How to insulate a concrete floor in a private house. How to insulate a concrete floor: choosing materials Insulation for concreting floors

23.06.2020

concrete floor insulation it may be necessary both in a private house and in a city apartment, especially old building, where the finishing coating (parquet or parquet board) was usually laid directly on the concrete floor slabs. Therefore, in most apartments you can’t slap barefoot in winter, it burns your heels with frost ... Conclusion: you need to insulate!

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

Ways to insulate a concrete floor

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

Here are the methods, in ascending order of complexity:

insulation with rolled heaters;
insulation on the crate;
insulation under the screed.

Let's consider each method in more detail.

Insulation of the concrete floor with rolled heaters

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

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

For insulation with roll insulation, the main requirement is a flat 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 pebbles on it that can tear the insulation.

That's all. No additional hydro and vapor barrier, because the foamed polyethylene does not let water or steam through.

Further steps depend on the planned finishing 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 plywood (OSB) with dowel-nails to the plate, thus fixing penoizol at the same time. On this, the insulation of the concrete floor with rolled material is completed, it remains to lay the finishing coating.

There is no need to put additional plywood under the laminate. And take penoizol not too thick, otherwise in places of overlap you will get too high "steps" ...

If the finish coating is batten, then a gap is needed between it and the roll insulation. If you have read about the insulation of a roof or a wooden floor, then you already know 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 excellently obtained from a board with a section of 25x100 mm (usually 3 m long), if you dissolve it along, but you can also buy 25x50 mm slats (already called a picket fence for some reason , although they still need some refinement before the picket fence).

Insulation of the concrete floor on the crate

With such insulation, thermal insulation is placed between the logs installed on a reinforced concrete slab through roofing felt gaskets:

Insulation (if it is cotton wool) must also be placed on waterproofing, which is suitable for glassine.

The waterproofing must be laid with an overlap of at least 100 mm and the overlaps must be sealed with a special tape or adhesive tape.

Logs are attached with a step depending on the insulation. If this is insulation with polystyrene foam, then the step is equal to the width of the plates of this material. If we insulate with mineral wool, then - 1 ... 2 cm less than the width of the insulation.

The height of the lag depends on the thickness of the intended insulation layer: either it is 50 mm, or 100 mm, or 150 mm. Here, proceed from the expediency of more powerful insulation and from the height of the ceilings in the room. It is clear that a log with a height of 50 mm can be easily attached to the carrier plate with dowel-nails, drilling through holes in the lags themselves. With a 150-mm board, such a number will not work ...

After laying the insulation, we attach a vapor barrier material to the lags from above. Well, further along the “knurled scheme” (see about the insulation of a wooden floor and a concrete floor with rolled materials).

Floor insulation under the screed

This method of concrete floor insulation is similar to "wet" insulation of external walls. Of all those considered, it is the most time-consuming and requires a qualification from the worker, more than just the ability to drill a hole with a puncher and hammer a dowel-nail into it. Here you need to be able to pour the screed evenly, along the beacons. If you have not done this, then it is better to entrust the specialists. But with a great persistent desire to try, it is better to practice on someone else's material:) on a less responsible facility.

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

- polystyrene foam or pour a screed based on lightweight concrete, then other heaters are not needed:

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

We attach sheets of polystyrene foam to the carrier plate with “fungi”.

We put a reinforcing mesh on top.

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

We expose the beacons and fill in the screed of the desired thickness - concrete, not cement-sand!

Have you lost your desire to take it on? Then go ahead.

Basement concrete floor insulation

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

To do this, a rigid insulation is glued in a reinforced concrete slab using mastic or, preferably, fixed with plastic "fungi". Then we plaster on the grid.

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

concrete floor insulation

Concrete is used not only for the construction of foundations and walls, but also for the construction of floors. A distinctive feature of concrete is the durability and strength of the material. However, the cold surface of the floor causes serious inconvenience, as it is increased. When deciding to build a warm concrete floor, you have to decide how to insulate the base. It is important to choose the right insulation for the concrete floor and figure out how heat-insulating materials are laid on the surface and waterproofing is performed.

Concrete floor base in a private house - features of a concrete slab

The floor is a critical element of the structure. Trying to increase the service life of the building, many prefer concrete. After all, concrete is superior to most building materials in terms of performance. But along with a set of advantages, the material also has weaknesses.

Concrete performs better than most building materials

Let's start with the main advantages of concrete floors, which include the following characteristics:

increased margin of safety. The concrete surface is able to perceive significant compressive loads, while maintaining the structure and integrity of the array;
long period of use. The service life is commensurate with the service life of the building, due to the durability of the base;
ecological purity. Included in concrete mix ingredients are safe for health and do not harm environment;
ability to resist the buildup of static electricity. Airborne dust is not attracted to the surface;
Fire safety. The concrete base has a high fire resistance and does not collapse under the influence of open fire;
resistance to capillary penetration of moisture. Despite the reduced hygroscopicity, floor waterproofing is a prerequisite;
impact resistance aggressive environments and chemicals. The concrete base does not collapse upon contact with acids and alkaline compounds;
maintainability. If necessary, it is easy to repair the damaged area.

