Any owner who decides to build Vacation home, wants it to be warm, cozy, and living in it comfortable. An ideal building material for the construction of a private home in Lately cellular concrete, in particular foam blocks, is deservedly recognized.

In the article we will talk about what thickness of foam block walls should be for load-bearing walls and partitions in order for the building to be strong, reliable and durable.

Comparative characteristics of masonry materials

So, for clarity, let’s create a table of the main indicators cellular concrete in comparison with other analogues.

Let's take the most popular materials for construction residential buildings: brick, expanded clay and aerated concrete:

Indicators	Brick (clay and silicate)	Expanded clay concrete	Aerated concrete	Foam concrete
Weight 1 m3 (kg)	1200–2000	500–900	90–900	90–900
Density (kg/m3)	1550–1950	900–1200	300–1200	300–1200
Thermal conductivity (W/m*K)	0,6–1,15	0,75–0,98	0,07–0,38	0,07–0,38
Water absorption (% by weight)	12–16	18	20	14
Frost resistance (number of cycles)	25	25	35	35
Compressive Strength(Mpa)	2,5–30	3,5–7,5	0,15–25,0	0,1–12,5

Based on the table, we will draw conclusions on the advantages of foam concrete:

• By weight foam blocks are equal only to aerated concrete (see), their low weight makes it easier to transport and carry. And if we take into account the significant size of the blocks, then laying and reducing construction time.

• By thermal conductivity foam and gas blocks have no equal, which means that a house made from these materials is more ergonomic, it will always be warm and cozy with low heating costs.

• Water absorption foam concrete has significantly less than other analogues, which means that the risk of moisture penetration into the room is reduced, and, accordingly, dampening of the walls, the formation of fungus, mold, etc.

Important! The humidity in the room should be no more than 60%, but in any case, waterproofing wall surfaces is done with your own hands with all responsibility, since the moisture absorption of the foam block, although small, is still present.

• Number of freezing and defrosting cycles foam blocks have more than, for example, brick, so the service life of the building increases. By the way, experts say that over the years the foam block only gains strength, but the brick, on the contrary, is susceptible to destruction.

• Foam concrete performs slightly worse in compression than brick or aerated concrete, but this indicator depends on the brand of foam blocks - the higher it is, the stronger the wall. You can increase this parameter.

Particular mention must be made of the cost of this material; the price of foam blocks is 2–3 times lower than that of other building materials.

Types and brands of foam blocks

We digressed a little from the topic, we promised to talk about how thick a wall made of foam blocks should be. And it depends precisely on the type of foam concrete and brand, so we provide a table of existing designations for blocks made of cellular concrete.

It must be said that all foam blocks are also divided by type, they are:

• Thermal insulation.

They are used for insulation of the contour of building walls and installation of internal self-containing load-bearing partitions.

• Structural and thermal insulation.

They are used both for additional insulation, and for the construction of partitions and walls of low-rise buildings.

• Structural.

They serve for the construction of critical, load-bearing structures (foundations (see), plinths, walls).

Important! The brand of foam block is designated by the letter D, for example, the D 800 block has a density of 800 kg/m3. As density increases, they deteriorate thermal insulation qualities blocks, therefore it is recommended to additionally insulate structural types.

About unique features foam concrete has been said quite a lot, we will not analyze its pros and cons in detail, we will finally move on to choosing the thickness of the walls.

Features of determining wall thickness

To clearly show the advantage thermal insulation properties foam concrete, let’s take a wall of 60 cm foam blocks, and now let’s see what the thickness of a wall made of other materials that has the same thermal conductivity should be equal to:

• Beam – 52 cm.
• Expanded clay concrete – 101 cm.
• Brick – 230 cm.
• Concrete – 450 cm.

Foam concrete is equal only to wood in terms of heat retention; all other materials will require additional insulation, otherwise there will be a huge cost overrun and incredible thickness of the walls.

The following parameters influence the choice of thickness:

If the building is one-story, the ceiling is wooden, the roof is not heavy, then grades D600–D800 are usually used for load-bearing walls. With a house of several floors and reinforced concrete floors higher grades D900–D1200 are used. For partitions, blocks D200–D400 are used.

