Insulation of floors on the ground is a standard solution. The procedure for insulating the floor on the ground. Basic rules for floor insulation

Laying out the floor on the ground is one of the first stages in the construction of a private house. This floor is intended for basements, cellars and other underground premises, and if these are not provided, then for the first floor of the house. For the same purposes, you can install a floor in a ventilated underground, but this is the subject of a separate article.

On the Internet you can come across information about various options floor designs, about several types of “construction pies”. But, as the poet said, “Don’t make life difficult for yourself. It’s already difficult.” Only one option for installing a floor on the ground with insulation for all occasions can be called optimal. " Layered cake» the scheme for insulating floors along the ground from bottom to top looks like this:

1. compacted Sand and gravel,

   thermal insulation,

   technical polyethylene film,

   cement-sand screed,

   finishing coat.

Soil preparation

Before “bake the construction cake”, figuratively speaking, “let’s knead the dough”, i.e. Let's prepare the soil. Let's start by filming fertile layer soil. The thing is valuable, but not intended for construction.

Compacted sand and gravel mixture

This is done to minimize shrinkage. The best backfill option is a sand-gravel mixture. This mixture will need to be compacted. You can use your own boots for this purpose, but in the 21st century, high-quality equipment, for example, a vibratory rammer, is preferable.

The resulting surface should be smooth.

Attention! We got to the main element of the “pie”. Why the main one? Gravel and sand, which we just discussed, as well as polyethylene and cement, which we will talk about below, do not imply a variety of options. Simply put, they are all the same. And the thermal insulation may be different.

First of all, it can be organic and inorganic in its chemical nature. Among inorganic insulation materials, the most popular are the so-called mineral wools: stone wool and glass wool. However, they cannot be used for insulating floors on the ground. They perfectly absorb water, which sharply reduces the thermal insulation properties of materials.

Products made from expanded polystyrene have gained fame as high-quality insulation materials and are widely used for thermal insulation of building structures. However, brittle white foam is used as insulation only in areas where there is little risk of contact with water. But where there is soil, there is groundwater. And the second type of polystyrene foam thermal insulation materials- PENOPLEX®, manufactured using the extrusion method, will be very appropriate. It has zero water absorption, which will keep it intact thermal insulation properties material. It turns out that PENOPLEX® has no alternative for insulating floors on the ground. The numbers confirm this.

Advantages of PENOPLEX®

Let us present a small table indicating the main parameter that determines the heat-protective capabilities of a particular heat insulator - the thermal conductivity coefficient λ. These tables are based on SP 50.13330.2012 " Thermal protection buildings."

The lower λ, the better material suitable for thermal insulation, because conducts heat worse.

In addition to high heat-shielding properties and zero water absorption, mention should be made of the high strength of PENOPLEX® - lightweight, but capable of withstanding up to 27 tons per square meter surfaces. Therefore, it will work perfectly with a cement-sand screed poured above and will withstand all loads.

It is also important to note the biological stability of this material, which is completely uninteresting to harmful bacteria, fungus and mold. Firstly, because it does not absorb water, which is necessary for all living beings, including these. Secondly, it cannot serve as a breeding ground for them. Therefore, mycological tests of PENOPLEX® confirmed its resistance to fungal formation.

Tested material

Each of us expects to live a long and happy life. And in this case, those who build their house thoroughly, using long-lasting materials, are right. PENOPLEX® has been most seriously tested for durability.

In the laboratory of the Research Institute of Building Physics Russian Academy Architecture and Construction Sciences (NIISF RAASN), material samples were subjected to cyclic temperature and humidity exposure. The cycle consisted of two freezing to – 40°C, alternating with heating to + 40°C, and subsequent holding in water. In terms of temperature and humidity exposure, this is equivalent to one year of operation.

PENOPLEX® went through 90 such cycles without changing its shape or its technical characteristics. Taking into account safety factors, the durability of PENOPLEX® is estimated at 50 years. This means that before the next repair of the floor insulation on the ground, more than one generation of residents of the house will grow up.

