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How to insulate between a brick and a block. External three-layer stone wall with brick facing. Construction of a three-layer wall with brick cladding

The use of foam as a heater for exterior walls by some federal normative documents not limited. However, there is Order No. 18 of the Minmosoblstroy of May 23, 2008 “On the use of three-layer wall enclosing structures with an inner layer of slab effective insulation and a front layer of brickwork during the construction of civil buildings on the territory of the Moscow region.
This order of the Ministry of Mosoblstroy states that those used in last years during the construction of frame-monolithic multi-storey residential buildings, three-layer external wall structures with an inner layer of slab effective insulation and a front layer of brickwork have significant damage in a significant number of buildings in operation. As a rule, design flaws are revealed during the operation of buildings and it is practically impossible to eliminate construction defects by the forces of operating organizations.
The air exchange process through the outer walls - "the breathing of the walls", is a natural and inevitable physical process of the release of moisture in the form of steam from inside the house to the outside. And if the layers of the “pie” of the wall have different vapor permeability, while the outer ones are less than the inner ones, as is the case with foam plastic and aerated concrete blocks, then there is nowhere to get moisture due to the different throughput of materials. As a result, it accumulates in the form of condensate at the boundary of such a vapor permeability difference. And if the outer facing layer is thin enough, and the inner one, on the contrary, is thick so that in severe cold the temperature at the place of condensate accumulation is less than zero, then this leads to freezing of moisture inside the material, which in turn leads to loss of thermal insulation properties and destruction of the insulation.
In addition, the accumulation of moisture in the wall can also affect the microclimate in the premises of the house. Since a wet wall does not benefit any comfortable microclimate.
In order to prevent possible negative consequences the use of such solutions in building envelopes is prohibited by the Ministry of Mosoblstroy municipalities In the Moscow region, developers, design and contractor organizations should use three-layer wall enclosing structures with an inner layer of slab effective insulation and a front layer of brickwork when designing buildings and structures in the Moscow region.
Such are the unfortunate things for polystyrene and other slab effective heaters based on it when used for thermal insulation of external walls in three-layer wall enclosing structures. However, it remains possible to use these materials in ventilated facade systems.
Of course, it is possible to use three-layer wall enclosing structures in private housing construction. It should only be taken into account that the front brickwork in this case will only perform the function in the ventilated facade system. exterior finish and is derived from the thermal insulation calculation.

Hello!

When answering the question, I will use the information you provide in the posts below and in your question.

What thickness of insulation is needed. The calculation shows that to ensure resistance to heat transfer R = 2.4, the thickness of the foam is -25 mm. For R= 2.2, thickness 13 mm. If we round the obtained thicknesses to those that are on the market, then these are, respectively, 30mm and 20mm foam. You can take both ordinary foam and extruded polystyrene foam (EPS). In terms of durability (in this design), no difference was noticed in practice. EPPS - it is better to take 35 kg \ m3, the thicknesses for it are the same as for polystyrene. Styrofoam must be taken with a density of at least 25 kg / m3. The thickness of the foam (or EPPS), obtained by calculation, 30mm and 20mm, is quite inconvenient during the work itself. Usually, external insulation (with subsequent plastering) is carried out when the thickness of the insulation is from 50 mm and above. The fact is that a sheet of foam (and EPPS), 30 mm thick, and even more so 20 mm, is quite fragile. But it must not only be glued to the wall, but also nailed with dowels (6 pieces per sheet).
As for the glue. A prerequisite is that the glue is special for gluing polystyrene foam (or extruded polystyrene foam). Considering that all the same, the glue is "duplicated" with dowels, then, in principle, it does not matter what brand the glue is.
To reinforce the corners, there are special plastic corners with a reinforcing mesh.
As for the thermals. Here the situation is as follows: both polystyrene and EPPS come with a smooth edge, and "with a quarter". That is, the sheets adjoin each other either exactly, or go one on top of the other. As far as I know, in thicknesses of 20 and 30 mm, only a smooth edge is produced. When using insulation "with a quarter", the seams are cut by the installers themselves with a certain step of 2-3 m. When using insulation with a smooth edge, its joints are thermal seams, they do not need to be specially made.
I recommend an article on warm plaster, it describes what you are asking about. As a conclusion, I can say that insulation with warm plaster is more expensive than conventional insulation.

