Subfloor in a house made of foam blocks: types of flooring, and step-by-step installation instructions. How to insulate a house made of foam blocks - technology and important nuances of modern thermal insulation Insulation of walls made of foam concrete blocks
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Houses made of foam blocks are able to retain heat, but they still need additional insulation work. It is important that the walls are warm, which will not only reduce the possibility of freezing of the material, but also not waste money on additional electricity consumption.
Nominally, insulation work can be divided into those that will be carried out inside, as well as external work. In general, foam blocks have a good texture to retain heat, but sometimes it is still better to insulate the premises additionally.
Insulation of a house made of foam blocks from the outside
Experts advise not to neglect and still insulate houses made of foam concrete from the outside, because in this way the material will not only be protected from the effects of water, but will also not be able to freeze. Naturally, this significantly increases their service life. For this, it is very important to choose the right material.
External insulation is the most effective
External finishing ends when the insulation is lined with additional material. For foam concrete, it is better to choose lighter structures, since, for example, brick is too heavy. To prevent foam blocks from starting to crumble, you should initially create a very stable one.
Foam block insulation scheme
Mineral wool
Versatile, not too expensive, but providing good thermal insulation. It is vapor permeable, thanks to which not only the blocks, but also the room inside are well ventilated.
It is necessary to provide access to mineral wool air
Additionally, it is fire resistant and durable. But these qualities of mineral wool will only be observed if water does not penetrate inside it. Otherwise, once saturated with it, the material will significantly reduce its thermal insulation qualities.
The process of laying insulation
But mineral wool also has disadvantages:
- During installation, you should work in respirators;
- Incorrect installation will cause additional shrinkage of the material;
- Over time, if waterproofing has not been carried out, its properties will decrease.
Expanded polystyrene
Unlike the previous material, it is not exposed to water at all.
Does not require additional waterproofing
In addition, it is cheaper than cotton wool, has high frost resistance, the ability to insulate sounds, and its thermal performance indicators are an order of magnitude higher.
Cheaper than mineral wool
In this case, the foam needs additional coating, since it can collapse under direct exposure to rays.
Insulation of a house made of foam blocks from the inside
If external insulation work is necessary, internal insulation is not always necessary. If you only do this by covering the outside of the foam concrete with some material, the walls will be cold. This will promote condensation of moisture on them, which may result in the appearance of mold and dampness.
Photo: insulation of a foam block house from the inside
Therefore, insulation work is carried out either only from the outside, or these two finishing methods are combined together.
Cork
Insulation with cork, the plates of which are made of chestnut oak, can become the finishing material in the decoration of the entire room. But it requires special preparation, which is expressed primarily in smoothly plastered walls. They should not have any damage or cracks, and at the time of installation it is important that they are completely dry and clean.
Insulation of walls with cork
Can be used as a finishing touch
However, highlighting the positive aspects that this material has, one can notice that:
- The cork adheres perfectly to the adhesive solution;
- Excellent thermal insulation properties;
- Noise insulation;
- No additional finishing is required, since this material not only insulates well, but is also used for finishing.
Before installation, the material must lie unpacked in the apartment for a day, after which work can begin.
Penofol
This material, if used with foam blocks, will help retain 97% of the heat in the room! It is made of polyethylene foam covered with aluminum foil, which increases its ability to reflect heat.
Penofol - polyethylene foam material covered with aluminum foil
Installation of penofol is carried out on small beams attached to the wall. The slabs of material are laid tightly, and the gaps between them are sealed with aluminum tape. Due to its durability, lightness and excellent thermal insulation qualities, it is receiving more and more attention.
After the work is completed, you can begin installing the finishing touches.
Polyurethane foam
Using this material, internal insulation can be done not only in the walls of residential premises, but also in attics, extensions, roofs, and so on.
An example of roof insulation with polyurethane foam
The foam fills the cavities prepared in advance in the mesh, penetrates into all cracks, preventing the appearance of “cold bridges” and instantly hardens. Polyurethane foam can last up to 50 years without requiring resumption of work.
Insulation of walls made of foam blocks with polyurethane foam
It has low thermal conductivity, but its vapor permeability is also very low. Because of this, it is important to plan an additional ventilation system in the room, since air penetration through this material is impossible.
In private construction, products made from foam concrete and gas silicate are widely used. Buildings erected with their help retain heat well and hardly freeze, but for this it is necessary to comply with technological standards.
If the masonry was carried out incorrectly and the thickness of the walls is insufficient, then additional insulation of the house from foam blocks will be required to maintain a normal microclimate. Maximum thermal stability is achieved by placing the insulator in the middle of the three-layer enclosing structure.
