How to insulate a concrete floor in a private house. Insulation for concrete floors: choosing insulation for concrete floors, as well as video installation instructions Insulation for heated floors with concrete screed

The concrete surface is especially cold in the winter, so it must be insulated. You cannot do without a warm surface if there are small children in the family. It is advisable to carry out insulation of a concrete floor in a private house at the construction stage, then it will save heat and improve the microclimate in the rooms. Also, an insulated coating will allow you to save on heating and additional heating devices.

Types of insulation

To insulate a concrete floor in a private house, materials with heat-insulating properties are used. Today there are three methods of insulation:

spraying polymer insulation (penoizol, polyurethane foam);
fibrous materials (glass wool, mineral wool);
foamed molded insulation (polystyrene, polystyrene foam).

These materials have the same effect, but differ in installation technology.

Fibrous

When used, soundproofing and thermal insulation of rooms is ensured. The material is resistant to combustion, but does not like moisture. When in contact with liquid, it decreases in size and increases the heat transfer process. Fibrous insulation materials are not recommended for use in rooms with high moisture where there are leaks.

Technology

Installation of a concrete surface of a house consists of the following steps:

The concrete base is prepared: irregularities and cracks are covered, stains are removed. The floors are covered with film on top, and the joints are glued with tape.
Next, logs are installed, the thickness of which is equal to the thickness of the insulating layer.
A membrane film with waterproofing properties is laid on top of insulated floors, which is capable of removing steam from the insulating layer and preventing water from leaking out.
Next, lay plywood sheets one centimeter thick and fasten the insulation with self-tapping screws. On top, linoleum or other finishing coating.

Foam molded materials

Insulation of private houses is possible with polystyrene foam or polystyrene. These insulating layers are resistant to moisture and, thanks to this property, are used in insulating a bathroom, kitchen or other room with high humidity.

Technology

When insulating a concrete floor, it is important to ensure a clean surface, so before starting work, remove dust and debris from the coating. Cover possible cracks and remove bulges on the surface. To give the concrete floor an even coating, the floor is covered with a thin layer of sand. After preparing the surface, insulation boards are installed, installing elements in special grooves. This design of the slabs facilitates the laying of the product and prevents the formation of gaps.

The slabs are laid around the perimeter of the working surface. On concrete floors, a polyethylene film is laid, which is attached on top of the insulation. The use of film prevents leakage of concrete mortar and the formation of voids and cracks. Next, install the reinforcement and begin pouring concrete. After laying the solution, the poured surface is leveled and left to dry, ensuring the necessary conditions. The finishing coating is laid on the hardened concrete screed.

Polymer insulation

Use insulated polymer material in rooms with high humidity. Polymer material is a protective layer that is resistant to rotting and fungi. The disadvantages of polymer insulation include: fire hazard and toxicity in products manufactured without complying with sanitary standards.

Technology

Work on insulating concrete floors with polymer materials is impossible without professionals. The insulating layer is applied in the form of foam, which then increases in size, which eliminates the need for seams during thermal insulation. Polymer insulation is applied using a designated device in which carbon dioxide and polymer liquid combine under pressure.

Before applying the insulating polymer layer, clean the surface from dust and debris, which can reduce adhesion to the material. Next, the logs are attached and secured with self-tapping screws. Moisten the surface, which will increase adhesion, and begin spraying the insulating composition.

Polymers are applied using special installations. The foam is sprayed between the joists, where it increases in size after application. Wait for the foam to harden, which occurs within 24 hours, and begin installing the joists and laying the finishing coating.

It is important to remember that polyurethane foam is susceptible to direct sunlight, so if necessary, leave it for several days in the open sun, cover the material with film.

Other

Due to its characteristics, polystyrene foam is widely used for insulating surfaces.

