What kind of insulation for the concrete floor. How to insulate a concrete floor: a description of all possible methods. Methods for insulating a concrete base and their features

In the old days, it was considered normal practice to lay clean flooring directly on the concrete base of a private or panel house, as a result of which the floors were cold. This is very uncomfortable for people living there because of the unpleasant sensation of cold in the legs. In numerical terms, the heat loss through such a coating is 20% of the total heat loss of the building. That is why it is important to insulate the concrete floor, and we will tell you how to do it right with your own hands in this article.

The better to insulate the floor

The range of materials that can be used to insulate concrete floors in a private house is so wide that it is sometimes very difficult for an ignorant person to choose a suitable insulation.

To determine what can be used to insulate a concrete floor and which of the materials is the best, you should find out the following points:

where is it planned to perform thermal insulation - in a house, apartment or in the country?
how is the insulated concrete base located in relation to other structures: above the basement of a panel house, on the ground on the first floor of a private cottage, or is it an apartment floor?
is the purpose of the event - to make simple insulation or to install a warm water floor (as an option - electric)?
what is the chosen method of thermal insulation?
the amount of the budget allocated for the event.

Generally speaking, the insulation for the concrete floor can be taken from any of the existing ones. The main thing is that it fits the listed conditions. There is only one limitation: you cannot use materials containing glass wool inside residential premises. This is the answer to a frequently asked question - is it possible to insulate the floor with foam.

What does clarification of the first point give us? If we are talking about an apartment in a brick or panel house, then we can be limited by the height of the ceilings, and therefore it is necessary to choose the most effective and thin insulation - penoplex or extruded polystyrene foam. Otherwise, the floors will rise by at least 150 mm, this must be taken into account, including when insulating floors on the loggia. Moreover, penofol or isolon will not work, it has insufficient thermal resistance.

For reference. To imagine what thickness of different materials will be required for floor insulation, it is proposed to study the diagram with the thermal conductivity coefficients. The lower the value of the coefficient, the better the properties of the insulator, and the layer will be thinner.

You can inexpensively insulate the concrete floor in the country by using expanded clay for this purpose, you just need to choose the right layer thickness. It should be noted that expanded clay passes 3-5 times more heat than foam. If the dacha is constantly heated and the requirements for thermal insulation are high, then on the ground it is necessary to provide a layer thickness of at least 300 mm. With periodic heating of the cottage, it is enough to make the thickness of expanded clay insulation 100-150 mm so that the event will cost you quite cheaply.

The greatest heat loss through floors is observed when the concrete screed is set on the ground. Then there are 2 options: use the best and most effective insulation like penoplex or something cheaper, but with a thicker layer. As a rule, in these cases all types of foamed polymers are used, as well as high-density mineral wool. You can take roll materials, but you can put them in the insulation in only one way - on the logs.

It makes sense to insulate interfloor floors in a panel house only in one case - when installing electric or water heated floors. If this is not done, then your warm floor will heat the neighbor's ceiling from below, and there will not be enough heat for your own home. Since the temperature difference on both sides of the floor will be small, foam up to 50 mm thick or polystyrene foam 25-30 mm will fit for insulation. A layer of mineral wool will have to be done more or lay it together with foil-clad foam foam, which will simultaneously serve as waterproofing.

Council. The overlap on the first floor of an apartment or private house should always be insulated if the basement is not heated.

Thermal insulation methods

At the moment, there are only 2 methods of warming concrete floors in any residential buildings, the choice of a suitable material largely depends on them:

the so-called dry method - insulation on logs;
"Wet" method - laying of insulation under the cement-sand screed.

Note. There is a practice of thermal insulation of rooms on the ground floor from below, from the basement side. It is convenient and cheap, but not very effective, as it should be combined with insulation of the foundation and basement of the building. When there is none, the cold will penetrate from the street through the edge zones of the concrete base.

The insulation technique on the logs is quite accessible and, with the proper approach, is calmly done with your own hands. It involves the use of both roll and slab insulation for a concrete floor and is designed for the subsequent laying of a finishing coating of linoleum or laminate over a flooring of boards or OSB (chipboard) boards. The list of used heaters is very wide:

mineral or ecowool in rolls and slabs: has a high fire resistance, but easily absorbs moisture and at the same time ceases to be an insulator;
foamed polymers in plates (polystyrene, extruded polystyrene foam, polystyrene foam), on the contrary, are not afraid of water, but are subject to combustion and thermal insulation characteristics are better than that of cotton wool
foamed polyethylene (penofol, izolon): the material repels moisture well and has zero vapor permeability, but is flammable. Works great with other heaters;
sprayed polyurethane foam: the best insulation of all, but also the most expensive, withstands moisture, flame (for a certain period of time) and has the highest rates of thermal insulation;

For reference. There is also cork insulation on sale, but it is usually not chosen for insulation of concrete floors, it is intended for heat and sound insulation of walls.

The essence of the second method of warming is to embed a heat-insulating layer under a cement-sand screed, and almost any floor covering is laid on top of it. This means that floors insulated in this way are made not only for laminate or linoleum, but also suitable for laying tiles. This is true in the kitchen or bathroom, where there is high humidity, where the screed will last much longer.

When installing electric or water-heated floors, this insulation method is also the most effective. Of course, it is possible to lay the pipes of the heating circuits between the logs, but this will not achieve a large heat transfer area. And the screed monolith becomes, as it were, a solid heating device, heating the room with its entire surface. Therefore, usually warm floors are made of the same type (under the screed) throughout the house, and not only in the bathroom or kitchen.

