Strengthening insulation on a warm floor. Thermal insulation for a heated floor system: a comparative review of insulation materials. Doubts about choosing insulation

Nowadays, many people install them at home engineering systems in the form of warm floors. They replace the classic (radiator) heating method, as well as the use of convectors, heating panels, fan heaters, etc. as heat sources for heating rooms.

One of the varieties of such a system is heated floors. electric type. It is installed instead of the main heating system during the construction of private mansions, repair work in existing residential premises. Electric floors can also serve as an additional source of heat throughout the entire room or heat the necessary spaces (kitchen, bathrooms, children's room, etc.).

The use of warm electric floors in apartments and houses is currently not a given fashion trend, but a necessity that is caused by such factors:

creating comfortable conditions;
health care;
savings.

The essence of creating a floor for an electrical structure is to lay a special cable, electric heating mats or sections under the main floor covering. A huge advantage of such heating is that it can be carried out at will, and can also be programmed to turn on and off at certain times.

Warm electric floor is complex design, its performance depends on the correctly selected materials, components and devices, as well as the installation of all components in their place. Insulation is an important component of such a system. Properly selected for specific needs, it will direct and retain heat in the room and help save consumption electrical energy and household money.

It is a well-known fact from basic physics: warm air in a room tends to rise to the top, while at the same time it remains cold below. Such changes negatively affect a person’s well-being. You can get a cold and feel uncomfortable. Healthy body It will only happen when your feet are warm.

Installation of an electric heated floor promotes uniform heat distribution, proper heat exchange and the creation of the necessary microclimate in the room. The creation technology is simple, well developed by companies specializing in underfloor heating installation services. It is used for all types of premises. This type of floor is safe to use and does not require maintenance during system operation.

When creating an electric heated floor, you must adhere to 5 prerequisites:

it must occupy at least 70% of the area of the room in which it is installed;
when installing, you need to use a resistive one, preferably a two-core heating cable, always shielded, infrared film or special electrical mats;
high-quality insulation must be selected and laid correctly;
the screed must be made of sand-cement in compliance with the required proportions; it must be no more than 50 mm thick;
as a finishing floor covering after installation electrical system You can use ceramic tiles, natural and artificial stones, laminate, carpet, parquet and other materials that will match the installed electrical system.

Electric floor systems

Currently, there are cable, rod, liquid and film electric floor heating systems. Cable floors appeared in the 90s. A special shielded cable warms the floor surface up to set temperature. It is set on a thermostat, which responds to signals from a temperature sensor or a special external device that records the air temperature in the room. The heating cable can be mounted in special mats with a certain step, which speeds up the installation process of heated floors.

Warm electric floors of the rod type are made of coal heating elements. They are connected by conductors and form a grid. Each carbon element is a separately functioning device. This is very important - if one of them fails, the rest will work.

The electric fluid system is polyethylene pipes of a certain diameter, filled with a heat-conducting liquid, inside of which there is a heating core. The pipes at their ends have a connecting coupling on one side and a damper device on the other. The latter compensates for the expansion of the non-freezing liquid. Such a system is connected to the power supply using a special regulator.

A polymer film is a product with heating elements applied to it, emitting heat in the long-wave range. Film thickness – no more than 3 mm, width – 0.5÷1 m; it has, depending on the production technology, different heat transfer.

Polymer film is not used for laying under tiles.

Thermal insulation requirements

Why is thermal insulation (also called insulation) needed when installing heated electric floors? During the operation of such a floor, heat losses occur, which are associated with heating of the cable/mat/film and the floor. Laying a special material called thermal insulation will help to avoid heat loss. It will be the basis on which the components of the heated floor are mounted.

In the retail chain, materials with thermal insulation properties are presented in a large assortment; buying them is not difficult. They are made from different components in the form of rolls, panels, films and membranes. Not all materials are suitable for creating electric heated floors. The requirements for thermal insulation material for electric heated floors are as follows:

must have a low thermal conductivity coefficient;
have resistance to elevated temperatures;
easy to install and not deform during operation;
should level out minor unevenness in the base;
must withstand heavy loads;
have soundproofing properties;
withstand aggressive environments;
have a high degree of strength;
do not absorb moisture;
be electrically safe;
be made from environmentally friendly materials (should not release toxic substances into the environment);
have long term operation.

Main types of thermal insulation

Thermal insulating materials for installing electric heated floors are made from natural and synthetic raw materials. From a large assortment, we can highlight the thermal insulation materials presented below.