There are other insulation materials, such as:

Styrofoam. It has low cost, thermal insulation and resistance to moisture penetration. The use of this insulation is popular in the world of construction, however, when using it, do not forget that foam plastic has a fragile structure.
Mineral wool. This insulation material is capable of excellent heat retention and sound insulation in rooms. The advantages of mineral wool include its fire resistance, chemical resistance to aggressive substances and fungi, as well as vapor permeability, durability and ease of installation. Mineral wool is an environmentally friendly product that does not harm human health. Disadvantages include high moisture absorption and lack of rigidity.
Extruded polystyrene foam. It has high thermal insulation and moisture resistance. Expanded polystyrene is an improved polystyrene foam, the cost of which is higher, but also greater strength, which allows you to work with this material without any problems and with your own hands.
Foam glass. The service life of this material reaches one hundred years; it is resistant to corrosion and temperature changes. It is not susceptible to deformation under mechanical stress and is not susceptible to mold, mildew and microorganisms. Foam glass is highly durable and does not require additional fastening during installation. The material is resistant to fire and moisture and has sound insulation. The disadvantages of foam glass include: high cost, fragility, inability to pass steam and heavy weight of the blocks.
Polyurethane foam. It has high adhesion to various building materials, is manufactured at the installation site, which significantly reduces transportation costs and responds to changes in temperature conditions. The material is lightweight and monolithic, which reduces the formation of joints and seams. However, the use of polyurethane foam is impossible without protection, as it can wear out under the influence of ultraviolet radiation. The protective layer is paint, plaster or panels.
Expanded clay. It has low thermal conductivity and is used in concrete mortar instead of gravel. Due to its high porosity, it requires insulation from moisture penetration. The advantages of insulated expanded clay include: low cost, ease of installation, which allows you to install it yourself, provides high sound insulation and resistance to sudden temperature changes. The material is highly environmentally friendly, does not emit harmful toxins and is safe for human health. The disadvantages include: the fragility of expanded clay, increased accuracy of installation and the large thickness of the thermal insulation layer.

The insulation is laid under the floor screed in two cases - on floor slabs or floors on the ground. Depending on the operating conditions (basement, attic or interfloor ceiling), floor covering and the maximum permissible level of rise of the finished floor, the structure pie and the location of individual layers in it will change.

Insulation of the floor under the screed is carried out in several cases:

In addition, insulation is laid under the contours of a heated floor on any floor if a decision is made not to use a massive ceiling as a heat accumulator. Therefore, all options will be considered in detail.

There are three types of screeds, which also affects the choice of insulation. For example, expanded clay sand is used, which has both heat-insulating and sound-proofing properties. For wet ones, the same insulation and principles of hydro-, sound- and vapor barrier are used.

Floor slab

When laying factory-made slabs or pouring them in place, it is impossible to ensure a vapor barrier for this structure from moist air from below. Therefore, a vapor barrier layer is applied over the ceiling, taking into account the following nuances:

The insulation is laid under the screed taking into account the following diagram of the relative arrangement of layers:

Important! Concrete and the acoustic material underneath form a single sound insulation system. The sound wave arriving from below is partially dissipated in the acoustic material, then reflected by massive concrete.

In the basement level

In this particular case, under the floor slabs there is either a basement or a technical underground. To ensure natural ventilation in the underground, the following products are used:

the total size of all windows must be at least 1/400 of the underground area;
the recommended height of windows from the blind area is 0.5 m, so that they are not covered with snow in winter;
It is forbidden to close vents for the winter.

Screed pie on the basement floor.

These conditions are not always met, so there may be excess moisture in the underground. Therefore, thermal insulation must have minimal moisture saturation and be laid on top of the vapor barrier.

Between floors

Unlike the basement and attic levels, there is no heat loss in the interfloor ceilings. There are heating appliances on all floors. However, to save energy, insulation is still included in the design:

without this layer, part of the heat will be spent on heating the floor slab, which will reduce the efficiency of the heated floor;
thermal insulation will reflect the heat flow and completely leave it inside the room.

Therefore, instead of extruded polystyrene foam and foam glass, foamed polyethylene is sufficient here.

Important! The most effective in screeds with heated floor contours on interfloor floor slabs is reflective insulation coated with aluminum foil. The reflective layer should be on top, that is, the polyethylene foam is laid with the foil facing up.