Advantages of external insulation
The bubble structure of the material itself is a good thermal insulator, but sometimes this is not enough. If the need for thermal insulation does arise, for example, when housing is built in an extreme climatic region, the best solution would be external insulation (foam blocks are usually not insulated from the inside).
Its advantages for the property owner are:
- high-quality sound insulation;
- reduction in heating costs;
- maintaining the overall integrity of the building and protecting it from temperature changes (constant freezing and thawing can lead to the destruction of blocks in just one weather season);
- removal of the dew point outside the building, which makes it possible to increase the dryness of the walls (in normal conditions, condensation accumulates in the depths of the foam block product, creating an ideal environment for mold growth);
- preserving usable space from inside the house;
- protection of enclosing structures from freezing and cracks.
Selection of thermal insulator
Foam concrete structures are often insulated with mineral wool, polystyrene foam and expanded polystyrene. These fillers are characterized by low cost, ease of installation and a variety of configurations.
When choosing a material, it is necessary to take into account the vulnerability of foam blocks to high humidity and correctly calculate the area of the insulated space. In the case of vapor-permeable and cellulose), installation of an additional layer of waterproofing will be required.
For water-repellent substances (foam and polystyrene foam), it is necessary to install ventilation ducts to remove possible condensation from the surface of the walls.
The main advantages of mineral wool are its fire resistance, resistance to heat loss and environmental safety. It is widely used both for insulation from the inside of a building and for external insulation.
Individual particles of mineral wool repel water, but the entire fabric absorbs it well, and therefore, when installing such material on the outside, you need to lay a waterproof film. In addition, improper installation of insulation can lead to its shrinkage and the need for repeated finishing work.
The low heat transfer coefficient of polystyrene foam and its derivatives makes it one of the best insulation materials for private construction. Insulators of this type do not allow steam to pass through, do not absorb water, and do not lose shape over time.
The disadvantage of this substance is its vulnerability to ultraviolet radiation when used outside a building. Unprotected walls are destroyed under the influence of sunlight, and therefore the better the foam is plastered, the longer the building will last.
When using polystyrene foam from inside a building, it is necessary to consider the issue of fire safety, since when melted, the material can release toxic substances.
This type of foam is especially effective as insulation for foam block buildings. During the production process, granules of raw materials are not sintered among themselves, but are fused into one mass, which significantly increases the strength of the material and its protective properties.
A negative factor will be the high price of such thermal insulators. The cost of expanded polystyrene starts from a thousand rubles per square meter.
All measures for thermal protection of enclosing structures are carried out in accordance with technical standards. Studying the documentation will help you correctly calculate the thickness of the insulating layer, as well as understand which material is best suited for a given region.
To complete the work you will need:
- pre-prepared foam boards;
- construction adhesive for attaching them;
- plastic dowels;
- reinforcing mesh;
- primer material;
- plaster;
- facade paints.
Preparation
Before installation, you need to clean the surface from dirt and debris. The remains of dried mortar are knocked off the walls, and all cracks and irregularities are thoroughly primed. The priming procedure is important for the arrangement and prevents the glue from seeping into the thickness of the blocks.
Starting metal profiles are fixed on the walls outside. In the future, the first layer of insulator will be installed on them.
To effectively adhere the material to the treated surface, you will need an adhesive solution. Its mixing is carried out in a separate container using a special attachment on a drill.
Laying
Polystyrene foam intended for wall insulation is sold in the form of ready-made slabs. The coincidence of the joints impairs the tightness of the structure, and therefore the installation is carried out in a checkerboard pattern from bottom to top. To avoid drying out of the solution and waste of material, at one point in time, not the entire wall, but a separate area is covered with glue. You need to attach a sheet of thermal insulation to it and fix it.
Additional fastening is carried out using dowels cut into the edges and in the center of each slab. The fragility of foam block products makes it impossible to use metal screws, and therefore insulation is carried out using plastic fastening elements.
Excessive load experienced by the insulation often leads to its damage. Timely installation of steel mesh will strengthen the wall structure and prevent the material from expanding beyond its limits.
Proper reinforcement involves lubricating the foam with glue, fixing a fine-mesh mesh on it that is resistant to chemical influences, and applying an additional layer of adhesive solution. To avoid cracks, the mesh is laid overlapping at the joints.
Finishing
After completion of the installation work, the surface outside the building must be brought to an aesthetic and finished appearance. To do this, it is plastered and the façade paint is applied. Different types of decorative plaster increase the moisture resistance of the surface, protecting the house from mold and fungal attack.
Do you need foam blocks? The answer to this question depends on the thickness of the walls of the building and the climate zone. If there is such a need, then it is enough to insulate the facades with one of the common insulation materials, for example, polystyrene foam, and the house will become more comfortable, and the structure itself will be additionally protected from negative external influences.
