Insulation for creating a warm water floor allows you to save energy resources. They reduce heat loss by 15-20%. Their main task is to prevent radiant energy from penetrating into the ground, lower rooms or basement.
In the overall system, insulation for a heated floor performs several functions. It prevents unnecessary heat loss and ensures uniform heat distribution. In addition, any material becomes an additional noise barrier.
When viewing your options, it is important to consider the key features of heated floor insulation:
- low thermal conductivity coefficient;
- resistance to dynamic and static loads that will arise during operation;
- shape stability;
- long service life.
In addition, thermal insulation for heated floors must be fire-resistant and safe.
Manufacturers offer a wide range of insulation materials that differ in structure, thickness and characteristics. When choosing, you should take into account the characteristics of the room where the heated floor system is being installed, a possible increase in the height of the structure, and thermal insulation characteristics.
Popular materials
Expanded polystyrene. Foamed polymer material. It is distinguished by good thermal performance, light weight and affordable price. The slabs do not rot and do not allow moisture to pass through. The disadvantage of polystyrene foam is its relatively low sound insulation performance.
Leading manufacturers offer special insulation for underfloor heating with bosses. Thanks to special protrusions, laying water floor pipes is not difficult. The material has increased strength characteristics and is protected from condensation. Foil mats are also available for sale.
Foil-coated mineral wool. Insulation for water heated floors is offered in the form of rolls or dense slabs. It is made from natural raw materials and belongs to the class of non-combustible materials. Particularly popular are basalt mats, which are characterized by high dimensional stability. When working with them, a minimal amount of dust harmful to the body is released. The main disadvantage of mineral wool insulation is considered to be increased sensitivity to moisture. When wet they lose their insulating properties. The presence of a foil layer reduces this likelihood. 
Natural cork. Thermal insulation for water heated floors is made from the bark of the cork tree. Using the pressing method, thin rolled material 3-4 cm thick and dense mats are obtained. The insulation is characterized by:
- safety - the insulation is environmentally friendly and hypoallergenic;
- good heat and sound insulation;
- resistance to rotting and destruction by rodents;
- geometry stability;
- waterproof.
Almost the only drawback of natural cork is its high cost.
Penofol. This type of thermal insulation for a warm water floor is made on the basis of foamed polyethylene. The polymer layer is covered on one (type A) or two (type B) sides with aluminum foil. A self-adhesive version (C) is also available.
If you plan to pour a concrete screed, then the ALP variety should be used in the underfloor heating system - the foil layer is laminated with a polyethylene coating.
The air present in the structure prevents heat loss, and the metal surface contributes to its reflection into the room. The total thickness of the insulation does not exceed 10 mm. Compact rolls are easy to transport and stack. Metallized lavsan film.
Non-flammable floor insulation, which has ideal reflective properties. The material is inert to aggressive chemicals and microorganisms.
Waterproofing properties guarantee protection of the system from moisture penetration from the basement or ground. The film is elastic, has sufficient resistance to deformation, and can withstand high loads.
The metallized layer is often supplemented with foamed polyethylene with a thickness of 2 to 10 mm. This improves thermal insulation performance, but reduces the flammability class of the material. Lavsan film can withstand temperatures up to +90 °C without destruction or deformation. This allows pipes to be laid directly on it.
| Insulation Indicators | Expanded polystyrene | Folgirov mineral wool | Cork | Penofol | Mylar film |
|---|---|---|---|---|---|
| Thermal conductivity, W/mK | 0,0336-0,035 | 0,035-0,045 | 0,036-0,042 | 0,037 - 0,052 | 0,031-0,037 |
| Moisture absorption% | 0,2-0,4 | 0,1-0,2 | 1 | 0,35-0,7 | 0,1-0,2 |
| Vapor permeability, mg/m h Pa | 0.05 | 0,49-0,60 | 0,2-0,6 | 0.001 | 0.001 |
| Flammability, class | G1-G4 | NG | G1 | G1 | G1 |
| Service life, years | 50-100 | more than 50 years | 20-25 | ||
| Operating temperature range, °C | -50 – +85 | -200 to +700 | -200 to +130 | from -40 to +95 | -60 - +100 |
| Sound absorption coefficient, % | 85-90 | 52 | |||
| Noise absorption, dB | 23-28 | 10-12 for black, 16-20 for white | 20-32 | ||
Manufacturers and prices
Many leading manufacturers offer high-quality insulation for underfloor heating. Some options are suggested in the table:
| Type of insulation | Brand | Options | Cost, rub. per m2 |
|---|---|---|---|
| Expanded polystyrene | Knauf Therm | 1200x600x47 mm | 500 |
| Ecopol | 1100x800x38 mm | 455 | |
| Foamshield | 1000x1000x50 | 270 | |
| Foil mineral wool | URSA (fiberglass) | roll 18000x1200x50 mm | 115-168 |
| Rockwool (basalt) | 342 | ||
| Technical traffic jam | Amorim | 1000×500×10mm | 560 |
| Penofol | Penofol | roll type A (B) | 47 (78) |
| Mylar film | Daewoo enertec | roll 1x30 m, thickness 3(5) mm | 139 |
Laying features
In order for the underfloor heating system to function effectively, it is important to perform all installation steps correctly. The installation of insulation plays an important role. Work begins with surface preparation:
- eliminating large cracks;
- leveling the base;
- waterproofing arrangement– the material is laid over the entire floor area with an overlap of 15-20 cm, the joints are taped;
- installation around the perimeter of the room damper polystyrene foam tape. It is glued to smooth walls, and attached to rough walls using self-tapping screws. The tape should be 2-3 cm higher than the finished floor.
