Which floor insulation to choose? Floor insulation in a wooden house: which insulation to choose The thinnest floor insulation

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

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

Types of materials suitable for insulating concrete floors

If we recall the relatively recent past, then the most affordable insulation used for different designs, was glass wool, and by no means the best quality, so few people decided to use it for insulation of residential premises, and few people seriously dealt with the thermal insulation of floors in apartments. Today, even glass-based wool is of excellent quality, but besides it, manufacturers offer a very wide selection of heat-insulating materials suitable for concrete floors. Among modern insulation materials You can find synthetic, that is, artificially created, natural and mixed materials. Accordingly, those made only from natural components have a higher price.

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

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

Synthetic insulation

Polyurethane foam

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

Expanded polystyrene

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

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

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

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

Ordinary polystyrene foam does not have joint locks, so it is mounted end-to-end, and due to the lack of plasticity, there is no escape from the joint seams, which require additional work. Extruded polystyrene foam is often produced with or without tongue-and-groove locks, that is, with straight ends. Interlocking slabs are used to insulate the floor under a concrete screed to create a seamless coating, and without interlocking they are used for floors along joists - insulation is laid between them.

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

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

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

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

The cellular structure of the materials allows not only to insulate, but also to a certain extent soundproof surfaces. Foam plastic is the leader in this quality, as it has a lower density compared to extruded insulation. But, to be honest, the sound insulation qualities, especially against low-frequency or impact noise, are not particularly outstanding.
Extruded polystyrene foam is a universal material, as it is used for external and internal insulation in almost any area of the building.
Not susceptible to biological effects. Doesn't work well with this insulation mold and other microorganisms-pests.
Easy installation of slabs on any flat surface. Both one and the second version of the insulation can be used to insulate the floor along the joists, as well as under the screed. However, the material is not plastic and if gaps form between the joists and the insulation, they must be filled polyurethane foam, to avoid the formation of cold bridges.
The affordable price of regular polystyrene foam has made it more popular than extruded insulation.

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

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

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

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

The letter “C” in the marking of polystyrene foam means that the material contains fire retardants, which reduce its flammability. However, it must be borne in mind that such expanded polystyrene is much more difficult to catch fire, but if combustion begins, it burns no worse than insulation without fire retardants.

You should choose polystyrene foam PSB-S-35, it is best suited for laying under a screed.
You also need to pay attention to the manufacturer of the product, and if it is unknown, then you should not expect any safety guarantees, either in terms of the composition of the material or its flammability. Best on Russian market Insulation materials from European companies Nova Chemicals, BASF, Polimeri Europa and Styrochem, as well as domestic manufacturers TechnoNIKOL, Penoplex, Thermoplex and Europlex Primaplex are considered.

Polyethylene foam

When it comes to polyethylene foam, the most popular material in this category usually immediately comes to mind - “penofol”. Similar insulation materials can be produced under other brands, with almost identical characteristics, but to consider their features, let’s take penofol as an example.

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

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

This material is often used to reflect heat into the room when installing electrical cables and infrared " heated floors", laying it under the installed heating system.

Penofol is divided into three types:

“A” is a canvas with one-sided foil.
“B” is insulation with double-sided foil.
“C” is a material equipped with a foil layer on one side and an adhesive layer on the other (self-adhesive “Penofol”).

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

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

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

Range permissible temperatures The operating temperature of this insulation for all three types ranges from -60 to + 100 degrees.

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

Penofol prices

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

Polystyrene concrete

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

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

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

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

Polystyrene concrete has the following physical and technical characteristics:

Name of material parameters	Indicators
Density, kg/m³	250-500
Thermal conductivity coefficient, W/(m×°K)	0,075-0,145
Water absorption,% by weight	4,0
Frost resistance (number of freezing-thawing cycles)	F35-F150
Fire resistance, group	G1
Compressive strength	B2.0 - B2.5
Tensile strength in bending, MPa	not less than 0.7
Vapor permeability, mg/m×hour×Pa	0,075

TO positive aspects The following qualities of this thermal insulation composition can be attributed:

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

Laying polystyrene concrete occurs in almost the same way as a regular screed - along beacons. If the floors are laid on the ground, it is recommended to build an embankment of medium-fraction crushed stone under the screed.

If a concrete floor is insulated with this material, then a waterproofing film must be laid under the solution, which will prevent moisture from leaving the solution prematurely, and the concrete will harden and gain strength naturally.

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

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

Insulating the floor in a house is an important procedure that requires a responsible approach. High-quality insulation of a wooden floor will minimize heating costs in winter and ensure a long service life for the floor covering. Currently, the market for insulating materials offers a wide selection of products that can make a person’s life comfortable even in cold climates. However, it is necessary not only to install the insulation correctly, but also to choose it wisely. The fact is that each of these materials has features that allow it to be used in certain cases.