Foam block walls, due to their ability to absorb and accumulate moisture, require insulation. But how to perform thermal insulation as efficiently as possible and without harm to the structure? I suggest you familiarize yourself with thermal insulation materials and the technology of their installation, which will allow you to independently make a house from foam blocks warm and durable.
Is it necessary to insulate a house made of foam blocks?
The foam block itself has low thermal conductivity - 0.2 - 0.4 W/m*ºK. This characteristic is several times lower than the thermal conductivity of sand-lime brick. Therefore, many beginners doubt the advisability of insulating a foam block house.
In fact, it is necessary to insulate foam concrete buildings for the following reasons:
- Foam concrete has high vapor permeability. If you do not insulate the walls from the outside, the dew point will be located inside them, which will affect the durability of the entire house;
- Insulation increases the energy efficiency of housing. Despite the low thermal conductivity of foam concrete, the energy efficiency of an uninsulated house cannot be compared with this indicator of insulated housing.
Therefore, the thermal insulation of a foam concrete house is not something worth saving on. The only thing is that you can do without insulation if the house is not planned to be used as a winter house. True, even a country house intended for temporary residence will still have to be finished on the outside, since exposure to moisture will ruin the walls over several seasons.
Insulation materials
The choice of insulation depends on the area of its application. As you know, you can insulate your home in two ways:
- Outside;
- From the inside.
Below we consider insulation materials that are suitable for both cases.
Materials for external thermal insulation
The main requirement for thermal insulation materials for external use is vapor permeability. If the moisture accumulated inside the walls cannot escape, the walls will become damp.
Therefore, the following materials are usually used for aerated concrete walls:
- Minvatu. It is a fibrous insulation in the form of slabs (mats), made from molten rocks. Basalt mineral insulation is most often used, as it has the highest technical characteristics.
The thermal conductivity of basalt mineral wool is 0.055 to 0.11 W/m*K;
- Ecowool (cellulose wool). It is cellulose wool with various chemical additives that increase the fire resistance and biostability of the insulation. Ecowool is applied to the surface wet using special equipment. Therefore, you won’t be able to insulate the walls yourself using it.
The thermal conductivity of this material is 0.032-0.041 W/m*K.
It must be said that, in principle, it is possible to use vapor-proof thermal insulation materials, such as polystyrene foam or penoplex. However, in this case it is necessary to carefully vapor-proof the walls from the inside.
Materials for internal thermal insulation
Internal thermal insulation can only be used as a supplement to external insulation or if it is not possible to insulate the house from the outside. For example, you can insulate a balcony or loggia in a similar way. The fact is that after insulating the home from the inside, the walls will stop heating, which will lead to a number of negative consequences.
As for the choice of thermal insulation materials, both vapor-permeable and non-vapor-permeable insulation can be used. The only thing is that if vapor-tight insulation is used, the house will lose the ability to “breathe” and turn into a kind of thermos. Therefore, it is necessary to ensure high-quality ventilation.
As for vapor-permeable insulation, you can use all the materials described above, i.e. mineral wool and ecowool.
The following insulation materials are considered vapor-tight:
- Expanded polystyrene, or polystyrene foam. It is a cheap and effective material with thermal conductivity from 0.032 to 0.04 W/m*K. Like all polymer materials, polystyrene foam can burn even despite the presence of fire retardants. During combustion, it releases toxic substances;
- Extruded polystyrene foam (penoplex). Essentially the same foam, but made using a special technology. If you compare regular polystyrene foam and penoplex, you can come to the conclusion that the latter is superior to polystyrene foam in all important parameters, such as strength, durability and thermal conductivity.
Its only drawback is its high price. Therefore, it is not always advisable to use extruded polystyrene foam for interior work. But if you need to insulate, for example, a foundation, the choice is obvious.
The thermal conductivity of the material ranges from 0.028 to 0.034 W/(m K);
- Polyurethane foam. It is applied in the form of liquid foam using special equipment. It has the lowest thermal conductivity - from 0.019 to 0.058, and is also applied in a continuous layer, which eliminates the possibility of cold bridges appearing. The disadvantages include fragility, high cost and the inability to carry out insulation yourself.
External insulation technologies
You can insulate the facade in two ways:
- Using wet facade technology;
- Ventilated facade technology.
Wet facade
If you want to insulate and decorate a block house as economically as possible, do it using wet facade technology. Its principle is to paste the walls with insulation and then plaster.
For this we need:
- Mineral wool façade;
- Adhesive for mineral wool;
- Plaster mesh (fiberglass);
- Disc dowels;
- Perforated corners
- Facade soil;
- Decorative plaster;
- Facade paint.