1. Dimensions and thickness of foam blocks.

In areas with a temperate climate, houses are built with a wall thickness of 30 cm; for this, they take a foam block measuring 30x30x60 (width, height, length) and lay it lengthwise.

For cold regions, walls are erected with a thickness of 60 cm, the same block is laid in two rows.

A foam block wall thickness of 20 cm is made mainly for internal load-bearing partitions, both interior and separating the living space from the veranda, as well as for garages and outbuildings. Self-supporting partitions in bathrooms or storage rooms are mounted from semi-blocks 10(15)x20(30)x60.

1. Soundproofing of premises.

If you need to isolate a room from noise from next room or from the street, it is better to take wider blocks. For example, foam blocks with a thickness of 30 cm will reduce the noise level more reliably than with a width of 20 or 15 cm. A thickness of 10–15 cm will require additional sound insulation.

1. Insulation.

When external insulation of surfaces is planned, the thickness of the foam blocks is taken to be a maximum of 30 cm; brick, thin half-blocks (10x20(30)x60) or other facing materials are used for finishing. Due to the insulation layer placed between the main wall and the sheathing, the thermal insulation of the room increases significantly.

If the house is built without additional insulation (for example, foam blocks with ready-made facade), then the instructions recommend increasing the wall thickness to 60 cm.

Nowadays, insulated foam blocks are produced, which immediately contain insulation and facing material in their structure. In this case, the wall is made of foam blocks (thickness 20 cm + 8–10 cm of polystyrene foam + facade tiles) will withstand even severe frosts perfectly.

Important! We must remember that the higher the density, the worse the sound and heat insulation. For example, the thermal conductivity of a wall made of D600 foam blocks with a thickness of 45 cm is equal to a wall made of D800, but with a thickness of 68 cm!

The same goes for internal layout. For partitions, a D200 foam block thickness of 10–15 cm will better soundproof a room than D300 or D400 of the same thickness.

Accurately calculate all parameters for wall thickness, quantity required material, brand of foam blocks can be found on the calculator available on any construction site. If you want to calculate the wall thickness yourself, then refer to SNIP II-3-79. It contains the values ​​of all the necessary indicators for calculating the heat transfer of any wall composition and different densities of foam blocks.

Conclusion

As we found out, the thickness of the foam block for partitions and walls of a building is calculated quite simply. In addition to the presented parameters, it also depends on the area of ​​the premises, the desires and financial capabilities of the owners.

You will still have to make some adjustments to the size of the plot or the type of foundation. But it is still advisable to adhere to the basic rules. Additional information is contained in the video presented in this article; we hope that the photos will also help you quickly decide on this issue.

In this article I will present my arguments in favor of insulating walls made of foam blocks. It’s not that I’m a supporter of this particular construction technology, but it’s precisely about the insulation of foam blocks that a lot of controversy arises due to the fact that they have a fairly low thermal conductivity coefficient.

Many believe that the thickness of 375 mm of foam and aerated concrete blocks is quite enough for building a house in the western part of Russia. Having made calculations, I can say that this is not so, and it is necessary to insulate houses made of foam and aerated concrete blocks.

Minimum permissible thickness of a wall made of foam blocks according to bearing capacity— 300 mm with a strength class of at least B2.0 for two-story buildings, we will build on it.

Reason for the need for external insulation No. 1

If you finish the surface with plaster, then moisture will still partially penetrate the foam block and thereby worsen its thermal properties, so for comparison we will accept the brick finish because in the long term it is still more profitable than plaster.

• Foam block D600 - 300 mm x 2800 rub/m³=840 rub/m²;
• Adhesive for masonry, consumption 19.5 kg per 1 m³ of masonry, price 288 rubles/25 kg=11.52 rubles/kg, total 19.5*0.3*11.52=67.4 rubles/m²;
• The cost of installation of foam blocks is 2350 rubles/m³, a total of 705 rubles/m².

Total excluding finishing and cladding - 1612.4 rubles/m².