It is logical to assume that it is impossible to use soft or rolled materials for the second method of insulating concrete floors. Foamed polymers or basalt wool in slabs are suitable here, and the density of the latter should be at least 115 kg / m3, and the thickness should be 100 mm. Polystyrene foam can be taken thinner - 50 mm, foam - 80 mm with a density of 35 kg / m3.

Floor insulation with expanded polystyrene

If you have chosen the first method, then wooden blocks - logs should be laid on the leveled and cleaned concrete screed, maintaining an interval between them equal to the width of the selected insulation. The lags are fastened with anchors or self-tapping screws on steel corners, their leveling is done using wood gaskets. The calculation of the height of the upper plane of the bar above the floor looks like this: the thickness of the insulation + the clearance of 50 mm for ventilation.

Council. When insulation of concrete floors is carried out with mineral or basalt materials, it is better to make the distance between the lags less than the width of the insulation by 1 cm so that the insulation fits there as tightly as possible. For expanded polystyrene plates, the interval must be made less by a couple of millimeters for the same purpose.

Now about how to properly lay the insulation. First, waterproofing is laid from a dense polyethylene film with an overlap between the canvases of 100 mm and gluing the joints with adhesive tape. Then the insulation plates are laid. From above, they are again covered with a film for vapor barrier, so that moisture from the premises does not penetrate into the insulation.

Council. Contrary to popular belief, expanded polystyrene absorbs moisture, albeit in very small proportions. Therefore, protective films on both sides of the insulation are always needed when using any materials, especially cotton wool and foam. This will significantly extend their service life.

Penofol is often used instead of film, it allows you to reduce the layer of the main insulator and protect it from moisture. The joints are also glued, only with foil tape. At this, the insulation of the concrete floor ends, you can lay the coating and laminate or linoleum.

Under the cement screed, the floors are also insulated using waterproofing laid on a concrete base. If the process starts from the soil itself, then it must be compacted, and then a concrete preparation with a thickness of 5 cm is made. After it has completely solidified, the film of the waterproofing layer is laid out, and then the expanded polystyrene plates. Usually, the cement screed is poured directly over the insulation, but we recommend laying a second layer of film first. It is inexpensive, but it will help to preserve the floor insulation material longer.

For reference. The thickness of the cement screed must be between 50 and 80 mm. The best option, taking into account different loads on the floors of the dwelling, is 70 mm.

When it comes to a wooden house, it should be borne in mind that such structures can slightly deform, because the wood "breathes". This is almost invisible in an old house, but in a newly built concrete floor coverings can crack if damping is not provided. To do this, a thin layer of polystyrene (up to 15 mm) is laid along the entire perimeter along the walls even before the start of work, as shown in the photo:

Similar measures should be taken before the installation of warm floors, a special damper tape is laid around the perimeter of the premises, and only then waterproofing is laid, which is reflected in the diagram:

Owners of old houses are often interested in whether it is possible to carry out floor insulation without opening it. There is no definite answer, since everything depends on the condition of the concrete pavement. If the screed has retained its strength, does not crumble or crack, then the option of laying insulation on top of it is possible. Only then will you have to raise the thresholds of all doors and cut their sashes, which will immediately affect the interior. So the best solution would still be to open the old floors, insulate and fill in a new coating.

Insulation of the floor with expanded clay

This insulation can be used for thermal insulation of floors in any way, even cover it between the logs, or even put it under the screed. It simply replaces foam or cotton wool, and the whole technology remains unchanged. It will cost less, but there is a question about the effectiveness of such insulation. In simple words, the best expanded clay in terms of thermal insulation properties is three times worse than the worst foam.

Hence the conclusion: the expanded clay layer should be at least three times larger, otherwise there is little sense from such insulation, the concrete floors will remain cold. It turns out that it is necessary to fill in 300 mm of material, but in which rooms is this possible? In the apartment and on the loggia - definitely not, over the ceilings will not work either. Floors remain on the ground in buildings with a high base or on logs resting on brick posts.

But in the first case, most often there is a basement and there is nowhere to place such a thick layer of insulation, and there is no need, it is necessary to insulate the foundation there. There remain floors with logs on brick pillars, such are found in old houses and on verandas. By the way, such an open veranda can be glazed, and the floors can be insulated with expanded clay from below, there will be enough space for it.

Conclusion

Each of the methods for insulating concrete floors has its own advantages and disadvantages. It is impossible to say that one of them is better and the other worse. They just need to be applied in accordance with the circumstances and in accordance with financial capabilities. Of course, a wooden floor is always better than a screed, but it requires repair and does not last so long. But in any case, good thermal insulation will not cost you cheap, this must be understood.

For a comfortable and warm stay in a house, it is necessary to come close to the issue of its insulation. Moreover, this applies not only to the walls, but also to the floor. Today, the assortment includes a wide selection of products that are suitable for floor insulation under a concrete screed. You need to choose a suitable insulation based on the type of surface (this is concrete) and operating conditions.

Review of materials

To insulate the floor under a concrete screed, you can choose the most ideal option, because the range of products is wide variety. It is most convenient to use.

Mineral wool

This heat insulator is distinguished by its environmental friendliness, resistance to moisture. Mineral wool has a fibrous structure, so that it will not let heat and noise through itself. But the material has a drawback, which is the absorption of moisture, as a result of which the cotton wool begins to rot.

In the photo, mineral wool

But even at high mineral wool, it is not very strong and tough, so it will not be able to withstand high pressure. Insulation is used for thermal insulation of a concrete floor along logs or as an auxiliary layer for hydro and vapor barrier. But what are the properties and characteristics of mineral wool, is described in detail in this

Glass wool

In the manufacture of this material, quartz sand, calcium borate and soda are used. Glass wool has long been actively used in the construction industry. She went to all environmental requirements, does not lend itself to combustion, does not emit harmful components. In addition, glass wool is also an excellent insulation, through which sounds and heat do not pass.

