Insulating a house made of aerated concrete is not mandatory, but in some cases it is very desirable. In this article we will try to explain: why insulate aerated concrete; what to choose, polystyrene foam or mineral wool; what thickness of insulation to use; when to carry out insulation.

At first glance, it seems that there is only one reason - to save money on heating, but let's look at this in more detail.

Reasons for insulating aerated concrete:

1. Reduced heat loss through walls, as the thermal resistance of the wall increases, resulting in lower heating costs.
2. Closing cold bridges in walls, such as armored belts, lintels, thick seams. Not only do they cause heat to escape from the home faster, but they can also become wet areas in the home where mold can grow.
3. Increasing the durability of the building. External insulation of aerated concrete with a thickness of 100 mm or more transfers the dew point from the wall itself to the insulation, that is, freezing of moisture in aerated concrete will not occur, which will make the service life of aerated concrete much longer.

Is it profitable to insulate aerated concrete or not? If we consider the economic feasibility of insulation, then we need to find out the payback of insulation. That is, how long will it take for savings on heating to pay for the insulation itself?

If the payback period for insulation is more than 10-15 years, then there is no point in such insulation; it is more profitable to put money on deposit in a bank.

But there are also cases when insulation is very beneficial:

1. If gas and electricity are very expensive.
2. If the house is located in a cold region.
3. If the wall thickness is less than 300 mm.
4. If the walls are made of high-density aerated concrete D600 and higher.
5. If the walls have thick seams and many cold bridges.

To determine the thickness of the insulation, you need to find out what the required thermal resistance of the walls is needed for your region, and how long it will take for the insulation to pay for itself.

It happens that people insulate their houses with a thin layer of insulation of 40, 30 and even 20 millimeters. Which is a big mistake in terms of feasibility and payback. The thicker the insulation layer, the lower heating costs will be in the future.

It is worth understanding that the cost of glue, foam, dowels, mesh, plaster and labor do not depend on the thickness of the insulation. That is, there will not be much savings on materials and work between thicknesses of 30 mm and 100 mm. But the insulation will differ significantly. Therefore, it’s definitely not worth saving on the thickness of the insulation.

Moreover, in order for the dew point to move from the wall to the insulation, the thickness of the insulation should be about 100 mm.

The optimal, economically justified insulation thickness for aerated concrete walls is 100 mm.

If the walls of the house are made of high-density blocks from D600 and higher, or if the wall thickness is only 200, then 150 mm of insulation can be used.

Aerated concrete walls cannot be insulated immediately after their construction. The fact is that fresh factory aerated concrete is very wet, and this moisture must evaporate somewhere. Moisture comes out of the thickness of the wall both inside and outside the house, but what happens if you cover the outer part of the wall with insulation, for example polystyrene foam? All moisture will remain in the wall and will go inside the house, creating high humidity, mold and other inconveniences there.

It is worth noting that a damp wall retains heat in the house worse, and when negative temperatures the water in the wall turns into ice, slightly reducing the service life of aerated concrete.

Things are better with mineral (stone) wool, because it has good vapor-permeable properties and removes excess moisture. But then the aerated concrete itself is protected from the wind and takes much longer to dry. Plus, the mineral wool itself becomes more humid, worsening its thermal insulation properties.

In general, before insulating aerated concrete mineral wool, you need to wait 2-6 months, but for polystyrene foam it is better to wait 6-12 months.

The drying speed of aerated concrete is influenced by the following factors:

1. Wall thickness
2. Air temperature
3. Precipitation
4. Force of blown meters

For insulation aerated concrete house, mineral wool and polystyrene foam are usually used. For the impatient, we will answer right away - mineral wool is more expensive and better, polystyrene foam is cheaper and worse. Now let's try to figure out why this is so.

Mineral wool has excellent vapor permeability and removes excess moisture from the house and walls to the street. The vector of movement of water vapor is always directed from inside the house to the street.

This ensures a good microclimate in the house and the walls remain dry, and dry walls retain heat better. Moreover, mineral wool is absolutely non-flammable. Mineral wool slabs are more difficult to process and it is necessary to work with goggles, protective clothing, gloves and a respirator.

In terms of thermal insulation, wool and foam have almost the same properties.