Facing brick finishing:

• Facing brick price 10 rub/m², consumption 51 pcs/m²=510 rub/m²;
• Masonry mortar 2350 rub/m³, consumption 0.0288 m³/m²=67.68 rub/m²;
• Flexible connections 22 rubles/piece, consumption 4 pieces/m²=88 rubles/m²;
• The cost of work is 1100 rubles/m².

The total cost of finishing with facing brick is 1,765.68 rubles/m².

The total cost of the wall when finishing with brick is RUB 3,378.08/m².

Now let's compare it to a 375 mm wall.

The thermal resistance of a wall made of foam block with a thickness of 375 mm is 2.83 (m 2 ∙ °C).

Let's calculate the cost of 1 m² of such a wall:

• Foam block D600 - 375 mm x 2800 rub/m³=1050 rub/m²;
• Adhesive for masonry, consumption 19.5 kg per 1 m³ of masonry, price 288 rubles/25 kg=11.52 rubles/kg, total 19.5*0.375*11.52=84.24 rubles/m²;
• The cost of installation of foam blocks is 2350 rubles/m³, a total of 881.25 rubles/m².

Total excluding finishing and cladding—RUB 2,015.49/m².

The cost of finishing is the same, we find that a wall with a thickness of 375 mm is more expensive than a wall of 300 mm by 403.09 rubles/m².

Now let’s calculate the amount of heat that will escape through these walls during the heating period for the Moscow region. We calculate heat loss using the formula:

The internal temperature (tint) is +22 °C;

the average outdoor air temperature during the heating period (tout) for Moscow is -2.2 °C (see table 3.1 SP 131.13330.2012);

F - surface area, calculated per 1 m²;

τ - the heating period time of 205 days is multiplied by 24 hours, a total of 4920 hours;

R is the thermal resistance of the wall.

Total heat loss for a 300 mm wall Q=(22+2.2)*1*4920/2.3=51767 Wh;

for a wall 375 mm Q=(22+2.2)*1*4920/2.83=42072 Wh.

Convert kWh to MJ (1 kW*h=3.6 MJ):

wall 300 mm - 186.36 MJ;

wall 375 mm - 151.46 MJ.

Savings on heating are 34.9 MJ.

Construction country house always entails a lot of waste, effort and calculations, which, however, cannot be carried out by everyone who wants to. After all, it’s not enough to want to build a house from foam concrete materials; you need to know the features and subtleties of the work process. In this article we will look at what thickness of foam block walls is required for a residential building, and we will also build it ourselves, according to all the rules and standards.

Material characteristics

Before deciding how thick a wall made of foam blocks should be, let's take a look at the advantages of this material:

• High compressive strength - permissible values ​​from 3.5 to 5 MPa. All this suggests that two or even three-story houses can be built from foam blocks.
• With such a light weight, the foam concrete block has a low density (depending on the quality of the material - from 400 to 1600 kg/m), 2-3 times lower than that of expanded clay.
• Foam block can be compared with wood in its thermal conductivity, and in comparison with ceramic bricks, he even has an advantage. A wall made of clay blocks 60 cm thick retains heat in the same way as 200 mm foam concrete masonry.
• It is worth noting soundproofing properties you do not need this material additional protection from noise if the blocks are laid well.
• And, of course, the price of foam blocks cannot be compared with anything. This product, even taking into account transport services, will cost you less than all other building materials.

Finally, you can point out the availability of masonry materials, that is, you can build a house from foam concrete blocks with your own hands, without special preparation.

Note! Do not forget that the too low cost of foam blocks is not a sign of quality; most likely, these are second-rate products that were made from waste of high-quality raw materials. So try to save wisely.

Related articles:

Wall thickness is a trick question

In your search for what thickness to choose for a wall made of foam blocks, you may come across many different arguments and judgments, most of which will turn out to be unreliable information.

To protect yourself and find the right solution, we will describe several features that you should consider:

• Firstly, it is important to understand how low it goes in winter time temperature. In areas where winters are very harsh, thicker walls with additional thermal insulation are certainly required.
• Secondly, decide on the insulation - will you install it or make do ordinary plaster. For example, for houses where the thickness of the foam block wall is 300 mm, it is better to add thermal insulation material 50-100 mm thick.
• Third, insulation not only acts as a material that retains heat, but it also prevents the effects ultraviolet rays on the foam block.