Insulation is carried out during the construction of the house; in this case, there is no need to dismantle the insulating material, and the consumption of building materials and time costs is minimal. But if it is necessary to insulate the floor of a wooden habitable house, then the work here is more difficult to complete. First you need to decide which insulating material is suitable.

Types of insulation

Choosing insulation

The choice of insulating materials is approached carefully. Under no circumstances should you save money on thermal insulation; remember that heat losses in the room entail monetary costs for the ever-increasing price electrical energy for home heating. But what kind of insulation for a floor in a wooden house should be and how to choose it correctly can be determined after you become familiar with the pros and cons of each type of thermal insulation. Popular thermal insulators are:

Ecowool and mineral wool.
Sawdust.
Expanded clay.
Polystyrene foam and penofol.
Polyurethane foam thermal insulation

They differ from each other in features and installation technology. To choose the right type of thermal insulation, several parameters are taken into account:

Temperature and humidity indicators inside a wooden house and the frequency of their changes.
Required thickness of the insulating layer.
Operating conditions of a wooden floor and expected loads on it.
Design weight of the floor structure.

Insulation with sawdust

It should be noted that wood itself is a good heat insulator, however, without an additional insulating layer, wood will not provide high level saving heat in the room. High-quality thermal insulation of the floor is performed using wood sawdust.

This material has a number of advantages, including:

Low price. Buying sawdust will be cheaper than buying mineral wool.
Environmental friendliness of the material. To insulate the floor with sawdust in wooden house the subfloor will need to be covered with material.
The thickness of the layer is from five centimeters or more. The thicker the layer of thermal insulation, the better.
Sawdust can be easily poured into cracks and other hard to reach places, where it is impossible to lay another type of thermal insulation on the floor.

Insulation with sawdust

Advice! Insulation of a wooden house using sawdust is done if you are not afraid of a high level of fire hazard; otherwise, it is wiser to pay attention to a heat-insulating material that has a lower degree of flammability.

Insulation with mineral wool

If you are faced with the question of what is the best way to insulate a wooden floor, in this case ideal solution will become mineral wool. At the moment, such thermal insulation is an attractive solution in terms of price and quality. In addition, mineral wool has many advantages compared to other insulation materials:

Low degree of thermal conductivity, this allows to minimize heat losses in winter.
Excellent level of water repellency. Mineral wool is used as insulation in houses with high humidity; the material does not allow moisture to pass through.
Non-flammability. This indicator minimizes the occurrence of fire.
Long service life. Insulation of a wooden floor using mineral wool ensures a long service life of the heat insulator, which other materials cannot boast of.
Environmental friendliness.
Rot resistant.
Mineral wool is resistant to temperature changes.
Low cost. The price for such a heat insulator is slightly higher than for sawdust, but lower than for most other heat-insulating materials.
Good sound insulation.

A number of disadvantages of mineral wool follow from the advantages. The main disadvantage is considered to be the low level of vapor permeability, because of this water condensation collects on the heat insulator. Therefore, if you choose mineral wool, then think about installing a vapor barrier.

In addition, over time, the mineral flooring cakes, which negatively affects the properties of the wool - the thermal insulation becomes worse. Therefore, during installation, it is recommended to lay mineral wool in two to three overlapping layers. Installation of insulation is carried out without gaps, a vapor barrier layer is placed on top of it, the seams are taped, this step will ensure reliable protection mineral wool to prevent condensation from accumulating on it.

Laying mineral wool

Penofol insulation

This material has not been used for floor insulation for a long time, so penofol has not yet become as popular as many heat insulators. This insulation consists of two layers, the first layer is foil, the second is insulating. Using penofol as floor insulation, you provide many advantages:

Simplicity and ease of installation. Laying such material will not be difficult; you do not need to have professional skills to do this.
The insulation is resistant to mechanical loads.
The insulation has a high density, which allows the material to be laid under a wooden subfloor in a thin layer.
When using penofol as insulation, there is no need to install a vapor barrier, because condensation does not accumulate on such material.

Advice! Penofol has too high cost, however, don’t let this scare you, because the performance qualities of such insulation more than compensate for the price.

To insulate floors using penofol, you must adhere to the following sequence of work:

The first stage is laying a layer of waterproofing.
The insulating material itself is laid on the already laid waterproofing layer.
Joints and seams are securely closed using polyurethane foam.
Next, logs are installed on the insulation in increments of at least fifty centimeters.
Insulation is again laid between the wooden joists, the cracks and seams are again sealed with foam.
Now you can install the boards.