Conclusion for your home as a whole. Considering that you will insulate the attic floor (through which there were the most significant heat losses), and the fact that the thickness of the missing wall insulation is only 20-30mm, we can advise the following. Insulate the attic this year, and see how much more comfortable it becomes during this summer and winter. If normal, then the walls, in principle, may not be touched. If it continues to be cold in winter (or hot in summer), then arrange facade work, and it is possible to take the thickness of the foam 40mm, so that it is more convenient to mount it.

The problem with heat loss in residential buildings always exists, somewhere it seeps through the roof, somewhere through the foundation, but most often heat is lost through the walls. Actual question- how to avoid these losses, because because of this you have to spend more on electricity, forcing the heating equipment to work for wear and tear?

The answer is simple, competently insulate the facade walls. And about how and how to do it, you will learn from our article.

Characteristic features of brick walls

Building bricks are very different in their characteristics from concrete blocks or wooden beams:

The walls can be made of both hollow and hollow. It all depends on various factors: load on the foundation, average temperatures in the region, thermal insulation materials used.
You can also lay bricks in two types: solid (the most common and easiest way) and well (with an air pocket that is filled with insulation). For example, there may be a heater between the foam block and the brick, where the brick is the front side.

Reinforced sound insulation is not required for brickwork, the material itself prevents the ingress of extraneous sounds into the room.

As for the rest Construction Materials are similar, all walls can be insulated both from the outside and from the inside. The combined method - not everyone can afford thermal insulation from all sides, and the usable area is significantly reduced.

Types of thermal insulation materials

If you decide to build brick walls with insulation, then this section will help you decide which one.

Price in this case, is not taken into account, the comparison takes place only according to the technical characteristics:

Mineral wool- one of the most popular materials that has been used for many decades. It has a fairly low thermal conductivity coefficient (within 0.041 - 0.044 W / (m * K)), while a good compression density indicator (from 20 kg / m3 to 200 kg / m3). Of the shortcomings - high moisture absorption, not like a sponge, but inferior to other materials.
Styrofoam (expanded polystyrene)– also has a high demand, due to resistance to high humidity. With a coefficient of thermal conductivity slightly lower than that of mineral wool, but strength (compressive density) suffers, the material is easily damaged. Plus, if it is exposed to fire, it will emit acrid smoke.
Extruded polystyrene foam- is considered an ideal option, both for internal work and for external. It does not emit toxic fumes, has the lowest thermal conductivity threshold of solid thermal insulation materials, but also suffers from “brittleness”.

Note! It, like polystyrene, is easy to mount with your own hands; this does not require special equipment or any special knowledge. We will tell you more about the process of insulating brick walls a little later.

Expanded clay- bulk material, which has excellent performance in terms of thermal conductivity, vapor barrier, but is more often used to insulate the floor or ceiling. Although, just for well masonry, it fits perfectly.

Warm plaster- another material, only already liquid. As regards any specifications, then the plaster is slightly inferior to other options for thermal insulation. However, there is one advantage - saving usable space, it can be applied directly to a brick wall (on a reinforcing mesh).

These are not all materials, but we have described only the most popular and practical. And about how the insulation is fastened to brick wall(we will take the double silicate brick M 150 as the basis of the house), we will tell in the next section.

Thermal insulation of the house from the outside

Consider the process of insulation using the example of foam, which can be used in any conditions, when, as a mineral wool, it is effective only when warmed from the inside:

The first step is to prepare the wall: close up all the cracks, cover up the crumbling seams of the brickwork.
Install the crate using wooden blocks. The peculiarity of this process is uprights it is better to maintain a distance equal to the width of the foam, so there will be fewer joints.
Cut the material to length.
Prepare an adhesive base or dish-shaped nails for fixing the insulation.

For your information! There is not much difference, each mounting option is good in its own way, only one is considered dirty (you need to drill under the nails), and the second is clean. There you just need to smear thick glue and that's it.

Fix the heat-insulating layer by sealing all joints and cracks with mounting foam.

Cover with a windproof membrane on top, using a furniture stapler as fasteners.
Now it remains to choose the finishing material and revet the house.

As you can see, the instructions for installing the insulation from the street side do not require any special skill. That is why you can easily save on the construction team by doing all the work on your own.

Thermal insulation of the house from the inside

This process is slightly, but different from the above. Here, in fact, what are the differences:

A waterproofing film is necessarily attached under the insulation, which does not allow moisture to enter the surface of the heat-insulating material. It is especially relevant in the case of the mineral wool option.
If a crate is required on the street side, then in the premises, finishing materials can be mounted directly on the insulation, of course, if solid material is used. To do this, it is necessary to level the surface, close up all the cracks and use a reinforcing mesh.
When insulating a house from the inside, it is worth taking care in advance of isolating communications in the walls, this, at a minimum, requires safety precautions.