Attic

When installing thermal insulation of the upper floor in a building with an unheated attic, the following factors must be taken into account:

a dew point appears in this design, as the attic freezes completely;
the dew point must be moved outward so that condensed moisture can be removed from the surface by natural ventilation;
To provide ventilation in an unheated attic, dormer windows are used, which must be open all year round, similar to vents in the underground.

According to the requirements of joint venture building regulations, the vapor barrier of individual layers in the floor pie should increase from the inside to the outside. When laying insulation on top of reinforced concrete floor slabs, the condition is completely preserved:

steam penetrates from the lower floor room through the slab into the thermal insulation;
then the moisture freely evaporates from it and is removed by the flow of natural ventilation to the street.

However, for normal walking on the insulation, ladders or a full-fledged boardwalk are often laid on it. In this case, the condition is no longer met and condensation forms at the boundary of the thermal insulation and the boardwalk. The insulation loses its properties, and the boards undergo rotting, and the development of fungus and pathogenic bacteria is possible.

Floor on the ground

The arrangement of the floor pie layers on the ground must correspond to the operating conditions:

capillary suction of soil moisture and moist evaporation are possible from the soil;
sound insulation is not needed here, since there are no noise sources inside the soil
if there is thermal insulation on the outer edges of the foundation and under the blind area, the soil under the floor will never freeze;
You can use any floor covering on the screeds, including tongue and groove boards on the joists;

When choosing insulation you should consider:

There are no absolutely sealed vapor barrier layers;
moisture that gets inside the insulation will not be able to evaporate from it through the concrete layer;
when wet, mineral wool and ecowool sharply lose their thermal insulation properties;
foam glass and polystyrene retain their characteristics even when immersed in water;
From these materials it is necessary to exclude foam plastic, the density of which is too low and does not provide a 100% guarantee against shrinkage of the screed.

Floor on the ground.

Thus, of the variety of insulation materials, the best option for flooring on the ground remains extruded high-density polystyrene foam XPS or EPS and foam glass.

In the absence of underfloor heating circuits, high heat losses remain. The soil under the ground floor has a stable temperature of +5 – + 8 degrees, which is significantly lower than the same parameter in a living room (+ 25 degrees). Therefore, it is necessary to properly insulate the foundation, plinth and blind area from the outside at a depth of 0.4 m to prevent freezing of the load-bearing structures in winter. Sound insulation in this case is not necessary.

With heated floor

The situation for these operating conditions is similar to interfloor slab floors. Thermal insulation is laid under the pipes of water or electric heated floors. Underneath it is a film, membrane or weld-on rolled vapor barrier material. It is better to use foam glass or extruded polystyrene foam as insulation here, since the possibility of moisture penetration remains.

Thus, when designing thermal insulation of a screed on a concrete base, different design pie designs are used, taking into account specific operating conditions.

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Owners of apartments located on the first floors of high-rise buildings, as well as private houses, are faced with a problem that brings them significant inconvenience. This is a low surface temperature of floors, which negatively affects their durability and creates discomfort for the occupants of the premises. To eliminate the problem during construction, reconstruction or repair, floor insulation is performed. The modern market offers various types of thermal insulation materials. The methods of high-quality insulation of concrete and wooden floors depend on their choice.

Attention, cold floor!

Some overly thrifty owners do not attach due importance to the problem of low floor temperature in the apartment. Wanting to save on the cost of materials and work, they arbitrarily exclude laying the insulating layer from the technological process. The consequences of such an imprudent decision are felt during the cold season:

the floor covering becomes covered with condensation;
pathogenic organisms - mold and mildew - develop in a humid environment;
the microclimate of the room is disrupted - humidity rises, temperature drops;
heating costs increase;
The service life of the floors is reduced.

To make living indoors comfortable and safe, you should adhere to the work technologies developed by the builders. Only a properly built and well-equipped house with heated floors is a real fortress. Modern materials make it possible to solve this problem quickly and without loss of quality.