Penofol

Insulating material foam

This type of insulation is on par with mineral wool in its popularity. However, the thermal insulation material differs from the latter in higher performance: it does not cake over time, does not absorb moisture and retains its properties for a long time. In addition, using polystyrene foam as insulation under wooden floors, you will provide the following benefits:

The highest strength characteristics of the heat insulator; it can easily withstand mechanical stress.
Low degree of thermal conductivity. Thanks to this property, even a thin foam layer minimizes heat loss in the room.
Fire resistance.
Resistance to temperature changes and negative impact environment.
The material is not subject to rotting.
Rodents are not afraid of polystyrene foam.

Styrofoam

Insulation material ecowool

When choosing ecowool as insulation, you should know that such thermal insulation will require installation time, unlike the above materials. But such a heat insulator will serve you for many decades and during this time it will reliably retain heat in a wooden house. The disadvantages of the material include its price and the need to use special equipment during the installation process.

Ecowool insulation

Penoplex insulation material

If you are insulating the floor using penoplex, then the installation scheme is the same as laying mineral wool. The insulating material is being installed, the seams and joints are sealed with foam. The insulation can be laid in two or three layers. The use of penoplex provides the following advantages:

During installation there is no need to make a vapor barrier, because condensation does not collect on such a heat insulator.
The material does not require creation additional protection from exposure to moisture.
Resistant to any mechanical stress.
Penoplex is not afraid of rodents.
Has a long service life.

Floor insulation prevents rapid cooling of the room, since heat-insulating materials have low thermal conductivity. Some of them are used for external insulation of the foundation, others for direct finishing of floor coverings inside the house. In the article we will look at the main types of insulation, as well as methods of thermal insulation of concrete and wooden bases.

Features of heat-insulating materials

How to insulate the floor in a house? To prevent serious heat loss in a room, two main types of insulators are used:

Reflecting thermal radiation. These types of heat insulators contain a metallized layer with reflective properties. Due to this, it is possible to significantly reduce the cost of heating the room;
Preventing heat exchange with the external environment. Floor insulation with insulators of this type occurs due to the low thermal conductivity of materials that prevent the exchange of heat in the room with the environment.

To understand the technical characteristics and advantages of modern thermal insulators, let’s look at the most popular ones in more detail.

Organic thermal insulators

Organic floor insulation contains components of natural origin, as well as synthetic binders and cement. Raw materials treated with polymer compounds acquire excellent heat-insulating qualities, fire resistance and high humidity.

What types of organic-based thermal insulators do modern manufacturers offer?

Arbolit.
Pressed blocks are made from wood-based materials, sawdust, straw and chopped reeds. The raw materials also include cement, soluble glass and calcium chloride. The thickness of the blocks can vary from 10 to 100 mm, while they have high bending strength and low thermal conductivity - no more than 0.10 W/m*K; Polyvinyl chloride foam.
PVC boards contain organic resins with low thermal conductivity. Dense and frost-resistant material is used to insulate subfloors, building facades and roofs; Chipboard boards. Chipboards contain an antiseptic and synthetic resins that provide the coating with
enough level thermal insulation and moisture resistance; Polyurethane foam.
Floor insulation is made from polyester, to which emulsifiers and synthetic substances with heat-reflecting characteristics are added. A chemically neutral heat insulator is used to insulate floors above
basement
and soil; Penoizol.
Ecowool.

The heat insulator is made from cardboard production waste. Environmentally friendly bulk material has a high level of thermal and noise insulation. At the same time, ecowool is hygroscopic, so it cannot be used without additional waterproofing.

Inorganic heat insulators Insulating the floor with inorganic insulators allows you to achieve a minimum level of heat exchange with the environment. Synthetic materials are practically not afraid of moisture and strong temperature changes

, so many of them can be used to insulate the base. As a rule, inorganic insulation materials include the following components:
Asbestos;
Plasticizers;
Fiberglass;
Slags;

Rocks.

What types of thermal insulators are in greatest demand? Mineral wool. Manufacture roll material
from waste obtained during the casting of non-ferrous and ferrous metals. The binding component is phenol, which gives the insulation the necessary properties. Mineral wool practically does not burn, has good noise and heat insulation and has high vapor permeability; Ceramic wool.
The raw materials for the manufacture of cotton wool include metal oxides, silicon and zirconium. It can withstand temperatures of 900 degrees or more. The thickness of the thermal insulator layer varies from 5 to 50 mm, which significantly expands the scope of application of cotton wool. It can be used to insulate concrete and wooden foundations, roofs and walls;

Glass wool.

The heat insulator is produced from glass production waste. Unlike mineral wool, the thickness of glass wool is much greater and can reach 60-80 mm. The coating is chemically neutral and is not affected by high temperatures.