Polystyrene foam is cheaper, easier to work with, it is easy to cut, and the cracks are filled with foam. Polystyrene foam is a flammable material and almost does not allow steam to pass through, which contributes to the accumulation of moisture in the walls and high humidity in the house. A house insulated with foam requires good ventilation, and intense ventilation blows heat out of the house.

Recuperators come to the rescue - special fans that heat the air entering the house using the heat of the exhaust air.

In general, mineral wool has important advantage- vapor permeability, and for an aerated concrete house it is best choice. But if finances are very pressing, you can also use polystyrene foam, but only with a thickness of 100 mm or more, so that the dew point is in the insulation + there is good ventilation in the house.

Schemes for insulating aerated concrete with stone wool

Foam insulation technology

Mineral wool insulation technology

Aerated concrete is one of the most popular today building materials for building a house. This type of concrete is characterized by a porous structure, due to which it acquires high thermal conductivity and low vapor permeability characteristics. That is why most buildings do not need to be insulated large quantities heat insulator. The thickness and number of layers of insulating material to create and maintain the necessary temperature regime in the home is selected depending on the climatic region and the type of walls.

What is aerated concrete?

Aerated concrete is an artificial stone product that belongs to lightweight concrete with medium pore size. It is light in weight compared to other building materials. It includes:

• Cement
• Sand
• Gas-forming agents, which are usually aluminum powders
• Ash, lime, slag and gypsum impurities

When these materials are combined with water, a chemical reaction occurs with the formation of hydrogen, which is the creator of cells in the stone. Blocks and slabs are formed from the resulting product required sizes and then dry them using high temperatures. Aerated block easily lends itself to any type of processing, has excellent fire resistance properties, is environmentally friendly, retains heat well and maintains sound insulation. But with all the advantages of aerated concrete, it still needs insulation.

Home owners in regions with harsh climatic conditions should pay special attention to this, because the thermal insulation properties of this material may not be enough to maintain the required level of heat. Also, if water gets inside the cells and freezes in winter period expansion will occur followed by a gradual rupture of the walls. Insulation is less susceptible to deformation from freezing moisture, and it is much easier to replace than to restore walls.

Choice of insulation: mineral wool or polystyrene foam?

The modern construction market offers a variety of materials for creating thermal insulation on the outside of aerated concrete houses. Let's look at the most popular of them - mineral wool and polystyrene foam - and identify the pros and cons of each of these materials.

These two insulation materials are similar in many respects. They have almost the same service life and mechanical characteristics. For rodents, foam is more preferable due to its airy structure. They easily gnaw through it and make their burrows in it. To prevent this from happening, it is necessary to carefully finish the façade with plaster. But rodents cannot stand mineral wool. It is much easier to work with polystyrene foam; it can be cut well; if cracks appear in it, they can be easily sealed with construction foam. The working process with mineral wool is a little more complicated. Also, when working with this insulation, you must use protective clothing.

There are significant differences between materials in terms of vapor permeability. The high vapor permeability properties of mineral wool do not deprive the walls of the ability to “breathe”. Polystyrene foam, on the contrary, is practically vapor-proof, which creates the effect of completely “packing” the house, in which the humidity of the walls increases by an average of 6%. With such a small percentage, there is still a deterioration in the performance properties of aerated concrete and the microclimatic parameters of housing.

From all of the above, it follows that mineral wool has a large number of advantages and is better suited for insulating the facade of the outside of a house made of aerated concrete, but it will also take more money to purchase this material. Purchasing polystyrene foam will cost much less. The choice is yours.

What should be the thermal insulation layer?

The thicker the insulation layer is laid, the more heat loss and heating costs will be reduced. But many, if they want to save on buying insulation, reduce its thickness. At the same time, the efficiency of the thermal insulation structure will decrease significantly, and the savings will be only 10%. The optimal insulation layer for aerated concrete walls in regions with a harsh continental climate should be 10 cm, and using thermal insulation with a layer thickness of less than 5 cm is simply not advisable.