Installation of floor insulation unit on the ground

The process of installing floor insulation on PENOPLEX® soil is as easy as the material itself and pleasant. Tired of heavy physical work with primer, you will enjoy taking a break while cutting, cutting and conveniently laying PENOPLEX®. This is facilitated by the homogeneous structure of the material (so it does not crumble), optimal size slabs and L-shaped edges along all edges of the slabs, so that they fit well together. The slabs are laid staggered.

Technical film

You can find a lot about this layer on the Internet. smart sayings, but its purpose is simple - to retain moisture in cement-sand screed, so that it gains the proper strength and prevents this screed from getting into the space between the slabs. Therefore, we will make do with a regular polyethylene coating.

Polyethylene rolls are overlapped by 10-15 cm for reliability, and the upper edges are raised up a couple of centimeters.

Cement-sand screed

The work is carried out in two stages. First, a steel mesh with cells of 10x10 cm and a wire diameter of 3-4 mm is laid.

The mesh is placed in the lower layers of the screed so as to be inside it. To do this, it is raised slightly (by 10-15 mm) above the thermal insulation using clamps for the “chair” fittings or others. At large values thickness of the screed, use “chairs” 20-30 mm high.

And then, a layer of mortar is poured to the designed thickness.

Summary

Floor on the ground using reliable and efficient slabs PENOPLEX® will last a long time without loss of technical characteristics. Taking into account its 50-year durability, after installing such thermal insulation of the floor on the ground, more than one generation of residents of the house will grow up before its next repair.

But it is not without a number of shortcomings. If you forget to do strip foundation vents (or incorrectly calculate their cross-section), then over time this can lead to problems. Due to insufficient underground ventilation wooden joists become covered with fungus, mold and rot. Excess moisture in the base also leads to destruction concrete floors floor of the first floor.

To avoid this, you can replace traditional vents with a closed, ventilated underground. This is discussed in detail in the article. “Are vents needed in the basement?” . But there is another option - to abandon the underground and build a floor on the ground based on a strip foundation, as FORUMHOUSE experts advise.

Floors on the ground: what is it?such

This structure is a monolithic concrete base (screed). Here is the construction of the floor on the ground: the screed is poured inside the perimeter of the strip foundation onto well-compacted soil, which is used to fill the foundation sinuses and a layer of insulation. Together with concrete base A heated floor system can be installed. This design accumulates heat, making it well suited as an element of an energy-efficient home.

Floor composition based on soil for a residential building.

The following flooring options are distinguished:

1. A floor slab is poured onto the prepared base (well-compacted soil), rigidly connected to the strip foundation;
2. A floor slab, not connected to the strip foundation, the so-called “floating” screed, is poured onto the prepared base.

Let's take a closer look at the pros and cons of these options.

Mikhail1974:

– If you pour a “floating” screed, this “unties” the structure of the tape and the floor. If shrinkage occurs, the structure of the floor screed on the ground will “play” regardless of the foundation; cracks will not appear in the structure, because no tension. That's a plus. But there is also a minus - the structure “lives its own life”, separate from all other structures.

Floor installation on the ground.

With a rigid structure, the foundation/screed assembly works as a single whole. The screed will not shrink, because lies on the foundation. But if the soil is not compacted well enough, after a while it may sag and the screed will “hang” in the air. Under heavy load, if there are walls, partitions on the screed, supporting elements, this can lead to base deformation, cracks and loss bearing capacity the entire floor structure on the ground.

How to make a floor on the ground

Both screed options have both pros and cons. The quality of concrete floors on bulk soil largely depends on the quality of compaction of the bulk soil and on how correct the design is.

Mikhail1974:

– When pouring a “floating” screed, the “foundation wall/screed” knot must really be untied, otherwise the structure may become pinched in the tape frame. Those. the floor inside the tape frame must move relatively freely, otherwise the whole point of a floating screed is lost.

To do this, a damper is made of an elastic material between the screed and the foundation (wall), which restores its original shape after removing the load - in this case it is appropriate to place an isolon 8-10 mm thick. This will allow the concrete screed to “float” freely and compensate for its thermal expansion.

A common mistake is to tie all the knots as tightly as possible. As a result, increased loads occur in structures. In the case of a floating screed, the “floor” and “foundation” elements work independently of each other.