Foil insulators

Insulating the floor with foil insulators allows you not only to prevent serious heat loss in the room, but also to provide additional noise and waterproofing. The thickness of the materials is relatively small and ranges from 4 to 100 mm. This insulation consists of two or three layers, one of which is made of aluminum foil.
Penofol.
and soil; The combined type heat insulator is made of metallized film and polyethylene foam. The coating reflects up to 97% of thermal energy, and due to its good waterproofing properties it can be used for insulating rooms with high humidity - saunas, swimming pools;
Insulating the floor with polyethylene foam allows you to achieve good sound and heat insulation of concrete and wooden bases. The synthetic material has high microbiological resistance and chemical neutrality. It is produced in the form of a roll, the layer thickness can reach 15-30 mm;

NPE.

Polyethylene foam, made from a foam composition, has a cellular structure. Thanks to the air gap inside the coating, heat loss in the room is significantly reduced. The heat insulator is not subject to rotting, so it can be used to insulate floors in rooms with harsh microclimates. Insulation of the foundation from the outside Is it possible to insulate foundation walls? According to most experts, it is not only possible, but necessary, to insulate foundation walls. As the soil freezes, heat loss increases significantly, which contributes to an increase in heating costs in

winter period . How to properly insulate the floor outside the house? It is better to choose as a heat-insulating material
polystyrene foam boards
, since they are not afraid of frost and do not lose their thermal insulating properties when wet;
The slabs are secured outside the house along the perimeter of the entire foundation using dowels or frost-resistant glue;
It is desirable that the insulation is located several centimeters below the freezing level of the soil;

The thickness of the slabs must be at least 10 mm;

After fixing the polystyrene foam, it is advisable to sand the base part of the material and cover it with frost-resistant plaster.

Thermal insulation of the floor on the ground
As a rule, this technology is used to insulate floor coverings in private wooden mansions and bathhouses. During the work process, the following nuances should be taken into account:
The soil is thoroughly leveled and compacted;
After this, gravel and sand are laid as a substrate;
The thickness of the substrate must be at least 10 cm;
If it is necessary to lay hydrophobic heat-insulating materials, first perform waterproofing using roofing material; Then a thermal and vapor barrier is laid; At the final stage of insulation, the rough base is poured

cement mortar

This method of thermal insulation is no less effective than the previous one, but will cost much more. So, how to insulate a rough foundation along the joists?

The soil is leveled and compacted;
Along the perimeter they are laid out brick pillars under wooden logs in increments of 0.6 m;
Then on brickwork install the beams and spread the roofing material;
Light insulation (ecowool, mineral wool, granulated foam plastic) is poured into the sections between the joists;
Next, a layer of vapor-permeable insulation is laid;
At the final stage, a screed is made.

High-quality floor insulation can be done using organic, synthetic and foil thermal insulators. Each of them has special technical properties and application features that we described in this article.

One of the main conditions for comfort and coziness in the house is its insulation, including the presence of floor insulation. This is especially important when the floor of the home is in direct contact with the ground. Moreover, floor insulation is necessary not only as a means of improving living comfort, but also to reduce money spent on heating a home.

Basic materials for floor insulation

Today, thermal insulation materials are presented on the market in quite large quantities. Depending on the properties of the insulation, different requirements are imposed on them. The main ones, regardless of the type of material, are low thermal conductivity, high strength, moisture resistance and durability. The most common materials:

expanded polystyrene, most often in demand for insulating concrete floors;
extruded polystyrene foam Penoplex, another well-known brand is Technoplex;
expanded clay;
mineral wool;
cork insulation;
gypsum or fiberglass;
polyurethane foam;
cellulose, on its basis ecowool is made;
foam glass.

These insulation materials are divided into two types: natural and artificial. The first category includes cellulose and granulated slag, which is a by-product of iron smelting. Its use is quite popular due to its high thermal insulation properties. However, it may contain harmful impurities, so you should buy it only from trusted suppliers.

This is what bulk insulation looks like

All other insulation materials are of the artificial type. In my own way appearance they are also divided into several categories:

Sprayable. This is penoizol, or liquid foam, cellulose and polyurethane.
Rolled: mineral wool, linoleum, penofol.
Tile: glass wool, penoplex, polystyrene foam, foam glass, etc.
Bulk materials, which include foam glass, granulated slag, expanded clay and sawdust insulation.
Polymer mixtures, that is, self-leveling insulation materials.

Depending on what kind of insulation for a heated floor is used, the technology of its installation also depends. For example, linoleum, fiberboard sheets or cork insulation are rolled out on the floor and covered with hard material: parquet, laminate or wood covering. And mineral wool, expanded clay or extruded polystyrene foam need to be laid with a screed or joist.