In the photo - glass wool for concrete floor

Its only drawback is its low mechanical strength. Glass wool is excellent for concrete floor insulation. And she is also an irreplaceable assistant in thermal insulation of vertical surfaces. But what are, the information from the article will help to understand.

Gypsum fiber

On sale, the material is presented in the form of plates, which differ in size. They are equipped with folds, which simplifies the bonding process. The installation process of the material is simple.

In the photo - gypsum fiber for concrete floor

After the sub floor has been laid, you need to wait until it is thoroughly dry, and only then proceed to finishing. The only negative material is the high price.

Styrofoam and extruded polystyrene foam

These two heat insulators provide excellent protection against cold, moisture and steam at home. They are characterized by high rigidity, so that they do not lend themselves to deformation. The disadvantages include the fragility of the release of harmful substances into the ambient air.

In the photo - extruded polystyrene foam

Expanded clay

This insulation is obtained by the effect of high temperatures on special types of clay. It is poured onto the required surface, and then a semi-dry or wet floor screed is performed. Expanded clay is a heat insulator, which is characterized by environmental friendliness, low heat conductivity and vapor permeability. But what are the characteristics of expanded clay concrete wall panels, detailed in this

On the photo - expanded clay for insulation of a concrete floor:

Its disadvantages include fragility and moisture absorption, so before installing it, it is necessary to lay a layer of waterproofing. In addition, expanded clay is a heavy material, as a result of which an additional load is created on the foundation and floor of the house.

Sprayed heaters

This group of materials includes ecowool, penoizol. They have a foam structure, and are applied to a concrete surface using special equipment.

On the photo - sprayed heaters

The advantages of such heaters are that they are quickly and easily laid, a monolithic surface is obtained. But the noise-absorbing and heat-preserving abilities are many times higher than other popular heaters. But how it is used is described in great detail in this article.

Which one is better to choose

Today, when insulating a floor under a concrete screed, penoplex is most often used. This insulation has high strength, as well as a number of characteristics that make it so popular:

does not absorb water, does not let steam through;
resists mechanical damage;
ease of installation and handling;
does not react to the influence of chemical components;
does not emit harmful components into the atmosphere, it is completely safe for human life.

The installation process with penoplex is quick and easy. It is necessary to spread the sheets of insulation on the floor surface, and then fix them with glue. At the same time, make sure that there is no gap between the material plates. All installation must be carried out in a butt joint.

When the styling has been completed, then mono apply another layer of insulation. Using penoplex, it becomes possible to abandon the implementation of waterproofing, because the material has clear indicators of this parameter. After that you can proceed to the finishing.

On the video, which insulation is better for the floor under the screed:

It is possible to carry out floor insulation under a concrete screed using roll materials. Read more about and gender in our article.

The most common and available are the following types:

cork mats;
isolone or penofol.

Thermal insulation of a concrete floor is based on the use of cork mats and underlays. These materials serve as a kind of addition to the existing insulation. But they cannot act as an independent heat insulator. Cork mats are produced with a thickness of 3-10 mm, thanks to which installation can be performed under any coating - laminate, parquet.

Manufacturers and prices

It is not difficult to insulate a concrete floor today, since the range of thermal insulation materials is very large. But you can only trust the following manufacturers in terms of choosing a quality one:

Ekomix (extruded polystyrene foam) - the price is 1300 rubles per package.
Isolon (foil insulation) - the price is 1200 rubles per roll.
Paroc (mineral wool) - the price is 800-850 rubles.
Rockwool (mineral wool) - the price is 1000 rubles.
Neman (glass wool) - the price is 1200 rubles.

Warming is one of the important processes in the field of construction, with the help of which you can make any home warm and cozy. When choosing a material for thermal insulation of a concrete floor, it is necessary to pay attention to the composition of the material, indicators of its thermal conductivity, moisture permeability and service life.

Concrete floors are associated with solidity, durability and reliability. But they also have a drawback - they are cold. The high thermal conductivity of reinforced concrete removes heat from residential and domestic premises. Therefore, concrete floors require high-quality thermal insulation. For this, different materials are used - fibrous, foamed plastics, bulk, etc. Having general construction skills, the homeowner can cope with the insulation on his own.

Why insulate the floor

Among the total heat losses, the floor takes a noticeable place - up to 15%. A cold floor not only "steals" kilocalories of heat - it significantly reduces the comfort for those living in the house. If the feet are cold, the general feeling of cold increases. The cold floor is especially dangerous for young children, who often play sitting and lying down, and the elderly.

The cold coming from the floor is harmful to pets and houseplants. Large heat losses also have a number of unpleasant consequences: moisture can condense on cold surfaces, and the relative humidity will rise. This will lead to the appearance of mold and mildew, which are extremely harmful to human health. Therefore, in addition to thermal insulation, it will be necessary to take care of the vapor-waterproofing of the floor.

Determination of heat leakage paths

Heat leaves the rooms in two ways - by heat transfer through concrete and by drafts through the joints with the walls. Accordingly, when insulating the floor, it is necessary to block both of these paths by choosing and installing suitable thermal insulation materials.

The choice of material for floor insulation.

The material for thermal insulation must have a low ability to conduct heat. It is characterized by the coefficient of thermal conductivity. The lower it is, the better the material insulates.

In addition, the material must:

be durable;
do not lose properties when moisturized;
easy to mount;
have a reasonable price.

Today the following heat insulators are most popular:

Fibrous. Basalt, glass and slag wool.
Monolithic. Foamed plastics in panels, plywood, OSB, etc.
Sprayable. Polyurethane foam and ecowool, applied by wet-glue method.
Bulk. Ecowool by dry method and traditional - expanded clay, sawdust, shavings.