Natural thermal insulation is made using a special technology from cork oak bark and is therefore called cork. Such insulation is supplied to the retail chain in the form of rolls 10 m long and 1 m wide. Thickness ranges from 1 to 10 mm. During installation there is no need to glue it, it is easy to install, has excellent sound and heat insulation properties, and can have a rubberized base, which eliminates the need for additional waterproofing.

Installation must be carried out using heat-reflecting material, because The design does not have the required component of an electric floor, which allows heat to be reflected to the floor surface.

Modern thermal insulation materials of artificial origin for electric floors include the following products:

"Penotherm". It is made of porous polypropylene, has a cellular structure, without and with markings. The latter makes the installation process easier. Aluminum foil serves as a heat-reflecting layer. Depending on the quality of installation, it can increase thermal efficiency by up to 70%. The insulation is supplied to the retail chain with a width of 1200 mm and a length of 10 and 30 m, of various thicknesses.

"Penofol". Made from foamed polyethylene. It has a foil layer with a thickness of 100 microns. Available in four types, differing in surfaces. "Penofol" type A has a foil surface on one side, type B has a foil surface on both sides, type C has one side with foil and the other has an adhesive layer, type ALP also has a foil side and is located on the other polyethylene film. Rolls have a thickness of 3÷10 mm and a length of 10÷30.

"Folgoizolon". It is made of foamed polyethylene and has air bubbles in its design, as well as a foil layer. Available in two modifications: cross-linked (PPE) and non-cross-linked (NPE) polyethylene foam, differing in service life. For products made from cross-linked polyethylene it is much higher. Thanks to the material with high technical characteristics, it retains heat well. Supplied with or without underfloor heating markings in sheets rolled into rolls of various thicknesses and lengths. It is an ideal heat-insulating material for installing heated floors on balconies, loggias and other cold rooms.

The foil layer must be laminated.

Additional insulation can be a polyethylene laminated film with markings for underfloor heating. Products with a thickness of 3 or 5 mm, a width of 1 m and a length of 10 to 30 m are used.

Installation features

Properly selected material for thermal insulation not only makes staying in the room comfortable, but also reduces electrical energy consumption. The technology for making electric heated floors depends on it.

All work on arranging an electric heated floor comes down to the following operations:

preparation of the base;
installation of thermal insulation;
installation of heating cable/mats/film;
performing a screed;
installation of finishing floor covering.

At the base preparation stage, it is necessary to dismantle the old screed, level the surface as much as possible (differences should not exceed 10 mm) and clean it from dirt and dust. If necessary, the base surface must be waterproofed.

Before you begin laying thermal insulation for an electric heated floor, you need to decide on its thickness. It has been experimentally established that above unheated rooms it should be 50÷100 mm, and for interfloor ceilings– 20÷30 mm. Seams and joints of thermal insulation must be taped with special tape (foil), between the wall and the screed - with damper tape. When laying several thermal circuits with different temperatures To separate them, a T-shaped damper profile is used.

Thermal insulation material is not only laid on the base of the floor, it must be laid along the perimeter of the wall to a height of up to 20 mm.

Installation of electric heating elements must be carried out taking into account the characteristics of the installed system (single- or two-core cables, mats, UV films).

It is better to screed the floor using a sand-cement mortar with the addition of special plasticizers that will prevent cracking. Its thickness should be at least 3 cm. After drying, begin laying the finishing floor covering. It can be tiles, parquet, linoleum or another type. They are installed taking into account the manufacturer's recommendations.

Video

A thermal insulation layer under a warm electric floor is not a luxury, but a necessity. It will help to evenly distribute the heat from the heating elements, retain it and direct it in the required direction. Poorly performed installation at any stage of creating electric heated floors will entail negative consequences. This will affect comfort, increased energy consumption and, as a result, unnecessary waste of money.

Installation of heated floors is not a particularly difficult task and is carried out using strictly regulated technology, using one or another material that performs certain functions.

Insulation for a warm water floor plays the role of a thermal insulation barrier, which directly affects the efficiency of the system.

Features of thermal insulation of heated floors

The structure or “pie” of a heated floor can consist of various functional layers. The standard version is considered to include the following type of scheme: rough base, layer thermal insulation material, reinforcing mesh, heating elements, layer concrete screed And finishing coat.

IN general view, this scheme is applicable both for hydraulic or water systems, and for warm electric floors. That is, in both cases, the rough foundation is prepared and the insulation is laid.