Floor insulation with tile materials

Features of the most popular materials

Mineral wool and glass wool have good sound and thermal insulation properties I thank the presence of fine mineral fibers. When burning, harmful toxins are released, and noise is “extinguished.” The disadvantage of glass wool is that it quickly absorbs moisture, so it should not be used in damp rooms.

Most often, both of these materials are used for wooden floors due to their good vapor permeability. However, they still emit chemicals, although in small quantities, so glass and mineral wool cannot be classified as environmentally friendly materials. Their installation requires ventilation gap.

Cork insulation is more expensive due to its significantly best characteristics compared to other materials. It retains its strength and integrity for a long time, and it is also considered one of the most environmentally friendly and durable materials. Cork underlay can be placed under linoleum, which will significantly improve sound insulation. However, after some time, the unevenness of such a coating can be transferred to the linoleum, especially if you lay only one layer of material. This insulation is made from the bark of the cork oak tree.

A good replacement for glass wool is polystyrene foam. This is a moisture-resistant material, so it can be used in damp areas.

Expanded polystyrene reduces heat loss because it conducts heat poorly. It flares up with difficulty, however, if it catches fire, it’s a disaster, since fire resistance is not its quality.

Another name for expanded polystyrene, more familiar to all of us, is polystyrene foam. It is often used during the installation of a floating screed, after which it is filled with a concrete or cement layer. Due to its good moisture resistance, it can be used to insulate the floor on a balcony.

Due to the low density of glass wool, the material may slip during installation, which requires careful monitoring during installation Another affordable one- This is expanded clay. It is also used as floor insulation under screed, but mostly dry. Expanded clay is added to concrete or poured under gypsum fiber boards. It can also be used for a floating screed, but then you need to pour cement or concrete on top. Expanded clay has a porous structure, is made from clay, and serves as an excellent thermal insulation material even in very cold conditions. However, for this purpose, the insulation layer must be at least 10 - 15 cm.

The most important characteristics

Before choosing floor insulation, you should take into account not only its areas of application, but also important parameters that determine how much the material will retain heat in certain conditions:

Coefficient of thermal conductivity. Perhaps one of the most important parameters. It determines how much a material is capable of transmitting heat. Equals the amount of heat that passes through a material 1 meter thick with an area of 1 square meter in 1 hour. Calculations of this coefficient must be carried out under the condition that the temperature difference on both sides of the coating is 10 °C.
The characteristics of insulation largely depend on porosity. Equal to the ratio of the number of pores to the total volume of the material.
Ability to absorb water. The lower it is, the better material resistant to high humidity conditions.
Vapor permeability. It determines how well the material will “breathe”.
Strength. Important when there is a compression load.
Heat capacity. Determines how long a layer of material can withstand heat during temperature changes.
Fire resistance is the ability of insulation to withstand high temperatures.

First of all, it is necessary to consider what kind of floor – wooden on joists, concrete or a “warm floor” system. In all three cases you will need various materials

Floor insulation in a country house

Don't be surprised why you chose country house. They have both wooden and concrete floors, so a variety of insulation materials are installed.

Can be used to insulate wooden floors bulk materials, for example, expanded clay or wood concrete, as well as mineral fibers or glass wool. The mineral wool slab is covered with roofing felt or polyethylene, then filled with cement-sand or concrete screed. Foam plastic cannot be used due to poor vapor permeability. The thickness of the thermal insulation layer depends on the climate in a given region. If the average air temperature in winter is -20 °C, then this parameter should be 150 mm or higher.

To insulate the floor, level it and then lay the floor, it is necessary to fill in a loose gravel layer and compact it

To insulate wooden pores, it is best to lay logs every 60 cm. The gaps between them are covered with boards with lined insulation. It is necessary to lay waterproofing on both sides, the layer of which is 200 mm or higher. This insulation technology will protect the material from mechanical loads.

Foam plastic is suitable for a concrete floor, because it has good moisture resistance, compressive strength and a low thermal conductivity coefficient. The thickness of this insulation is at least 100 mm.

Thermal insulation should be laid tightly to the joists, leaving no gaps or cold bridges.

It is laid out as follows:

the concrete base is pre-dried and waterproofing is laid on it, which can be polyethylene film;
then they put polystyrene foam and lay the waterproofing layer again;
at the end a concrete screed with a thickness of at least 50 mm is poured.
Then you can start laying the flooring.

Waterproofing must be placed on both sides of the insulation

Video on laying floor insulation

Warm floor system

This is a so-called low-temperature water heating system used in apartments, kitchens, bathrooms and children's rooms. It is not installed very often, since this technology is quite expensive. Pipes with circulating water are laid under the floor surface hot water. Of course, in addition to pipes, it is necessary to purchase an automatic control device, manifolds, risers and shut-off valves.