Thinking about what kind of insulation for a concrete floor better fit, we will deal with the shortcomings of the concrete base. Main cons:

increased thermal conductivity. Without additional thermal insulation, significant heat losses occur;
formation of condensate. Due to the increased temperature difference between the soil and the floor of the lower floor, moisture condenses on the concrete surface.

Concrete base has increased fire resistance

Condensation causes a number of negative factors;

increase in indoor humidity;
deterioration of the internal microclimate;
the development of fungal colonies and mold;
dampness formation.

In addition, in winter, cold floors cause many inconveniences to residents:

reduce the temperature inside the room;
increase heating costs.

But, thanks to a serious set of advantages, many construct a concrete floor. How to insulate its surface in order to avoid heat loss is of interest to owners of private houses, summer cottages and novice developers. Let's try to answer this question.

We heat-insulate the concrete floor: how to insulate the surface of the concrete base

Specialized stores offer many different heat insulators that differ operational characteristics. Many prefer traditional materials and believe that for insulation it is enough to lay a layer of foam or expanded clay granules. However, the choice of heat insulators is not limited to this.

When choosing a floor insulation for concrete, also pay attention to the following materials:

mineral or basalt wool. They are a budget solution and belong to fibrous heat insulators;
sheet polystyrene. He positively proved himself in rooms with a high concentration of moisture;

The choice of heat insulators today is very large

polyurethane foam. The material is sprayed onto the concrete surface using special equipment;
sawdust. They allow at low cost to insulate the concrete base;
heat-insulating mixtures on a polymer basis. Used in the arrangement of heated floors;
thermal insulation paint. It is applied in liquid form to the surface of the concrete floor, insulating it;
foamed glass. It is offered in the form of environmentally friendly blocks with increased moisture resistance;
cork material. It is made from natural wood pressed boards.

When deciding on a heat insulator, consider the following points:

performance properties of the heater. The efficiency of thermal insulation and the service life depend on them;
building features. The specifics of the insulation of concrete floors in a private house, a multi-storey building or in a country house are different;
the location of the concrete floor in the building. Possible options- the floor above the basement, the ceiling of the lower floor or the interfloor base;
warming method. Thermal insulation materials are used or a heated floor system is installed;
location of the heat insulator. The insulation is placed between the lags or placed on the surface when performing the screed.

Let's take a closer look at the main operational properties ah used heat insulators.

The main characteristics of heaters:

density. With an increase in specific gravity, strength characteristics increase, but thermal insulation properties decrease due to a decrease in porosity;
margin of safety. The load capacity of the thermal insulation material affects the durability and allows you to maintain its original shape under the influence of loads;
thermal conductivity. The maximum efficiency of insulation is achieved when using materials with low thermal conductivity;

Reliable thermal insulation depends on the thermal insulation materials used.

moisture resistance. For thermal insulation of the concrete base, use heaters with reduced hygroscopicity;
vapor permeability. Due to the ability of the material to pass vapor, the efficiency of air exchange is increased;
exploitation resource. Durability is one of the determining factors when deciding on floor insulation;
weight. Give preference to light heat insulators that have sufficient density;
ecological purity. Try to use harmless materials for thermal insulation purposes.

Make the final decision taking into account the characteristics of the building and specific operating conditions. For example, in a country house where there are rodents, it is not advisable to use sheet foam. And if you want to reduce the distance from floor to ceiling, use granular expanded clay. It is important to make the right decision by comprehensively analyzing all the factors.

Characteristics of thermal insulation materials for concrete floor insulation

Let us dwell in more detail on the operational properties of the most common heaters:

fibrous. A characteristic representative of fibrous heat insulators - mineral wool;
sheet. Among the many sheet heaters, polystyrene foam is most often used;
crumbly. Of the various types of loose materials, granular expanded clay is popular;
sprayed. One of the representatives is a polyurethane foam mixture sprayed using special devices;
polymeric. They are represented by an extended range of self-leveling compounds.

Expanded polystyrene is most often used for concrete floor insulation.

Let's start with mineral wool, which is available in rolls or in individual mats. Insulation is made not only on a mineral basis. Along with mineral wool, cotton wool is used using dolomite, basalt or limestone raw materials. For the manufacture of glass waste and slag are also used.

The main advantages of the material:

ease of use;
Fire safety;
increased plasticity;
reduced thermal conductivity.

However, mineral wool is able to absorb moisture and needs additional waterproofing.

Extruded polystyrene foam is sold in the form of sheets. The material is a type of foam, but differs from it in the following properties:

increased strength;
long period of use;
increased reliability;
fire safety;
resistance to aggressive environments;
ecological purity.

Among the advantages of polystyrene foam sheets are also noted:

soundproofing properties;
moisture resistance;
vapor permeability;
reduced thermal conductivity;
ease of installation.

The disadvantages include the increased cost of the material.

Granular expanded clay is a very popular insulation among builders.

Expanded clay is used in the form of granules made by firing clay. The main properties of expanded clay are:

environmental friendliness;
fire resistance;
frost resistance;
durability;
reduced thermal conductivity.

Significant advantages also include the ability to absorb noise and the inability to form mold.