Methods for insulating aerated concrete outside

There are several technologies that are used to carry out external insulation of the walls of a house made of aerated concrete. They must be performed strictly according to the instructions. It is also better not to replace materials with equivalent ones, but at a lower price. For example, special glue or plaster mortar for insulation they replace it with cheap and low-quality tile adhesive. It will cope with its task, but at the same time the vapor permeability and service life will be significantly reduced. Now let’s take a closer look at the options for insulating walls outside.

"Wet" easy option

“Wet” technology doesn’t really live up to its name. The condition of the façade remains extremely dry. The insulation is fixed to the walls of the house using glue and dowels with a wide head. After this, two leveling layers are applied plaster mixture, between which a reinforcing mesh made of plastic is placed. The condition of aerated concrete walls is initially smooth, so they do not require additional preparation. You just need to get rid of the dust covering them. Decorative or porous plasters are used as finishing. ceramic tiles for cladding.

"Wet" heavy version

This technology is used when cladding facades with stone or heavy ceramic-based slabs. In this case, the insulation is not glued, but is attached to the wall with massive hooks. A strong metal mesh is placed on top. The resulting structure is secured with metal plates. A thick layer of plaster based on sand and cement (20-40 mm) is applied to the mesh. At the final stage, the stone is laid. This option will require more costs than the “easy” one.

“Dry” option (Ventilated facade)

Also known as a ventilated or curtained façade. It is based on metal or wooden frame, which is created outside the facade. In the areas between its parts, insulation is installed, which is mineral wool, glass wool or polystyrene foam.

Advice: It is better not to give preference to polystyrene foam. This is due to its high fire hazard rates. Rising air currents from the ventilation facade can contribute to the fire of this insulation. Therefore, it is better to spend a little more money on purchasing mineral wool and thereby protect your home from fire.

Sheathing the frame is most often done with metal or plastic siding or wooden cladding boards. Porcelain stoneware slabs or slabs from natural stone rarely used in private construction to create curtain wall facades. The cost of these materials will be an order of magnitude higher than that of others, but thanks to for a long time operation of a ventilated façade made from these materials, payback will occur in approximately 5 or more years. The period, of course, is not short, but the facade will not require repairs for a long time.

Brick cladding

This option does not provide for the creation of an additional frame, so the insulation can be mounted directly on the surface of the walls. In this case, you should not forget about the air “pocket” for ventilation of the insulating material. This type of insulation is the most expensive, since large costs will be spent on purchasing bricks and increasing the surface of the foundation.

To summarize, you can see the following: in order to insulate a house made of aerated concrete with an optimal ratio of price, quality and aesthetic appeal, the best materials Mineral wool and polystyrene foam will be used for this purpose. Properly created thermal insulation will help not to lose precious heat and significantly save on heating.

Every day, with every mastered cycle, the house built according to the project with FORUMHOUSE is closer to becoming a dream come true for one of the families of our craftsmen. You can follow each stage of the work, and at the moment the insulation of the enclosing structures with mineral wool is already underway. This article will cover all aspects of the process, not only using the example of our home, but also the technology itself as a whole. Professionals reveal their secrets in a master class format for everyone:

• What determines the need for wall insulation?
• What determines the choice of insulation?
• Technology of insulation of enclosing structures with stone wool.

Why is insulation necessary?

Aerated concrete has a porous structure, due to which it is characterized by reduced thermal conductivity - for a dry structural block this coefficient varies between 0.096-0.14 W/(m °C), depending on the density. However, in masonry, even with a minimum thickness of the glued joint, the thermal conductivity of aerated concrete increases.

This occurs due to an increase in humidity, and due to armored belts and jumpers, and due to a variety of metal fasteners.

If, in accordance with SNiP, we use the method of temperature fields, then, taking into account the derived coefficient (0.7), the thermal resistance of the wall standard thickness will be less than what is specified in the standards.

We get: 3.65·0.7=2.55 m²·°C/W, against the required 3.13 m²·°C/W (for Moscow and the region). That is, in a house made of aerated concrete blocks 375 mm thick, the walls without additional insulation will actively release heat, which will entail an increase in heating costs. Therefore, in order to get an energy-efficient aerated concrete house, which in the context of constant growth of energy tariffs is one of the main tasks for private owners, it will be necessary to create a thermal circuit around the entire perimeter, and not just protective and decorative finishing. External insulation of facades is considered the most effective.