Related articles:
The work includes several stages:
The work is carried out as follows:
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Insulation gluing:
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Installation of dowels:
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Preparation for reinforcement:
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Reinforcement:
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Decorative finishing:
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This completes the finishing. The result is an attractive facade that reliably protects the walls from environmental influences.
Insulation under siding (ventilated facade)
The technology of insulation under siding does not require wet work, which makes it possible to carry out thermal insulation at almost any time of the year. In addition, such a finish is more durable and durable. True, costs, compared to a wet facade, will increase by 20-30 percent, or even more.
To insulate a house under siding you will need the following materials:
- Siding or other types of wall panels;
- Additional elements for siding (corners, starting strip);
- Wooden blocks 50x50 mm;
- Wind and moisture protection;
- Mineral slabs.
The order of work is as follows:
The work is carried out as follows:
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Frame installation:
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Insulation and vapor barrier:
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Siding installation:
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The house can be finished not only with siding, but also covered with brick. In this case, the insulation is located between the load-bearing and brick walls. This technology is the most expensive and complex, since a brick wall requires a foundation, and the brick itself is not cheap.
That's all the main nuances of external insulation under siding.
Internal insulation technologies
You can insulate walls from the inside, as well as from the outside, in two ways:
- Wet method;
- Under dry plaster;
Wet insulation
The principle of wet insulation is practically no different from external insulation using wet facade technology. The only thing is that after reinforcing the insulation with glue, the surface is covered not with decorative plaster, but with putty. Putty walls can be covered with any finishing material, be it wallpaper, paint, tiles or even decorative stone.
For finishing using the wet method, you can use any slab thermal insulation materials, such as mineral wool, polystyrene foam or polystyrene foam.
Insulation under dry plaster
Dry plaster is plasterboard that is mounted on a frame. Insulation using a frame method is also similar to the thermal insulation of a facade - a frame is mounted on the walls, the space of which is filled with insulation.
The only thing is that on the outside, between the drywall and the insulation, it is necessary to place a vapor barrier membrane or penofol so that the insulation does not get wet, especially for mineral wool. The fact is that its vapor permeability is much higher than that of foam concrete.
Of course, if you are going to insulate the walls with polyurethane foam, then it will not need any vapor barrier. This material is not at all afraid of moisture and itself protects the walls from steam.
As I already said, insulation with polyurethane foam involves applying foam to the walls. The latter has excellent adhesion, as a result of which it sticks well to foam concrete and then instantly hardens.
Since PP cannot be plastered, this insulation is used only for finishing using the frame method - first the frame is installed, and then foam is sprayed. After this, gypsum board or any other sheet material is attached to the frame.
It must be said that the process of applying foam is very complex. You will not be able to properly insulate PP walls, even if you rent the necessary equipment. Therefore, it is better to entrust the work to specialists.
That's all the nuances of insulating an aerated concrete house. Finally, I note that to achieve maximum effect, it is necessary to thermally insulate not only the walls, but also the floor, as well as the attic.
This procedure is carried out in the same way as when insulating any other house - the space between the rafters or floor beams is filled with heat-insulating material, and is protected from the side of the house by a vapor barrier. After all these manipulations, your home will be warm even during the most severe frosts.
Conclusion
Now you know how to properly insulate a house made of aerated concrete and you can cope with the task yourself. If you encounter any difficulties, contact me in the comments, and I will be happy to help with advice.
Preface. In this article we will look at how to independently insulate a foam block house from the outside under siding and under plaster. For many owners of foam block houses, the thermal insulation of the room comes to the fore. We will tell you about the technology of using mineral wool, polystyrene foam or penoplex when insulating a foam block facade; at the end of the article, watch the video instructions for insulating the facade of a foam block house with mineral wool.
By the term “foam block,” private developers mean blocks made of foam concrete or gas silicate. This material is used today for the construction of low-rise buildings. The foam block itself is a thermal insulation layer. Previously, we told you how to insulate a house made of gas silicate with your own hands. Today we will look at the issue of independently insulating a foam block façade from the outside.
Due to their porous structure, foam concrete blocks provide excellent adhesion to any finishing material (plaster, putty). Many owners of country houses made of foam concrete blocks often resort to insulation. Is it worth it to insulate a foam block from the outside and how to properly insulate a foam block house for the winter? Read this article about the best materials to use when carrying out work.
Is it necessary to insulate a foam block house from the outside?
Many will ask, is it advisable to insulate a house from foam block? Because foam concrete was invented for the construction of buildings without additional thermal insulation, as they have a minimally low heat transfer coefficient. In this case, the problem of condensation formation between the insulation and the foam block wall naturally disappears. However, during Russian winters, a lot of money will be spent on heating the house.