For your information! The choice of foam concrete products should also be influenced by their density, which varies; the higher the density, the more expensive the material.

Determining the thickness

Now let's conclude from the above, the recommended thickness of external walls made of foam blocks for areas with moderate winters is 300 mm with a density of D600 and a layer of thermal insulation.

• This is, so to speak, golden mean, which is suitable for almost all regions of Russia. Additional thermal insulation on the outside of the house allows you to survive the winter without feeling the cold in the living space.
• As for strength, even if the house is planned to be two-story, then maximum load on the walls of the first floor will not exceed 20 tons (together with the roof, floor slabs and furnishings). And from technical characteristics we know that every 100 mm of foam block can withstand a load of up to 10 tons.

Important! The only thing worth paying attention to is strength and resistance to physical influences. 300 mm is small enough, such a wall can be easily broken through with a sledgehammer, but 400 mm blocks are already denser and stronger.

On the other hand, you can clearly use an example to find out what thickness a wall made of foam blocks should be.

Thermal conductivity calculations

You should know that resistance external wall heat transfer (with all finishing materials) must exceed 3.5 degrees per m2/W.

To determine the thickness, let's take a closer look at this process based on the different densities of foam concrete:

• From the technical characteristics you can find out that the D600 and D800 blocks have coefficients of 0.14 and 0.21 deg * m2 / W, respectively.
• As finishing materials facing brick is used (0.56 deg*m2/W) and decorative plaster(0.58 deg*m2/W).

Let's start the calculation:

• First, let's decide on the thickness of the brickwork and plaster, usually (for facades without thermal insulation materials) the brick is laid in two rows, that is, 120 mm.
• Now let's convert this into meters and divide by the thermal conductivity coefficient facing material, the result is a resistance equal to 0.21.
• We do the same with plaster and as a result the resistance is 0.03.

Now all that remains is to substitute all our numbers into a simple formula:

• Foam concrete with a density of 600 = 3.5 (total heat transfer resistance) – 0.21 (brick) – 0.03 (plaster) and all this is multiplied by 0.14 (foam block coefficient). As a result, we get about 450 mm (don’t forget to convert from meters). This is exactly the thickness that a wall with the materials described above should be.
• Foam concrete with a density of 800 - (3.5 - 0.21 - 0.03) * 0.21 = about 680 mm.

As you can see, in the second case you will need a thicker wall, which means there will be more costs. On the other hand, add polystyrene foam (the most common insulation) and the thickness of the facade will be significantly reduced.

Important! Optimal thickness The walls of a cinder block house are calculated in a similar way, with one but - it is necessary to take into account the moisture-proof material, since without it this material will lose strength. On average, the walls of buildings made of cinder blocks, in areas with possible cold snaps down to -30 degrees, are erected with a thickness of 70-80 cm.

Construction process - building walls

And now, as promised, instructions for the construction of external walls, taking into account all the factors affecting the material:

• First, you need to prepare the foundation for work: clean it from dust and dirt, level it if there are unevennesses.
• After, count required amount materials: foam blocks and adhesive solution. To make it easier for you to navigate, one cubic meter about 30 blocks measuring 200x300x600 mm (we chose them so that the wall thickness was 300 mm). The glue calculation can be taken as an approximate amount - about 30 kg per 1 m3 of wall, so the main thing is to find out the total area of ​​​​the walls being built.

Note! It is better to decide on the amount of materials at the design stage in order to avoid extra costs, take into account all points, up to window openings and internal partitions.

• When all the materials and tools are in place, you can begin to prepare the solution, unless, of course, you bought a ready-made mixture.
• Initially, the glue is applied to the surface of the foam block, which is placed on the foundation or floor slab.
• Before the adjacent block is laid, the end is thoroughly coated with glue so that there are no empty gaps between the products.

• To remove excess glue from under the foam concrete, tap it with a mallet.
• The second row is laid out with the materials shifted so that the vertical joints do not coincide; to do this, you need to cut one block in half and start laying from half.