Insulation when used together with warm floors will play the role of a heat-insulating and heat-reflecting barrier. The main function of this layer is to prevent heat loss through the supporting base and redirect heat flows in the opposite direction.

Thermal insulation helps reduce overall heat loss through the load-bearing floor

In the absence of a thermal insulation layer, severe losses of thermal energy are possible, which will necessarily affect a constant decrease in the temperature of the coolant and heating elements. A decrease in temperature, in turn, will lead to increased energy consumption for heating the coolant and increased costs for maintaining the “warm floor” system as a whole.

Types of insulation and their features

Insulation under water or electric heated floors is not much different from traditional thermal insulation materials used for insulation load-bearing elements building, inner surface walls, etc.

Thermal insulation materials for use with heated floors

The most commonly used types of material are:

mineral wool– an affordable and time-tested material, characterized by simple installation technology, good heat-insulating and sound-absorbing qualities, high service life and environmental friendliness;
expanded polystyrene - a modern heat insulator with high heat saving, durability, low water absorption, resistance to aggressive biological environments and the action of certain chemicals;
cork coverings are a material made from natural ingredients (cork oak bark). It has a small thickness while maintaining high thermal insulation qualities. Does not rot, is not susceptible to the formation of mold and mildew. Eco-friendly and safe for humans;
heat-insulating mats – special ones with a rubberized waterproofing surface. They have protruding clamps or so-called “boss”, which facilitate the process of laying heating elements.

This or that type of insulation, in addition to its advantages and practical qualities, has a number of disadvantages. Mineral wool may contain phenol and other harmful substances, which can be released when heated, which is especially critical when installing heated floors.

Reflective surface helps reflect thermal energy

Exist different kinds mineral wool and without the content of phenolic compounds, but upon purchase this fact should be further clarified. You can request to present a quality certificate or other document confirming that such substances were not used in production.

Significant disadvantages of expanded polystyrene include the thickness that the material creates after it is laid. So the minimum recommended layer of polystyrene foam should be at least 5 cm. Considering that in addition to 5 cm of insulation, 5-8 cm of concrete screed will be poured, this will significantly affect and raise the floor level.

The same fact can be attributed to polystyrene foam mats, but as practice shows, in modern private houses the ceiling height is at the level of 2.7-3 m, which can guarantee that this indicator will not be greatly affected or reduced.

In apartments, especially for buildings with low ceiling, it is recommended to use insulation based on polyethylene foam. The thickness of this coating is 5-10 mm. This is quite enough for effective removal and redirection of thermal energy.

What type of insulation is most effective?

The choice of the appropriate type of insulation should be based on a number of factors. The simplest way to select is to take into account conditions such as climate zone, temperature in winter time year, desired room temperature, type of building, floor and material characteristics.

For example, for the first floor of a house made of aerated concrete, lined sand-lime brick and located in the North-West region, where winter temperatures rarely drop below -20-25 °C, you can use a 5 cm layer of polystyrene foam. For heated floors installed on the second and subsequent floors, foamed polyethylene with a reflective surface will be sufficient.

For buildings located in conditions where winter temperatures drop to -30 °C or more, it is recommended not to skimp and lay a 10th layer of polystyrene foam with mandatory insulation load-bearing walls, and windows.

Heating temperature (top) and cooling rate (bottom) of the surface, where green is thermal insulation with a reflective side

For apartments in standard apartment buildings, especially for rooms located on 2 or more floors, you can limit yourself to laying a substrate made of foamed polyethylene or a coating with a reflective surface. In such cases, high-quality installation of double-glazed windows will play a big role, since heat loss through ordinary wooden frames too high.

Additionally, it is worth clarifying about polyethylene foam with a lavsan or metallized surface. There is an opinion and arguments that foil insulation, used as “know-how” and recommended for joint installation with heated floors, is ineffective.

Comparison of heating using polystyrene foam (blue) / polyethylene foam (green)

This is partly true, but only when the technology for performing the work is not followed or low-quality material is used. For the device under the screed, only polyethylene foam with a lavsan surface (NPE-L) should be used, since the alkaline environment of the solution can damage the metallized layer represented by aluminum foil (NPE-F).

The thickness of the screed over the deformable insulation, which is NPE-L, must be at least 60 mm. The recommended concrete layer is 80-100 mm. This is due to the fact that the use of deformable insulation increases the risk of cracks forming during the hydration of the concrete layer.

To prove the effectiveness of such coatings, we can cite the graphs obtained during the experiment, which you can see just above.

