Insulation between brick and wall. Brick insulation - the secrets and nuances of proper finishing

The use of foam as insulation for external walls by some federal regulatory documents not limited. However, there is an Order No. 18 of the Ministry of Regional Construction dated 05.23.2008 “On the use of three-layer wall enclosing structures with an inner layer of effective slab insulation and face layer from brickwork during the construction of civil buildings on the territory of the Moscow region ”.
This order of the Ministry of Moscow Region Construction states that the last years during the construction of frame-monolithic multi-storey residential buildings, three-layer external wall structures with an inner layer of effective slab insulation and a facing layer of brickwork have significant damage on a significant number of buildings in use. As a rule, design flaws are revealed during the operation of buildings and the elimination of construction defects by the forces of operating organizations is practically impossible.
The air exchange process through the outer walls - "wall breathing", is a natural and inevitable physical process of moisture release in the form of steam from inside the house to the outside. And if the layers of the "cake" walls have different vapor permeability, while the outer ones are less than the inner ones, as is the case with foam and aerated concrete blocks, then such moisture has nowhere to go due to different bandwidth materials. As a result, it accumulates in the form of condensate at the border of such a difference in vapor permeability. And if the outer facing layer is thin enough, and the inner one, on the contrary, is thick so that in extreme cold weather 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 a loss thermal insulation properties and the destruction of insulation.
In addition, the accumulation of moisture in the wall can also affect the microclimate in the premises of the house. Insofar as wet wall no comfortable microclimate is good for it.
In order to prevent possible negative consequences of use similar decisions in the enclosing structures Minmosoblstroy prohibits municipalities Of the Moscow Region, developers, design and contracting organizations, when designing in the territory of the Moscow Region for buildings and structures, three-layer wall enclosing structures with an inner layer of effective slab insulation and a facing layer of brickwork.
Such are the sad things for foam and other plate effective insulation on its basis when using them for thermal insulation of external walls in three-layer wall enclosing structures. However, it remains possible to use these materials in ventilated facade systems.
It is certainly possible to use three-layer wall enclosing structures in private housing construction. Just keep in mind that the front brickwork in this case, it will perform only the function of external decoration in the ventilated facade system and is deduced from the thermal insulation calculation.

Hello!

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

1. What is the thickness of the insulation 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 the obtained values ​​of the thicknesses are rounded to those that are on the market, then these are, respectively, 30mm and 20mm of foam. You can take both regular foam and extruded polystyrene foam (EPS). In terms of durability (in such a 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 the foam. Polyfoam must be taken with a density of at least 25 kg / m3. The thickness of the foam (or EPS) obtained by calculation, 30mm and 20mm, is quite inconvenient when carrying out the work itself. Usually, external insulation (followed by plastering) is carried out when the thickness of the insulation is from 50mm and above. The fact is that a sheet of foam (and EPS), 30mm thick, and even more so 20mm, is quite fragile. But it needs not only to be glued to the wall, but also to be nailed with dowels (6 pieces per sheet).
2. As for the glue. A prerequisite is that there is a special glue 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 which company the glue is.
3. To strengthen the corners, there are special plastic corners with reinforcing mesh.
4. As for the thermal seams. Here the situation is as follows: both polystyrene and EPS is with an even edge, and "with a quarter". That is, the sheets adjoin each other or evenly, or overlap one another. As far as I know, in thicknesses of 20 and 30 mm, only a flat 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.
5. On warm plaster, I recommend the article, it describes what you are asking about. As a conclusion, I can say that the insulation warm plaster more expensive than conventional insulation.

Conclusion for your home as a whole. Considering that you will insulate 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, then we can advise the following. Insulate the attic this year, and see how much more comfortable it will become 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 plastic 40mm, so that it is more convenient to mount it.

Heat loss problem in residential buildings it always exists, somewhere it seeps through the roof, somewhere through the foundation, but most often heat is lost through the walls. An urgent question is how to avoid these losses, because because of this you have to spend more on electricity, forcing heating equipment work hard?

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

Characteristics of brick walls

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

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

• For brickwork, no enhanced sound insulation is required; the material itself quite well prevents the ingress of extraneous sounds into the room.

Otherwise Construction Materials are similar, all walls can be insulated both from the outside and from the inside. The combined method - thermal insulation from all sides is not affordable for everyone, and the useful 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.