7 main types of insulation materials

In order to maintain a comfortable microclimate in the house or apartment on the ground floor during the coldest winter, it is worth choosing the best material for floor insulation. It must be remembered that even ideal insulation in unsuitable conditions does not perform the required functions. To choose a thermal insulation material that meets specific requirements, before purchasing you should familiarize yourself with the main characteristics of its different types.

Basalt or mineral wool. The budget option, due to its low price, is extremely popular when building private houses and installing thermal insulation with your own hands. Attractive due to ease of installation, low thermal conductivity, and good sound-absorbing properties. High porosity promotes good vapor exchange, which is necessary to create comfortable living conditions. It does not work well at high humidity; once saturated with water, it loses its thermal insulation properties. When installing, be sure to use protective equipment. Contact of tiny glass particles on open areas of the body and mucous membranes causes prolonged itching and redness.
Styrofoam. Another inexpensive and popular insulation material, characterized by excellent thermal insulation properties and low weight. In the absence of point mechanical loads and exposure to aggressive chemicals on the surface, it is durable and reliable. It is not exposed to direct sunlight and releases harmful substances when burned. If there are rodents in the house, there is a high probability of complete destruction of the foam layer, even if protected by a screed.
Extruded polystyrene- improved foam. The developers have retained the useful properties of the old material in the new material and enriched it with additional advantages, in particular, quite high strength compared to foam plastic. Fire retardants included in polystyrene provide low flammability. The material works well even in an aggressive chemical environment, and does not pose a danger to human health. All its components are absolutely harmless.
Polyurethane foam. The extremely convenient method of applying insulation has won him enormous popularity. You just need to spray the polyurethane foam evenly over the surface from a special gun - and you can start screeding. Pros - low thermal conductivity and water permeability, long service life. The most advertised property is high adhesion to any surfaces, which is quite controversial. The material adheres really well to porous concrete, but does not adhere at all to polyethylene or galvanized metal.
Expanded clay, perlite, vermiculite. These natural materials (clay, volcanic rocks, hydromica) processed in a special way are environmentally friendly and safe. However, they are characterized by high water absorption, and in terms of thermal insulation properties they are significantly inferior to artificial insulation. To ensure the same thermal conductivity as mineral wool, a 3 times larger layer of expanded clay will be required. Accordingly, high weight increases the load on the base. Therefore, the material is more often used to insulate a concrete floor, which is installed on an earthen or sandy underlying layer; you can read more about it.
Foam glass. It is ordinary glass, factory foamed and formed into blocks. Excellent insulation, environmentally friendly and harmless. Not afraid of rodents, moisture, resistant to temperature changes and acids. Does not form pathogenic microorganisms and is completely non-flammable. Disadvantages: high cost, destroyed by pinpoint impacts, melts when exposed to alkalis.
Cork. Crushed cork oak bark, pressed into slabs, is an ideal insulation material, the only drawback of which is its high price. Otherwise, the material has a lot of useful properties: low thermal conductivity, high strength, environmental friendliness, non-flammability, biological stability, low weight, good dielectric properties. Insulating a concrete floor with cork is an excellent way to do the job yourself, accessible even to an amateur.

Installation of warm concrete floors

To insulate a concrete floor during renovation or construction, you will first need to prepare a high-quality base, leveled and protected with waterproofing. The old concrete slab is repaired and all uneven areas are filled with thin concrete. The entire surface of the base is covered with waterproofing material. To prevent moisture from penetrating into the butt joints, they are taped. Insulation selected according to the operating conditions and material capabilities of the apartment owner is laid on top of the waterproofing.

If you choose to insulate a concrete floor extruded polystyrene boards, they are placed apart. Other materials are laid close to each other, the joints are taped to avoid the formation of cold bridges. A layer of waterproofing is again laid on the insulation, and the resulting cake is protected from deformation by a reinforcing mesh. The next step is the installation of a rough screed. The insulation is poured with a concrete mixture, compacted, leveled and left to gain strength for 28 days.