Polyurethane foam - sprayed insulation. Distinctive features material:

reduced coefficient of thermal conductivity;
resistance to open fire;
possibility of use in a humid environment.

In addition, there are no butt sections and cold bridges in the polyurethane foam coating. If it is necessary to additionally insulate the surface, the first layer is applied, after which it hardens, it is re-sprayed. The main disadvantage of polyurethane foam is the need to use special equipment for spraying insulation onto the surface.

Polymer heat insulators include:

working mixtures supplied in liquid form, intended for pouring underfloor heating;
special paint, after application of which the thermal insulation properties of concrete increase.

From right choice material depends on the durability of the floor

Advantages of polymeric materials:

thermal insulation characteristics;
the integrity of the formed layer;
reduced hygroscopicity;
resistance to temperature changes;
perfect flatness.

The disadvantages include increased costs for the purchase of polymeric materials.

You should carefully study and analyze the characteristics of heat insulators when planning to purchase insulation for a concrete floor. In this case, it is necessary to take into account the actual conditions of use of materials.

Methods for warming a concrete base and their features

It is not difficult to insulate a concrete floor, having studied the technology of performing work and mastering the specifics of performing heat-insulating measures for various types of heaters. Let's dwell on these points in more detail.

Fibrous insulation for concrete floor

Fibrous heat insulator is used to insulate concrete floors between floors of a building.

Laying slabs or roll material carry out according to the following algorithm:

Waterproof the concrete surface plastic wrap.
Cut and lay the insulation on the waterproofing.
Seal the joints with special adhesive tape.
Lay a foil heat insulator on the insulating layer.

When performing work, pay attention to correct location metallized film, which must be laid with foil to the room. Then, communications of the heated floor are assembled on the prepared surface or sheets of plywood are laid.

Having studied the technology of performing work, it is easy to carry out work on floor insulation yourself

Thermal insulation of concrete pavement with expanded polystyrene

The process of laying polystyrene foam sheets does not require special training. The heat-insulating material does not need waterproofing protection and is fixed with an adhesive composition directly to the concrete base.

Carry out the work, observing the sequence of operations:

Cover the concrete surface antiseptic composition deep penetration.
Prepare the adhesive according to the manufacturer's instructions.
Apply a thin layer of adhesive to the boards and smooth it over the surface with a spatula.
Lay the heat insulator on the concrete surface and press evenly.
Lay the rest of the sheets according to the specified algorithm, ensuring the offset of the joints.

After laying the insulation, seal the butt sections with silicone, lay the mesh for reinforcement and pour the concrete screed.

We use expanded clay for thermal insulation: the specifics of laying insulation

Expanded clay granules are used for thermal insulation of concrete bases in private houses. When performing work, follow the specified sequence of actions:

Waterproof the floor with polyethylene or mastic.
Pour expanded clay on the surface and level it.
Lay the mesh for reinforcement.
Prepare the screed solution in the required volume.
Fill and level the surface of the screed.

After hardening, lay the finish coat.

In private houses, expanded clay granules are used for thermal insulation of concrete bases.

How best to insulate a concrete floor with spray formulations

Thermal insulation measures for applying sprayed insulation to the concrete floor are carried out only by professionals. After all, to perform the work, special equipment is needed, which, under high pressure, supplies a layer of heat-insulating material to the surface of the concrete floor. As a result, a solid layer of insulation is formed. Distinctive features technology - no need to level the surface and seal the joints.

The procedure for applying polystyrene foam:

Clean the concrete surface and prime with a primer.
Secure the joists to the concrete floor with steel angles.
Spray a layer of expanded polystyrene.

During solidification, the material increases in volume, acquires a porous structure, penetrates deep into the cavities and closes microcracks.

How to use polymer insulation

Polymer-based insulation is applied to the floor surface in an even layer. When performing work, follow the manufacturer's recommendations indicated on the packaging.

Follow the application procedure:

Dust the concrete base.
Treat the floor with a primer coat.
Apply polymer.

After the polymer insulation has dried, lay the final coating.

Summing up

Using different kinds thermal insulation materials, it is easy to thermally insulate the concrete floor. How to insulate it more efficiently, experts will tell you. It is important to study the properties of heaters and understand the technology of work.

August 27, 2016
Specialization: Capital construction works(laying the foundation, erecting walls, constructing the roof, etc.). Internal construction works (laying of internal communications, rough and fine finishing). Hobbies: mobile communications, high tech, computer technology, programming.

Well insulated apartment private house- this is not only a guarantee of comfort and coziness, but also a way to significantly save in the future on paying for heating services for your home.

This is exactly how I reason and, of course, this is how one of my recent clients thinks, who asked me to perform floor and floor insulation in his new country cottage(the walls there were already thermally insulated using the technology of a hinged ventilated facade).

Looking ahead, I will say that there was a huge field for activity. It was necessary to insulate the floors on the basement, first and second floors (and in some rooms I installed a floor heating system at the same time), on the balcony and attic.

So I had a unique opportunity not only to earn a lot of money, but also to tell you how to do everything yourself. Moreover, you will learn how to choose a floor insulation for concrete under a screed, and how to properly lay it.