Insulation of foam block with polystyrene foam with lining
For the high heat-saving qualities of the foam block, you have to pay for the low strength of the walls. Walls made of this material are quite fragile and will not be able to withstand the heavy load of “wet” or “ventilated” facades. In addition, the foam block is afraid of moisture and freezing; polystyrene foam, extruded polystyrene foam and mineral wool are often used to insulate the outside of a foam block house.
Experts do not recommend insulating a foam block house yourself from the inside, from the side of the heated room. However, if it is simply impossible to finish the walls from the street, and in winter a lot of money is spent on heating the room, then thermal insulation of the house is simply necessary. A layer of thermal insulation can maintain a warm and pleasant microclimate in the room.
How to insulate a foam block house from the outside
What is the best material to choose for external thermal insulation of foam blocks? The ideal option for this is slab material: Isover mineral wool mats, polystyrene foam or extruded polystyrene foam. When using mineral wool, the material should be protected with waterproofing and a ventilated gap should be provided, which will remove excess moisture and possible condensation from the surface of the film.
Mineral wool is an environmentally friendly, vapor-permeable material that can shrink if installed incorrectly. Expanded polystyrene and polystyrene foam are moisture-resistant and vapor-proof materials with a low heat transfer coefficient. When laying foam plastic or penoplex slabs on the facade, the heat-insulating material should be protected with a decorative layer from mechanical damage and ultraviolet radiation.
How to insulate a foam block house from the outside
Advantages of insulating foam blocks from the outside:
1. when insulating walls from the outside, living space is saved;
2. insulation on the outside of the house will prevent the walls from freezing in winter;
3. insulation in the room, shifts the dew point to the heated room;
4. Thermal insulation on the outside of the building will significantly extend the service life of the block walls.
How to insulate a foam block with polystyrene foam from the outside
Stages of insulating a foam block house with polystyrene foam with your own hands:
2. The façade is primed to level out the absorbency of the foam block surface;
5. the plates are glued to the facade of the house in a checkerboard pattern relative to each other;
6. We fix each polystyrene foam slab with a disc-shaped dowel in the center and at the corners of the slab;
7. A reinforcing mesh is glued to the insulation to provide the necessary strength;
8. Finally, the insulation is finished with façade putty or sheathed with siding.
How to insulate a foam block with penoplex from the outside
Stages of insulating a foam block house with penoplex with your own hands:
1. the surface of the wall is cleaned of dirt and dust, sagging or excess cement mortar on the facade is removed;
2. the facade is treated with a primer, which will ensure better adhesion of the glue to the surface;
3. a starting profile is attached to the bottom of the wall, protecting the insulation from the penetration of rodents;
4. Following the manufacturer’s instructions, glue for polystyrene foam is prepared;
5. glue is applied to the slabs with a spatula, and they are laid on the facade in a checkerboard pattern;
6. Each slab is additionally fixed with a disc-shaped dowel in the center and in the corners;
7. a reinforcing mesh is glued onto the sheathed façade to impart strength to the surface;
8. A layer of facade plaster is applied over the mesh; after drying, the facade is painted.
How to insulate a foam block with mineral wool from the outside
Stages of insulating a foam block house with mineral wool with your own hands:
1. the surface is cleaned of dirt and dust, if necessary it is additionally leveled;
2. the wall is covered with a waterproofing film to protect the thermal insulation from getting wet;
3. a starting profile is fixed on the wall, on which the first row will be mounted;
4. Next, guides made of bars are attached to the façade, between which mineral wool is attached;
5. Following the manufacturer’s instructions, basalt wool is installed between the bars;
6. then the entire structure is covered with a vapor barrier or superdiffusion membrane;
7. bars are fixed on top of the vapor barrier to create a ventilation gap of 20-30 millimeters;
8. The facade is covered with siding, PVC panels are fixed to the bars with self-tapping screws.
Specialization: Capital construction work (laying a foundation, erecting walls, constructing a roof, etc.). Internal construction work (laying internal communications, rough and fine finishing). Hobbies: mobile communications, high technology, computer equipment, programming.
My neighbor in the country recently completed the construction of a strong cottage made of foam concrete. And imagine how surprised I was when he recently approached me with a question about how to insulate a house made of foam blocks from the outside. After all, as far as I know, this porous building material has a low thermal conductivity coefficient and quite effectively protects rooms from the cold.
As it turned out, some mistakes were made when designing the walls and their thickness was not enough to maintain a comfortable microclimate inside in winter. As a result, a huge amount of gas was spent heating the cottage. Having made simple calculations, my neighbor decided that it was better to insulate the house from foam blocks - inside and out - than to continue to buy tens of cubic meters of gas.