Since foam concrete products are easy to process, you should not have any problems with making holes for window and door openings.

Now all that remains is to finish and insulate the façade of the foam block house:

• For finishing with bricks, you should foam concrete wall, between the blocks, fasten several rods of thin reinforcement, this is necessary in order to connect the inner wall with brickwork. However, first you need to install polystyrene foam boards using disc nails.
• If you use only plaster, then initially, on top finished wall, the reinforcing mesh should be fixed. Then you need to apply a thick layer thermal insulation plaster so that it hides the mesh underneath. Finishing layer – decorative finishing, protecting the inner layer from ultraviolet radiation and moisture.

Features of working with foam concrete

In addition to all of the above, you should understand a few important points directly related to foam blocks:

• Calculation of wall thickness should be carried out according to the rules if you are confident in the quality building material. Do not forget that density is the main criterion by which a product is selected.
• For foam blocks it is better to use special adhesive solutions than a conventional cement-sand mixture. If you are not sure that you can maintain the correct proportions, it is better to purchase ready-made products that can be used immediately after opening the package.
• I would also like to clarify that foam concrete does not have increased resistance to water, so it is necessary to use additional hydrophobic materials. A small investment in protecting your walls will extend their service life by several years.

• For interior partitions it is enough to use foam blocks 200 mm thick, and some house builders even build interior walls 100 mm thick. In fact, this is enough, but do not forget that than thinner material, the lower the sound insulation. Therefore, soundproofing films are usually installed with such partitions.

Conclusion

As you can see, there are not so many factors influencing what the thickness of a cinder block wall will be and the determination of this parameter. These are mainly weather conditions and, of course, the presence of a second floor or attic space.

In any case, you need to adapt exactly to what you have, while focusing on your financial opportunities. Trying to guess the thickness of the load-bearing walls, decide on it in advance if you are using a strip foundation as a base.

In the video presented in this article you will find Additional information on this topic.

Hello, Nikolay.

First of all, I want to draw your attention to what foam blocks are and for what reason they should not be used for building a house. And if we’re going to consider cellular concrete, then use gas silicate blocks instead of foam blocks. aerated concrete blocks.

Let me explain.

Foam blocks is a type of cellular concrete, the production process of which is quite simple. Cement, sand and foaming agent are used. Organic or synthetic based compositions can be used as a foaming agent. In most cases, a synthetic-based foaming agent is used, due to the fact that its price is much lower than that of an organic foaming agent. But the disadvantages of synthetics include the presence in its composition of toxic components classified as the second class of danger. After mixing the components, the process of strengthening occurs “in the sun”. In the case of foam blocks, most often we are dealing with handicraft production. When purchasing foam blocks, you are unlikely to be provided with test reports for strength, thermal conductivity, and frost resistance. You won’t see a Sanitary and Epidemiological Supervision certificate either.

Gas silicate or aerated concrete blocks- also a type of cellular concrete, which is produced in serious industries. Foaming agents are not used. The process of strengthening occurs in autoclaves, where under a certain regime: pressure, humidity, temperature, it is possible to obtain a higher strength of the block with a density equal to that of the foam block. With a density of 500 kg/m 3, gas silicate blocks have the strength 35kgf/cm 2 (M35), with the same density, foam blocks will have a strength no higher 15kgf/cm 2 (M15).

It is unacceptable to erect load-bearing walls from a block with strength M15.

If you choose cellular concrete blocks, I recommend using gas silicate blocks.

If you still dare to build a house worth several million rubles, using load-bearing walls as material handmade foam blocks (2,100 rub/m3), characteristics (strength, thermal conductivity, frost resistance) which will not be supported by any documents, then the final costs will be lower by only 42,515 rubles in comparison with the costs of building a house using the most thermally efficient ones produced in Russia, ceramic blocksKerakam Kaiman 30.

A detailed comparative cost calculation that results in this difference is provided at the end of this answer.

When choosing between different materials for external walls, basic characteristics such as strength and thermal conductivity are usually compared. Compare the total costs.

In order.