Material selection

If you are reading this material to find out how to perform floor insulation on your own, without involving specialists, then you will definitely need to know what you need to use for this. I will talk about suitable heat insulators, and then together we will decide which insulation is best to use for work.

Requirements

You probably know many different thermal insulation materials. But I want to say right away that when laying under a screed (namely, this is how I insulated the floors in the client’s house), specific external conditions will affect the heaters, which should be taken into account.

I believe that a heat-insulating material for laying in concrete should have the following features:

Increased resistance to moisture. Water is an integral component of the screed mortar, so when pouring the floor, the insulation will be exposed to water. Not to mention further exploitation. Therefore, I always buy material that does not lose performance when wet.
Low thermal conductivity. The higher the heat-preserving properties of the material, the thinner its layer will have to be laid. Accordingly, the insulating floor cake will be smaller, and the distance between the floor and will be greater, which, for example, I like more.
Since I am going to insulate the floor on which all pieces of furniture stand and on which people walk, the insulation must be ready for such loads.

Below I will analyze some of the most popular materials and inexpensive materials for insulation. And then we will decide which of them is more suitable and why.

Specifications for individual materials

So, I’ll tell you about the three options that I have to work with most often:

Mineral wool. It is made from molten basalt fibers that are glued together with resins. The material is not suitable for laying under the screed, since it must be very carefully protected from water and crate made, otherwise the floor surface will fail.

Styrofoam. More suitable option. I had to use polystyrene for floor insulation under the screed, but for me personally, its low mechanical strength serves as a limiting factor.

Extruded polystyrene foam. The best I can offer for thermal insulation of the floor under the concrete screed. The material has low thermal conductivity, tolerates water well and is strong enough to be laid under a screed (better, of course, with reinforcement).

As you understand, I chose EPPS to work in my client's house. And in the next section I will justify my choice.

My choice for work

So, before starting work on insulation, I went to the store and bought myself the right amount of extruded polystyrene boards. trademark Penoplex. This material has excellent specifications, and its price, although somewhat high, is quite affordable for an ordinary Russian, that is, me and you. One pack of foam boards (there are 8 of them) costs from 1000 to 1500 rubles, depending on the purpose.

By the way, the material of this brand is so widespread that its name has already become a household name (at least among those people with whom I communicate). Therefore, further, if I say penoplex, then you know that it can be replaced with extruded polystyrene foam plates of any manufacturer.

But I still want to focus on penoplex. Here are just a few of its main benefits:

zero water absorption coefficient;
high heat-preserving functions;
good vapor permeability;
resistance to biocorrosion;
high strength.

If you put penoplex correctly (and I'll tell you how below), then it will protect the room not only from the cold, but also from noise and moisture. And no matter how cold it is outside.

In general, whether I convinced you or not, I chose him for the job. So we will talk about this heat-insulating material further.

I also had to insulate the concrete floor with foam without screed. But in this case, you need to mount the lags and do a bunch of other preparatory work, so I don’t even want to consider this technology in detail.

Installation of insulation

I have already said that I agreed with the client to insulate both the floors on concrete floors and the floor in the basement on the ground. So I’ll tell you how the concrete floor is insulated with foam plastic under the screed in both cases.

On the ground

I always start work by stocking up necessary tools. In this case I need:

gravel or crushed stone with a fine fraction;
river or quarry sand;
laser level (you can use water);
electric tamper (can be replaced by a manual one);
mesh for reinforcing the surface of the screed (metal);
cement;
metallized adhesive tape;
material for waterproofing surfaces;
beacons for leveling the surface of the screed;
alabaster;
aluminum rule;
slabs of extruded polystyrene foam, that is, penoplex.

To make a high-quality screed, I deepened the soil level in the basement by about 50 cm. Moreover, I leveled and tamped the bottom of the pit very efficiently and carefully. If the soil is loose, it will subsequently shrink and the floor in the basement will simply fail.

Further work is carried out in the following sequence:

I waited for the complete drying of the soil in the basement. Before starting work, its surface must be completely dry. To make this happen as quickly as possible, I opened all the windows under the ceiling and doors in the basement, providing high-quality and intensive ventilation.

I covered the floor surface with a layer of dry gravel. To avoid shrinkage, I did it in two stages. First, he poured gravel in 20 cm, after which he tamped it with a rammer. Then he poured another same layer and leveled it too. But in the latter case, I set the laser level and used it to check the border of the embankment so that it was without height differences.

Sand was poured on top. It should be a material with an average grain size. The thickness of the layer is 10 cm. I carefully compacted it with a rammer and again checked the level of the filling. In some places it was necessary to fill up a little.

Installed foam boards. I laid them on the sand because I was insulating the floor in the basement, which, although they will walk, but not as often as, for example, on the first floor.

Penoplex has edges processed in a special way, so the plates are joined to each other very tightly, excluding the formation of cold bridges. I laid the insulation, starting from the stairs, so as not to distort the surface of the sand, which I had leveled before.

After laying out the insulation and carefully matching all the joints (by the way, I placed them in a checkerboard pattern), I additionally glued all the seams with a metalized adhesive tape.

If you are making a floor on the ground that will be used intensively, you must first make a rough screed, and then insulate it.