How to choose the most suitable material for thermal insulation?

Mineral wool

Basalt wool is made from volcanic rocks. Its fibers are short and tough, and the density is high. Kt \u003d 0.034 ... 0.039 W / (m * K).

Advantages:

Strength. Withstands heavy loads, it is used for flat roofs and floor slabs under the screed.
Low hygroscopicity. When moistened, it does not lose its properties.

Basalt wool

Disadvantages:

Low elasticity. It is difficult to mount a surprise.
A large mass of insulation. It is necessary to calculate the bearing capacity of the floor and, possibly, its strengthening.

Supplied as 1200 * 600 mm mats.

Glass wool is made from waste glass production, its fibers are long and elastic. The density is lower than that of basalt wool, Kt \u003d 0.032 ... 0.041 W / (m * K)

Advantages:

High elasticity facilitates cutting and assembly.
Low density allows not to increase the bearing capacity of the floors.

Glass wool

The disadvantage of glass wool is its high hygroscopicity. When wet, the material loses its thermal insulation properties. Available both in mats and in rolls, more convenient when laying over a large area

Expanded polystyrene

The common name of the material is foam. It is made of expanded polystyrene, supplied in the form of sheets of different thicknesses. Kt 0.038-0.052 W / (m * K)

very lightweight;
well cut.

Cutting the styrofoam

Flimsy.
It crumbles.
The joints must be additionally sealed, for example, with polyurethane foam.

The polystyrene foamed with the use of extrusion has the best thermal conductivity Kt \u003d 0.029-0.032 W / (m * K). It is more durable, available in grooved sheets, which facilitates the installation of joints. Absolutely does not absorb moisture, does not need additional vapor and moisture insulation.

Extruded polystyrene is often called "penoplex", after one of the most common brands.

Foamed polyethylene

This insulation is very popular for insulation and waterproofing of concrete floors, it is laid under laminate, parquet board, linoleum. Kt \u003d 0.035-0.037 W / (m * K).

The material has undeniable advantages:

Easy.
Elastic.
Easy to fit.
Insensitive to moisture.
Provides excellent sound and vibration isolation.

Penoizol or foamed polyethylene

The disadvantage of insulation is the high price. It is produced in the form of mats (thick) and rolls, sometimes foil. Cloths are glued together with double-sided tape.

Spray polyurethane foam

Polyurethane is sprayed onto the heat-insulated surface in liquid form, foams and solidifies on it, forming a continuous layer. The texture resembles construction polyurethane foam. It has excellent thermal insulation properties - its Kt \u003d 0.023 W / (m * K).

Advantages:

Low thermal conductivity.
Lack of joints and seams.

Polyurethane foam covering on concrete floor

The following disadvantages limit the widespread use of insulation:

The high price of equipment. Very high.
High requirements for the qualifications of the operator of the spray installation.
Air temperature requirements for application.

Plywood, fiberboard, chipboard and others

Such materials are used as a heater only for thermal insulation of the second floor, above the heated rooms. Kt \u003d 0.12 ... 0.15 W / (m * K), which is three to four times higher than that of other popular materials. When chipboard is used as a heat-insulating material, it is necessary to perform especially carefully the vapor-waterproofing. When wet, the chipboard swells and can warp the finish coat.

Ecowool

The increasingly popular subfloor insulation for concrete is made from recycled or recycled cellulose fibers. Kt \u003d 0.032-0.041 W / (m * K)

The ecowool contains a bioprotector that inhibits the development of mold, fungi and microbes, and a substance that prevents combustion.

Ecowool fluffed, ready to apply

Benefits:

does not burn;
easy;
does not emit harmful substances, including in case of fire;
blown into the narrowest cracks, openings and voids of insulated structures.

The disadvantages of ecowool include:

high cost of equipment for spraying;
the need for high qualifications of the employee.

Hand dry ecowool application

For insulation of concrete floors, you can also use the manual method of applying the material - grinding it with a construction mixer in a vat and simply pouring it onto the surface to be insulated. The material consumption for the manual method is 20-30% higher, but expensive equipment is not required.

Traditional materials

Thermal insulating properties of natural materials, such as:

shavings;
sawdust;
reed mats;
peat slabs;
pressed flax and hemp fiber.

cannot compete with industrial insulation. Although they saved our ancestors from the cold for millennia.

Their advantage will be environmental friendliness and low cost.

Pressed Linen Fiber

The disadvantages are as follows:

weak thermal insulation;
hygroscopicity;
susceptibility to decay, mold and mildew;
flammability.

During the construction of a log house, a large amount of sawdust and shavings is formed on the site from the brought logs. It is reasonable to use this waste for floor insulation. It will only be necessary to take care of their impregnation with a refractory and bioprotective solution, as well as of steam and waterproofing.

Bulk materials for thermal insulation

It is also a cheap way to insulate. The most popular material of this type is expanded clay, obtained by firing a clay mixture. Its porous granules are inexpensive and provide Kt \u003d 0.1 W / (m * K).

The advantage of expanded clay is its environmental friendliness, incombustibility and ease of use. The disadvantage is the high thermal conductivity and the need for labor-intensive cement screed, which significantly increases the cost of the solution.

Expanded clay

Less commonly, other bulk materials are used - foam glass, vermiculite, foam chips or expanded polystyrene. They are better for insulating in a limited budget.

How to insulate a concrete floor

The technology of thermal insulation of floors is simple, but all the requirements of the technological process must be met strictly. An attempt to save time will lead to the ineffectiveness of all insulation. When choosing a method of insulation, the method and degree of thermal insulation of the foundation, basement and blind area should be taken into account. How to properly waterproof and insulate a concrete floor? The technology depends on the selected material.