1. Durability.

We design houses using gas silicate blocks with a density of 500 kg/m3 (D500). Compressive strength gas silicate blocks at this density - B2.5, which is equivalent to the strength grade M35(35 kgf/cm2).

We also use ceramic blocks for external walls. Kerakam Kaiman 30, the strength grade of which M75(75kgf/cm2).

What follows - the strength of ceramic blocksKerakam Kaiman 30exceed gas silicate blocks by more than 2 times.

Due to the fact that gas silicate blocks have low strength, according to the manufacturer’s instructions, row reinforcement of the masonry is required (every third row), with the installation of grooves, laying reinforcement rods in them and recessing the latter into a layer of glue.

Ceramic block masonry Kerakam Kaiman 30 reinforced only at the corners of the building, a meter in each direction. For reinforcement, a basalt-plastic mesh is used, laid in masonry joint. Labor-intensive gating and subsequent covering of the reinforcement in the groove with glue is not required.

When installing ceramic blocks, masonry mortar is applied only along the horizontal joint of the masonry. The mason applies the mortar to one and a half to two meters of masonry at once and places each subsequent block along the tongue and groove. The laying is carried out very quickly.

When installing gas silicate blocks, the solution must also be applied to lateral surface blocks. Obviously, the speed and complexity of masonry with this installation method will only increase.

For professional masons, sawing ceramic blocks is not difficult. For this purpose it is used reciprocating saw, using the same saw, gas silicate blocks are also sawed. Only one block needs to be cut in each row of the wall.

A builder you know recommends using three-layer masonry technology.
When choosing this technology you should understand.
The weak link in the three-layer construction of the external wall is the insulation.

The service life of mineral wool or expanded polystyrene is 20-25 years. This is due to the fact that the glue that connects the fibers in the mineral wool gradually evaporates.
Some developers believe that polystyrene foam will last longer. This is wrong. Over time, the thermal bonding of polystyrene foam balls to each other is disrupted due to the fact that heating season wet vapors entering the polystyrene foam from a heated room will condense in the polystyrene foam itself and freeze when negative temperatures. And as you know, ice has a larger volume than water, this leads to the fact that the ice “uncompresses” the thermally bonded balls, cycle after cycle destroying the thermal bonding of the latter.

The use of expanded polystyrene in combination with cellular concrete blocks is not advisable, because violated basic principle devices of multilayer structures - the vapor permeability of the layers should increase from the inside out. Violation of this principle will lead to an increase in the mass ratio of moisture in a structure made of cellular concrete blocks, which in turn will reduce the comfort of living in the house and worsen the thermal characteristics of the entire structure as a whole. Will shorten the lifespan of the building as a whole.

Processes that will develop during the destruction of insulation in a three-layer structure of an external wall.

• Losing their adhesive bond with each other, mineral wool fibers or polystyrene foam balls will begin to settle inside the wall structure, clogging the ventilation gap and exposing sections of the external wall of the house.
• A ventilation gap clogged with insulation fibers will cease to perform its function - removing wet vapors/promoting drying of the insulation layer.
• As a result, this will lead to a significant deterioration in the thermal characteristics of the remaining insulation, which in turn will affect thermal characteristics external wall and heating costs.
• The humidity of the external wall structure will increase from year to year, and this will affect not only the insulation but also the material load-bearing wall, and facing bricks.
• And if in such a situation you do not make major renovation façade of the house - break down the facing masonry, clean the façade of insulation residues, install new insulation, lay out new masonry face brick, the process of accelerated destruction of the facing masonry will begin and load-bearing structures Houses.

The second significant disadvantage of three-layer masonry is the complexity of the design; not all builders have the skills and knowledge of how to properly build three-layer masonry. This is one of the most complex structures external walls.

2. Thermal conductivity.

To begin with, we will determine the required thermal resistance for the external walls of residential buildings for the city of Moscow, as well as the thermal resistance created by the structures under consideration.

The ability of a structure to retain heat is determined by such a physical parameter as the thermal resistance of the structure ( R, m 2 *S/W).

