the walls, and even more so the external one, cannot be produced, for example, with a cement-sand mortar (see Optimal ratio of cement and sand for plaster ). Applicable to gas blocks, it can be used, since they have a high percentage of cement, and the wall surface has sufficient strength.

You can even use non-special purchased mixtures, one of which we see in the photo, but knead the solution yourself. You just need to keep in mind that the plaster should not be done as for heavy concrete or clay brick - in proportions of 1: 3, when a mortar of the M150 brand is obtained.

Plastering of internal walls from aerated concrete, performed with a solution of half the strength: M75. For its manufacture, take cement M400, and mix with sand 1: 5.

With an increase in the grade of cement, its amount in the solution should decrease to 1: 6, or even to 1: 6.7 - this is the arithmetic. Everything is done quite simply, and the lower price of self-mixed plaster will significantly save on finishing work.

How to plaster gas silicate

Now, as for the gas silicate wall, in which there is very little cement. Accordingly, such a plaster as for aerated concrete is not suitable for it. However, it is impossible to infinitely reduce the amount of the binder in the solution - you can only replace a part of it with another, less weak binder in strength.

IN gas silicate blocks there is a large percentage of lime, and it is most logical if it is also present in the plaster. That is, the most ideal option for plastering such walls would be lime-cement plaster. It is more difficult to make it yourself, since lime dough must be present in the solution.

It is much easier if the inside plaster of the house will be made with a commercially available mixture. And by the way, if it is suitable for gas silicate, then it is also suitable for aerated concrete (and not vice versa). Manufacturers often orient plaster mixes to both materials, which means that, in addition to cement, lime is also present in them.
Sometimes the instruction on the packaging says that the mixture can be used for all aerated concrete. This means that they can also be applied to walls made of foam concrete, which contain only cement from binders. Just keep in mind that there are cementless types of foam blocks made on the basis of lime.
Like gas silicate, this material is also more of a heater than a structural material. Foam blocks, in which there is no cement at all, are used for construction interior partitions... They can also be plastered, but only there should be no cement in the solution.

It should be noted that the best option for leveling walls made of gas and gas silicate blocks, lime foam blocks, as well as silicate bricks, are silicate plasters. But since they contain liquid glass, and they are very caustic, they are not used for living quarters - only in production workshops and on the facades of buildings.

Feasibility of using gypsum mixtures

Plastering inside a house with limestone surfaces can be done with gypsum or lime-gypsum mixture. In principle, they are suitable for all types of foundations, but there is one but, and it concerns walls built of cellular concrete.

Given their high vapor permeability, and a similar property of gypsum, it is not always advisable to use plaster based on it indoors:

Here it is already necessary to consider the structure of the wall decoration as a whole, and oddly enough, you need to focus on the option exterior decoration... For example, outside the aerated concrete walls will be monolithically lined with brick, clinker tiles, or stone, or plastered on expanded polystyrene.
Due to their poor vapor permeability, these materials will trap moisture in the thickness of the walls, preventing it from escaping. In this case, only cement plaster should be used inside, or a decorative coating should be provided that will become a barrier to steam.
For example: if it is paint, then alkyd; if wallpaper, then vinyl or cork. Yes, the same tile or stone, any cladding with insulation - all this will not allow porous walls to be saturated with moisture.
In what case can internal plastering of walls made of aerated concrete, or other cellular material, be performed with a gypsum mixture? There are only two options. The first is when the external walls are aligned with the base base with plasters with a high degree of vapor permeability: silicate, silicone, special for cellular concrete.
The second option is a ventilated facade. When there is an unobstructed outlet for steam and condensation from the outside of the wall, the internal plaster of the walls, like their finishing, can be done as you like. But note that if the facade is insulated, then the thermal insulation boards should be loose: soft mineral wool or the cheapest loose foam.

Let us also clarify this situation. Decorative plaster for interior decoration, is most often made on the basis of plaster. How to properly prepare a porous base when the use of gypsum mixtures is undesirable. With cement-based blocks, there is no problem.

In any case, the base before decorative plastering should be leveled as for wallpapering. Therefore, the walls should first be leveled with a cement compound, and when it dries, it can be applied and gypsum plaster decorative for interior decoration. You will learn more about this in the next chapter.

Internal plastering of aerated concrete

So, in our story, we came directly to the implementation of internal plastering work on aerated concrete walls. We will try to cover the most important nuances of this process, and for clarity, we suggest watching the video in this article.