Laying heated floor cable mats under the screed

Another option for insulating a concrete floor is laying cable mats on a moisture-protected base. The technology for installing electric heated floors involves making a screed about 3 cm thick. It is not recommended to lay cable mats in places where heavy furniture or plumbing equipment is installed. Floor coverings are laid on the finished screed - linoleum, laminate, carpet, etc. In rooms with high humidity, ceramic tiles are laid.

Insulation of concrete screed under wooden covering

If the project provides for a wooden covering on joists fixed on a monolithic foundation, it is necessary to perform thermal and waterproofing of the screed. The method for insulating a concrete floor with joists is not very complicated and can be done with your own hands. The leveled base is divided into separate sections, the width of which is equal to the width of the insulation. Wooden blocks - logs - are used as a separator. They are fixed to the concrete surface with self-tapping screws.

Insulation of concrete floor It may be necessary both in a private house and in a city apartment, especially in an old building, where the finishing coating (parquet or parquet boards) was usually laid directly on the concrete floor slabs. That’s why you can’t walk barefoot in most apartments in winter; your heels are burned by frost... Conclusion: you need to insulate!

So this article is about insulation of the floor in the apartment(in rooms, on the balcony or loggia) and in a private house, which has concrete floors.

Methods for insulating a concrete floor

There are actually more ways to insulate a concrete floor than are presented here. But I want to focus on those that are easier to do with your own hands and without special qualifications.

Here are these methods in order of increasing complexity:

insulation with roll insulation;
insulation along the sheathing;
insulation under the screed.

Let's consider each method in more detail.

Insulation of concrete floors with roll insulation

In my opinion, this is the easiest way to insulate the floor. Roll insulation is used. This may be more expensive:

Or cheaper foamed polyethylene, the names of which are full with and without foil:

For insulation with roll insulation, the main requirement is a smooth and clean floor surface. Clean does not mean that the concrete slab needs to be washed and shampooed. It is enough to sweep it properly so that there are no stones on it that could tear the insulation.

That's all. There is no additional hydro- or vapor barrier, because foamed polyethylene does not allow water or steam to pass through.

Further steps depend on the planned final coating. Under the tile you will have to put a layer of moisture-resistant plywood or OSB-3 on top of the roll insulation. Between the sheets of these materials we must leave gaps of 5...10 mm, which can be filled with sealant. We fasten the plywood (OSB) with dowels and nails to the slab, thus simultaneously fixing the penoizol. At this point, the insulation of the concrete floor with rolled material is completed; all that remains is to lay the finishing coating.

There is no need to put additional plywood under the laminate. And do not use penoizol that is too thick, otherwise in places where there are overlaps you will get too high “steps”...

If the final covering is a floorboard, then a gap is needed between it and the rolled insulation. If you've read about insulating a roof or wooden floor, you can already guess how to get this gap. If not, don’t worry, I’ll tell you here. We fasten the counter-lattice to the floor with the same dowel-nails, which again will help the insulation to be fixed. What a counter-lattice is can be understood from the figure, although it shows the insulation of a wooden floor:

The distance between the slats of the counter-lattice is 50...60 cm. The slats are perfectly obtained from a board with a cross-section of 25x100 mm (usually sold in 3 m lengths), if you spread it lengthwise, but you can also buy slats of 25x50 mm (for some reason they are already called a picket fence in the store , although they still need some work before the picket fence).

Insulation of concrete floors over sheathing

With this type of insulation, thermal insulation is placed between the joists installed on a reinforced concrete slab through roofing felt gaskets:

The insulation (if it is cotton wool) also needs to be placed on waterproofing, which can be used as glassine.

Waterproofing must be laid with an overlap of at least 100 mm and the overlaps must be sealed with special tape or tape.

The logs are attached in increments depending on the insulation. If the insulation is polystyrene foam, then the step is equal to the width of the slabs of this material. If we insulate with mineral wool, then it is 1...2 cm less than the width of the insulation.