Put the second row of insulation boards. As I said, you need a layer of insulation 10 cm thick. But I take sheets of 5 cm and put them in two layers so that the seams do not coincide with each other. Then no cold will definitely seep inside.

When laying both layers, I always use a laser level and check how evenly and correctly the foam boards are laid out. Then it depends on how much effort will have to be applied to level the screed.

A waterproofing membrane was laid on top of the insulation boards. By the way, you can replace it with ordinary plastic wrap.

In my case, the basement was quite large, so I had to use several sheets of film. I arranged them in such a way that the edges of adjacent sheets overlapped each other at a distance of about 10 cm (otherwise the solution will flow into the foam).

I also fastened the sheets of polymer film with adhesive tape so that they do not fidget on the surface, and the waterproofing layer itself was as tight as possible.

I wrapped the edges of the film on the walls to form a kind of rim about 15 cm high.

He put a reinforcing galvanized mesh on the insulation. You can replace it with a composite one.

I placed the mesh on the surface of the insulation so that the reinforcing frame rises slightly (by about 2-3 cm). For this I used pieces of plastic. But you can replace them with a special mesh mount. Penoplex is so strong that brackets for a reinforcing frame can be screwed into it.

He set up beacons for arranging a finishing screed. These are galvanized parts that can be purchased at a hardware store.

I keep the distance from the wall to the last lighthouse at 15 cm, and between neighboring lighthouses - 1.5 meters, since I have a slightly longer rule. Lighthouses must be set in parallel and so that their edge is located strictly on the same level.

I fix beacons on alabaster mortar. To do this, I put heaps of alabaster mortar in one line along the wall, after which I fix the beacon and set its level. In the same way I put the lighthouse along the opposite wall. And then I pull a rope between them and already orient the intermediate beacons along it.

Mixed the screed mixture. I took one bucket of cement and three buckets of sand, then mixed them together in a concrete mixer and added water until the solution became like a not very thick paste.
If you plan to make a floor screed of a large area, you can increase the number of components, but at the same time observe their ratio to each other. And you can still buy a dry mortar for the screed, and then dilute it with water on the spot.
Made a floor screed. The thickness of the screed over the insulation is about 5 cm. But again, remember that I did the floor in the basement, where people will not walk very often. And on the ground floor, for example, or in the garage, I would advise making a layer 10 cm thick.

Then, when it all hardens, it will be possible to mount a decorative flooring. But this work was no longer within my competence, I had to insulate the floors on the first floor, where reinforced concrete slabs overlap, which means that the technology will be applied somewhat differently.

By overlap

I tell you how to insulate the floor on the floor slab with foam plastic with your own hands (for example, on the first floor with a basement or on the second floor).

I brought with me the following tools:

building level;
polymer-based putty;
priming composition;
film for waterproofing;
insulation - penoplex;
polyurethane adhesive;
self leveling compound.

The workflow in my case was as follows:

Checked the entire floor surface for damage. I sealed the seams between the plates in those places where they cracked, knocked down a few tubercles (fortunately, there was a perforator in the house, since I forgot my own) and puttied a few cracks. For this, a polymer putty was just needed.

If you have not found any defects, simply clean the surface of debris and foreign objects. I also always dust the floor slabs with a vacuum cleaner.

Primed the surface of reinforced concrete slabs. This process will get rid of dust on the concrete surface and improve its adhesive properties before gluing foam boards.

I go through the primer twice. In this case, the second time after the first layer is completely dry.

I glued the foam boards to the surface. To do this, I take a sheet of insulation, apply an adhesive composition on its back surface and press it tightly to the surface. I do the same with the rest of the details, placing them so that the seams are spaced apart. One layer of insulation is enough here, since I also insulated the basement.

It should be noted here that in my case the floor was already flat (as there were floor slabs). If your floor has differences in height, then you need to level it not with a heater, but with a rough screed or self-leveling mixture (depending on the height difference) even before starting work on insulation.

He covered the plates on top with a waterproofing film. I laid several sheets of polyethylene with an overlap of adjacent panels on top of each other at a distance of 10 cm. Then I glued them to each other with adhesive tape.

I made a screed from above using a self-leveling compound purchased from a store. After it dries, you can mount the floor covering.

In several rooms, I also made insulation for underfloor heating and installed the pipes themselves for it. But today I will not talk about it.

Summary

Thus, the concrete floors are insulated with the help of penoplex. But there is another interesting way - floor insulation with expanded clay under the screed. You can learn more about this from the video in this article.

Or maybe you know a more economical and effective method screed insulation? If so, I will be glad to hear about it in the comments to this material.

In houses built on the ground, as well as in old buildings, the issue of heat conservation is acute. Knowing how to insulate a concrete floor in a private house, you can not only save on the resources of the heating system, but also minimally affect the technical characteristics of the residential area. Heat retention performance can be improved by using various materials, the choice of which determines the complexity of creating a thermal protective layer.

Why insulate

Concrete floors have the main feature that is unpleasant for the inhabitants of a residential building. They serve as an effective cold bridge. Concrete quickly conducts heat, giving it to the environment. As a result, the first floors of houses built on the ground constantly have cold floors, heating costs increase, and overall comfort for the inhabitants decreases. A similar problem is observed in buildings where there is an unheated basement.