Floor on the ground: device.Basic principles

Important rule: a well-prepared foundation is the key long term services of the entire structure. The backfill base (the best backfill for the floor on the ground is sand) must be spilled with water and thoroughly compacted in layers of 10-15 cm. In order to properly compact the base, filling with crushed stone is used (crushed stone should be laid under the floors in a coarse fraction).

Due to the filling of crushed stone, when a tamper is driven through it, a local impact occurs, as a result of which deep compaction of the soil layers lying at the lower levels occurs. On correct technique sand compaction is worth paying attention to.

– All instructions for vibrating plates say that the plate compacts sand to a depth of 20-30 cm, but I doubt that this layer is compacted well enough. Therefore, I believe that to be on the safe side, it is better to compact the sand in layers of about 10 cm. It looks like this:

• Spread the sand in a layer of 10-15 cm;
• We walk through the sand with a vibrating plate “dry”;
• We spill the sand with water from a hose. This should be done not with a stream of water, so as not to break the layer, but through a spray nozzle;

You need to spill water so that the sand is wet, but not oversaturated with moisture. If the amount of water is too large, the sand base will practically not be compacted.

• We walk through the moistened sand with a vibrating plate 2 times, changing the orientation of the movement;
• We spill the sand with water again;
• We walk through the moistened sand with a vibrating plate 2-3 more times, changing the orientation of the movement.

What kind of waterproofing to put on the floor on the ground

After thorough preparation of the base, we begin laying hydro-vapor barrier, which will protect the floor structure from moisture. People often ask whether it is necessary to make a footing before laying this layer. After all, in order to avoid damage, welded or glued waterproofing must be placed on a flat, rigid base.

It is necessary to insulate floors along the ground, since there is no flooring will not protect you from the cold that comes directly from the ground. And in the opposite direction the heat will leave the house. The thermal insulation layer in ground floors must be of sufficient thickness and economically feasible so that heat loss through the floor complies with the standards (SNiP).

Thickness of the thermal insulation layer

For unheated floors, a minimum of 10 centimeters of polystyrene foam will be required in moderate climates. And with the “water heated floor” system, it is recommended to lay at least 15 cm of polystyrene foam, since the temperature difference through the insulation layer can reach 25 - 30 degrees, and each added centimeter significantly reduces heat loss and saves money.

Floors on the ground are made in accordance with design solutions, on stable soils, after geological research. This design must ensure the stability of the foundation during frosty ground movements, i.e. immobility of the foundation relative to the ground inside the house.

Before we talk about insulating floors on the ground, let’s take a closer look at their design.

How to make floors on the ground

Insulation of floors on the ground will not make sense if the floors themselves are made in violation of the technology - the structure is made of many layers.

The diagram shows the following.

1. The first layer is the mother soil, which is located inside the perimeter of the house and was not removed during construction. construction work. It is leveled and compacted using a tamping plate (machine).
2. Bulk layers of soil 20 cm thick serve to raise the floor level to the required height. Each layer is compacted after backfilling. The thickness cannot be more than 20 cm, so that the compaction by the machine is of high quality.
3. A layer of coarse crushed stone (fraction not less than 50 mm). Topping with crushed stone is done 10 - 20 cm thick, after which it is compacted by machine. The purpose of the layer is to compact the soil as much as possible. When compacting crushed stone, point, very large loads are created on the soil, and it becomes compacted.
4. Leveling with sand or weak cement-sand mortar (preferred). The layer is needed to level the surface of the crushed stone in order to create a flat area for laying waterproofing. The sand is poured abundantly and compacted.
5. A layer of vapor and waterproofing. Its purpose is to prevent the floors and the entire house from being wetted by steam that comes out of the ground. Vapor and waterproofing plays key role throughout the entire structure. The safety of the floor covering, walls, the house as a whole, and the thermal insulation of the floor will depend on the quality and reliability for the entire period of operation.

   Therefore, for steam and waterproofing they choose only quality materials, specifically designed for this purpose. A special long-lasting vapor barrier membrane can be used, or roofing felt in two layers can be used. The flooring is carried out with an overlap of individual parts by 30 cm, the turn on the walls is made of the same length.