After this, they begin laying thermal insulation. The slabs are laid end to end, without gaps. To avoid the formation of cold bridges, the joints are treated with sealant. The fastening method depends on the selected material.
Subtleties of connecting insulation with foil base
Insulation with foil is laid with the reflective surface facing up. This ensures efficient return of thermal energy into the room. During the installation process, care should be taken to ensure the correct connection of the individual slabs or strips. Regular construction tapes and adhesives are not suitable. You should use a special version of foil tape with an adhesive base.
Conclusion
Insulation for water heated floors allows you to effectively retain heat and guarantee a reduction in energy costs for heating. Additionally, they serve as sound insulation. The materials are presented in a wide range. The choice should be based on the characteristics of the premises and personal preferences.
Are you installing a water-heated floor system in a country house and it’s time to lay the insulating underlay? Agree that among the variety of offers of heat-insulating materials offered by manufacturers, it is sometimes not easy to make the right choice.
We will help you determine which insulation for a warm water floor is better. Together with you we will understand all the intricacies of assembling heat-insulating systems. We will examine the characteristics of popular materials and evaluate the key advantages and disadvantages.
Do-it-yourselfers will find installation instructions here. To make it easier to navigate the assortment offered by the building materials market, we have selected videos with recommendations for choosing insulation and installation.
Any instructions for installing a water heated floor for DIYers indicate that it is necessary to use insulation.
The insulation layer when installing a water floor performs several significant functions. It helps not only to ensure uniform heating of the room, but also, acting as a heat shield, can significantly reduce the energy losses of the system.
A screed laid on top of an insulating layer acquires the properties of a solid heat-transmitting element with a large surface area.
The main purpose of the insulating layer is to evenly distribute heat in the heated room, preventing its leakage through the floor slabs
Thanks to the uniform distribution of energy, the ordered convection heat flow begins to move at the same speed and in the same direction. As a result, evenly distributed heat waves will not form cold and hot areas on the floor, creating the most comfortable conditions for household members.
In addition, thanks to the direction of warm air flows along one course, it is possible to reduce energy costs for operating the system, while maintaining its power unchanged.
Types of insulation for water heated floors
There are many options for insulation for underfloor water heating systems on the modern market. The choice of substrate thickness is limited only by the material capabilities of the owner and the technical parameters of the room.
Absolutely all thermal insulation materials prevent the movement of sound waves through their thickness, and therefore are characterized by high noise absorption rates.
If there is a heated room under the base base, insulation with a thickness of 10-12 mm is sufficient, but if there is a basement or soil, a substrate of 30 mm or more will be required
Regardless of the design option, special requirements are imposed on the heat-insulating material:
- it must have a low thermal conductivity coefficient;
- absorb the load created by water-filled pipes;
- withstand the load of the screed laid on top of the pipeline;
- be resistant to dynamic influences that may arise during operation of the system, and after pressure reduction it must return to its original shape.
The desired effect can be achieved by using insulating material with a density of at least 35 kg/m 3 .
Option #1 - heat-insulating boards
In rooms where the ceiling height reaches 260 centimeters or higher, you can safely give preference to insulation materials based on a rigid polymer base.
Polystyrene foam or polystyrene foam. The basis for the manufacture of thermal insulation boards can be polystyrene foam or polystyrene foam.
The first option was created using a non-extrusion method; between its polymer cells there are channels for the passage of air and steam. Polystyrene foam has a low specific gravity and high vapor permeability.
In the manufacture of expanded polystyrene, the extrusion method is used, due to which the cells of the material are firmly sintered by the walls with each other. Because of this, the vapor permeability of the insulation is practically zero. But it has high strength and the ability to withstand significant mechanical loads.