Polina Nosova Leading technical specialist at TechnoNIKOL

External insulation is preferable due to several factors:

• preserving the usable area of ​​the house;
• protection of walls from temperature fluctuations;
• increasing the service life of supporting structures by shifting the dew point (the area of ​​probable condensation) into the thermal circuit.

Why is it preferable for aerated concrete blocks?

The modern market of thermal insulation materials pleases with an abundance of offers for any design and budget; another thing is that not every insulation will be effective when applied to an aerated concrete base. The main principle of creating multi-layer enclosing structures is to increase the vapor permeability of each subsequent layer, starting from the inside. Despite the fact that disputes over the “breathing” of walls do not subside, steam is one of the products of our vital activity, and a certain part of it is discharged through the walls. To insulate aerated concrete, which is characterized by high vapor permeability, materials with even greater “ throughput", and mineral wool meets this criterion.

Two types are most in demand facade systems– “wet” facade with thin-layer finishing plaster and a hinged ventilated facade. In the first case, steam will be discharged from the walls into the insulation, and from it through a few millimeters of the reinforcing and plaster layer. In the second, the steam will be drawn out through a ventilation gap of several centimeters between the insulation and the facing screen.

High-strength slabs are used for plaster, and lightweight slabs with low compressibility are used for ventilated facades.

But if thin-layer plasters can be applied to other substrates, then in ventilated facade systems, fire safety standards allow the use of exclusively non-flammable heat insulators, and the NG group is only for mineral wool.

Polina Nosova

The fire safety of a home can be increased by using non-flammable thermal insulation - the melting point of stone fiber is more than 1000⁰C. In the event of a fire in a private house, such intensity is reached a couple of hours after the fire, this time is enough to save both household members and valuable property. It is important that even melting is not accompanied by the release of toxic gases and increased smoke formation.

Technology of insulation of enclosing structures with stone wool

The ventilated facade system with siding cladding is one of the most popular among private owners, as it allows you to level out all base errors, and is also available in plan independent execution. If over time, under the influence of heaving forces or for other reasons, cracks form in the masonry, the hinged facing screen will not be damaged. And given the fragility of aerated concrete and its requirement for the strictest adherence to technology, many self-builders prefer cladding as a more durable finishing layer. Insulation of aerated concrete walls with stone wool before finishing with siding or other facing material is carried out in several stages.

Preparation

When insulating during the reconstruction of an already in use building, all functional and decorative elements are removed from the walls, the surface is cleaned of dirt, and, if necessary, primed. If there is doubt about the load-bearing capacity, the base is checked by tapping with a hammer. Severe unevenness must be removed (protrusions) or repaired (depressions). When insulating during the construction process, the remaining mortar is removed from the walls. If there was heavy rainfall before work, you need to let the box dry.

Marking

Before installing the sheathing, markings are applied to the wall using a level or level, along which the frame elements will be attached. Distance between vertical beam lathing depends on the dimensions of the insulation.

Polina Nosova

In order for the slab to stand flat, without the formation of cracks and without deformation, and to fit tightly to the wall, the vertical axes are marked at a distance of 10-20 mm less than the width of the insulation (length, when laid horizontally). If the width is 600 mm, the clearance distance (between the inner edges of the beam) should be 580 or 590 mm.

Installation of vertical racks

Because complete absence Heat leakage through cold bridges is guaranteed only by two-layer insulation with overlapping joints; first, a vertical sheathing is assembled on the wall according to the markings. The thickness of the beam should correspond to the thickness of the slab, usually it is a 50x50 mm beam. The racks are fixed to aerated concrete with special fasteners, since ordinary dowel-nails or self-tapping screws used on other bases are not suitable for lightweight cellular concrete.

Laying slabs in a vertical frame

The thickness of the layers is selected based on thermotechnical calculation, for most regions a total thermal insulation thickness of 100-150 mm is sufficient. The absence of shrinkage and high elasticity of the slabs make it possible to simplify the technology and install mineral wool without additional fixation, laying it between the beams. If necessary, the slabs are trimmed with a knife or a hand saw with fine teeth. If, when assembling the sheathing, it was not possible to maintain the required distance, large gaps can be filled with a piece of slab.