6. We will consider the insulation layer below. It is usually covered with a plastic film, which serves to prevent the solution from getting into the cracks between the insulation boards, and so that “if something happens” the insulation can be removed from under the screed undamaged.
7. Screed - main load-bearing element floor structures on the ground. It must be made reinforced and always durable. It redistributes the pressure that is exerted on the floors in the house over a larger area of ​​soil. The screed is poured lightweight concrete or cement-sand mortar high strength with a thickness of at least 5 centimeters.

   It is usually reinforced with a mesh with a cell size of 5-7 centimeters and a wire thickness of 2-3 centimeters, laid at a height of 1-2 centimeters. In the case of creating heated floors, the screed is made using a special technology, the mesh is placed on polyethylene, and a pipeline with a coolant laid in a special configuration is tied to it. Fiber fiber binders are added to the screed, as well as plasticizers to impart strength and elasticity during thermal expansion. The screed is also divided into small squares with seams 2 cm wide to prevent critical tension.

8. Flooring. Any floor covering can be laid on ground floors. And with " warm floors» can only be combined special types floor coverings.

Choosing insulation that does not accumulate water

Let's take a closer look at the issue of choosing insulation for floors on the ground. Quite a lot of heat insulators suitable for screed are advertised on sale. They have different names, but this variety is deceptive, under different names basically the same thing is hidden.

Fundamentally, all insulation materials are divided into two large classes - steam-waterproof and those that are saturated with water and allow water vapor to pass through them.

It is advisable to lay vapor-proof materials under the floor screed on the ground. Mainly due to the risk of breaking the vapor barrier from the ground. Because there is no ventilation for the insulation in this design.

Beware of mineral wool slabs

As you know, without ventilation, insulation that allows steam and moisture to pass through is not permissible, even in places where the occurrence of excessive humidity is unlikely.

Therefore, the purpose of durable mineral wool slabs, which, by the way, are advertised for sealing under screed, is not entirely clear. The dew point in the construction of floors on the ground will be exactly in the insulation; it can become saturated with moisture through the concrete both above and below, and will lose its properties.

Therefore, the choice falls exclusively on a vapor barrier - an insulation that will not care what kind of vapors move and where, and will not lose its properties from their influence. Basically, extruded polystyrene foam is used under the screed.

Possible options

• filling with polyurethane foam high density. But with it it is more difficult to create the upper flat surface. We need special technology, which makes the work even more expensive.
• Very durable foam glass is suitable. But it is many times more expensive, and its layer will require 2 times more higher coefficient thermal conductivity, in addition you need to carefully look at the load and strength of the material itself….

In general, there is currently no reasonable alternative to polystyrene foam under the screed.

Selected features of creating an insulating layer

The thickness of expanded polystyrene should not be less than 10 centimeters, or heat leakage into the ground will be too significant, the design is considered by standards not to be economically feasible.

But it is advisable to increase the thickness of this insulation in floors on the ground even more - up to 15 centimeters. A one-time cost that will pay off later. After all, the house should be used for a very long time?

Typically, insulation is laid in two layers, with the seams in the top layer offset relative to the bottom. All cracks are sealed with scraps of polystyrene foam and its shavings.

Use together with insulation vapor barriers is not allowed. polyurethane foam. It is saturated with moisture as easily as mineral wool, but at the same time it loses its structure and collapses.

Along the contour of the room, polystyrene foam boards are installed, 3 cm thick and high at the level of the screed. Those. The screed should not touch the walls anywhere.

Also if linear dimension the screed exceeds 3 - 4 meters, it is recommended to break it with a 2 cm wide seam, which is filled with polystyrene foam to maintain integrity during drying and temperature changes.

Ground floors, properly insulated, are an excellent basis for any floor covering.

Thermal insulation of floors in a private house is associated with the design features of the house. It can be with or without a basement. In the latter case, the floor is installed on the ground, with a screed or concrete slab laid separately from the walls. However, concrete, of course, cannot protect against the cold and provide comfort in the house, so insulation is necessary.

This installation option is not suitable for all places, for example, if the water level in the ground is high, or they have soil with a loose structure and can swell.