Advice! For wiring, use plastic corrugated pipes, reliable and durable "protectors".

We considered options when brick walls with insulation interact directly, a solid version of thermal insulation. Now let's take a closer look at the well masonry.

two walls

Let's take for example the case when it is required to fix the insulation between the brick and the foam block. Let's break it down into several steps:

First of all, the outer wall is laid out. It is laid in accordance with the rules for working with bricks, with the exception of one moment - every 4-5 horizontal rows it is necessary to insert a metal pin into the solution. This is the connecting element of the two walls.

Note! An ordinary wire with a diameter of about 5 mm is enough. In terms of length, it must be taken into account that the pin is recessed by 2-3 cm in the first masonry and the same in the second.

The next step is to install the heater. If it is polystyrene foam, then it can be fastened directly through the wire, using it as a supporting element. For rolled materials, it is better to use an adhesive base, at worst, fix it with dish-shaped nails.

Important! For bulk material, such as expanded clay, you must first build both walls: external and internal. After that, for example, the insulation between the brick and the block is filled up, carefully compacted.

The last stage is construction inner wall. The peculiarity of the process is that the wire is fastened between the bricks, in the solution. Some experts advise using a windproof film over a thermal insulation material. In fact, with quality work performed, it will be superfluous.

As for brickwork, it all depends, of course, on your skill, but we advise you to build walls in sequence. For example, you built a 1-1.5 meter outer wall, fix the insulation and build an inner wall. Then return to the outside again.

For your information! With such construction, all joints of heat-insulating materials must be sealed, you can use adhesive tape or mounting foam.

Features of insulation

Insulation is different for insulation, it is necessary to choose according to the weather conditions in your region and various effects on the material.
If funds allow (this is not the biggest cost item), use two types of fastening: an adhesive base, for fixing around the perimeter, and nails. This will eliminate the likelihood of subsidence and collapses of heat-insulating materials.
The joints of mineral wool insulation must be isolated from moisture and wind, for this you can use various materials, normal tape will do.
In some cases (without the use of facing bricks), the surface of the wall for insulation is primed and leveled. The process, although costly, allows you to increase the efficiency of any insulation.
In different regions, the temperature in winter may vary, it may happen that your temperature does not drop below -15 degrees, then the use of heaters can become controversial issue. If only because it would be a waste of money.

Output

The use of thermal insulation materials should be accompanied not by simple “I want” and “I can”, but by clear information about whether it will be effective and useful. In any case, even if insulation is laid between the block and the brick, it is necessary to understand how much it saves heating costs and how long the work will pay off.

Exterior decoration of houses made of aerated concrete blocks with bricks is very popular these days. A building that is built from this material, and then lined with brickwork, is much cheaper than a completely brick building, while the view becomes modern, more aesthetic and status with the least investment. But is it only a matter of external attractiveness?

Advantages and disadvantages of facing an aerated concrete wall with a brick

Let us consider in detail the advantages and disadvantages that facing aerated concrete with bricks has.

Advantages

Soundproofing.
visual aesthetics.
Strengthening the building.
Service life extension.

disadvantages

If the masonry is not installed correctly, condensation may accumulate in the wall cavity.
Additional costs for construction and materials.

A consumable article is expected in any case when lining a building, while aerated concrete blocks are one of the most inexpensive and stable structures. According to Engineering and Construction Journal No. 8 (2009), after conducting serious tests for the strength and durability of an aerated concrete wall with brick cladding in 2009 in St. Petersburg, it turned out that the life of such a wall varies from 60 to 110 years or more. A single climatic zone and material of the same quality was considered.

A house made of aerated concrete lined with bricks can have a service life that differs by almost half.

Why such a difference in strength and wear resistance? It turned out that the matter was the presence of a gap and ventilation between the base of the gas blocks and the brick lining.

What are the ways of facing a gas block with bricks

The gas block wall can be lined in several ways. This refers to the distance between the brick and the aerated concrete block, as well as the presence of heaters, if there is a gap between the wall and the cladding. Let's consider each of them in detail.