By insulating concrete floors, you can achieve additional benefits, in addition to improved thermal performance. Short list looks like that:

condensation disappears at the boundary of the separation of warm (air in the room) and cold (concrete floor) environment. This increases the life of the floor coverings, prevents the lagging of tiles, the adhesive composition of which is not exposed to excess moisture;
the risk of reproduction of fungus and mold, as well as other microbiological formations that are unsafe for the respiratory system and human health in general, is sharply reduced;
in rooms with insulated concrete floors microclimate indicators are stabilized. Excessive humidity and other deviations from the norm are not observed.

But the main thing that you can get by knowing how to insulate a concrete floor in a private house is to reduce heating costs and elevated level comfort in the rooms.

The mechanics of insulation

When floors are insulated in a private house, there are two mutually exclusive cases. The first is to maintain the height of the ceilings. This may be necessary if the gap between the floor and the ceiling of the upper floor cannot be reduced in order to conduct the gas pipeline to a private house. The second case does not imply strict requirements for the level of the floor.

When it is impossible to change the height of the ceilings, the following solution is resorted to: insulation is carried out from below the concrete screed, the surface of which is the basis for the floor finish. This is not always possible or convenient. In houses built on the ground, expanded clay bedding is used, formed on sand cushions. Fibrous materials, such as glass wool mats, can also be laid.

When insulating a concrete floor from below, you will have to completely dismantle the existing screed. Work will need to be carried out in confined space. In the case when insulation is done from the basement side, all operations will have to be carried out by attaching thermal insulation materials to the ceiling, waterproofing them, the total cost of the process is high both in terms of money and labor costs.

Most often, floor insulation in a private house is done on top of the existing concrete flooring. In this case, apply:

fibrous materials such as glass wool, rock wool, basalt wool;
sheet foamed and extruded materials: polystyrene foam, expanded polystyrene;
rolled polymer thermal insulators: foamed polyethylene, penofol;
sprayed materials: penoizol, special building foam;
bulk materials: expanded clay, perlite, polystyrene granules.

Each of the methods has its own effect on changing the level of the floor. In addition, due to the different mechanical characteristics of the products used, only certain options for laying the outer covering are available for a given material, which will serve as the basis for the final floor layer.

It does not matter how to insulate the concrete floor in a private house. In any case, the existing concrete screed must be cleaned, all cracks are sealed on it, and decaying areas are removed. Draft waterproofing is also done by applying bituminous mastic.

Working with fiber insulation

Mineral, glass, basalt wool is supplied in mats. Various material thicknesses and densities are available. But one thing remains unchanged. The mechanical strength of fibrous materials is not high enough to serve as a reliable base for the topcoat placed on top. Therefore, the work is carried out according to the following methodology:

a waterproofing agent is laid on the existing concrete surface - a dense polymer film, overlapping by 10-15 cm, the joints of the strips are glued with a wide adhesive tape;
lags are laid;
the height of the lag is selected according to the fibrous insulation used. It can be stacked in one or more layers;
the distance from one log to another also depends on the insulation. Its strips should lie between the beams or the board without gaps.

A one-sided membrane is laid on top of the insulation to remove condensate. It must remove moisture from the fibrous insulator. A load-bearing surface is laid on top of the log, it can be sheets of plywood, floorboard, OSB, chipboard. Further actions depend on the goals set by the owner of the house. However, it should be noted that the Smooth surface from plywood is suitable for laminate flooring, laying tiles, and other finishing floor coverings.

If a self-leveling floor is planned, its construction on a surface formed from plywood, chipboard or boards is carried out with mandatory waterproofing. Fibrous materials should not be exposed to moisture, as they reduce volume when wet and lose their thermal insulation performance. For cases where it is impossible to provide complete hydroprotection, special grades of high-density basalt, mineral wool, with hydrophobic properties, are used.

Work with polystyrene, polystyrene

Foam molded polymer materials are used provided that a concrete screed is created on top of them. This method of insulation is characterized by low cost and simplicity. It is preferable if a floor heating system is being built. The list of work in progress is as follows:

the base is leveled by adding sand, a thin layer;
sheets of polystyrene or expanded polystyrene are laid on it end-to-end, the gaps (if there are gaps of 5 mm or more) are foamed;
a special construction tape is glued around the perimeter of the room;
the entire surface of the insulation layer is covered with strips of a dense polymer film with an overlap of 10-15 cm, with a 10-15 cm approach to the walls;
the joints of the strips are glued with a wide adhesive tape, after which a damper tape 20 mm thick is placed around the perimeter of the room.

After completing the above work, everything is ready for laying. cement screed, installation of a warm floor system or pouring self-leveling compounds. Foamed polymer materials create a sufficiently even base so that a layer of concrete or bulk mix can be made to a minimum thickness.

Working with spray materials

The use of sprayed heaters requires the use of special equipment, where the polymer mixture is mixed with carbon dioxide under high pressure. Logs are laid on the concrete base before applying the foam. In the course of spraying between them, the polymer composition increases in volume, after its solidification, if necessary, trimming is done at the level of the timber.