The installation of floors is a multi-layer structure, in which the installation of insulation is a mandatory measure.

Features of the technology

This type of thermal insulation is considered one of the most effective, but at the same time very labor-intensive. It's connected with preliminary preparation soil under the building. The specificity of the installation of the insulating layer is the absence of a rigid connection to the walls of the building. Therefore, in addition to thermal insulation, you should pay attention Special attention for minimal shrinkage of the entire structure during further operation.

In the vast majority of cases this type insulation is used for belt type foundation. It should only be performed after final hardening. supporting structure building. There is a certain scheme for performing work, which consists of the following stages:

• Soil preparation. It consists of treating the soil layer by thoroughly compacting the surface.
• Backfill made of gravel and sand. This layer is necessary for minimal shrinkage of the structure, and will also partially perform waterproofing functions.
• Concrete pad. The base on which the insulation will be installed.
• Installation of the first layer of moisture insulation. Required for high levels groundwater.
• Thermal insulation layer. May consist of insulation various types, ranging from available natural materials and ending with modern polymer structures.
• Secondary waterproofing layer. Installed only for thermal insulation materials with hydrophobic properties: basalt wool, expanded clay, a mixture of clay and wood chips.
• Concrete screed with reinforcing mesh. It is the basis for installing a finished floor.

Compared to other insulation methods, this technique is characterized by increased labor intensity and strict requirements for all layers. As a result, they should form an effective and reliable floor insulation cake. Therefore, the order of its arrangement should be considered in detail.

Layer options

Insulation of the floor on the ground is carried out in two ways: they differ in the design of the underlying layer. The main criterion for choosing the number of layers when insulating a floor is the composition of the soil and the groundwater level. If there is a possibility of raising the latter to heat-insulating layer– should be provided additional measures waterproofing. In each case, the floor insulation device must comply with a specific scheme.

Concrete base layer

Such a floor insulation cake can be considered basic. The design of this flooring option includes the following layers.

• Compacted. Often the soil that was removed when digging the foundation, of course, except for black soil and peat, is filled back in. Moreover, it is compacted every 200 mm times. This is one of the measures to eliminate or at least reduce the risk of cracking of the future floor.
• Compacting with crushed stone. Moistened crushed stone of a fraction of 20-60 mm is covered with a layer of 70 mm, leveled and compacted with a tamper. Its main task is to further compact the soil.
• Underlying concrete. It would be more correct to consider lean concrete a technological rather than a structural layer of the pie. It is used as a basis for waterproofing. Optimal thickness at the underlying layer - approximately 60–70 mm. M100 concrete is used for its production. The concrete is laid evenly, without sudden changes, since this determines the density of the insulation and waterproofing.

On a note

After laying the insulation, the height difference should not be more than three to five millimeters per 2-meter strip.

• Waterproofing. In the role waterproofing material, as a rule, a built-up roofing material, polymer-bitumen or PVC membrane or simple polyethylene film laid in two layers.
  Insulation. The main insulation is usually laid horizontally dry. The quality and integrity of thermal insulation is determined by the thoroughness of the joints between sheets or slabs. Cold bridges may form on the side of the foundation walls. To eliminate this phenomenon, it is necessary to additionally lay 40–50 mm of insulation vertically. Secure it with dowels. The upper surface of the main insulation layer should be located at a level corresponding to the horizontal waterproofing of the foundation. There are several options for choosing insulation.
• Vapor barrier. The most optimal solution in terms of quality/price ratio, these are polymer-bitumen membranes based on polyester and fiberglass. PVC membranes are more durable and do not rot, however, this material is also more expensive. You can perform a vapor barrier from polyethylene film, laid necessarily in two layers.

Attention

Polyethylene film can be easily damaged during the concrete pouring process, and it is almost impossible to control its integrity.

• Cement strainer. It is made from M100 mortar and reinforced with a wire mesh ø 4–6 mm, and the cell size is 100 by 100 mm.

sand cushion

The difference between such floors is the absence of concrete preparation, which is replaced by laying a 150 mm sand cushion. The sequence of constructing the floor pie is the same. With this option for installing ground floors, it is, of course, more difficult to ensure that the base is even across the entire surface.