The price in this case is not taken into account, the comparison is made only by technical characteristics:

• Mineral wool Is one of the most popular materials that has been used for many decades. It has a rather low coefficient of thermal conductivity (in the range of 0.041 - 0.044 W / (m * K)), while good indicator compression density (from 20 kg / m3 to 200 kg / m3). Among the disadvantages is high moisture absorption, not like a sponge, but inferior to other materials.
• Styrofoam (expanded polystyrene)- also in high demand, due to resistance to high humidity... When the thermal conductivity coefficient is slightly lower than that of mineral wool, but the strength (compression density) suffers, the material is easily damaged. Plus, if exposed to fire, it will emit corrosive smoke.
• Extruded polystyrene foam- counts ideal option, as for internal works and for external ones. Does not emit toxic vapors, has the lowest thermal conductivity threshold of solid thermal insulation materials, but also suffers from "fragility".

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

• Expanded clay- a bulk material that has excellent thermal conductivity and vapor barrier performance, but is more often used for floor or ceiling insulation. Although, just for well masonry, it fits perfectly.

• Warm plaster- another material, only already liquid. Regarding any technical characteristics, 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 ones. And how the insulation is fastened to brick wall(we take as the basis of the house a double silicate brick M 150), we will tell in the next section.

Thermal insulation of the house 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 for insulation from the inside:

• The first step is to prepare the wall: to close up all the cracks, to cover up the crumbling seams of the brickwork.
• Install the crate using wooden blocks... Peculiarity this process- between vertical posts 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 plate nails for attaching the insulation.

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

• Anchor thermal insulation layer, sealing all joints and cracks with polyurethane 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 instruction for installing insulation from the street side does not require special skill. That is why you can easily save on construction crew, having done all the work on their own.

Thermal insulation of the house from the inside

This process is insignificant, but differs from the above. Here, in fact, are the differences:

• A waterproofing film must be attached under the insulation, which does not allow moisture to get onto 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 Decoration Materials can be attached directly to the insulation, of course, if a solid material is used. To do this, it is necessary to level the surface, fill 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 least, 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

Take, for example, the case when you want to fix the insulation between the brick and the foam block. Let's break it down into several stages:

• The first step is to lay out the outer wall. It is laid according to 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! A common wire with a diameter of about 5 mm is sufficient. In terms of length, it is necessary to take into account that the pin is recessed by 2-3 cm in the first laying and the same amount in the second.

• The next step is to install insulation. If it is expanded polystyrene, then it can be fixed directly through the wire, using it as a supporting element. For roll materials it is better to use an adhesive base, at worst - to fix it with disc nails.

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

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

As for the brickwork, it all depends, of course, on your skill, but we advise you to build the walls consistently. For example, they built 1-1.5 meters outer wall, fix the insulation and build the inner wall. Then go back to the outside again.

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

Features of insulation

• Insulation to insulation is different, it is necessary to choose in accordance with the weather conditions in your region and the various influences on the material.
• If allowed cash(this is not the biggest cost item) use two types of fasteners: an adhesive base, for fixing around the perimeter, and nails. This will eliminate the likelihood of subsidence and collapse of thermal insulation materials.
• The joints of mineral wool insulation must be insulated from moisture and wind, for this you can use various materials, ordinary scotch tape will do.
• In some cases (without using facing bricks), the wall surface for insulation is primed and leveled. The process, although costly, allows you to increase the efficiency of any insulation.
• V different regions the temperature in winter can vary, it may happen that your temperature does not drop below -15 degrees, then the use of heaters can become a controversial issue. If only because it will be an extra waste of money.

Output

The use of thermal insulation materials should not be accompanied by simple "want" and "can", but rather 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.

Three-layer wall structure with brick cladding

In low-rise construction, the design of an external three-layer wall is very popular: the load-bearing wall is a brick cladding insulation (120 mm), Fig. 1... Such a wall allows you to use effective for each layer materials.

Bearing wall made of bricks or concrete blocks, is the structural frame of the building.

Insulation layer... mounted on the wall, provides the required level of thermal insulation outer wall.

Wall cladding from facing brick protects the insulation from external influences and serves decorative coating walls.