Fibrous materials

The main thing when working with mineral wool is not to forget about the vapor barrier, joints and fit. The thickness of the layer is chosen depending on the climatic zone, in regions with a mild climate 50 mm is enough, in frosty places it is better to lay 150.

Lay the vapor barrier membrane, connect the joints of the sheets with metallized adhesive tape.
Install lags. Their height should coincide with the selected thickness of thermal insulation, step - with the dimensions of slabs or rolls of mineral wool. Plates or rolls should fit between the guides without play.
Lay the insulation. Particular attention to joints and abutments to walls.
Spread the vapor barrier membrane over the boards with the smooth side up. The membrane will wick away moisture.

Laying basalt wool over a waterproofing membrane

Lay dowel or thick plywood. Fasten to the logs with self-tapping screws.
Next, you can lay the final finish: laminate, parquet, cork or linoleum.

Expanded polystyrene

Expanded polystyrene is often used under a cement screed. The material is not hygroscopic, it can be used in humid rooms - kitchens, bathrooms, bathrooms, saunas.

Prepare the concrete surface. Fill up cracks, crevices and potholes, level the protrusions.
Clean from oil and oil stains and other contaminants.

Important! Alignment is required more thoroughly than in the previous case. It is necessary either to concrete the floor to be insulated with a leveling mortar, or to cover the surface with fine sand and carefully level it.

Thermal insulation with extruded polystyrene foam under the screed

Lay the insulation boards back to back over the entire floor area.
The tongue-and-groove plates are laid using projections. The joints of the foam plates are sealed with polyurethane foam.
Along the entire wall line, lay and glue a damper tape, which allows the screed to expand and not break during temperature fluctuations. The tape can also be nailed to wall blocks in aerated concrete houses.
Roll out polyethylene not thinner than 0.5 microns over a layer of insulation, with an overlap of 10-20 cm, glue the canvas with double-sided tape. This layer will prevent moisture from leaking from the cement screed.
Place the armature. If there is a water-heated floor in the room, mount pipes, fittings, etc. on top of the reinforcement system.

Installation of underfloor heating and fittings

Pour the screed.

Sprayed materials

This method will require purchasing or renting expensive equipment. Most owners only lease their units with qualified operators. Manufacturers also produce disposable non-rechargeable kits for self-use.

Prepare the concrete surface. Fill cracks, cracks and potholes, level large protrusions.
Clean from oil and oil stains and other contaminants.
Careful alignment need not be done.
Mount the lag system on which the floor will rest. Secure with self-tapping screws with dowels or nails from a construction gun.
Moisten the concrete so that the foam sticks better.

Spraying polyurethane foam between the lags

Spray concrete floor insulation. The foam volume increases by 5-10% during solidification. This must be taken into account.
Wait for the foam to dry completely.
If the floor will not be laid immediately, cover the foam layer with light-shielding material.

Other methods of floor insulation are also used, such as backfilling with expanded clay, followed by a cement screed. This method also does not require careful floor leveling. If you add a sufficient amount of special polymer additives to the cement mortar, then the screed itself will acquire thermal insulating properties.

Before you start

For work on thermal insulation in most cases (except for sprayed coatings), only the usual set of construction tools is required, first of all:

circular saw or jigsaw;
screwdriver;
roulette;
corner;
level;
construction knife.

Almost all work on floor insulation can be done alone. But with an assistant, the time will be significantly reduced, especially if a screed is made.

Insulation for concrete floors is necessary not only for private houses, but, quite often, for a city apartment, especially if it is located on the ground floor above a cold basement. Therefore, the demand for these materials is increasing every year, especially since the thermal insulation of the floor in a high-rise building often serves not only to preserve heat, but also acts as a sound insulator.

Due to the increasing demand for these materials, manufacturers are constantly developing new options and improving those that were previously manufactured by companies. To determine the choice of insulation that is suitable for a particular structure both in terms of its operational parameters and cost, one should take a closer look at the characteristics of the materials on sale.

Types of materials suitable for insulation of concrete floors

If we recall the still relatively recent past, then the most affordable insulation used for various structures was glass wool, and by no means of the best quality, so few decided to use it for insulating living quarters, and few people seriously engaged in thermal insulation of floors in apartments. Today, even glass-based wool is of excellent quality, but apart from it, manufacturers offer a very wide range of thermal insulation materials suitable for concrete floors. Among modern heaters, you can find synthetic, that is, artificially created, natural and mixed materials. Accordingly, those that are made only from natural ingredients have a higher price.

Synthetic insulation materials include the following materials:, expanded polystyrene (unpressed, that is, ordinary white foam, or better extruded), polyethylene foam (ordinary sheet or with a reflective foil coating), as well as expanded polystyrene concrete.

Mixed insulation products, which include both natural and artificially produced substances, include: glass wool, stone wool, gypsum fiber insulation and wood fiber mats.
The list of natural thermal insulation materials includes expanded clay, vermiculite, ecowool (cellulose insulation), linen plates, cork products, foam glass, sawdust and shavings.

Synthetic insulation

Polyurethane foam

Polyurethane foam belongs to the group of gas-filled plastics, which are 87 ÷ 90% composed of inert gas, due to which this material has low thermal conductivity, being an excellent insulation. The thermal conductivity coefficient lies in a record low range - from 0.024 W / (m × ° K) (theoretically) to 0.035 (in real operating conditions).

Expanded polystyrene

Expanded polystyrene as a heater can be divided into two subspecies - this is the familiar white foam and extruded polystyrene foam. Both one type and the other are produced on the same basis, but using different technologies.