General laying and installation technology

Laying insulation for a warm water floor is carried out after a series of preparatory measures. These usually include: dismantling old flooring and existing system floors, removing construction debris and cleaning the surface from dust, eliminating possible surface defects and preparing the base for laying the heat insulator.

An expansion tape must be installed along the lower edge of the wall.

Dismantling of old floor finishing is carried out taking into account the material used. To remove the tiles you will have to resort to power tools. Removing laminate or plank flooring can be done using available tools.

The resulting construction waste is collected in tight bags and taken to a landfill. Next, a visual inspection is carried out concrete slab or supporting base for damage. If they are present, the existing defect is repaired and grouted using building mixtures: cement-sand mortar, special putty and filler.

If oil stains or paint are found, it is advisable to wipe them off using ordinary alcohol solvents. If the surface has a strong slope or contains a large number of potholes, then a self-leveling mixture with a thickness of 2-3 mm should be poured.

To fix the heating elements, a reinforcing mesh is placed on the insulation

To level out thermal expansion, a damper tape is installed at the bottom of the wall. The tape is fixed around the perimeter of the room at a height of 15-20 cm. After the solution has hardened, excess material can be cut off.

A polyethylene film is spread over the surface of the base and overlaps the walls. It is desirable that the density of the material be more than 150 g/m2. Insulation is laid on the film. If necessary, the material is trimmed and joined using the butt-to-butt method.

For polyethylene foam, you can use special tape with a laminated surface, which is used to glue the joints. Next, a reinforcing mesh is laid on the insulation, to which the heating elements are attached.

Further work requires more detailed consideration. IN general case, the installation of the heat insulator occurs in a similar sequence, with the only difference being that the material itself and its thickness change.

Installing heated floors is expensive. Equipment, pipes, installation services - all this is money. The cost of insulation for a warm water floor is only about 3% of all costs, but it is with its help that heat loss can be reduced by up to 20%.

What types of thermal insulation materials are at the peak of popularity? What are their advantages and disadvantages? Let's try to figure it out.

Penofol is foamed polyethylene covered with foil on one or both sides. The heat-reflecting effect is achieved due to, figuratively speaking, captured air bubbles, as well as a layer of aluminum foil.

Advantages of penofol:

small thickness, only 2 – 10 mm;
withstands temperature changes from -60°C to +100°C;
insulates well from noise, moisture and steam;
low price - only about 0.1 USD for 1m².

However, it also has a drawback. Aluminum is destroyed if it comes into contact with cement, and this is the main component of the floor screed. Therefore, over time, it will cease to fulfill its main purpose - to reflect heat.

Demand dictates supply, so the buyer can be offered a sheet of laminated polyethylene foam with a foil surface. Lamination reliably protects aluminum from destruction.

Expert advice: if the choice still falls on penofol, cover it additionally plastic film. The canvases need to be overlapped and the joint should be sealed with tape or masking tape. Then the foil will be protected from the aggressive effects of the cement-sand screed.

Expanded polystyrene

Expanded polystyrene is a more accurate name for polystyrene foam. These are compressed granules that are 98% air. It has low density and, therefore, lightness. What are the advantages of polystyrene foam as floor insulation?

Ease of processing.
Resistant to water, mineral oils, acids and alkalis.
Does not rot, is not affected by bacteria.
High thermal insulation performance. 30mm thick foam will retain as much heat as reinforced concrete slab thicker than 1 meter.

But foam plastic also has disadvantages:

Permissible flooring height. It is not always possible to raise the floors by 7–8 cm. In this case, penofol with its small thickness will be a good compromise option.
Insulation as part of a water floor system from a specific manufacturer. OEMs and Supplies may provide a guarantee efficient work their products only if insulation of the same brand is used.

Thus, prudence will prompt you to weigh and take into account not only the thermal effect during floor installation work, but also whether the insulation characteristics will be maintained in the future. And of course, you shouldn’t write off how the finished floor will look in combination with the rest of the interior finishing elements.

How to thermally insulate a warm water floor with your own hands, watch the video:

Insulation for heated floors contributes to a more uniform distribution of heat inside the room. A material with specific properties (thermal insulation) is an important component of the heated base pie.

In the absence of such a layer, the water heating system functions less efficiently and is not durable in operation.

The feasibility of thermal insulation

Any heated floor, as well as a water version, must be equipped with insulating materials that are characterized by low thermal conductivity.

Problems that thermal insulation solves:

Uniform distribution of thermal energy throughout the room, which is important given the configuration of the heating system: the water floor consists of straight/curved sections of pipes, which means the floor will release heat unevenly;
Insulation of communications below reduces the intensity of the outflow of thermal energy outside the room through the ceiling.