The specific heat capacity of expanded polystyrene is slightly higher than that of polystyrene foam. In the first case it is equal to 1.34 kJ/(kg°C), in the second it is calculated at 1.26 kJ/(kg°C). The difference is small, but during calculations it can significantly affect the overall thickness of the floor heating system.
The standard size of thermal insulation is, for example, 120 cm × 240 cm. GOST number 15588-86 regulates the width from 50 cm to 130 cm, length from 90 cm to 500 cm.
The density of foamed polystyrene is 150 kg/m³, the same characteristic of polystyrene foam is 125 kg/m³. Depending on the specifics of production and the properties put into products by manufacturers, the characteristics of materials may vary.
Thanks to their unique composition, polystyrene boards act as good sound insulators, and their permissible load is about 50 kN/sq.m.
If we compare both types of material, foam plastic is disadvantageous because it is inferior in terms of density. Due to this, it is less resistant to deformation under mechanical loads.
This significantly reduces its thermal insulation properties. It is recommended to lay polystyrene foam in the structures of decking systems between joists.
Cork. Cork is often used for water and electric floors. Thanks to its special structure, which consists of miniature prisms of the correct shape, cork insulation is distinguished by significant compressive strength and lack of adhesion to cement mortar.
Due to the high cost of the material, cork is often chosen for residential premises, in which the base is already well insulated. Otherwise, to achieve the desired effect, you will need to purchase a technical cork with a thickness of at least 30 mm, which can significantly “hit your wallet.”
The main advantage of mats made from several layers of glued cork oak bark fibers is environmental safety
The only drawback of cork mats is that they are hygroscopic and are also available as single-component heat insulators. Therefore, when laying them, it is necessary to use an additional layer that will provide steam and water protection.
Mineral wool. An alternative, affordable option is to use mineral wool. It is available in the form of a flexible mat or a rigid slab.
Since, when laid in a screed, mineral wool is crushed under weight, which negatively affects its heat-shielding properties, this material is also best combined with decking structures assembled from wooden logs.
Using mineral wool as a heat-insulating layer, the heat transfer of a water-heated floor will be maximum
The only drawback of the material is the presence of penofol in the composition, which poses a danger to human health, and low moisture resistance. But properly executed waterproofing easily eliminates these shortcomings.
Option #2 - profile systems with guides
Profile systems help facilitate the installation of water circuits. They are created using hydropellent stamping technology, as a result of which shaped protrusions are formed.
Products come in two types: regular and laminated, which are covered with a vapor barrier film.
The bosses or guide grooves are located on the surface of the profile mats in even rows, between which it is convenient to lay heating circuits
The basis for their production is extruded polystyrene foam, which is created by squeezing the molten composition through the holes of the extruder.
The polymer base is famous for its resistance to moisture and high mechanical strength. The thickness of the plate itself can vary from 10 to 35 mm. The main thing is that it is proportional to the thickness of the finishing screed.
The side faces of each plate are equipped with locks, which make it convenient to adjust the elements, forming a continuous field, devoid of thermoacoustic seams.
The height of the cylindrical protrusions located on the surface of the plates reaches 20-25 mm. This is enough to conveniently place and securely fix water circuits with a diameter of 14 to 20 mm. Densely planted rows of bosses eliminate the possibility of shifting the laid contours during the process of pouring the cement screed.
The only drawback of profile systems is that it is impossible to install water circuits made from pipes of non-standard diameter in them
A special feature of the installation of profile systems is that after laying the water circuits in them, the structures are filled on top with a small layer of adhesive. And only after a day or two, when the glue has completely dried, the system is put into operation.
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Option #3 - roll insulation
Roll insulation is chosen for rooms where the distance to the ceilings is critical. Using thin foil layers with a protective lavsan coating, you can significantly reduce the thickness of the “pie”. The maximum thickness of such a substrate is only 9-12 mm.
The foil layer applied on one side of the insulation reflects thermal radiation well, thereby preventing energy loss
Rolled thermal insulation is equipped with a heat-reflecting shell made of lavsan or thermal insulation. Thin metallized materials perfectly reflect heat rays, so you can safely reduce the thickness of the insulation without fear of reducing the insulating qualities.
An important requirement when using foil options is that materials with aluminum foil cannot be used in the construction of floors with cement-sand screed. The alkaline environment of the mixture when pouring will simply corrode the aluminum layer.
However, if a protective film is applied over the foil, installation is possible. Use is permitted if the solution is mixed with gypsum and not with cement powder. Some manufacturers replace the foil layer with lavsan or polypropylene film, adding metallized inclusions to it.