Polyfoam is produced using the technology of foaming raw materials made from petroleum products. The manufacturing process consists of six stages - foaming the raw material, drying it, stabilizing it, baking (combining individual granules into plates), ripening the finished product and cutting the resulting material into plates of the desired size.

The extruded version of expanded polystyrene is produced by the extrusion method. The manufacturing process also consists of several stages. First, the raw material is combined with carbon dioxide and freon, heated to certain temperatures under high pressure, and the finished mass is passed through an extruder. The result of these operations is high density slabs with a structure consisting of small, evenly distributed, closed cells.

The size of expanded polystyrene boards from different manufacturers may vary, and their thickness is usually kept within a certain range of standard values \u200b\u200b- these are 150, 120,100,80,60, 50, 40, 30 and 20 mm.

Ordinary polystyrene does not have docking locks, so it is mounted end-to-end, and due to the lack of plasticity, there is no escape from the docking seams, which have to be worked on additionally. Extruded polystyrene foam is often produced with or without spike-groove locks, that is, with flat ends. Locking slabs are used to insulate the floor under a concrete screed to create a seamless coating, and without locks they are used for floors on logs - insulation is laid between them.

To clearly see what is the difference between these materials from each other, you can study the comparative table of their technical parameters:

Parameter name	Extruded polystyrene foam	Styrofoam
	0.028 ÷ 0.035	0.036 ÷ 0.050
	0,018	0,025
Density kg / m³	28 ÷ 45	15 ÷ 45
Water absorption,% by volume in 24 hours, no more	0,2	1,0
Water absorption,% by volume for 30 days	0,4	4,0
Compressive strength at 10% linear deformation, MPa	0.25 ÷ 0.5	0.05 ÷ 0.2
Static bending strength, MPa	0.4 ÷ 1.0	0.07 ÷ 0.2
Operating temperature range, ˚С	-55 to + 75	-50 to + 70

The advantages of extruded polystyrene foam and conventional foam include the following qualities:

Low thermal conductivity allows you to effectively insulate the surfaces of rooms, facades, attic floors, and under-roof space.
Both types of expanded polystyrene have a very low weight, so they can be used to insulate the floor in an apartment of a panel house, since the material will not weigh down the floor slab.

The cellular structure of materials allows not only to insulate, but also to a certain extent to soundproof surfaces. For this quality, foam plastic is in the lead, since it has a lower density compared to extruded insulation. But to be honest, the sound insulation performance, especially against low frequency or impact noise, is not particularly outstanding.
Extruded polystyrene foam is a versatile material, as it is used for external and internal insulation in almost any part of the building.
Not susceptible to biological effects. Mold fungus and other microorganisms-pests do not take root on this insulation.
Easy installation of plates on any flat surface. Both one and the second version of the insulation can be used to insulate the floor along the logs, as well as under the screed. However, the material is not plastic and when gaps are formed between the lags and the insulation, they must be filled with polyurethane foam in order to avoid the formation of cold bridges.
The affordable price of regular foam has made it more popular than extruded insulation.

Foam has more disadvantages than extruded polystyrene foam, but both materials have them.

Destruction of the structure of the insulation under the influence of ultraviolet radiation. Therefore, if the facade part of the walls is insulated with it, then you cannot leave it open for a long time.
Insulation materials are incompatible with paints and solutions based on turpentine, acetone and some other substances from this series.
Insulation toxicity. Over time, expanded polystyrene oxidizes, and during this process various toxic substances that are dangerous to humans are released into the environment - formaldehyde, toluene, acetophenone, methyl alcohol and ethylbenzene. Oxidation begins to occur under the influence of heating the plates to a temperature of 30 degrees. Extruded material oxidizes more slowly than regular foam. It should be noted here that the new, just laid material also releases styrene, since polymerization does not end during the production of the insulation, and the release of harmful substances will continue until this process is completely completed (such is a kind of chemical inertia).

Flammability of expanded polystyrene. According to GOST 30244-94, this insulation belongs to the flammability groups G3 and G4, which include the most flammable materials. Moreover, when burning, these materials emit a whole "bunch" of toxic compounds that are dangerous not only for health, but also for human life, since they contain hydrocyanic acid, phosgene, hydrogen bromide, etc. In addition, when burning, polystyrene foam melts and turns into a liquid state, it is able to spread onto nearby surfaces, spreading fire to them.

If, despite these negative qualities, it is nevertheless decided to purchase this particular material, since it is suitable for the price and insulation characteristics, then you should know what parameters you need to pay attention to when choosing it.

The letter "C" in the foam labeling means that the material contains flame retardants that reduce its flammability. However, it must be borne in mind that such expanded polystyrene ignites much harder, but if the combustion begins, then it burns no worse than a heater without fire retardants.

it is worth choosing PSB-S-35 expanded polystyrene, it is best suited for laying under a screed.
It is also necessary to pay attention to the manufacturer of the products, and if he is unknown, then you should not expect any guarantees of safety, neither in the composition of the material, nor in its flammability. The best on the Russian market are heaters from the European companies Nova Chemicals, BASF, Polimeri Europa and Styrochem, as well as domestic producers - Technonikol, Penoplex, Thermoplex and Europlex Primaplex.

Polyethylene foam

When it comes to foamed polyethylene, the most popular material from this category usually comes to mind - "penofol". Similar heaters can be produced under other brands, with almost identical characteristics, but to consider their features, we will take penofol as an example.

This is a fairly inexpensive and fairly practical insulation material made from non-cross-linked polyethylene foam. An aluminum layer is applied to one or both sides of the insulation, which is designed to reflect the heat flow in the desired direction. In addition, the layer is also a reliable vapor barrier.