Installation of horizontal racks

After laying the first layer, markings are applied under the horizontal frame, also using a level or level.

The distance between the posts also depends on the dimensions of the slab minus the compaction; the dimensions of the beam are selected to match the thickness of the slab.

The location of the second row of timber is made horizontal due to the fact that the further frame is under facing material will be attached to it in vertical arrangement with a step of 400 mm under the siding.

Laying slabs in a horizontal frame

Thermal insulation slabs are laid outward, with the seams offset, which allows you to completely get rid of cold bridges, even taking into account the use of metal fasteners during installation vertical racks.

Protective layer

To protect the insulation from atmospheric influences and the unhindered removal of condensate, a vapor-permeable, moisture- and wind-proof membrane is laid on top of the thermal circuit.

Despite the prevailing opinion that the feasibility of insulation is questionable, since the costs will significantly exceed possible energy savings even in the long term, heat calculations and practice prove the opposite. Aerated concrete house, insulated with stone wool, is not only comfortable, but also economical living.

Comments:

Insulation of aerated concrete walls is necessary in order to make the room warmer and reduce the cost of heating a residential building. Today, the choice of materials for insulating aerated concrete surfaces is quite large. Moreover, some insulation materials are distinguished by their low price, but no less high physical characteristics and heat-insulating parameters. It is not difficult to insulate the walls of a house made of aerated concrete; installation requires a minimum number of tools and materials.

Insulation of aerated concrete - which insulation to choose

To understand how to insulate a house, you need to know what thermal insulation materials exist. Previously, houses were insulated only with plaster, today there are a number of insulation materials that will help not only retain heat, but also not spend a lot of money on their purchase. In order to insulate aerated concrete walls from the outside, the following materials can be used:

• mineral wool;
• expanded polystyrene (penoplex);
• polyurethane foam.

Mineral wool is the most popular and effective thermal insulation material for insulating a house. Its basis is glassy fibers. This material is environmentally friendly and has excellent properties vapor permeable and does not burn. But to insulate aerated concrete walls with mineral wool, it must be used only with a vapor barrier material, since mineral wool absorbs moisture. Moreover, the walls need to be protected both outside and inside.

Penoplex is a dense and durable insulating material and has high thermal insulation, waterproof, and soundproofing properties. The thickness of the slabs is from 30 to 50 mm. Fastening polystyrene foam (foam) is simple and quick. But this insulation for aerated concrete walls does not have the same fire-resistant properties as mineral wool.

Polyurethane foam is characterized by high thermal insulation properties; installation of insulation is not difficult. The construction mixture must be applied under pressure to the wall. After polyurethane foam is applied to aerated concrete, it is bonded to the wall surface, foaming occurs and a protective warm layer is formed.

Some builders use foam glass and wood (cork) boards to insulate aerated concrete walls. But in such cases, it will be quite difficult to carry out the installation yourself; you may need the help of specialists.

You can insulate a house made of aerated concrete with polystyrene foam or standard plaster. This option is the cheapest, but it has one big disadvantage - aerated concrete blocks after applying plaster to them, they lose their vapor-permeable properties, and thermal insulation characteristics worse than when using other insulation materials.

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Insulating a house made of aerated concrete - tools and materials

To insulate an aerated concrete wall you will need:

• thermal insulation material;
• dowels;
• roofing felt;
• metal profiles;
• fiberglass mesh;
• any container for making glue;
• building level;
• hammer drill;
• perforated corners.

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Insulation of a house made of aerated concrete blocks from the outside with mineral wool

It should be noted that heat leakage depends on how correctly the insulation is applied. The seams and joints between the insulation need to be closed as much as possible, and for this it is better to use non-standard cement mortar, but a special glue for mineral wool. In this case, there will be no heat leakage. For external wall insulation and thermal insulation, the ideal thickness of mineral wool slabs is 50 mm.

First of all, you need to stir the adhesive, after which you still need to let it sit for about 10 minutes and only then start insulating it. The outer surface of the aerated concrete wall must be cleaned of dirt and dust for better adhesion of the insulation and aerated concrete. An adhesive composition is applied to the mineral wool sheets; the sheets must be placed against the wall, pressed and released. In the same way, you need to go over the entire area of ​​​​the aerated concrete wall. After the glue has dried, use a punch to make four holes around the perimeter of each sheet of mineral wool. Use special umbrella dowels to secure the sheets.