Mainly for underfloor heating apply polymer pipes, which are made from polyethylene, polybutene and polypropylene. They are resistant to corrosion, durable, and have good strength.

There is another version of the “warm floor” system. A cable is laid under the flooring that converts current into heat. However, on top heating elements it is necessary to lay a concrete layer of 3–7 cm or cement-sand mortar, and only then lay the flooring. The disadvantage of this technology is that due to malfunctions it is necessary to completely dismantle the floor.

The advantages of low-temperature water heating systems are simplicity of design and low capital costs compared to steam heating systems

Main conclusions

It is impossible to say exactly which insulation is better for the floor. There are quite a lot of such materials today. Expanded polystyrene, or polystyrene foam, works well for concrete floors. Mineral wool and glass wool are more often used for wooden floors, but they must be well insulated so that dust does not enter the room when it wears out. Ecowool is also best used for wooden floors, but only where there is no moisture.

When choosing a coating, you should pay attention to its thermal conductivity, moisture resistance and other important characteristics.

When arranging floors, do not forget about their thermal insulation, which will prevent cold from seeping in from below, save heat in the room and distribute it evenly. When choosing floor insulation, you should take into account a number of points. In this article I will tell you what needs to be done to ensure that the insulator serves for a long time, fulfills its purpose efficiently and is in place.

Criteria for choosing floor insulation

Wrong choice of insulation is the main cause of heat loss through the floor surface. Therefore, I will first of all fill the gap in your knowledge about technical qualities And operational characteristics main types of heat insulators.

Things to consider

Before choosing a specific type of insulation material, consider:

what will be the operating conditions of the isolator;
condition and temperature of the soil base;
presence, as well as stability or frequency of groundwater levels;
the possibility of biological influences (damage to the heat insulator by rodents, the likelihood of the proliferation of harmful fungi);
Is the floor insulation compatible with the base material?

How to choose a heat insulator

Initially, you need to take into account the future construction of the floors: whether they are wooden on joists, concrete, or whether they will be equipped with underfloor heating.

For all these options you will need different kinds floor insulation.

Porous and loose material is suitable for insulating wooden floors, which does not hold its shape, as well as loose analogues. Such insulation, based on its structure, can be poured into the gaps between the joists or slabs, mats, or roll sections can be placed there.

It is extremely important that in this case the insulator “breathes”, allowing water vapor to pass through. Wooden floor coverings are installed precisely for this purpose - to allow the building to breathe.

Rigid thermal insulators are well suited for concrete floor cladding.. They hold their shape perfectly and are not subject to deformation from bending and compression loads. Such qualities are important when concrete mortar is laid on top of the insulation.

At this option vapor permeability of the material is not required. However, the insulator should not absorb water.

The "warm floor" system requires the same thermal insulators as for concrete covering . But with one condition. One side of the material should be foil-coated.

This layer will reflect into the room the heat that the warm floor will generate. Here you can use an insulator with aluminum foil or reflective film.

The material used to improve the thermal characteristics of the floor should ideally have the following qualities:

High level of durability, because the floor surface undergoes maximum mechanical loads.
Long service life. After all, floor coverings change very rarely.

The quality of insulation, such as excellent insulation characteristics, is very important. It will reduce heat loss to a minimum.
It’s good if the material is light in weight. So it will not exert strong pressure loads on bearing structures building.
The lower the level of water absorption the material has, the better.

In a wooden house, the vapor permeability of the insulation is important.
Sustainability thermal insulation material to fire no less significant.
The material must be environmentally friendly and safe.
The insulator must be easy to use. This has an impact on its costs and installation time.

Properties of insulating material

Before choosing floor covering insulation, pay attention to its most important technical characteristics:

Thermal conductivity coefficient. It indicates the ability of the insulator to pass thermal energy.
This parameter is equal to the volume of heat passing through a layer of material 100 centimeters thick and 1 square meter in area for one hour. This is subject to the condition that the temperature difference on both sides of the heat insulator is no more than 10˚.

Porosity. This the most important parameter determines the ratio of pore volume to the entire volume of insulation. It affects almost all other properties of the material.
Vapor permeability. This insulation indicator determines its ability to “breathe,” that is, to allow water vapor and air to pass through.

Water absorption. Indicates whether the material is moisture resistant or not. The smaller the parameter, the better. Insulation with a low level of water absorption can be used in damp rooms.
Strength. Important for its use where there are significant compressive or bending loads.
Biological resistance. It determines whether the material can resist harmful flora and fauna.