Knowing about my considerable experience in this area, he engaged me to carry out this work, since with his own hands (according to him) he can only press buttons on the keyboard.
I am always happy to help good people, especially if this service is well paid. Moreover, there was an opportunity to tell everyone how to properly insulate a house made of foam blocks from the outside and inside. And what kind of insulation should be used to do this.
But first things first.
Features of buildings made of foam blocks
I want to tell you right away that cellular blocks were originally invented for the purpose of constructing buildings and structures with single-layer walls that do not require additional installation of thermal insulation materials. Therefore, the question of whether it is necessary to insulate the house should not arise initially.
Personally, I highlight the following advantages of residential buildings made of foam blocks without insulating the walls inside and out:
- Moisture does not condense in the layer of insulating material (due to its complete absence). Consequently, mold, mildew and other harmful microorganisms do not form on the surface of the enclosing walls and inside.
- The walls have a uniform structure, which prevents them from freezing. As a result, the building envelope retains its integrity longer, which increases the service life of the building as a whole.
- The cost of laying walls from foam blocks (which includes the price of the material) is less than from brick.
I can’t help but mention the drawback. The main one is the insufficient strength of the resulting structure. To combat this phenomenon, when building a house, I reinforce the walls with metal rods, as well as at the junction of the interfloor ceiling.
This allows you to distribute the loads more evenly and maintain the integrity of the building.
The feasibility of insulating a foam block house
And yet, I want to return to the question of whether it is necessary to insulate the house from the outside or from the inside, if foam blocks already have fairly high heat-retaining functions?
Personally, my opinion is this. If engineering calculations have been carried out correctly and the thickness of the foam concrete used is sufficient for use in the area where the building is being erected, insulation for external walls is not needed.
Well, when during your stay you find out that to maintain a comfortable temperature in the premises you have to use too much energy, you will still have to insulate the facade of the house or install thermal insulation inside the premises.
I recommend combining home insulation from cellular blocks with decorative finishing. Moreover, in some cases the finishing material (for example, ceramic facing bricks) has a low thermal conductivity coefficient. But still, the answer to the question of whether insulation is needed between a brick and a foam block largely depends on the operating conditions.
But I won’t theorize much, I’ll move on to the question of the characteristics of insulation: which is better for walls outside and inside the room? I tell you everything in detail and thoroughly.
Insulation materials
As you understand, the outer and inner surfaces of walls are used in different conditions. Therefore, for insulation, not only must different materials be used (here, of course, there are options), but the instructions for laying them themselves are different.
Regardless of your choice, I want to note that foam concrete itself is not a very durable material, so in any case, I advise you to choose and buy heat insulators that, after installation, will not put a significant load on the walls and ceilings.
Well, I’ll move on to the description of contour thermal insulation materials. First, let’s decide how to insulate the foam concrete cottage from the outside.
External thermal insulation
I won't list all the possible options because it would take too much time. I will focus on the options that I had to use most often:
- Mineral wool - n Probably the most universal insulation that can be used to insulate anything. In addition to its good technical characteristics, it is also not that expensive. Well, most importantly, in my opinion, the insulation fibers (like the foam concrete itself) do not prevent air infiltration through the enclosing structures, which allows you to create a microclimate that is comfortable for living in the room.
I can also note the long service life and fire safety, which is also very important.
However, all these advantages are negated when the insulation gets wet. As soon as moisture gets inside, the thermal conductivity coefficient of the wool increases and destructive processes begin inside, which ultimately lead to damage to the heat insulator.
To prevent this from happening, it is necessary to take measures to protect the insulating layer from moisture. For this purpose, vapor and waterproofing films are usually used, which are widely available in specialized construction stores.
- Expanded polystyrene. This material is as popular as the previous one. It also allows for good insulation of walls, tolerates low temperatures well, and also has soundproofing properties.
Well, most importantly, it is not afraid of moisture. That is, when wet, its operational properties do not change in any way, which opens up great possibilities for use.
However, insulating the outside of a house made of foam blocks with polystyrene foam requires additional decorative finishing, since the material itself does not withstand external mechanical stress and is destroyed under the influence of direct sunlight. The material is often used to insulate exterior walls under siding.
Internal thermal insulation
Now to the question of thermal insulation technology with insulation inside. I’ll say right away that I am not a supporter of this method, since the enclosing walls will freeze from the outside, which is not good from the point of view of their operation.
As for materials, here I can offer the following options to choose from:
- Cork. A material with excellent heat-retaining properties, which can play the role of an excellent and effective interior decorative finish. It is made from the bark of the cork tree, so it is completely natural and safe for humans.