In addition, the thermal insulation of the “warm floor” system helps to simplify the installation of the heating structure. But this applies to the option with bosses, since in this case the laying and fastening of pipes is faster.

The principle of choosing thermal insulation material

Considering that insulation is carried out inside the “pie” of the water floor, the material must be as effective and safe as possible, both in composition and when operating conditions change (breakage of the tightness of communications, the formation of fungus, fire hazardous situations, etc.).

Thermal conductivity table of insulation: Foil insulation, mineral wool and polystyrene foam are most often used.

Accordingly, thermal insulation is selected from a number of options based on the following properties: low thermal conductivity, fire resistance; insulation with sound reflecting ability is additionally considered. Another important quality is moisture resistance. Different types materials are characterized various properties, which means you need to study their features before purchasing.

Laying and selection of polystyrene foam

Release form: sheets/plates, which simplifies the installation of a water floor. The dimensions of the material differ significantly. The main characteristic of any insulation is thickness. In the case of expanded polystyrene, the value of this parameter varies from 30 to 120 mm. A common type of this insulation is penoplex. It is produced by polystyrene extrusion.

Expanded polystyrene should be securely hidden under a cement layer or other reliable covering

The colder the room under the ceiling, the greater the thickness of the thermal insulation should be. The main disadvantage characterizing penoplex is its low strength. For this reason, at the stage of arranging a water floor, reinforcement of the “pie” of the heating system is often performed. There is an analogue with simpler properties - polystyrene foam. But it is used less frequently due to the availability of more suitable materials.

The thickness of thermal insulation made of polystyrene foam or expanded polystyrene 100 mm, for warm regions or second floors, can be reduced by 30%.

Features of using mineral wool

To install a water floor, insulation with a fairly high rigidity is used. For this reason, they are usually used mineral mats. Their main advantage is the ability to fill free space due to elasticity. However, this type of material is not resistant to moisture.

If mineral mats absorb enough water, they will lose their thermal insulation properties. But if, when installing a water floor, you provide effective waterproofing to this layer of the “pie,” then the quality of the insulation will not suffer. It is allowed to use basalt and fiberglass types of material.

Types of cork material

This type of thermal insulation is also susceptible to moisture, and in addition, it is not resistant to the formation of fungus. However, cork is characterized by a fairly good ability to reduce the intensity of heat loss.

When installing a water floor, cork material with a wax coating is usually used. But, if you compare penoplex or even its less effective analogue polystyrene foam, cork is somewhat inferior in terms of heat saving.

Profile mats

This is a special material equipped with bosses and a vapor barrier layer. This configuration allows not only to provide heat and vapor barrier to the floor, but also to securely and quickly fix the pipes without the need for special fasteners.

Substrates and mats must be universal and easy to install.

Features of insulation installation

If there is cold ground under the floor or an unheated basement, it is recommended to use insulation thick enough to ensure the effective functioning of the heating system (100 mm, 120 mm). For cases where there is under the floor warm room, insulation, the thickness of which is 30-50 mm, is quite enough.

Properly carried out waterproofing of the base surface solves problems associated with the release of phenol and high humidity.

Depending on the type of material from which the rough base is made, as well as on the type of insulation, the method of attaching the mats/slabs is determined. Penoplex is usually fixed with an adhesive. In this case, it is recommended to use slabs as large as possible, because it is desirable to avoid the formation large quantity leaks. This will lead to the fact that penoplex will lose its thermal insulation qualities due to the appearance of “cold bridges”.

Step-by-step instruction laying mats and thermal insulation

It is recommended to lay mineral wool materials between the joists. In this situation, it is enough to use mats slightly larger in width than the distance between the beams of the log system. But the difference in size should not be too large, as this will lead to deformation of the insulation, and at the same time the thermal insulation qualities will deteriorate.

A lining is placed on top of the thermal insulation layer; it is preferable to choose a material foiled on one side for this purpose, but not aluminum foil. A communications system is laid on top.

If a mineral wool material has been chosen, a layer of waterproofing must be secured from below, before the log system is installed. This will ensure additional protection from moisture. The joints and connections of the moisture-resistant film are secured with tape. In the case when penoplex is installed, all connecting seams between the plates must be filled with sealant.

What are the consequences of lack of thermal insulation or its insufficient thickness?