Methods of thermal insulation of floors

Depending on the required thermal insulation indicator, it is necessary to select best option insulation. Until recently, the choice was not particularly large - expanded clay or a mixture sawdust and clay. But with the advent of modern polymer materials it became possible to use different ways heat preservation when laying a floor on the ground. But first, let's look at the already classic method - insulating the floor with clay and sawdust.

Its advantage lies in the low cost of its constituent elements.

At the first stage, natural clay must be mixed with water and a liquid solution must be prepared. It is best to use a concrete mixer for this. Pre-clean dry clay from debris. Approximate ratio 1:5 (water/clay). The resulting mixture should sit for 2-3 days. This is necessary for complete dissolution. You need to periodically add water to the container and stir. Before applying clay to the waterproofing surface, dry sawdust is added to it - about 20% of the total volume.

The resulting mixture must be evenly distributed over the surface of the subfloor. The optimal layer thickness should be about 10 cm. However, due to high humidity It takes about 3 weeks for the liquid to evaporate from the clay layer.

However, the use of this method is currently not recommended, since the degree of thermal insulation will be extremely low. Insulation of the floor on the ground is best done using special materials– polystyrene foam, basalt wool or polystyrene foam. In this case, the final result will correspond to optimal thermal savings.

Expanded polystyrene

The structure of polymer polystyrene foam is in many ways similar to traditional polystyrene foam. The same initial components are used for it. The difference lies in their subsequent processing. To achieve a good density, the material is subjected to external heat and pressure. This method is called extrusive.

As a result, the insulation acquires the following unique properties, which can be used for arranging floors on the ground:

• High degree thermal insulation. The thermal conductivity coefficient varies from 0.025 to 0.032 W/m*K. For installation on a prepared ground base, sheets with a thickness of 50 to 100 mm will be required, which is significantly less than a layer of expanded clay or sawdust;
• Waterproof. The main problem with the operation of a dirt floor is the high humidity level. Expanded polystyrene has no high level hygroscopic and almost completely impermeable to moisture. This will protect wooden surface;
• Easy installation. Installation requires a minimum of tools. The structure is easy to process and, unlike foam, has good mechanical strength.

During installation, the seams between the sheets should be carefully insulated. Through them it is possible not only heat losses, but also groundwater penetration.

A 30-centimeter layer of gravel is laid at the base of the floor, which is then covered with a 10-cm-thick concrete screed. There are two options for laying polystyrene foam slabs.

PSB slabs are laid on waterproofing: if the material is thin - in two rows, observing the bandaging of the seams, if thick - in one. The total thickness of the thermal insulation is 10 cm. Next, a screed (cement) with a thickness of at least 4 cm is placed on top of the polystyrene foam. The screed is reinforced with polymer or steel mesh and lay the flooring on top of it.

The difference between these options is the sequence of layers of hydro- and thermal insulation. When laying waterproofing on top of insulation slabs, the solution when pouring the screed does not fall between its slabs and thus eliminates the formation of cold bridges. In this case, it is very important to calculate the total thickness of these layers so that the levels of waterproofing and horizontal insulation of the walls coincide.

Extruded polystyrene foam

Plates made of this material are harder, so they are able to withstand significant loads. It is laid on gravel. Low moisture absorption makes it possible to use them in places where the soil has a high water level. The thermal conductivity coefficient of the insulation is quite small, so the thickness of the thermal insulation can start from 8 cm.

Polyurethane foam

IN in this case Of all the options for polyurethane foam boards, the most rigid ones are suitable - PUR and PIR, more modern material. This material has a homogeneous structure with closed cells. There are also slabs covered on both sides with fiberglass or aluminum foil. Thus, the thermal insulation properties of polyurethane foam boards increase, and its vapor permeability decreases. The slabs are laid on waterproofing. Given the low thermal conductivity, thinner slabs can be chosen. Laying slabs is often replaced with sprayed polyurethane foam.

Mineral wool boards

Mineral wool slabs must be rigid, which are characterized by resistance to deformation and high density. The material is laid, like expanded polystyrene, in one or two layers. To reduce water absorption, the slabs are treated with a hydrofibizing agent. For a layer of mineral wool insulation, a thickness of 10 cm is sufficient.