The height of the logs depends on the thickness of the intended insulation layer: either 50 mm, or 100 mm, or 150 mm. Here we proceed from the feasibility of more powerful insulation and from the height of the ceilings in the room. It is clear that a 50 mm high log can be easily attached to the load-bearing slab with dowel nails by drilling through holes in the logs themselves. This number will not work with a 150 mm board...

After laying the insulation, we attach a vapor barrier material to the joists on top. Well, continue according to the “knurled pattern” (see about insulating wooden floors and concrete floors with rolled materials).

Insulating the floor under the screed

This method of insulating a concrete floor is similar to “wet” insulation of external walls. Of all those considered, it is the most labor-intensive and requires the worker to have qualifications greater than just the ability to drill a hole with a hammer drill and hammer a dowel-nail into it. Here you need to be able to fill the screed evenly, along the beacons. If you haven’t done this, then it’s better to leave it to the specialists. But if you really want to try it, it’s better to practice on someone else's material:) at a less responsible facility.

You can insulate under the screed with mineral wool of sufficiently high density:

- expanded polystyrene or pour a screed based on lightweight concrete, then no other insulation is needed:

Here I will only describe floor insulation with polystyrene foam, because mineral wool and lightweight concrete are quite clear from the photo above.

We attach sheets of expanded polystyrene to the supporting plate with “fungi”.

We put reinforcing mesh on top.

Important! The reinforcing mesh is attached to the floor slab, and not to the thermal insulation!

We set up the beacons and fill in the screed of the required thickness - concrete, not cement-sand!

Have you lost the desire to take on this? Then go ahead.

Insulation of concrete floor from the basement side

Insulation of the basement floor can be done by simply attaching insulation boards (extruded polystyrene foam or polystyrene) to it from the basement side.

To do this, rigid insulation is glued to a reinforced concrete slab using mastic or, preferably, secured with plastic “fungi”. Then we plaster over the mesh.

So we looked at four - instead of the promised three - ways to insulate a concrete floor. Good luck.

insulation of concrete floor

Insulating a floor by laying insulation on a concrete floor slab, followed by pouring a cement composition is a rather complicated process. In order to carry it out with guaranteed quality of the final result, you must first decide on choosing the thermal insulation material itself. There are a considerable number of types of floor insulation for concrete under screed, and each has its own pros and cons. Let's look into them thoroughly.

What do manufacturers offer today? It is necessary to indicate that all heat insulators are divided into several groups depending on their structural composition:

roll and slab,
bulk,
sprayed

The first include mineral wool in rolls and mats, glass wool, polystyrene foam boards, foil penofol(foamed polyethylene). To the second group - expanded clay, perlite, polystyrene chips. To the third - polyurethane foam.

Let’s immediately make a reservation that although the latter is the best, it is very expensive, and the method of applying it requires special equipment.

The rest are often used for thermal insulation of concrete floors, so let's look at them.

Expanded clay

If we talk about insulation under the screed specifically for a concrete base, then This is what expanded clay was originally created for. These are granules of foamed clay, which are simply scattered on the floor, leveled in thickness (usually within 7-20 cm) and covered with a semi-liquid concrete composition.

It is not necessary to cover the material with waterproofing. Concrete penetrates into the top layer, forming expanded clay concrete, which in its thermal properties is not inferior to any insulation.

The thermal conductivity of expanded clay is 0.16 W/m K.

Foamed polyethylene

It is also called penofol. This is a thin layer of polyethylene foam, which is covered on one or both sides with aluminum foil. The latter performs two functions:

waterproofing,
reflector of thermal energy.

Thermal conductivity – 0.037-0.051 W/m K depending on the thickness.

If you lay it on a concrete floor, then it is better to use a model covered with foil on both sides.

Polyethylene foam itself does not absorb moisture very much. But after its penetration it sharply loses its qualities. Therefore, it must be protected on both sides.

Moisture from the screed mortar will begin to penetrate into all the cracks, which can negatively affect the technical condition of the penofol.