Fig. 1. Three-layer wall.
1 — interior decoration; 2 - load-bearing wall; 3 - thermal insulation; 4 - ventilated gap; 5 - brick cladding; 6 - flexible connections

Multi-layer walls also have disadvantages:

• limited durability of the insulation material in comparison with the material of the load-bearing wall and cladding;
• highlighting dangerous and harmful substances from insulation, albeit within the permissible limits;
• the need to use special measures to protect the wall from blowing and moisture - vapor-tight, windproof coverings and ventilated gaps;
• flammability of polymer insulation;

Load-bearing wall in three-layer masonry

Insulation of the walls of the house with mineral wool slabs

Mineral wool slabs are fixed on the load-bearing wall with a ventilated air gap between the surface of the slabs and the brick cladding, or without a gap, Fig. 1.

The calculations of the humidity regime of the walls show that in three-layer walls condensation in the insulation falls in the cold season in almost all climatic zones of Russia.

The amount of condensate that falls out is different, but for most regions it fits into the norms established by SNiP 23-02-2003 "Thermal protection of buildings". Condensation does not accumulate in the wall structure during the year-round cycle due to drying in warm time year, which is also a requirement of the specified SNiP.

As an example, the figures show graphs of the amount of condensate in the insulation based on the results of calculations for different options cladding of three-layer walls of a residential building in St. Petersburg.

Rice. 2. The result of calculating the humidity regime of the wall with mineral wool insulation as a middle layer (expanded clay concrete - 250 mm, insulation -100 mm, brick -120 mm). Facing - ceramic brick without ventilation gap.

Rice. 3. The result of calculating the moisture regime of a wall with mineral wool insulation with a plaster coating (expanded clay concrete - 250 mm, insulation - 120 mm, plaster coating -10 mm). Cladding - vapor permeable.

Rice. 4. The result of calculating the moisture regime of a wall insulated with mineral wool slabs with a ventilated gap and a "siding" -type coating (brick - 380 mm, insulation -120 mm, siding). Cladding - ventilated facade.

The graphs clearly show how the cladding barrier, which prevents ventilation of the outer surface of the mineral wool insulation, leads to an increase in the amount of condensate in the insulation. Although in the annual cycle, moisture does not accumulate in the insulation, but when facing with a brick without a ventilation gap in the insulation annually in winter condenses and freezes a significant amount of water, Fig. 2... Moisture also accumulates in the layer adjacent to the insulation brick cladding

Moistening the insulation reduces its heat-shielding properties, which increases heating costs building.

In addition, water annually, when freezing, destroys the insulation and the brickwork of the cladding. Moreover, the cycles of freezing and defrosting during the season can occur repeatedly. The insulation gradually crumbles, and the brickwork of the cladding collapses. Note that frost resistance ceramic brick only 50 - 75 cycles, and the frost resistance of the insulation is not standardized.

Replacing insulation, covered with brick cladding, is an expensive pleasure. More durable in these conditions are hydrophobized high-density mineral wool boards. But these plates also have a higher cost.

The amount of condensation is reduced or no condensation at all if provide better ventilation insulation surface - fig. 3 and 4.

Another way to eliminate condensation is to increase the resistance to vapor permeation of the load-bearing wall. For this, the surface of the load-bearing wall is covered vapor barrier film or use thermal insulation boards with vapor barrier applied to their surface. When mounted on a wall, the surface of the slabs covered with a vapor barrier must face the wall.

The device of a ventilated gap, sealing walls with vapor-tight coatings complicates and increases the cost of the wall structure. What does the moistening of the insulation in the walls in winter lead to is written above. So choose. For construction areas with harsh winter conditions a ventilated gap arrangement can be economically viable.

In walls with a ventilated gap, mineral wool slabs with a density of at least 30-45 are used kg / m 3, glued on one side with a windproof coating. When using slabs without wind protection on the outer surface of the thermal insulation, windproof coverings should be provided, for example, vapor-permeable membranes, fiberglass, etc.

In walls without a ventilated gap, it is recommended to use mineral wool boards with a density of 35-75 kg / m 3... In a wall structure without a ventilated gap, thermal insulation boards are installed freely in a vertical position in the space between the main wall and the facing brick layer. As support elements for the insulation there are fasteners provided for fastening the brick cladding to the bearing wall - reinforcing mesh, flexible connections.

In a wall with a ventilation gap, insulation and a windproof covering are attached to the wall using special dowels at the rate of 8-12 dowels per 1 m 2 surface. The dowels must be buried in the thickness concrete walls at 35-50 mm, brick - by 50 mm, in the masonry of hollow bricks and lightweight concrete blocks - by 90 mm.