The fibrous structure of mineral wool requires insulation not only from the ground, but also from layers laid directly on it.

Expanded clay

This material has a light and porous granular texture. To make it, clay that is crushed and fired in a special way is used. For insulation on the ground, expanded clay of fraction 8-16 mm is chosen. When backfilling a thick layer of material, additional waterproofing may not be installed.

Expanded clay in the floor structure replaces layers of gravel, screed and thermal insulation. Fill it up, layer by layer (thickness 15 cm), compacting it. To facilitate the work, after laying the expanded clay, it is poured with a thin layer of concrete. The next day, a “crust” forms on the surface, on which waterproofing is laid.

Penoizol

This liquid foam, which after application acquires sufficient rigidity. To install it you will need special equipment. After pouring, a porous structure is formed with good thermal insulation properties.

For preparation you will need two components - urea resins with additives and a foaming agent. After mixing them under pressure, the temperature of the liquid can rise to +70°C. This process must be controlled.

After filling all the voids, the interlayer acquires following properties:

• Thermal conductivity - from 0.031 to 0.040 W/m*K;
• Does not react to organic solvents, fungus or mold does not form in its structure;
• Low bending strength. Installation of a protective surface is required.

Due to the complexity of installation, penoizol is used only for insulation large areas. In the case of arranging a floor on the ground for a house with an average area, its use is impractical.

Non-standard options for floor insulation on the ground

Probably, no one needs to be convinced that the floor on the first floor of a private house should have reliable thermal insulation. This is also important for creating comfortable conditions residence, and from the point of view of maintaining the health of all family members. Besides, efficient system insulation of all building structures own home- this is the key to economical consumption of energy to ensure the operation of the heating system in winter, other climate control equipment- in any season. Yes, and the durability of the structure itself is correct organized system thermal insulation also has a significant impact.

On the first floors of private houses, floors are often installed directly on the ground - this, for example, is typical for buildings on a strip foundation. Exists whole line methods of their thermal insulation using various insulating materials. But in any case, it is necessary to determine in advance which layer of insulation will be sufficient so that one can safely declare the usefulness of thermal insulation.

Let's try to understand this issue: insulating the floor on the ground - calculating the thickness of thermal insulation, for example.

Principle of calculation

It would be a big mistake to believe that you can insulate any building structure, as they say, “by eye.” It’s good if you’re lucky and guess right, but the likelihood of such luck is low, you can make a mistake in one direction or the other. Both are bad. The consequences of insufficient thermal insulation have already been discussed above. And its redundancy leads to completely unnecessary waste of materials or complication of the design.

Everything must be based on calculations. Yes, many readers are frightened in advance by the prospect of carrying out any calculations. Let us hasten to reassure them - nothing supernaturally difficult awaits them. Moreover, we will “arm” them with an understanding of the principle of calculation, and convenient calculator, in which you just need to indicate some initial data.

We will not talk directly about the technology for performing thermal insulation work when insulating the floor - this is the subject of a special publication on our website. Let us dwell only on those nuances that directly affect the dimensions of the thermal insulation layer.

How is floor insulation done in a private house?

The task is not easy, but you can cope with it yourself, without resorting to the services of hired specialists. Let the reader be helped by a special publication on our portal dedicated specifically.

So, for insulation to be considered complete, the total resistance to heat transfer building structure(it is also often called thermal resistance) must not be lower than the established standardized value. This indicator is measured in m² × °C / W, and is calculated for each region, taking into account the specifics climatic conditions. The specific value can be found in the SNiP tables, check with your local construction organization or simply take it from the proposed map of the territory of Russia.

Important - for different designs their normalized values ​​have been established. Since we are dealing with floors, we are interested in the meaning “for floors”. To make it easier to navigate on the diagram, these indicators are highlighted in blue numbers.

Now - a small formula that will be required to carry out the calculations.

The thermal resistance of a homogeneous layer of a building structure is equal to:

R=h/λ

h– the thickness of this layer (important – expressed in meters )

λ – thermal conductivity coefficient of the material from which this layer is made (measured in W/m×°C).