In addition to aluminum foil, some manufacturers use lavsan for the reflective layer, a polymer-based material that has good reflectivity in the infrared range.

This material is often used to reflect heat into a room when arranging electric cable and infrared "warm floors", laying it under the heating system to be installed.

Penofol is divided into three types:

"A" - these are canvases with one-sided foil.
"B" - insulation with double-sided foil.
"C" - a material equipped with a foil layer on one side and an adhesive layer on the other (self-adhesive "Penofol").

The thickness of the base of the insulation, that is, polyethylene foam, can be from 2 to 10 mm, the aluminum layer is usually about 15 microns. However, even this thickness of the foil is enough to reflect up to 95% of the generated heat, and the layer of polyethylene foam retains heat in a traditional way for all heaters.

If we consider the characteristics of each of the types of "Penofol", they will look something like this:

Parameter name	Type "A"	Type "B"	Type "C"
Thermal conductivity coefficient, W / (m × ° K)	0,037-0,049	0,038-0,051	0,038-0,051
Thermal reflection coefficient,%	95-97	95-97	95-97
Specific gravity with a thickness of 4 mm, kg / m³	44	54	74
Water vapor permeability, mg / m × hour × Pa	0,001	0,001	0,001
Compressive strength, MPa	0,035	0,035	0,035
Dynamic modulus of elasticity under load 2kPa, MPa	0,26	0,39	0,26
Water absorption by volume,%	0,7	0,6	0,35

The range of permissible operating temperatures of this insulation for all three types is in the range from -60 to + 100 degrees.

Penofol is used in the "warm floor" system, is laid under the screed, and is also used in combination with other materials, for example, it is laid under a decorative floor covering. It is widely used for other areas of insulation, and almost zero vapor permeability makes it indispensable for thermal insulation of baths and other rooms with high levels of humidity.

Penofol prices

In addition, penofol absorbs shock and high-frequency sounds well, which means it can also act as a sound insulator.

Polystyrene concrete

Insulation of a concrete floor can also be made with such material as polystyrene concrete, which is sold in the form of ready-made slabs intended for the construction of walls, and in the form of dry mixtures for insulating floors and pouring into wall cavities during their construction. In addition, polystyrene concrete can be made independently, having all the components necessary for this.

The composition of the mixture for the production of polystyrene concrete includes the following materials:

Portland cement
Porous filler (expanded polystyrene granules)
Mineral filler (plasticizers)
Air-entraining additive (modifiers that increase the heat and sound insulation performance of concrete).
In some cases, a certain amount of sand can be added to the composition.

As you know, expanded polystyrene is practically weightless and has a low coefficient of thermal conductivity, therefore, polystyrene concrete will not have a high density, and an insulating layer of this material will not particularly weigh the floor slab.

Polystyrene concrete has the following physical and technical characteristics:

Name of material parameters	Indicators
Density, kg / m³	250-500
Thermal conductivity coefficient, W / (m × ° K)	0,075-0,145
Water absorption,% by weight	4,0
Frost resistance (number of freeze-thaw cycles)	F35-F150
Fire resistance, group	D1
Compressive strength	B2.0 - B2.5
Bending tensile strength, MPa	not less than 0.7
Water vapor permeability, mg / m × hour × Pa	0,075

The positive aspects of this thermal insulation composition include the following qualities:

Excellent load-bearing characteristics with low weight, which allows you to insulate floors in high-rise apartments with this material.
High coefficients of heat and sound insulation.
Low flammability group.
Moisture resistance.
Resistance to putrefactive processes.
Durability - service life over 100 years.
Affordable price.

Polystyrene concrete is laid in almost the same way as a conventional screed - along the beacons. If the floors are made on the ground, it is recommended to equip an embankment of medium fraction crushed stone under the screed.

If the concrete floor is insulated with this material, then a waterproofing film must be laid under the solution, which will not allow the premature departure of moisture from the solution, and the concrete will harden and gain strength in a natural way.

The average cost for this material (in the form of ready-made mixtures) for 1 m³ is 3200 ÷ 4000 rubles. But it is quite possible to make it yourself - it will turn out much cheaper. There are tested proportions of components - Portland cement PC400, expanded polystyrene granules, water and a special additive SDO (saponified wood resin). All of these components, including the additive, can be purchased at a hardware store.

The proportions of polystyrene concrete are included in the program of the calculator offered to the attention of readers. Below are some explanations for the calculations.

Floor insulation is one of the mandatory stages of home improvement. Without competently executed thermal insulation, comfortable living in the premises is out of the question. Therefore, it is very important to responsibly and competently approach both the process of choosing a material for insulation of a concrete floor, and directly to the device of thermal insulation.

At the stage of choosing a material for floor insulation, it is necessary to pay attention to some important characteristics.

Density. The weight of the insulation directly depends on it. The less dense the insulation, the more pores in its composition and the more heat will be retained inside the room.
Strength. It is better that the strength of the material is as high as possible.
Thermal conductivity. This coefficient reflects the ability of thermal insulation to transmit heat. It is better to keep this figure as low as possible.
Moisture resistance. The higher it is, the better.
Moisture permeability. This indicator should be minimal. Otherwise, the insulation will very quickly become saturated with moisture, against the background of which its thermal insulation characteristics will noticeably deteriorate.
Durability. In this moment, everything is extremely clear: the greater the durability, the longer the selected material will serve.
Environmental friendliness. Those who plan to build an environmentally friendly building using natural and completely safe materials for health should pay attention to this parameter.

Popular heaters for concrete floors

Below is a simple table in which you can review the main characteristics of existing insulation. Be sure to take them into account when choosing a material in order to choose the kind of insulation that is best suited specifically for your concrete floor.