Wall insulation with expanded polystyrene or foam

Rigid foam boards are placed in the middle of a three-layer brick wall structure without a ventilated gap.

Polymer boards have a very high vapor permeability resistance. For example, a layer of wall insulation made of expanded polystyrene (EPS) plates has a resistance 15-20 times greater than that of a brick wall of the same thickness.

Insulation, when sealed, is a vapor barrier in a brick wall. Steam from the room simply does not get onto the outer surface of the insulation.

With the correct thickness of the insulation, the temperature of the inner surface of the insulation should be above the dew point. When this condition is met, steam condensation on the inner surface of the insulation does not occur.

Mineral insulation - low density aerated concrete

V recent times Another type of insulation is gaining popularity - products made of low-density aerated concrete. These are heat-insulating plates based on materials already known and used in construction - autoclaved aerated concrete, gas silicate.

Thermal insulation boards made of aerated concrete have a density of 100 - 200 kg / m 3 and the coefficient of thermal conductivity in a dry state 0.045 - 0.06 W / m about K... Mineral wool and expanded polystyrene insulation have approximately the same thermal conductivity. Slabs are produced with a thickness of 60 - 200 mm... Compressive strength class B1.0 (compressive strength not less than 10 kg / m 3.) Vapor permeability coefficient 0.28 mg / (m * year * Pa).

Aerated concrete thermal insulation boards are a good alternative to mineral wool and expanded polystyrene insulation.

Known on construction market trade marks thermal insulation boards from cellular concrete: "Multipor", "AEROC Energy", "Betol".

Advantages of aerated concrete thermal insulation slabs:

The most important is higher durability. The material does not contain any organic matter - it is fake diamond... Has a fairly high vapor permeability, but less than mineral wool insulation.

The structure of the material contains a large number of open pores. The moisture that condenses in the insulation in winter dries quickly in the warm season. No moisture build-up occurs.

Thermal insulation does not burn, does not emit under the influence of fire harmful gases... The insulation does not cake. Insulation plates are harder and mechanically more durable.

The cost of facade insulation with cellular concrete slabs, in any case, does not exceed the cost of thermal insulation with mineral wool insulation or expanded polystyrene.

When installing thermal insulation plates made of aerated concrete, the following rules are followed:

Thermal insulating slabs made of aerated concrete up to 100 mm fastened to the facade with glue and dowels, 1-2 dowels per slab.

From plates with a thickness of more than 100 mm a wall is laid out close to the wall to be insulated. The laying is carried out on glue with a seam thickness of 2-3 mm... WITH load-bearing wall masonry made of insulation plates is connected with anchors - flexible ties at the rate of five ties per 1 m 2 walls. A technological gap of 2-15 can be left between the load-bearing wall and the insulation. mm.

It is better to tie all layers of the wall and brick cladding with a masonry mesh. This will increase mechanical strength walls.

Wall insulation with foam glass

Three-layer wall of the house with foam glass insulation and brick cladding.

Another type of mineral insulation that has appeared on the construction market relatively recently is foam glass plates.

Unlike heat-insulating aerated concrete, foam glass has closed pores. Due to this, foam glass slabs poorly absorb water and have low vapor permeability. A ventilated gap between the insulation and the cladding is not required.

The foam glass insulation is durable, does not burn, is not afraid of moisture, is not damaged by rodents. Has a higher cost than all of the above types of insulation.

Installation of foam glass plates on the wall is carried out using glue and dowels.

The thickness of the insulation is chosen in two stages:

1. They are chosen based on the need to provide the required resistance to heat transfer of the outer wall.
2. Then a check is made for the absence of steam condensation in the thickness of the wall. If the check shows otherwise, then it is necessary to increase the thickness of the insulation. The thicker the insulation, the less the risk of steam condensation and moisture accumulation in the wall material. But, this leads to an increase in construction costs.

An especially large difference in the thickness of the insulation, selected according to the above two conditions, occurs when insulating walls with high vapor permeability and low thermal conductivity. To ensure energy saving, the thickness of the insulation is relatively small for such walls, and to avoid condensation, the thickness of the slabs must be unreasonably large.

When insulating aerated concrete walls(as well as from other materials with low resistance vapor permeability and high resistance to heat transfer - for example, wooden, from large-porous expanded clay concrete), the thickness of the polymer thermal insulation, according to the calculation of moisture accumulation, turns out to be much greater than it is necessary according to the standards for energy saving.