After the foam insulation has been applied and the time declared by the manufacturer of the mixture as the recommended curing time has passed, a coating of plywood, chipboard, OSB is laid on the logs. This method of creating a surface for a screed, self-leveling floor or finishing coating of laminate, tiles is similar to the process of using fibrous materials.

Working with bulk materials

Expanded clay, perlite, polystyrene granules can be a good way to insulate the floor only in cases where the rise in its level is not critical. The following works are being carried out:

a pillow 100 mm thick (minimum value) is poured onto the prepared base;
a rough concrete screed is formed on the pillow, up to 10-15 mm thick;
after complete solidification, a waterproofing layer can be laid on the rough flooring.

On the surface of the rough coating, you can build a floor heating system, make the main reinforced concrete screed or apply a layer of self-leveling mixture. Laying of finishing floor coverings is not recommended.

Working with rolled polymer thermal insulators

Rolled heat insulators, such as penofol, foamed polyethylene, are rationally used only in cases where a slight increase in thermal protection is required. This measure shows good results if concrete pavement underfloor heating system is installed. In other cases, thin rolled thermal insulators do not lead to a significant increase in comfort in the living space.

Materials are laid as follows:

the strips are rolled out and overlapped without entering the walls;
the joints between the strips are glued with foil tape;
a special construction tape is placed around the perimeter of the room.

To heating system underfloor heating or based on the use electrical cables, film heaters showed high efficiency, it is recommended to use foil thermal insulating materials, placing them with the metallized side up.

Choose your insulation method carefully.

The method of laying a heat insulator on top of a concrete floor has the following disadvantages:

condensation occurs inside the insulation layer;
no frost protection
be sure to build two layers of waterproofing, between which there will be a heater;
the arrangement of the final cement screed or self-leveling floor is recommended.

The insulation layer, depending on the selected materials and methods, can have a significant mass, greatly reduce the clearance between the floor and the ceiling, and have other features. Therefore, the choice of a specific option should be entrusted to specialists. They will analyze the task and find the most good way insulation that meets the requirements of efficient use Money and get the best result.

Concrete is a good conductor of heat, but does not hold heat well.. Therefore, from the floor covering, laid directly on the concrete base, it pulls cold. And if a room with such floors is located above an unheated basement, heat will escape through the ceiling.

In addition, due to the temperature difference, condensation forms on the concrete and the humidity level rises. The concrete floor on the ground floor of a private house standing on the ground is also a source of heat loss, especially in the cold season. So concrete base must be insulated.

Concrete floor insulation

To insulate a concrete base, materials with good thermal insulation characteristics are required. If the floors are insulated in apartment building on the second floor and above, that is, below is warm apartment, you can use roll or sheet insulation of small thickness - chemically cross-linked polyethylene foam (PPE, penofol and analogues), technical cork.

For floor insulation in a private house or on the ground floor apartment building insulation of greater thickness and density is needed. The most common options are laying mineral wool or expanded polystyrene (EPS), backfilling with expanded clay. Sprayed thermal insulation is less commonly used - liquid polyurethane foam, penoizol.

Mineral wool is produced in slabs and rolls, PPS - in slabs of different thicknesses and densities. The lowest density and the worst thermal insulation characteristics are ordinary polystyrene foam (polystyrene), therefore for thermal insulation of concrete, extrusion (extruded) PPS is preferable.

When choosing a heater, you need to consider a number of factors:

If a layer of cement-sand screed, leveling agent is applied over the insulation layer, materials with high density and mechanical strength should be used.
If a screed is made of plywood and other sheet materials, it is acceptable to use a lower density insulation
If the insulation will be exposed to moisture, a moisture-resistant and moisture-proof material is preferable - XPS or hydrophobized mineral wool
In a private house where rodents are found, it is better not to use foam
Expanded clay insulation is not suitable for rooms with low ceilings, where it is highly undesirable to increase the height of the floor, but is the best solution if the floor needs to be raised
For the application of sprayed thermal insulation, special equipment is required.

If in the conditions high humidity a heater is used that is not distinguished by moisture resistance, it is mandatory to protect it with a layer of waterproofing. Waterproofing is also required. plate heaters top before wet screeding.

Concrete floor insulation options

In an apartment building on the ground floor, the floors must be insulated, on subsequent floors, such a need usually arises if it feels cold from the floor. This situation is typical for houses of old buildings, where the finish coating is laid directly on the concrete floor slab.

Also, the thermal insulation of the base is necessarily carried out during the installation of the floor heating system, so that the heat goes up, and does not flow to the neighbors from below. If the work is not carried out in a new building, where the finishing floor is not laid, then the insulation is usually preceded by the dismantling of the floor covering (an exception is situations when a raised floor is being made).

Regardless of the chosen insulation and insulation option, the concrete base must first be examined, cracks repaired, mortar sagging removed, dust and debris removed.

Polyethylene foam insulation

The main purpose of penofol is a soundproof and shock-absorbing substrate; it is not suitable for full thermal insulation of floors above an unheated room. But if you lay it on a concrete base in the apartment, the temperature of the flooring will become more comfortable.