The next stage is stretching a special mesh around the entire perimeter of the mineral wool sheets. It is necessary to apply a layer of adhesive to it. After the additional layer of glue has dried, the already insulated wall must be puttied with a vapor-permeable compound and painted.

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Insulation of aerated concrete walls with polystyrene foam

Expanded polystyrene is ordinary foam plastic, that is, a material that is filled with gas. The basis of the insulation material is polystyrene and its compounds. Polyfoam is suitable for insulating external and external walls of any aerated concrete room. The thicker the sheets, the better the heat will be retained. The advantages of this insulation include its high resistance to different materials, weather conditions, and temperature changes. The thermal insulation material has excellent vapor permeability and resistance to fungi and mold. For reference, a 12 cm layer of polystyrene foam can replace brick wall 20 cm. Installing foam plastic on aerated concrete walls is not at all difficult; no construction skills or abilities are required.

The surface of aerated concrete walls must first be sanded and leveled. Secure with dowels metal profiles on the wall. They must be attached as firmly as possible. For the surface of the walls, it is better to use solid foam plastic; in places where it is impossible to install whole slabs, it is necessary to use pieces of insulation that correspond to the dimensions. The glue is diluted and applied to penoplex (expanded polystyrene). Temperature factors should be taken into account when insulating aerated concrete walls. The air temperature should not be below 7 ° C. Otherwise low temperature air may prevent the adhesive from drying properly.

In some cases, individual slabs may not be smooth enough, so before applying the adhesive composition, it is better to process the foam (foam or polystyrene foam) using a grinding machine or sandpaper. You need to glue the sheets starting from the bottom of the building - first the base, then the facade. After gluing is completed, the insulation sheets must be secured with dowels (6 pieces for each sheet). Joints and seams need to be coated with glue.

You definitely need to pay attention to the adhesive composition - it should suit your needs chemical composition for penoplex. Otherwise, the aggressive substances present may destroy the structure of the insulation. After the glue has dried, it is necessary to apply cladding to the insulating layer. You can do this using metal mesh, which will be attached to the insulation with glue or concrete mortar. It is necessary to make a penoplex lining in order to prevent the influence of external environment, which can destroy the thermal insulation material. Penoplex is afraid of temperature changes, direct sunlight, and precipitation.

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Insulation of walls with polyurethane foam

Polyurethane foam is mainly applied to aerated concrete walls by spraying. To make the solution, you will need a special container in which the polyisocyanate and polyol will be mixed. After foaming the composition carbon dioxide it heats up. The composition is sprayed onto insulated surfaces using a spray gun under pressure. It should be noted that polyurethane foam is quite easy to apply to the surface of aerated concrete walls.

Polyurethane foam is popular because it has high adhesive characteristics, creates an insulating layer without joints and seams, which increases the thermal insulation properties several times. In addition, the material is characterized by low thermal conductivity, light weight, durability, resistance to fire, mold and rodents.

You can carry out work on insulating aerated concrete from the inside of the house in the same way as from the outside. Aerated concrete can be insulated both during construction and during repair work. Internal insulation carried out in places that are more susceptible to cold.

Aerated concrete building blocks refer to products made from cellular concrete, since this artificial one has a solid structure with evenly distributed air pores filled with gas. The diameter of the gas pores is up to 3 mm, the solid structure consists of Portland cement, purified quartz sand and gas-forming additives. For special cases, the material may contain additives of gypsum or alabaster, slaked lime, ash or slag waste from the metallurgical industry. Aerated concrete is indispensable in construction, but traditionally insulating a house made of aerated concrete from the outside is necessary due to its insufficiently low moisture and vapor permeability. We will consider below what materials and methods are used to insulate aerated concrete walls from the outside.

Insulation technology and choice of material

The peculiarity of all types of cellular concrete is their ability to “breathe”, and this has both advantages and disadvantages. The disadvantage of the high vapor and moisture permeability of aerated concrete surfaces is that they do not prevent moisture and temperature fluctuations from air flows coming from outside, which manifests itself in changes in temperature in the building. Therefore, insulating the facade of a house made of aerated concrete also requires the installation of waterproofing in order to reduce the influence of atmospheric factors on the microclimate. It is considered good practice in construction to observe a decrease in the coefficient of vapor permeability of building materials as they approach the outer surface of the walls.