In such cases, there is a significant decrease in the efficiency of the heating system. This means that due to significant heat loss, the room will not warm up, and the cost of heating the coolant will not decrease.

In turn, a cold microclimate in a living space will lead to the formation of mold on surfaces, pieces of furniture and even on things. This is due to increased humidity along with insufficient high temperature air in the room. And with temperature changes, condensation forms, which has a detrimental effect on any systems and mechanisms.

In accordance with the technology for installing a heated floor, its “pie” must necessarily contain a heat insulator with low level thermal conductivity. And the water design is no exception.

Today, manufacturers offer a wide variety of thermal insulation substrates, and it is difficult for a person not versed in construction to choose insulation that meets all the requirements.

Is thermal insulation necessary for underfloor heating or not?

Thermal insulation in the “pie” of a warm water floor plays a huge role; the correct functioning of the entire heating system depends on it. The screed, poured over the thermal insulation, turns into a large surface that transfers heat.

The main functions that a thermal insulation flooring under a warm water floor should perform:

distribute heat flows evenly throughout the heated room, this is especially important when laying a water structure, since the configuration of this system consists of straight and curved pipes, so the heat is not distributed evenly;
prevent the outflow of warm air through the ceilings; it serves as a reflective screen, which also makes it possible to save thermal resources;
act as sound insulation;
prevent the entry of moisture and cold from below - when arranging a structure above an unheated room or on the ground;
prevent the formation of moldy and fungal deposits.

In addition, by using polystyrene foam mats with bosses as insulation under a warm water floor, you significantly simplify the process of installing and fixing pipes.

For your information! If the thermal insulation layer is correctly selected and laid, the floor “pie” turns into a closed thermal device, where thermal radiation is distributed evenly and in the desired direction.

Types of insulation for water heated floors

When selecting a material for a thermal insulator for a warm hydrofloor, you should take into account the characteristics and technical indicators of the room, as well as the base on which the substrate will be installed.

For the most part, the thermal insulation material has the same degree of thermal conductivity. But the thickness of the layer is often required even in the same room.

The most common types of thermal insulation used under water-heated floors include: mineral wool, cork, expanded polystyrene, profile mats. This material has different thermal insulation characteristics and properties, and this should be taken into account when choosing and installing the floor.

Let's take a closer look at each type of material for thermal insulation of a heating structure.

Cork backing

Cork is an expensive product because it is made from oak bark. Available in rolls or sheets, but technical specifications there are no differences. The only difference is the size and thickness.

Cork backing:

has low thermal conductivity;
waterproof;
environmentally friendly;
hypoallergenic;
elastic;
light-resistant;
fireproof;
resistant to sudden temperature changes;
not susceptible to chemical influences.

Cork product - perfect option for the “water heated floor” system, and if funds allow, then it is better to choose it. The thickness of this substrate contributes to effective saving of heat resources, which is especially important when installed on the ground.

Cork is not subject to deformation and shrinkage when pouring concrete screeds. It cannot be harmed by insects and rodents, mold and mildew, and is also not terrible.

However, it should be noted that the use of cork as a substrate will affect the height of the ceilings, and additional reflective material will also need to be purchased.

Expanded polystyrene

Expanded polystyrene is the most common type of thermal insulation under water heating floors, and has a fairly affordable price. It provides high-quality protection from water and steam, a high degree of sound insulation, does not deform from exposure to temperature, and does not react to chemical substances and resists the formation of mold and mildew.

Thermal insulation consists of many bubbles placed in a shell. To add strength to the structure with this substrate, a reinforcing mesh is used. Ease of installation, which even an inexperienced person can handle, also plays an important role in its popularity. In addition, the service life is several decades.

The main disadvantage of polystyrene foam is a fire hazard, so it must be insulated with a foil backing.

Expanded polystyrene comes in several types, which differ in production technology and properties:

Extruded polystyrene foam is durable and better performs its main function - thermal insulation. It has increased strength, since the particles are tightly bonded to each other. But the vapor permeability indicator is almost zero. Its thickness is at least 3 cm. The slabs are often colored.

Foamed - it is also called polystyrene foam. Has a small specific gravity and a high degree of vapor permeability. It is not recommended for foundation insulation, as it is destroyed by moisture. The color is usually white. It is produced in a non-extruded way, that is, the structure has cells with air channels.

Penoplex - its cost is not high. It has good performance in terms of reflecting heat flows, therefore it is considered one of the best insulation materials. During installation, a waterproofing substrate is not required, and the process itself is not complicated; it is easy to do the installation yourself. Available in slabs of various sizes, the thickness of which ranges from 20 to 100 mm. The package contains from 4 to 20 sheets - it depends on the thickness of the product.