It is a moisture-proof and vapor-proof material, and waterproofing is not needed when laying it. Foil or metallized penofol is used as a substrate for underfloor heating, it must be laid with a reflective layer up.

The rolled material is rolled out on the prepared base, the strips are laid end-to-end. Penofol is attached to the base with double-sided tape. If a material with a self-adhesive base is used, you just need to remove the protective layer. From above, the joints are glued with adhesive tape; aluminum tape is used for the substrate with a reflective layer.

Most often, foamed polyethylene is used as a floor covering that can be mounted directly on it. If tiles or an elastic coating such as laminate will be laid on top, it is necessary to make a prefabricated screed from sheet materials, and logs are stuffed under the plank floor.

Warming under wet or semi-dry screed

The best insulation under cement-sand screed is extruded polystyrene foam. To insulate the floor, you need to choose EPS of maximum density with minimum hygroscopicity, for example Penoplex-35 or 45. Due to its light weight, in combination with a screed, it does not exert excessive load on the floor.

Sequence of work

Prepared, hardened and cleaned base is primed with a deep penetration compound, if the concrete is porous, the application of the primer must be repeated
On the first floor foundation waterproofing with access to the walls using mastic or roofing felt, on other floors this stage can be skipped
around the perimeter adhesive damper tape, its upper edge should be 5-7 cm above the surface of the future screed
If waterproofing work has not been carried out, the base is leveled using a thin (1.5-2 mm) layer of clean sand
XPS boards are laid close to each other, without gaps, with seams apart. If sand bedding was used for leveling, then each slab should be slightly moved back and forth along the sand layer before laying in place, pressing from above
Insulation waterproofing is carried out thick polyethylene film, its strips are overlapped, the joints are glued with adhesive tape
Above reinforcing mesh is laid with mesh 80-100 mm
Screed in progress

Warming along the lags

Such insulation is performed under. There are no wet processes, and the load on the insulation is reduced due to the use of self-supporting sheet materials - plywood, chipboard, OSB, GVL. The best choice for such insulation is mineral wool of sufficient density, expanded polystyrene is also suitable, and if you need to raise the floor level, you can use expanded clay backfill.

If the floors are above an unheated room, the thickness of the mineral wool must be at least 50 mm, above the heated rooms 30 mm is sufficient. The thickness of the layer is best determined based on the manufacturer's recommendations, since it depends on the density of the mineral wool board. You can also use roll materials.

If the floor is insulated above an unheated room, mineral wool is closed on both sides with a waterproofing vapor-permeable membrane. Diffuse membranes are single-sided and double-sided, the nuances of their installation are described in the instructions for a specific product.

It is not recommended to cover mineral wool with a vapor-proof film, especially when the floor is insulated above a cold basement. Due to the temperature difference, condensation will form on the side of the film facing the heater, and the thermal insulation characteristics of the mineral wool are significantly reduced when it is moistened.

To prepared, covered with a membrane concrete base logs are attached with anchor bolts. Their step should be 1-2 cm less than the width of the insulation boards. Logs are treated with antiseptic impregnation. If the membrane is not used, strips of roofing material should be laid under the logs on the concrete.

Insulation is placed between the lags. A layer of membrane is laid on top and attached to the logs with a stapler. After that, you can proceed with the installation of the sheet screed.

Expanded clay insulation

If at the base of a private house lies a monolithic concrete slab, and a screed will be made from above, you can insulate the base with expanded clay. One of the options is backfilling with expanded clay and making a rough lightweight screed with the addition of expanded clay to the solution.

The base is waterproofed, it is best to use mastic
Expanded clay is poured with a layer of at least 10 cm and leveled with a long rail. Previously, on the walls, using the level, you need to make marks to control the thickness of the expanded clay layer, rough and finish screed
A reinforcing mesh is laid on top of the expanded clay
A layer of a rough fixing screed 5-8 mm thick is applied and leveled along the beacons. For 1 part of a standard concrete solution, 2-3 parts of expanded clay are taken. Damping pads are pre-attached around the perimeter

After hardening the rough screed, which requires a minimum of 7 days, a regular concrete screed is poured. In the future, it will be possible to insulate it from above with the help of XPS, mineral wool, bulk or sprayed thermal insulation.

In a similar way, it is possible to carry out insulation under the screed on the ground, only a well-compacted cushion of crushed stone and sand is needed (they are covered with a layer of 5 cm), and a durable roofing material is used for waterproofing.

Video

Insulation of the concrete floor with extruded polystyrene foam

Warming with mineral wool along the logs

Expanded clay insulation under a dry screed

Outcome

Insulation of the concrete floor is necessary in private houses and on the first floors of apartment buildings, and preferably in apartments located above. The principles of insulation of an already finished concrete floor in an apartment and a private house are similar, the thickness of the insulation may vary depending on the temperature difference above and below concrete floor. Also on the ground floor, the requirements for waterproofing are higher.

Can be used as a heater various materials, the insulation technology depends on the chosen material and the features of the subsequent leveling of the base.

Under wet and semi-dry screed the best option is extruded polystyrene foam, and if a significant increase in the level of the floor is acceptable, expanded clay. Under a sheet screed, mineral wool is well suited, under a warm floor - foamed polyethylene with a heat-reflecting layer.