To reduce the steam intake, it is recommended to arrange vapor barrier layer on the inner surface of the wall(from the side of a warm room), Rice. 6. For the device of a vapor barrier from the inside, materials with a high resistance to vapor permeation are chosen for finishing - a deep penetration primer is applied to the wall in several layers, cement plaster, vinyl wallpapers.

A vapor barrier device from the inside is mandatory for walls made of aerated concrete, gas silicate for any type of insulation and facade cladding.

It should be borne in mind that the masonry of the walls of a new house always contains a large amount of construction moisture. Therefore, it is better to allow the walls of the house to dry well outside. It is recommended to carry out work on the insulation of the facade after the interior decoration is completed, and not earlier than a year after the end of this work.

Facing the exterior walls of the house with bricks

Cladding the exterior walls of the house with bricks is durable and, when using special colored facing bricks, and even better clinker brick... quite decorative. The disadvantages of cladding include the relatively large weight of the cladding, the high cost of special bricks, and the need to broaden the foundation.

It should be especially noted the complexity and high cost of dismantling the cladding to replace the insulation. The service life of mineral wool and polymer insulation does not exceed 30 - 50 years. At the end of its service life, the heat-saving properties of the wall are reduced by more than a third.

With brick cladding, use the most durable insulation, providing them in the construction of the wall conditions for maximum long-term work without replacement (minimum amount of condensation in the wall). It is recommended to choose high-density mineral wool insulation and polymer from extruded polystyrene foam, EPS.

In the walls with brick cladding, in It is most advantageous to use mineral insulation made of autoclaved aerated concrete or foam glass, with rock service which is much more than mineral wool and polymer.

Brick cladding is laid in half a brick, 120 mm. on ordinary masonry mortar.

A wall without a ventilated gap, insulated with high-density slabs (mineral wool - more than 50 kg / m 3, EPS), you can veneer with brickwork on the edge - 60 mm. This will reduce the overall thickness of the outer wall and base / plinth.

Brick cladding masonry is bonded to the load-bearing wall masonry steel wire or reinforcing mesh, protected from corrosion, or special flexible connections (fiberglass, etc.). The grid or ties are placed vertically with a step of 500-600 mm.(height of the insulation plate), horizontally - 500 mm., while the number of bonds per 1 m 2 blank walls - at least 4 PCS. At the corners of the building along the perimeter of the window and doorways 6-8 PCS. by 1 m 2.

The masonry of the brick cladding is reinforced longitudinally with a masonry mesh with a vertical step of no more than 1000-1200 mm. Masonry mesh should go into the seams of the masonry of the load-bearing wall.

For ventilation air gap in the bottom row facing masonry arrange special vents at the rate of 75 cm 2 for every 20 m 2 wall surface. For bottom vents, a slot brick can be used, placed on an edge so that outside air can penetrate through the holes in the brick air gap in the wall. The upper air vents are provided in the eaves of the wall.

Vents can also be made by partial filling cement mortar vertical joints between the bricks of the lower row of masonry.

Placing a window and a door in the thickness of a three-layer wall should ensure minimal heat loss through the wall at the installation site.

In a three-layer wall, insulated from the outside, a window or door frame installed in the same plane with a layer of insulation at the border of the heat-insulating layer- as it shown on the picture.

This arrangement of the window, door along the wall thickness will ensure minimal heat loss at the junction.

Watch the video tutorial on the topic: how to properly lay a three-layer wall of a house with brick cladding.

When facing walls with bricks, it is important to ensure the durability of the insulation layer. The longest service life will be provided by thermal insulation with slabs of low density aerated concrete or foam glass.

It is also important to reduce the amount of moisture in the outer walls in winter period... The less moisture condenses in the insulation and cladding, the longer their service life and the higher their heat-shielding properties. To do this, it is necessary to take measures to reduce the vapor permeability of the bearing wall, and for a vapor-permeable insulation, it is recommended to arrange a ventilated gap at the border with the cladding.

For insulating a three-layer wall mineral wool it is better to use slabs with a density of at least 75 kg / m 3 with ventilated gap.

A wall insulated with mineral wool with a ventilated gap dries faster from construction moisture and does not accumulate moisture during operation. The insulation does not burn.