Fire resistance. It indicates the ability of insulation, without its destruction, to resist high temperatures for a certain period of time.
The fire safety characteristics of the material are associated with this parameter. These are its flammability, combustibility, level of smoke formation and degree of toxicity of combustion products.
Heat capacity. It affects the temperature resistance of the insulator. That is, its ability to retain heat during frequent temperature changes.
Density. It determines the specific gravity of the insulation.
Frost resistance. Indicates how many freeze/thaw cycles it can withstand.

Types of floor insulation

Now about what types of insulators there are based on the material of manufacture.

Mineral types of insulation are made from natural raw materials:

Mineral wool. There are several varieties of it: glass wool, basalt wool and slag wool. Essentially, these are fibers from rocks or industrial waste, pressed into rolls (mats) or slabs.

Bulk materials: granulated slag, foam glass, expanded clay (burnt and granulated clay).
Insulating concrete mixtures based on Portland cement with fillers and additives (perlite, expanded clay, vermiculite, sawdust, etc.).

Wood materials are used for arranging a substrate, dry screed or filling the gaps between lags:

Arbolit.
Cork backing.
Thick plywood.
Wood shavings and sawdust.
Cellulose eco-wool is used for thermal insulation of wooden floors. It can be blown out or simply poured out.

Polymer materials:

polystyrene foam in slabs;
extruded polystyrene foam in slabs;
reflective (foil) insulation in rolls and slabs;

liquid insulators having a foamed structure, for example, polyurethane foam;
ultra-thin insulation (thermal insulating paint).

When thinking about which insulation is best for the floor, pay attention to the technical characteristics of the material, as well as its operating conditions. The best solution is to use several types of insulation at various stages of floor installation.

So, for a concrete coating, expanded clay as a backfill and mineral wool on top of the rough screed are suitable.

Please note that polystyrene, extruded polystyrene foam and polyurethane foam release toxic gases when burned. They can kill a person in a few breaths. Therefore, I advise you to place them under a screed only where the insulator cannot come into contact with fire.

Now let's figure out what is the best thermal insulation for the floor, starting from its structure.

Insulation for underfloor heating systems

When deciding on a heat insulator for underfloor heating, keep in mind that it must have one feature - direct heat in a certain direction and prevent its leakage in unnecessary areas.

Reflective insulation

To reduce the cost of heating a room, I recommend that you choose foil insulation to work with heated floors. It will stop the cold from seeping down below. And also redirect the thermal energy coming from heating system into the room.

Our most popular brands of foil polyethylene foam are:

Penofol;
Izolon;
Energoflex;
Isoflex.

This insulation is produced in rolls. They have a width of 0.99-1.2 m and a thickness of 2-5 mm. Despite its thinness, this material perfectly solves the problem of thermal insulation.

Extruded polystyrene foam

This is one of the most durable, strong and waterproof heat insulators.

Its other advantages are below:

This insulation is produced in slabs. They are easy to cut into the required pieces, convenient for installation.
Expanded polystyrene has a dense structure, therefore it does not break or deform under loads.
Has a cellular structure. The pores of the material are filled with air and closed. Therefore, the insulator is not afraid of water - it does not absorb it and does not swell.
Resistant to chemically aggressive substances– alkalis, acids, alcohols.
Do not reproduce on the surface of the material harmful bacteria and fungi.
This insulation is not destroyed by atmospheric and environmental influences, does not react with most substances. Therefore it has a long service life.

Extruded polystyrene foam also has some disadvantages.

The material does not “breathe”", so it is better not to use it in conjunction with wooden floors.
This insulator is flammable. When ignited, it releases toxic gases.

However, in a heated floor system it is cut off from the environment by a screed. Thanks to this, you can safely use it.

The table below shows the cost of popular brands of this insulator.

Cork insulation

This material is made from the bark of the cork tree.

The advantages of this insulating substrate are as follows:

This insulator is natural and environmentally friendly.
The material does not rot, does not “sit down”, inert to chemicals, resistant to compressive and bending loads.

Cork is easy to cut with your own hands, so it’s easy to work with.
Life time This insulation can last up to 50 years.
Does not burn, but only smolders.
Withstands temperature up to +120˚.

This material is produced in slabs with a thickness of 2.5 and 5 cm.

Insulation for floors on joists

The logs for installing the floor covering are placed in increments of 0.5-1 m. The insulating material is placed on boards or boards on top of the logs. Or on boards nailed to the bottom or metal wire between the beams. Or it is poured into the space between the joists.

In this case, the floor insulation is carried out using mineral wool, bulk materials or polystyrene foam. To prevent the insulator from getting wet from water vapor, it must be covered with a vapor barrier film on top.