But its use requires preliminary interior finishing of the walls. They need to be plastered very evenly and puttied smoothly. If there are cracks or other defects on the surfaces, this can damage the cork coating, the cost of which cannot be called low.
I will briefly list the additional advantages of cork as an internal insulation:
- it is easily mounted on an adhesive solution, practically without taking up useful space near the walls of the building;
- in addition to the low thermal conductivity coefficient, the material acts as an excellent sound insulator, absorbing noise from the street;
- The top of the cork does not need to be painted or varnished; it itself has a unique appearance.
- Penofol. This insulation is made of polyethylene foam protected by aluminum foil. It gives the material additional strength and acts as a heat reflector.
Installing penofol on the internal surfaces of the walls of a house made of foam blocks allows you to save up to 97% of the thermal energy generated by heating devices.
Penofol can simply be glued to the walls without additional waterproofing, since it is not susceptible to getting wet. Sometimes I used it as additional insulation paired with mineral wool or polystyrene foam.
- Polyurethane foam. With its help, you can insulate walls made of cellular blocks inside residential and auxiliary premises. The material is a polymer foam, which in a liquid state is applied to surfaces using a sprayer, and after hardening it forms a seamless layer that protects rooms from heat loss.
The advantage of this heat insulator is that it is not afraid of moisture and, when applied, fills all cavities, cracks and unevenness of the treated surface. Its service life is at least 50 years without the need for periodic maintenance and repair.
I can name two disadvantages:
- Difficult to use. Spraying polystyrene foam requires special equipment, which not every home craftsman has.
- Vapor tightness. After hardening, the insulating polymer becomes airtight, that is, it stops air infiltration through the enclosing walls. As a result, increased humidity forms in the room, which means you will have to take care of high-quality ventilation.
To make it easier for you to choose the appropriate technology and material, below I will tell you about several ways to insulate homes made of cellular blocks.
External insulation technologies
I’ll start with it, because I think it’s more effective. I will justify my position with several points:
- With external insulation, the usable area of the interior does not decrease (which would otherwise be reduced due to the installed insulation with hydro- and vapor barrier plus decorative finishing).
- Insulation material installed outside does not prevent the walls from heating up from the inside. If the heat insulator is installed only inside, the foam concrete blocks will be subject to cyclic freezing and thawing, which will sooner or later lead to the destruction of their internal structure.
- When installing insulation inside residential premises, the dew point will mix closer to the rooms. Therefore, moisture condenses directly in the thickness of the wall. This causes the appearance, which destroys the material.
External insulation, on the contrary, shifts the dew point to the outer surface of the wall. In this case, condensed moisture does not accumulate in the blocks, but evaporates due to air circulation in the ventilation gaps.
Wet facade
This method of insulation is quite common and is used for thermal insulation of buildings made of various materials, including foam concrete. Its advantage is that it does not require the use of complex technological equipment, and after completing all stages it is easy to perform decorative finishing of the outer surfaces of the walls.
As a material, I suggest using polystyrene foam or its more durable analogue - extruded polystyrene foam.
The scheme of work itself is as follows:
- The surface of the facade is cleaned of dust, debris, build-up of mortar, and so on. It is also important to ensure that there are no greasy marks from oil or other similar substances on the walls. If the enclosing structure has large irregularities, they should first be sealed with mortar.
- After preparation is completed, the surfaces should be primed with a composition with antiseptic properties. The primer increases the adhesive properties of foam blocks, reduces absorption and, as a result, reduces the consumption of the adhesive composition.
- A galvanized metal profile is fixed at the bottom of the wall, which will serve as a support for the lower (first) row of heat-insulating material. It can be secured with self-tapping screws or screws with dowels.
- Then the insulation boards are installed. Polystyrene foam or polystyrene foam is secured with glue, which is applied to the edges and in the middle of each plate.
After spreading the glue, the part needs to be leaned against the wall and pressed for about thirty seconds. To prevent falling off, I advise using special plastic dowels with wide heads that will firmly hold the thermal insulation in place.
They are very easy to attach. You need to drill a hole in the wall directly through the insulation, then insert the dowel and tighten the screw. Due to the fact that it is in a plastic shell, the occurrence of cold bridges is completely eliminated.
- A fiberglass reinforcing mesh is attached. It is simply glued to the insulation layer and strengthens the plaster solution, which will be applied on top of the polystyrene foam.
- The insulation is plastered over the reinforcing mesh, after which you can begin finishing the facade.
However, I like another finishing method - under siding. In this case, you can install a ventilated facade. How to do this will be discussed further.