Thermal conductivity coefficients are tabular values, the meaning of which can be easily found on reference Internet resources. And for insulating materials, they are, in addition, usually indicated by the manufacturer in the passport data.

The total thermal resistance of a building structure consisting of several layers, including an insulation layer, will be equal to:

Rc = R₁ + R₂ +…+ Rt = h₁ / λ₁ + h₂ / λ₂ + …+ ht / λt

The symbol “t” in this case indicates that these are indicators of the thermal insulation layer.

So, if the value of the normalized thermal resistance is known, if there is an idea of ​​the structure the structure being created floor, it is not at all difficult to determine the thickness of the insulating material that will provide the required level of thermal insulation.

ht = (Rc – h₁ / λ₁ – h₂ / λ₂ – …) × λt

Knowing the thermal conductivity coefficient of the selected thermal insulation material, we obtain its required thickness.

You might be interested in information on how to install

Possible options for floor insulation on the ground

We have decided on the principle of calculation. But now we need to figure out what combination of layers is possible when creating a floor on the ground? And which of them makes sense to take into account?

• Expanded clay is very often used as a thermal insulation material in such conditions. Moreover, it often acts as the only insulation.

(Here and below, diagrams will be shown. Let’s say right away that they are given with significant simplification. In particular, they do not indicate waterproofing layers. Not because they are unimportant, just because thermotechnical calculations it makes no sense to take them into account - the layer is too thin to have any serious impact on the overall insulating qualities of the entire floor “pie”.)

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We go from bottom to top.

1 – layer of compacted soil on which the floor is built. It is not taken into account, since it is precisely from heat loss through the soil (which has a colossal heat capacity and can literally “suck” the heat from the house if the insulation is poor) that all thermal insulation is started.

2 – compacted sand or sand-crushed stone layer. It is not taken into account for the same reason as soil.

3 – layer of expanded clay – this is the thickness that should be calculated. Since the thermal insulation qualities of expanded clay are almost three times lower than, say, mineral wool or expanded polystyrene, the thickness of this layer may require quite impressive.

4 – reinforced concrete screed floor. There is no point in taking it into account, since the thermal conductivity of concrete is very high. And with a screed thickness of only 50 ÷ 100 mm, its thermal insulation qualities will play virtually no role.

5 – finishing floor covering. If natural boards, thick plywood or OSB are used, then this layer can be taken into account when making calculations. The thermal insulation properties of wood are quite good, and this will make it possible to at least somewhat reduce the layer of expanded clay backfill. And conditions are often such that every millimeter of floor lifting counts.

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If laminate, linoleum, and even more so - ceramic tile, then they can be completely ignored in the calculations. Either the thermal conductivity is high, or it is too thin layer, which does not play any role.

• The second option is the use of slab insulation materials. This could be, for example, polystyrene foam various types, special grades of high-density mineral wool, foam glass blocks and other insulation materials.

The diagram can be represented as follows:

What's new in the diagram:

6 is the so-called “ concrete preparation"- thin (about 30÷50 mm) layer of lean concrete. Convenient in the sense that it is easier to perform on such a surface. high-quality waterproofing, and then - laying insulating material. Thermal properties are practically none, that is, they are not taken into account.

7 – layer of selected insulation material. It is its thickness that remains to be determined.

• The third option is the complete use of expanded clay and another, more effective thermal insulation material. High-quality insulation materials often have a very considerable cost, and this approach allows you to achieve certain cost savings.

Read more about how it is produced in a special article on our portal.

There’s probably no need to explain anything about the diagram here - all the same layers that were already mentioned in the first two options. To calculate the thickness of more expensive insulation, you will have to estimate the thickness of the expanded clay backfill in advance.

For the second and third options, a slightly modified scheme can be used. The main insulation under the floor screed is not performed. And on the screed itself, the joists are already being fastened, followed by laying a wooden (plywood, etc.) floor on them. In this option, insulation (slab, roll or backfill) is placed in the space between the joists. The thermal insulation layer changes its position, but, in principle, this does not affect the calculation result.

Everything must have fallen into place, and you can proceed directly to the calculation. That is, to our online calculator. Below we will give some explanations on working with the program.