Dense masonry without gaps and ventilation

The danger of early destruction appears when it is planned to use a heated room. That is, the temperature difference inside and outside the house will significantly reduce the life of such a building. When the room is heated from the inside, water vapor will begin to move through the porous aerated concrete to the outside. In the absence of a gap or insulation, they will accumulate between the gas block and the brick, destroying both materials. In this case, the condensate accumulates unevenly, which accelerates the process of decomposition and deformation of the structure of the gas block. The most cost-effective will be the use of external insulation in the form of mineral wool or wet plaster finish. A similar finishing of aerated concrete with bricks (without a gap) applies only to unheated buildings.

Brick laying at a distance from gas blocks without ventilation

In the rules of SP 23-101-2004 (Design of thermal protection of buildings) there is a prescription on the principle of arranging layers between the wall and the surface of the cladding, which states that the closer to the outer layer of the wall, the lower the vapor permeability of the material should be. In accordance with paragraph 8.8, layers with greater thermal conductivity and vapor permeability should be located closer to the outer surface of the wall. British experts after a series of studies explained that it is necessary to arrange the layers so that the vapor conductivity to the outer layer increases with a difference of at least 5 times from the inner wall. If this cladding method is chosen, then according to the rules of paragraph 8.13, the thickness of the non-ventilated gap must be at least 4 cm, while it is recommended that the layers be separated by blind diaphragms of non-combustible material into zones of 3 m each.

Finishing aerated concrete with bricks with a ventilated space

This method of cladding is the most rational in terms of the technical characteristics of the materials and the durability of the structure. However, the construction of such a structure must be carried out according to certain rules (SP 23-101-2004 clause 8.14).

Consider how to overlay a house made of aerated concrete with a brick with a ventilated gap between the masonry in accordance with all the rules. The air space must be at least 6 cm thick, but not more than 15 cm thick. Wherein the aerated concrete wall itself serves as thermal insulation. If the number of storeys of the building is higher than three, then perforated partitions are placed in the gaps (1 time per 3 floors) to cut the air flow. There must be through ventilation holes in the brickwork, the total area of which is determined by the principle: per 20sq.m area 75sq.cm holes. At the same time, the holes located below are made with a slight slope outward to drain condensate from the wall cavity.

In that case, if you plan to insulate the aerated concrete wall additionally to the air gap, then for this purpose heat-insulating materials are used, the density of which is not less than 80-90 kg / m 3. The side of the insulation in contact with the air layer must have an air-protective film on the surface (Izospan A, AS, Megaizol SD and others) or another air-protective shell (fiberglass, glass mesh, basalt wool). It is not recommended to use ecowool and glass wool as a heater, as these materials are too soft and not dense enough. It is also not allowed to use foam and XPS due to their flammability and vapor barrier characteristics. When facing walls made of aerated concrete with bricks with additional insulation on gas blocks, soft, loose, combustible materials are not used. The vapor conductivity of these materials must be sufficiently high to avoid the formation of condensate.

Summing up

So, what conclusions can be drawn about the methods of facing aerated concrete walls with bricks? For convenience, we summarize the features of each cladding method in a table:

Characteristics	Cladding without gap	Gap cladding without ventilation	Cladding with ventilated gap
Brickwork	+	+	+
Protection of an aerated concrete wall from external influences	+	+	+
thermal insulation	Insignificant increase	Increase (resistance of brickwork), decrease (moisture content of the aerated concrete wall increases)	No increase (ventilation of space between walls)
Terms of operation, destruction of the building	There is a reduction in the period of use by 60%.	Shrinkage due to humidity and condensation.	No reduction or increase due to lack of condensation and controlled air circulation.
Construction costs	The costs of the foundation, expansion (up to 15 cm), brick, mortar, flexible connections are increasing.	The costs for the foundation, expansion (up to 19 cm), brick, mortar, flexible connections are increasing.	The costs for the foundation, expansion (up to 21 cm), brick, mortar, flexible connections are increasing.
Profitability and expediency	Economically disadvantageous due to reduced thermal insulation and service life.	No special benefit in most cases. It is advisable only in an even temperate climate that does not require heating of the building from the inside.	It is not economically profitable, but it is advisable if brick cladding is required on the outside of heated buildings.

Thus, by lining an aerated concrete wall with bricks, it will not be possible to significantly save on materials, and it will also not work to increase thermal insulation. The only positive aspects - respectable appearance and an increase in service life, but this is achieved subject to the proper organization of construction processes, the use of materials and technologies recommended by SP 23-101-2004.