Main advantages:

high heat and vapor insulation;
1. absence of emissions containing harmful substances;
2. resistance to the effects of microorganisms;
3. does not allow moisture to pass through;
4. has high strength.

Profile mats - they are also based on polystyrene foam. They are stamped using a special technological method and covered with a film for waterproofing. The slabs are high-strength products that can withstand mechanical loads. They are equipped with protrusions; water heated floor pipes are laid in them, which facilitates the process of placing the circuit. They have side locks - this simplifies installation and minimizes the presence of seams. The model is considered the most profitable, in terms of financial investments, when constructing heating.

Mineral wool

Mineral wool is fireproof, unlike polystyrene foam insulation, but its price is more expensive. It is manufactured in slabs, making it easy to install.

When installed on an aluminum underfloor heating base, this insulation has high efficiency, even when placed on the ground. In addition, it has good noise and heat insulation, increased rigidity, and is resistant to chemicals.

The main disadvantage of the product is that it contains carcinogenic and toxic substances that are dangerous to human health. In addition, cotton wool is hygroscopic and vapor-permeable, and when laying it in a screed, care must be taken to protect it from moisture and steam emissions.

Rolled thermal insulation made of foamed polyethylene

Foamed polyethylene (penofol) is gaining popularity today. It is sold in rolls and has a thickness from 3 to 10 mm. The product is equipped with a foil surface, it reflects heat and allows you to significantly reduce the thickness of the “pie”, since there is no need to lay additional waterproofing made of lavsan or thermal insulation.

There are the following types:

A - one side has a layer of foil;
B - foil on both sides;
C (self-adhesive) - there is foil on one side, glue is applied on the other;
“ALP” - one side is foil, the other with a special film.

Each type is suitable for use under heated floors, and almost completely copes with the thermal insulation of the device.

The technical indicators of foamed polyethylene and polystyrene are largely similar, the thermal conductivity coefficient ranges from 0.037 - 0.049 W/m °C.

It is worth mentioning the ability of the material to absorb water, which results in a decrease in its thermal insulation properties.

In addition, under the influence of a wet screed containing chemicals, the aluminum foil layer becomes unusable. To combat this problem, manufacturers began to produce the product in sheets with a film-like coating on top of the foil.

Metallized lavsan film is capable of qualitatively protecting the screed and flooring from the effects of alkali. Insulation with an aluminum layer without a thermally resistant coating is not used. The positive side of the product is its high degree of heat reflection.

Important! When laying, the foil side of the product should face up.

Which insulation to choose?

As mentioned above, a warm water floor requires insulation, since without it it will not function effectively. In addition, if there is thermal insulation, the system is more economical. It is important not only to know how to properly insulate a heated floor, but also how to choose a suitable heat-reflecting material.

When purchasing thermal insulation, you need to look not only at the characteristics, heat-saving properties of the material and its parameters, but also at its service life. Since a number of products with good performance often have a short service life.

Therefore, there will be a need to replace it before maintenance of the system itself is required. This is especially important in rooms with tile flooring, because it is difficult to dismantle it. In this regard, experts advise purchasing a product with a warranty period of 10 - 15 years.

level of thermal conductivity;
density indicator;
hydro and vapor tightness.

For rooms with high ceilings, it is better to choose durable, rigid types that have a polymer base. If you insulate - great option mineral wool, because it is fireproof.

For your information! You should not save excessively on thermal insulation material when laying a heated floor. Its cost will pay off within 3 years, especially when heating with natural gas.

Features of laying insulation

The principle of installing a thermal insulation layer is simple, no special tools or special experience are needed, the main thing is to follow the technological process.

Watch the video on how to choose insulation:

Installation of polystyrene foam boards

Installation work polystyrene foam boards under a water heated floor looks like this:

Regardless of the type of thermal insulation product, you need to start by preparing the subfloor. It should be smooth, without cracks. If irregularities and flaws are found in the surface, they need to be repaired.

Waterproofing measures consist of arranging a layer that protects against moisture, this can be a polyethylene film.

Sticking damper tape around the perimeter of the room is necessary to compensate for temperature fluctuations.

Laying insulation boards over the entire area - the sheets are fixed to the base using plastic staples or dowels; the product can be attached to glue.

Spreading foil film and installing reinforcing mesh over the insulation.

Installation of heating elements (pipes) - they are attached to the grid according to the planned scheme. The seams between the plates should be taped with tape, this will help retain heat.