Penofol should be laid on the floor in strips, joint to joint. The connection boundaries are covered with self-adhesive foil tape.

Using Penoplex

The name Penoplex itself is a brand. And the material itself is a high-density polystyrene board. For screed floors this is the best option.

It has low thermal conductivity - 0.031 W/m K.
It has a high density - 45 kg/m³, which affects the compressive strength. And for genders this is one of the important indicators.
Does not absorb moisture.
Does not allow steam to pass through.
Chemically inert.
Absolutely environmentally friendly.
Easy to process.

Today, manufacturers produce foam boards with a tongue-and-groove connecting lock, which makes it possible to assemble seamless coating.

The process of insulation with penoplex is simple. It is necessary to lay the slabs over the entire surface of the concrete floor, connecting them together with a lock, then stretch the reinforcing synthetic mesh over the top, and only then you can pour the solution.

Mineral wool

It should be noted that of all the insulation offered under the screed, this is the most inconvenient. The thing is that mineral wool is a hygroscopic material. It quickly absorbs moisture, becoming practically unnecessary. Therefore, it must be covered on both sides: on the side of the concrete floor with a vapor barrier film, on the side of the screed with a waterproofing membrane. Therefore, the pouring process itself begins with the installation and laying of the lower protection.

Typically, the film is laid in strips with edges overlapping within 10-15 cm, which must be secured with construction tape along the joint. Be sure to lay it over the walls, taking into account the thickness of the entire insulated pie plus the screed.
Next, the thermal insulation material itself is laid out. It is better to use mats for the floor. They should be laid tightly to each other so that there are no gaps left, which can later become cold bridges.
The top film is laid, like the bottom one, in strips with overlap and installation of tape.
A reinforcing frame in the form of a metal or synthetic mesh must be applied to such a heat-insulating cake.

note, if mineral wool is laid in two layers, then the mats should be offset by half the panel. The seams between the thermal insulation elements must not coincide vertically.

The process of laying insulation under the screed

Insulating the floor under the screed with your own hands is not difficult, if you take into account the nuances of installing each heat-insulating material. For example, polystyrene boards do not need to be covered with waterproofing. And without this, mineral wool, after a while, will become just a layer that has nothing to do with the category of heat insulators.

In this regard, expanded clay is a dual material. That is, it can be used in its pure form without covering it with a waterproofing layer . But often craftsmen also use membranes, covering them with insulating flooring.

In principle, the technology itself is the same, regardless of the chosen thermal insulation material.

Correctly lay the thermal insulation taking into account the complete and dense coverage of the concrete floor.
Do not leave gaps and cracks that can become cold bridges.
Pouring the concrete solution is carried out using standard technology, taking into account the thickness.

More and more often, craftsmen are talking about the fact that any screed, even when poured over an insulated floor, it must be carried out with a reinforcing element. The costs are small, labor intensity does not increase, but the strength characteristics of the layer increase. And this increases the service life.

Estimation of the cost of screed with insulation

The only thing that will affect the cost of a poured floor screed with insulation is the price of the latter. Here are the prices for insulation materials that are used for thermal insulation of floor bases.

Mistakes when insulating under a screed

The insulation of the screed must be approached from the position of correctly laying all the layers used. As mentioned above, if waterproofing is used, then the film must be placed on the wall. If this is not done, the liquid solution will find a way to penetrate under the protective layer and into the insulation itself.

If penoplex slabs without a locking connection are used for insulation, they must be laid tightly pressed against each other. Many people recommend filling the gaps between the slabs, as well as between them and the walls, with polyurethane foam. You can't do this. Foam easily absorbs moisture, decomposing under its influence. If you have already used it, then cover the insulation completely with waterproofing film.

The reinforcing frame must be laid in the body of the screed, and not on the insulation. Therefore, the mesh is laid with a slight rise from the surface of the heat-insulating layer. This can be done using special plastic stands, which are sold today in hardware stores.

Before insulating the floors with screed, the last must be cleared of debris. Pebbles, small debris may damage the waterproofing film or the insulation itself.