Let us determine the degree-day of the heating period, °C ∙ day/year, using the formula (SNiP " Thermal protection buildings") for the city of Moscow.

GSOP = (t in - t from)z from,

Where,
t V- design temperature internal air buildings, °C, taken when calculating the enclosing structures of groups of buildings indicated in Table 3 (SNiP “Thermal protection of buildings”): according to pos. 1 - according to minimum values optimal temperature corresponding buildings according to GOST 30494 (in the range 20 - 22 °C);
t from- average outside air temperature, °C cold period, for the city Moscow meaning -2,2 °C;
z from- duration, days/year, of the heating period, adopted according to the set of rules for a period with an average daily outside air temperature of no more than 8 °C, for the city Moscow meaning 205 days.

GSOP = (20- (-2.2))*205 = 4,551.0 °C*day.

The value of the required thermal resistance for the external walls of residential buildings will be determined by the formula (SNiP "Thermal protection of buildings)

R tr 0 =a*GSOP+b

Where,
R tr 0- required thermal resistance;
a and b- coefficients, the values ​​of which should be taken according to Table No. 3 of SNiP “Thermal Protection of Buildings” for the corresponding groups of buildings, for residential buildings the value A should be taken equal to 0.00035, the value b - 1,4

R tr 0 =0.00035*4 551.0+1.4 = 2.9929 m 2 *S/W

Formula for calculating the conditional thermal resistance of the structure under consideration:

R0 = Σ δ n /λ n + 0,158

Where,
Σ – symbol of layer summation for multilayer structures;
δ - layer thickness in meters;
λ - thermal conductivity coefficient of the layer material subject to operational humidity;
n- layer number (for multilayer structures);
0,158 - correction factor, which can be taken as a constant for simplicity.

Formula for calculating the reduced thermal resistance.

R r 0 = R 0 x r

Where,
r– coefficient of thermal technical homogeneity of structures with heterogeneous sections (joints, heat-conducting inclusions, vestibules, etc.)

According to standard STO 00044807-001-2006 according to Table No. 8, the value of the coefficient of thermal uniformity r for masonry made of large-format hollow porous ceramic stones and gas silicate blocks should be taken equal to 0,98 .

At the same time, I would like to draw your attention to the fact that this coefficient does not take into account the fact that

1. we recommend masonry using warm masonry mortar (this significantly levels out the heterogeneity at the joints);
2. As load-bearing wall and facing masonry connections, we use not metal, but basalt-plastic connections, which conduct heat literally 100 times less than steel connections(this significantly levels out the inhomogeneities formed due to heat-conducting inclusions);
3. window slopes and doorways, according to our project documentation additionally insulated with extruded polystyrene foam (which eliminates heterogeneity in the areas of window and door openings, vestibules).

From which we can conclude that when following the instructions of our working documentation, the coefficient of masonry uniformity tends to unity. But in calculating the reduced thermal resistance R r 0 we will still use the table value of 0.98.

R r 0 must be greater than or equal to R 0 required.

We determine the operating mode of the building in order to understand what the thermal conductivity coefficient is λ a or λ in taken when calculating the conditional thermal resistance.

The method for determining the operating mode is described in detail in SNiP "Thermal protection of buildings" . Based on the specified normative document, let's follow the step-by-step instructions. 1st step. Let's define shumidity level of the building region - Moscow using Appendix B of SNiP "Thermal protection of buildings".

According to the table the city Moscow located in zone 2 (normal climate). We accept value 2 - normal climate. 2nd step. Using Table No. 1 of SNiP “Thermal protection of buildings” we determine the humidity conditions in the room. At the same time, I draw your attention to heating season air humidity in the room drops to 15-20%. During the heating season, air humidity must be raised to at least 35-40%. A humidity level of 40-50% is considered comfortable for humans. In order to raise the humidity level, it is necessary to ventilate the room, you can use air humidifiers, and installing an aquarium will help.

According to Table 1, the humidity conditions in the room during the heating period at air temperatures from 12 to 24 degrees and relative humidity up to 50% - dry. 3rd step. Using Table No. 2 of SNiP “Thermal protection of buildings” we determine the operating conditions. To do this, we find the intersection of the line with the value of the humidity regime in the room, in our case it is dry, with humidity column for the city Moscow, as was found out earlier, this value normal.