Practical observations show that if the outer layer of materials has a lower vapor permeability than the inner layers of the wall, then moisture will certainly condense in the wall over time, causing irreversible destructive processes in the building.

The air inside your home will always be more humid than the outside atmosphere, especially in winter. Partial pressure (the pressure of an individual element in an atmospheric gas mixture) in a house increases as the difference between the outside and inside temperatures and the volume of water vapor in the air increases. When water vapor tries to penetrate into the room, it is prevented by a less vapor-permeable layer, so the moisture begins to condense. In addition, when moisture condenses, another process occurs - the formation of a “dew point”, which, if the building layers are incorrectly positioned, will move inside the wall, which is unacceptable, since it also contributes to the onset of condensation.

The table shows data on how to insulate a house made of aerated concrete from the outside, and the vapor permeability of these insulation materials for exterior use, and decide how best to insulate your home based on actual data:

Construction materials	Vapor permeability coefficient, mg/(m h Pa)
Concrete walls	0,031
Plaster sand-cement mortar	0,095
Plaster lime-sand-cement mortar	0,096
Plaster sand-lime mortar	0,118
Sand-lime brick walls	0,12
Foam concrete and aerated concrete surfaces with a material density of 1000 kg/m 3	0,12
with material density ≥ 700 kg/m 3	0,15
with material density ≥ 500 kg/m 3	0,16
with material density ≥ 450 kg/m 3	0,25
Coniferous trees across the cut	0,07
Coniferous wood along the cut	0,31
Chipboard fiberboard with material density ≥ 500 kg/m 3	0,14
Chipboard fiberboard with material density ≥ 450 kg/m 3	0,2
Plasterboard partitions	0,073
Mineral stone wool with a material density ≥ 170 kg/m 3	0,31
— with a material density ≥ 130-170 kg/m 3	0,31
- with a material density ≥ 45-65 kg/m 3	0,34
- with a material density ≥ 30-50 kg/m 3	0,38
Mineral fiberglass wool with a material density ≥ 70-80 kg/m 3	0,5
- with a material density ≥ 40-60 kg/m 3	0,52
— with a material density ≥ 25-35 kg/m 3	0,53
— with a material density ≥ 20 kg/m 3	0,54
- with a material density of 17-15 kg/m 3	0,55
Extruded polystyrene foam	0,0052
Slab foam with material density ≥ 15-40 kg/m 3	0,051
Ecowool	0,31-0,67
Polyurethane foam	0,053
Polymer urea	0,00021
Ruberoid and glassine waterproofing material	0-0,0012
Polyethylene	0
Glazed ceramic tiles	0
Clinker tiles	0,018

The tabular data shows that even plaster finishing has a lower coefficient of vapor permeability, and among the insulation materials suitable for external insulation only mineral wool, ecowool and similar insulation materials that allow a larger volume of moisture and air to pass through.

The thermal resistance, strength and service life of aerated concrete ensure high-quality insulation of aerated concrete, and for this three conditions must be met:

1. To ensure high-quality thermal insulation of a house, its walls must be heated evenly all year round;
2. The dew point should be located outside the walls of the aerated concrete house, namely in the layer of insulated mass;
3. Reliable protection of building materials from atmospheric influences in various forms.

Regulatory documents provide for thermal insulation of aerated concrete with foam plastic or other materials if the walls are thick< 350 мм. Избежать утепления увеличением толщины стены не получится:

1. It is advisable to cover a house made of aerated concrete with insulation only from the outside, so that the dew point is as close as possible to the outer surface of the walls;
2. The vapor permeability of external insulation must be ≥ 0.17 mg/(m h Pa);
3. For exterior finishing It is recommended to use wind protection and water barriers.

A ventilated facade with insulation meets these requirements. On walls with sufficient thickness of gas blocks for optimal resistance to heat transfer, a ventilated facade is installed without a layer of thermal insulation. In this case, it is necessary to install forced ventilation in the house, since the dew point will be located in the wall.