Under siding
In this case, I will tell you how to insulate a house using mineral mats. The specificity here is to protect the heat insulator from moisture.
The work occurs in the following sequence:
- First, the surface of the walls is cleared of debris, the detected defects are repaired and the most crooked areas are leveled (there should not be any, since the foam block is usually distinguished by the accuracy of its geometric parameters).
- After this, a vapor barrier membrane is installed on the walls. This is a special film that does not allow moisture to pass through, but does not retain air, which, circulating freely through the walls, prevents the accumulation of large amounts of dissolved water vapor inside the room.
- Then the vertical sheathing is installed. For this, galvanized metal profiles or wooden blocks can be used. In the latter case, I recommend treating the parts with antiseptics and hydrophobic substances, which will extend the life of the wood.
The height of the sheathing should be equal to the thickness of the material used (mineral mats), and the distance between adjacent guides should be equal to the width of the insulation minus 2-3 cm. - Then mineral mats are inserted. If you have maintained the distance correctly, they will fit between the sheathing at will, without requiring additional holding during the installation process. But to prevent them from falling out in the future, I recommend attaching them to the wall made of foam blocks with plastic dowels with wide caps.
- Having finished installing the insulation, it is necessary to protect it with a water barrier. This film will prevent mineral mats from getting wet from atmospheric moisture and will protect the material from other destructive external influences.
- Afterwards, additional elements are nailed or screwed onto the guide battens, the height of which is 3-5 cm. This is necessary so that after covering with decorative material, a ventilation gap is formed inside, removing excess moisture from under the facade.
- The last stage of work is covering the walls with siding. Since the sheathing is already installed vertically, all that remains is to fasten the necessary parts with self-tapping screws.
The two insulation methods I described are quite simple to implement, which is why I recommend them to you. Well, now let's move on to internal insulation. This is for those who are very afraid of the cold or for some reason cannot resort to external insulation.
Internal insulation technologies
In fact, any builder knows that the layers of multi-layer enclosing walls should be positioned so that their vapor barrier properties decrease in the direction from the living room to the street. That is, if you place insulating material inside the room, this rule will be violated.
As a result, a large amount of water vapor generated as a result of human activity will accumulate in the house, which negatively affects the microclimate of the home.
Therefore, if you have to resort to technologies for internal insulation of a foam concrete house, which I will discuss below, you should definitely take care of a reliable and efficient ventilation system.
Otherwise, insulation may negatively affect the operation of the building. For example, I encountered situations where, due to strong temperature changes, foam concrete quickly deteriorated, and the corners inside the rooms froze.
But I won’t go into theoretical details; I’ll move on to describing practical methods for internal insulation of a foam concrete house.
Polyurethane foam
The most effective and convenient way of internal thermal insulation is to use polyurethane foam. It will act as a waterproofing agent and will insulate the walls well. Sprayed polyurethane foam will not let air inside the walls, so moisture does not form there, destroying cellular concrete.
On the other hand, all water vapor will accumulate inside the room, so they will have to be removed using ventilation. It is better if it is forced and triggered by a humidity sensor.
Before spraying polyurethane foam, I recommend making a sheathing in advance, onto which you can then attach the finishing material. For example, drywall. Just do not use a galvanized profile for this purpose, which will become a cold bridge that impairs the effectiveness of thermal insulation.
If you do everything as I described, the dew point, that is, moisture condensation, will be located at the point of contact between the polyurethane foam and the wall or inside the insulating layer. That is, the integrity of the enclosing structures will not be affected in any way.
In general, the material described in this section is an excellent solution for insulating a house made of foam blocks. But to apply it you need special equipment. Therefore, I propose a cheaper and easier to implement method, described below.
Foam plastic or penoplex
These two materials are excellent not only for external insulation (I talked about it), but also for internal insulation. The latter differs from the first in better performance characteristics, but also in a higher price.
The insulation technology is not much different from the process that I described above (when I talked about external insulation). There are just a few features that I want to draw your closest attention to:
- If you apply glue only to the edges and middle of the foam sheet, voids may form inside where moisture will condense. Therefore, I recommend distributing the adhesive composition over the entire surface of the insulation, using a spatula with teeth for this (naturally, you need to make sure that the walls are even).
- The gaps between the foam sheets have a very negative impact on the effectiveness of thermal insulation. Therefore, they need to be sealed with construction foam.
- If possible, I generally recommend installing two layers of foam, staggering the seams of the material so that they overlap each other.
Conclusion
Now you know how to insulate a house made of foam blocks, but I advise you to immediately build a home from this material so that it does not require insulation. As, for example, described in the video in this article. Or do you have your own opinion on this issue? If so, I'd love to hear your perspective in the comments below.