Stone, slag and glass wool

Mineral wool is now the most common insulation material; it is more in demand than polystyrene foam. There are two varieties of it: in slabs (more dense material) and rolls.

Mineral wool breathes, that is, it is vapor permeable. Therefore, it will be the best option for thermal insulation of a wooden floor indoors.

The advantages of the material are::

Relatively low price.
Versatility of use.
Easy to install.
Long service life - about 30 years.
Mineral wool not only has low thermal conductivity, but also has a high level of sound insulation and fire resistance.

Disadvantages: low level of moisture resistance of mineral wool.

Please note that when wet, this material loses most of its insulating properties. Therefore, when insulating floors with mineral wool, do not forget to hydro- and vapor-proof it.

Most often, slab types of insulation made from stone wool are used for thermal insulation of floors along joists:

Rockwool;
TechnoNIKOL;
Izover;
Tizol;
Linerock;
Knauf.

Or glass wool:

Tisma;
Izover;
Ursa.

Rolled cotton wool has one side of the mat covered with perforated paper. When laying insulation, this surface should be at the top.

The slab variety of mineral slab has one side that is more rigid and dense. It is marked with a blue stripe and should also be located on top. The table below shows the cost of popular brands of mineral wool.

Glass wool has similar characteristics to mineral wool. It is also not moisture resistant; in addition, it is quite weighty.

This floor insulation should be carefully insulated during installation. Otherwise, dust from the material, which has an irritating and allergic effect, will penetrate into the room.

Expanded clay

Porous round granules of expanded clay are obtained by firing heaving types of clay. During the production process, sawdust, peat and some other components are added to the raw materials. The quality of this bulk heat insulator for floors depends on the quality of the raw materials.

The cost of this insulation depends on the size of its granules. With increasing fractionality, the thermal conductivity of the material increases and its cost decreases. Expanded clay can be used both for floors along joists and under screed.

I give the cost of this heat insulator based on the size of its granules.

Insulation of floors with sawdust

This type of heat insulator is often used in wooden houses for floors along joists. Sawdust is not as effective as polystyrene foam or mineral wool. However, this is the cheapest and most environmentally friendly type of insulation. On average, a 50-liter bag of sawdust or shavings costs only 200 rubles.

The material is laid between the logs in bulk or nailed to the timber in the form of shields. In the latter case, pressed chips are used, i.e. chipboard sheets. The thickness of the insulating layer of sawdust should be at least 20 cm.

Eco-wool

This insulation is a loose material based on wood cellulose. All its characteristics coincide 80-90% with the qualities of wood. Eco-wool is foamed into the spaces between the joists.

Its advantages are:

The material is able to penetrate into the most inaccessible areas of the subfloor.
It forms a monolithic coating without “cold bridges”.
Eco-wool has high rates of heat and sound insulation.
It's easy to install.

There are also disadvantages:

Low moisture resistance.
To install eco-wool, you must use special equipment.
This material is flammable.

Insulators for floors under concrete or cement-sand screed

The photo shows expanded clay as an insulating backfill for concrete floors.

I recommend insulating concrete floors in several stages, because they are the coldest. Expanded clay would be an excellent option for insulating screeds on the ground. It can be used as bedding or used as a filler for concrete.

This material:

Stable to humidity and temperature changes.
Easy and thanks to this it does not heavily load the foundation.
Has a porous structure, therefore, in addition to excellent thermal insulation qualities, the floor is well soundproofed.
Natural, therefore environmentally friendly.

Basalt (stone) wool is a type of mineral wool. This durable and rigid material in slabs can also be used to insulate screeds.

This insulation is laid out on the base in a checkerboard pattern before pouring concrete. The layer of solution must have a thickness of at least 3 cm.

The instructions note that extruded polystyrene foam can also be used for thermal insulation of concrete floors.

Advantages of the material:

hard and durable;
does not deform from pressure loads;
easy to install;
moisture resistant;
has excellent thermal insulation qualities.

Of the minuses, I note:

flammability of polystyrene foam;
fear of ultraviolet radiation;
vapor tightness.

But when laying this insulation under the screed, all these disadvantages will not matter.

For thermal insulation of concrete floors, you can also use ordinary polystyrene foam. Most often, such floor insulation is used when pouring a floating screed.

Advantages:

Low cost.
Easy installation.
Good thermal insulation qualities.
Moisture resistance.

Minuses:

It's flammable.
Has poor sound insulation performance.
It lasts for a relatively short time - about 20 years.
Sheets of material are fragile.

Conclusion

Properly selected floor insulation will give you the opportunity to equip this surface with durable and high-quality thermal insulation. Suitable for a particular floor design different types insulators, which ones specifically, I described above.

The video in this article will give you even more food for thought. If you have any questions, ask them in the comments.