External insulation

Thermal insulation of the house from the outside is mounted on the frame (sheathing). Mounted on top façade slabs or sheets, and an air gap is left between these two salts for ventilation. Thus, the facade protects the insulating material and the gas block from cold and moisture, and ventilation prevents the wall from becoming waterlogged. To better insulate the house, a vapor-permeable membrane film is applied to the thermal insulation layer. The process of layer-by-layer work with insulation looks like this:

1. Metal or wooden frame;
2. Insulation made of polystyrene foam or mineral wool on the first frame:
3. Wind protection and vapor barrier;
4. Second metal or wooden frame;
5. Exterior materials for finishing the facade of a house.

Before insulating a house made of aerated concrete, dry timber is prepared. The walls of the house must also be dry and clean, therefore, to cover a house with aerated concrete, prolonged sunny weather is desirable. Also, the walls must be primed with deep penetration compounds before insulation. Considering that aerated concrete is a porous material, the primer is applied in two layers, preferably with a spray bottle.

The first frame will hold the insulation, so its depth should match the thickness of the insulation. A shelf is attached to the bottom of the wall, which will set the horizontal position of the insulation layer, hold the insulation and create the size of the ventilation space.

The beam of the first frame is mounted vertically - on both sides on the corner corners with a fastening step of 40-50 cm. Use 3.9 x 35 mm self-tapping screws, two in each corner shelf, maintaining a distance between the beams of 50-60 cm.

The specific pitch of the timber is determined by the width of the insulation: since the house is sheathed different materials, then the pitch of the timber in the frame will be different. For example, when working with mineral wool 600 mm wide, the distance between the centers of the beam should be 55 cm, and with a roll width of 122 cm, the step between the beams is 120 cm. But with a large frame length, this distance will be too large, so the insulation roll is either cut in half, or it is additionally secured with umbrella dowels. Mineral wool is good because it has a variable size, and it is easier to install than solid insulation.

The mineral wool is protected from above with a vapor barrier membrane film - the insulation itself can quickly become saturated with moisture. The film can be securely and quickly secured with a construction stapler, from bottom to top, overlapping, with an overlap of 5-10 cm.

A second wooden frame is attached to these layers to form a ventilation gap and remove moisture from building materials. The thickness of the ventilation space is up to 40 mm, so you can use timber with a section of 30 x 40 mm, 40 x 40 mm, 50 x 50 mm.

https://youtu.be/nzB_vXety-U

The beam of the second frame is selected with a length of 30% of the wall height. The remaining length is obtained using scraps of the required length, and this is done in order to provide as much space inside as possible - the distance between the beams is left 7-10 cm, taking into account the fastening of the sheet facade finishing material. For example, if this is siding, then the distance is made up to 10 cm, depending on the width of the strip. The beam is attached to 3.9 x 75 mm screws.

In addition to siding, sandwich panels, metal profiles, lining, plastic panels. For each material, the distance between the frame beams changes.

Mineral slabs - insulation technology

Soft mineral wool has disadvantages - high vapor permeability and low thermal conductivity, so professionals recommend mineral slabs for insulation - they are much stronger and therefore less susceptible to deformation. They are fastened end-to-end using umbrella dowels (see last picture).

When working with mineral slabs, you don’t have to build the first frame, but install the insulation directly on steel “U”-shaped hardware, builders call them “butterflies.”

“U”-shaped plates are attached to aerated concrete with self-tapping screws: vertically in increments of 600 mm, horizontally in increments of 500 mm. In places where dowels and wide caps are driven in, recesses are cut out for them in the insulation. The plate is placed on plates and additionally secured to the wall with umbrella dowels. The recesses that were cut out for the dowel heads need to be filled polyurethane foam. The slabs, like mineral wool, are covered with a vapor barrier from the bottom up. The timber frame will serve as a ventilation gap, as in the example with mineral wool.

The last stage is attaching siding or other cladding. Laying slabs end-to-end is a clear advantage of this technology over the previous one, since an almost monolithic and homogeneous insulating layer of material is formed. Another advantage is that there is less deformation of the timber; in addition, for the frame you can use metal UD and SD profiles, which do not deform at all.