The nuances of preparation

Porous surfaces are characterized by the strongest moisture absorption, which must be reduced by priming. It is produced more abundantly on aerated concrete walls than, for example, on brickwork. To do this, you need to take not just an adhesive primer, but a deep penetration composition.

Important! Primers are ready-made, but they are concentrated - that is, they are diluted with water in a proportion determined by the manufacturer, which must be observed. Do not think that if you apply undiluted primer, you can, for example, reduce the number of passes. The composition should be of normal concentration.

The first layer is applied abundantly, preferably with a spray gun. You can also take an ordinary garden sprayer for this purpose, with which trees are sprayed. After aerated concrete wall dries slightly after processing, another layer is applied, after which the surface should be completely dry.

Double impregnation significantly reduces the absorbency of the wall, but does not completely eliminate it. Yes, this is not necessary - otherwise how will the solution stick to the surface? The surface of the gas blocks is very smooth, and for the plaster, it is necessary to ensure good adhesion. It is impossible to make notches here, as on heavy concrete. How to get out of the situation?

How to make the plaster coating as durable as possible

After priming, task number two is surface reinforcement. This is necessary not only for the best adhesion of the layers, but also for the prevention of cracking.

This is especially important when the walls are built of gas silicate, which has five times less cement than gas blocks. The strength of such a base is rather weak, and plaster, even gypsum, will be more durable and will work to tear.

Your task is to create a strong interlayer between the subfloor and the plasterboard, which will give them the best adhesion. Therefore, no matter what type of plaster you use, the starting layer must be made with an adhesive mixture, which is intended for the installation of cellular blocks.

To create a reinforcing layer, ordinary tile glue is also suitable. Many craftsmen, due to the lower cost than the masonry mixture, prefer to use it. Why is an adhesive composition needed, and not just a plaster?

Note! The fact is that adhesives are always modified with polymer additives, which do not just adhere, but firmly glue the surfaces. The layer of glue is thin and durable; the fiberglass mesh is also embedded in it. It is not only an excellent base for plaster, but also reliably fixes blocks, preventing microcracks from appearing and expanding.

This approach to preparatory work is especially important when self-made mortars are used for plastering. In them, in contrast to the factory, specially designed for gas blocks, there are no improving modifying additives, as well as fiber reinforcing the plaster in the mass.

There are no words, factory mixes solve all problems, but due to their high cost, they are more often used for facades. On the internal plaster, which is not exposed to such influences as on the street, you can save money - only you need to do it wisely. If you do not want to have problems in the near future, the adhesive layer must be done in any case.
Installation of the mesh, in principle, is not necessary, and is carried out by craftsmen at the request of the owner of the house. But the customer should know that the creation of a reinforcing layer only improves the quality of both the plaster and the base - after all, no one knows what shrinkage processes will occur in the soil.
It is better to play it safe, and spend a little money on the net, than to incur expenses in the future. complete renovation... We especially advise you not to neglect the grid when the walls are being prepared for painting - after all, any crack on them will be immediately visible. Cracks are invisible under dense wallpaper or tiled cladding, but the task is not to hide them, but to prevent them from appearing.

There is nothing complicated in the installation of the grid, and in the video presented in our article, you will see it. The canvases are applied with an overlap on the freshly applied adhesive solution, and then pressed, combing with a notched trowel. The use of such a tool is very important, since thanks to it, scallops from the squeezed out solution remain on the surface of the mesh.
When they dry, you get a beautiful embossed surface on which you can apply any plaster. First, the mesh is pressed into the glue layer with chaotic movements, trying to press it as tightly as possible to the base. If you are going to carry out the usual leveling plastering on the walls, in the end, you need to do a horizontal comb.
This is necessary only so that the plaster, which in the next stage will be applied to this surface, does not slide off the wall. Well, for decorative plaster - if it will be used for interior wall decoration, the base should be smooth. In this case, the relief is not left, and the solution on the mesh, squeezed out with a notched trowel, is smoothed out.

When can you start plastering directly? Let's say right away that it is undesirable to do this right the next day.

Even if the surface appears dry, the cementitious adhesive has not yet gained sufficient strength. It is not scary if plaster is applied to it with gypsum. If it is a cement mortar, then the glue layer must be given at least five days - or preferably a week, to gain strength.

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