There are several main methods for insulating concrete floors. Each of these methods can be addressed at a strictly defined stage of the floor arrangement.

So, when creating a floor "from scratch", the heat-insulating material is placed under the screed... If the floor in your house is already ready, you can turn your attention to a system called "warm floor". It makes it possible to provide high-quality heating of the surface throughout its entire area. An excellent solution is to replace crushed stone in the composition of the mixture with perlite or expanded clay similar in properties. But this option, like the first, is relevant only when arranging the floor structure from scratch.

A very popular option for thermal insulation is construction of the so-called "Raised floor". This technique is based on the device of wooden logs, the free space between which is filled with a heat insulator.

For additional insulation of the floor, you can use a special "warm" coating, for example, carpet. However, such a method should not be considered as an independent full-fledged thermal insulation.

Each method described is applied depending on the conditions of a particular situation. They are often combined with each other to achieve maximum effect.

Competent thermal insulation consists of several layers. In the context, such a design will look like a kind of cake. Regardless of what kind of thermal insulation method will be used, work must be started from certain stages.

If a concrete floor is being repaired and insulated in an already erected structure, the old screed must be completely dismantled, after which the sand and gravel cushion must be re-filled and thoroughly tamped.
Pour the resulting pillow with a layer of "skinny" concrete, which will serve as a base for heat and moisture insulation.
Wait until the concrete base gains strength and hardness, and lay a waterproofing material on it.

Waterproofing should be as reliable as possible. Even the slightest flaws can lead to serious consequences.

Try to do everything with maximum compliance with the instructions. Any mistakes can lead to moisture penetrating into the thermal insulation, and this will have an extremely negative effect on its operational properties. After some time, moisture will reach the finishing screed, which will lead to an increase in the humidity in the room. The floors will be constantly cold, and the screed itself will soon collapse. To avoid all these negative consequences, the waterproofing material must be overlapped with the obligatory gluing of all joints with adhesive tape.

After completing the laying of the waterproofing material, you can safely start laying the insulation. Plates and mats are fixed with special glue. The materials themselves should be placed in a breakdown. This approach allows you to reduce the risk of cold bridges and achieve a higher strength of the insulation layer. Along the perimeter of the insulation, as well as between the edges of the material and the surface of the wall, you need to place a damper tape.

It is important to know that a heat insulator such as polyurethane foam can be laid in the form of plates, as well as applied by spraying. The second option allows you to obtain a seamless heat-insulating layer with better quality characteristics. Polyurethane foam requires the obligatory arrangement of hydro and vapor barrier.

After the main thermal insulation material has been completely laid, another layer of moisture insulation must be fixed on top of it, a reinforcing mesh should be placed on it for greater structural strength, and then a rough screed from concrete mortar can be poured. At this stage of work, additional insulation of the concrete floor can be performed by replacing crushed stone with perlite or expanded clay.

If you decide to do this, remember that perlite and expanded clay are characterized by specific performance properties, in view of which such heaters are recommended to be used in a "semi-dry" concrete screed. It is better that the mixture contains as many different fractions as possible. This will allow to achieve the most dense filling of the solution and will contribute to a significant increase in the strength of the screed.

The screed must dry completely and gain the required strength. Only after that it will be possible to start installing the topcoat. At this stage, it is also possible to increase the thermal insulation properties of the floor. It is only necessary to lay a special warming substrate and select materials that are characterized by normal thermal conductivity. The substrate in this case is polyethylene foam or cork material.

Please note that a specific type of flooring can only be combined with a specific type of backing material.

For example, polyethylene foam cannot be combined with linoleum; in such a situation, a cork is better suited. So before buying a reinforcing pad, be sure to check with your sales consultant if it works with your chosen topcoat.

To achieve maximum thermal insulation performance and create the most comfortable living conditions, it is recommended to install an electric or water heating system.

The water system is more complex to set up. It requires not only the installation of pipes under the screed, but also the installation of special equipment designed to heat and ensure the forced circulation of water.

The heating system is installed directly on top of the heat-insulating material. It is important that the insulation is foil-coated, due to which more heat will be reflected into the room... In the absence of a foil barrier, it is recommended to lay it by hand.

The system is installed according to the manufacturer's instructions. After checking its performance, you can lay a reinforcing mesh to strengthen the structure and start arranging the screed. When using the "warm floor" system, the solution can be prepared without gravel, expanded clay and other aggregates.

This type of insulation can be used on the upper floors of a multi-storey building. In such conditions, it is necessary to monitor the thickness of the thermal insulation layer. With every centimeter of room height taken away, the conditions of being in it will be less and less comfortable.

Insulation of a concrete floor using a raised floor system. Procedure

First the floor surface is thoroughly cleaned of any dirt, and then, if necessary, it is aligned.
By room area lags are installed... For them, a 5x10 cm wooden beam is suitable. Logs should be mounted at a distance of 0.5 - 0.6 m from each other and about 0.1 - 0.15 m from the walls.
Stays on top waterproofing material... A simple plastic wrap will do. Pieces of material should be overlapped, not forgetting to glue the joints with tape.
Inside thermal insulation is arranged... Mineral wool, expanded polystyrene, perlite and almost any of the previously considered heaters are perfect.
Chipboard or moisture-resistant plywood is placed on the logs, after which about the finishing coat is being built.

Consider the fact that the height of the room can be significantly reduced due to the raised floor. Therefore, before using this method, consider its appropriateness several times.

Thus, there is nothing particularly complicated in self-insulation of concrete floors. It is only necessary to select suitable thermal insulation materials and determine the optimal installation method. Stick to the technology, remember the main rules and nuances, and the thermal insulation you create will reliably prevent heat loss. Good luck with your work!