Pouring concrete screed over the pipeline. To ensure surface strength, it is recommended to add plasticizers to the solution. It is necessary to let the mixture harden, this will take about a month.

The last stage is the installation of the finishing coating.

For your information! It is worth considering that underfloor heating pipes with the coolant inside have significant weight, plus the screed and finishing coating, all of this together will push through the insulation over time.

To avoid this, high-strength thermal insulation is required. In addition, to strengthen the structure and distribute the load evenly, it is recommended to reinforce or lay polystyrene foam slabs with bosses. In addition, such mats facilitate the process of placing pipes and fixing them.

Laying rolled polyethylene foam

Installation work on the construction of a water-heated floor using rolled polyethylene as insulation begins with leveling and cleaning the base.

At the second stage, the heat-insulating material is prepared. This consists of cutting the heat insulator into strips required length, using a stationery knife.

Next, the foil product is placed on the prepared base with the metallized surface facing up to ensure the best reflection of heat. The canvas should extend onto the walls, this is necessary to compensate for the expansion of the screed when heated. The insulation is attached to the floor using glue or double-sided tape. And the seams should be taped using single-sided tape.

The process of installing a water circuit on polyethylene rolls is facilitated by the presence of a printed installation markings, which shows the distance between pipes. Heating elements on penofol can be placed in a “snail” or “snake” pattern.

Further work on the construction of water heating floors involves installation reinforcing mesh, pouring concrete screed and laying flooring.

For your information! For use in water warm device Penofol brand ALP is recommended.

Laying mineral wool

Mineral wool cannot be crushed, so the most the best way its installation is on the floor, with the installation of logs.

Step by step, the installation of the “pie” of a warm system with a thermal insulation substrate made of mineral wool is as follows:

Preparation of the base is a mandatory stage of work when installing any heated floors. If the floors in the house are old, it is better to completely remove them before concrete floor or rough wooden floor. The surface must be inspected for irregularities and cracks; if any are found, they are repaired.

Laying hydro- and vapor barrier substrate -necessary stage using mineral insulation, because he is afraid of moisture. For these purposes, roll-type waterproofing is suitable - roofing material, or others. modern materials. The sheets are fixed to the base using polymer or bitumen mastic. The material is laid in an overlap, the seams should be coated with mastic.

Arrangement wooden logs- they are attached to the subfloor over the entire area. Blocks measuring 5 by 6 cm are taken and installed on concrete surface, fixed with dowels, and on a wooden floor with self-tapping screws. The pitch between the fasteners depends on the flooring that is planned to be laid; it ranges from 40 to 80 cm. It requires making cuts in the joists to rotate the contour.

Important! If mineral wool is used as insulation, then the distance between the logs should exceed the width of the material by 1.5 - 2 cm.

Laying insulation - mineral wool is installed in the spaces between the bars. It is necessary that it sinks at least 5 cm, as a ventilation gap is required.

Installing a second waterproofing layer is necessary, because cotton wool is not moisture resistant. An ordinary polyethylene film is used, which is placed in a stretch on the logs and fixed with a stapler.
Preparing the substrate for pipes - slats are used that are nailed across the logs, with a distance of 30 cm from the walls. There should be grooves between the slats in which a metal profile for laying pipes will be placed. Their size depends on the step of laying the contour.

For your information! Metallic profile can be replaced with foil in which the pipe is wrapped.

Installation of the heating circuit - heating pipes are laid into the installed profile according to the planned layout.

Installation of flooring for interior covering - this can be chipboard or plywood.
Finally, the floor covering is laid.

At this point, the warm floor with a thermal insulation backing - mineral wool, is ready for use.

Optimal insulation thickness

It is important to make the right choice not only of the insulation model, but also of its thickness; thermal energy savings depend on this.

For your information! If the thickness of the insulation is small, then it goes under the floor most of heat, its quantity is equal to the flow warm air rising up.

The thickness of the insulation should be selected depending on climatic conditions. It is clear that in areas with a cold climate, the layer of thermal insulation material should be larger.

The type of room located under the warm water floor also plays an important role. If it's cold basement, or the structure is laid on the ground, then the insulation layer should be made thicker, 100 - 120 mm. When constructing a heating floor over a heated room, a sufficient thickness of 30 - 50 mm.

Installing a thermal insulation layer under a heated water floor is not a luxury, but a necessity. Incorrectly done insulation will lead to deterioration in the quality of heating and unnecessary costs.