Summary. According to the SNiP methodology "Thermal protection of buildings" in the calculation of conditional thermal resistance ( R0) value should be applied under operating conditions A, i.e. thermal conductivity coefficient must be used λ a. You can see it here Thermal conductivity test report for ceramic blocks Kerakam Kaiman 30 . Thermal conductivity value λ a You can find it at the end of the document.

Let's consider laying an external wall using ceramic blocks Kerakam Kaiman 30 and handicraft foam blocks, lined with ceramic hollow bricks. For use case ceramic block Kerakam Kaiman 30 total wall thickness excluding plaster layer 430mm (300mm ceramic block Kerakam Kaiman 30+ 10mm technological gap filled with cement-perlite mortar + 120mm facing masonry). 1 layer(item 1) – 20mm heat-insulating cement-perlite plaster (thermal conductivity coefficient 0.18 W/m*C). 2 layer(item 2) – 300mm wall masonry using a block Kerakam Kaiman 30(thermal conductivity coefficient of masonry in operational/moistened state A 0.094 W/m*S). 3 layer(item 4) - 10mm ( SuperThermo30) light cement-perlite mixture between the ceramic block masonry and the facing masonry (density 200 kg/m3, thermal conductivity coefficient at operating humidity less than 0.12 W/m*C). 4 layer(item 5) – 120mm wall masonry using slotted facing bricks (thermal conductivity coefficient of masonry in operational condition is 0.45 W/m*C. Pos. 3 - warm masonry mortar pos. 6 - colored masonry mortar.

Let's consider the masonry of an external wall, using foam blocks, with mineral wool insulation, lined with ceramic hollow bricks. For the option of using foam blocks, the total wall thickness excluding the plaster layer is 510mm (300mm gas silicate block D500 + 50mm mineral wool insulation + 40mm ventilation gap + 120mm facing masonry). 1 layer(no number) – 20mm heat-insulating cement-perlite plaster (thermal conductivity coefficient 0.18 W/m*C). 2 layer(item 4) – 300mm wall masonry using foam block 500kg/m 3 (thermal conductivity coefficient of masonry in operational condition 0.123 W/m*S, given value taken from the test report for the thermal conductivity of gas silicate Ytong block D500, a test report for the thermal conductivity of foam block masonry could not be found). 3 layer(item 3) – 50mm mineral wool insulation (thermal conductivity coefficient in operational condition 0.045 W/m*C). 4 layer(item 1) – 120mm wall masonry using slotted facing bricks (thermal conductivity coefficient of masonry in operational condition is 0.45 W/m*C. * – the layer of facing bricks is not taken into account in the calculation of the thermal resistance of the structure, because according to the technology of laying walls with insulation, the facing masonry is carried out with the device ventilation gap, and ensuring free air circulation in it. This required condition to ensure the standard humidity of the structure, and first of all, the insulation.

We calculate the conditional thermal resistance R 0 for the structures under consideration.

Kerakam Kaiman 30

R 0 Cayman30 =0.020/0.18+0.300/0.094+0.01/0.12+0.12/0.45+0.158=3.81 m 2 *S/W

D500 with 50mm insulation

R 0 =0.020/0.18+0.300/0.123+0.05/0.045+0.158=4.21 m 2 *S/W

We consider the reduced thermal resistance R r 0 of the structures under consideration.

The design of the external wall in which the block is used Kerakam Kaiman 30

R r 0 Cayman30 =3.81 m 2 *S/W * 0.98 = 3.73 m 2 *S/W

The design of the external wall in which a gas silicate block is used D500(500kg/m3) with a 50mm layer of mineral wool thermal insulation.

R r 0 D500=4.21 m 2 *S/W * 0.98 = 4.13 m 2 *S/W

The reduced thermal resistance of the two structures under consideration is higher than the required thermal resistance for the city of Moscow, which means that both structures satisfy SNiP “Thermal protection of buildings” for the city of Moscow (2.9929 m 2 *C/W .