In an effort to facilitate the installation process, many manufacturers apply special markings to the foil side of the produced roll materials, which serve as a guide for laying the heating circuit
The disadvantage of foil materials is that they reflect heat well, but do not insulate well enough. If the floor is laid above a basement, thin roll solutions are not enough.
Some craftsmen solve the problem by laying hard insulating mats not in one layer, but in two. But at the same time, the sheets are placed in such a way that the seams of the lower substrate overlap the seams of the upper one. This allows you to minimize heat loss.
Features of laying insulation
The substrate installation scheme depends on the type of materials used. But in any case, it must be placed on the most flat surface possible.
No. 1 - slab laying technology
The substrate, constructed from slabs with a mounting chamfer, is assembled easily - according to the principle of a designer. The slabs are easy to adjust and measure. You can cut the slabs to the appropriate sizes with a regular knife.
The simplicity of laying the substrate is convenient because during installation you can change the configuration of the circuits and the length of the pipelines at any time. To prevent the slabs of material from moving relative to each other during installation and operation, their joints are glued with construction tape.
In order to prevent the formation of heat-conducting bridges, the contour seams between adjacent slabs are taped with foil tape
Sequence of actions when laying insulation boards:
- Foam boards are laid on the cleaned and leveled base, fixing them with special plastic brackets, anchor dowels, or by placing them on an adhesive composition.
- A foil layer is laid on top of the laid and joined slabs.
- The top layer is lined with a reinforcing mesh, onto which the pipes are subsequently mounted.
If the concrete screed of the base floor is poured with significant deviations from the level or has rough cracks and unevenness, or the concrete slabs are laid with irregularities, it is better to build a frame before laying the substrate. To do this, wooden logs are assembled from dry and even timber with a section of 50x50, 50x100 or 100x100 mm.
The logs are placed at an equidistant distance of 60 cm, and pieces of mineral wool or foam boards are laid between them
A distance of 60 cm between the logs is considered the most optimal option, since this “step” does not require the creation of additional sheathing. The main thing is that the logs are located in the same plane and lie strictly level.
Thermal insulation boards must be tightly laid between wooden joists. If there are cracks, they must be filled with foam.
When laying slabs of extruded polystyrene foam, it is necessary to observe some nuances:
The damper tape is installed around the perimeter after the installation of the heat-insulating layer. Its edge must be partially placed under the insulation, partially placed on the wall
It is not necessary to lay waterproofing on top of extruded polystyrene foam. However, a substrate with marked cells will make it easier to install pipes with the required spacing
No. 2 - installation of roll materials
The roll material is laid on a carefully leveled base and fixed to the base using tile adhesive or double-sided tape. Cutting strips of the required size is done with ordinary office scissors.
To compensate for the thermal expansion of the screed, it is recommended to place the foil layer slightly overhanging the wall.
The foil material is placed with the metal side up so that the metallized surface best reflects heat
When laying rolled materials, they are guided by the markings of the printed installation markings. It determines the distance between the contours and makes it easier. Typically, rolled materials have allowances of foil polymer film at the edges to allow connection of adjacent webs.
When laying sections, pay special attention to expansion joints. To do this, the joints of the laid strips are glued with one-sided construction or metallized tape. If cork is used as a substrate, then before laying it it is necessary to take care of reliable vapor and waterproofing.
No. 3 - mat installation diagram
The stage preceding the laying of mats is the installation of film waterproofing. After laying it around the perimeter of the room, strips of damper tape are glued along the bottom of each wall.
Mats are laid on the prepared base, fastening the slabs together using a locking system. To reliably fasten slabs of small thickness and light weight, use the adhesive method and use plastic harpoon staples.
Some manufacturers, for ease of installation, include edge strips complete with mats, which can be used to conveniently mark areas of exit from the heating zone
An important point: when laying mats, it is not allowed to use metal fasteners, since they can damage the integrity of not only the heat insulator, but also the waterproofing.
In order not to make a mistake in choosing insulation for a water floor, be guided by the technical characteristics of the room, taking into account not only the thickness of the product, but also the maximum permissible compressive load.
By choosing a heat insulator wisely and observing all the details of installation, you can create a reliable foundation for arranging a functional floor water system.
Would you like to talk about how you selected and installed insulation under the heating floor in your home? Have questions or valuable recommendations? Please write comments in the block below.
Recently, the “warm floor” system has become a very popular type of heating. The main advantage of the system is significant saving fuel used. It is also important that installing the insulation is quite simple; you can cope with the task yourself. However, there are points that knowledge is necessary for high-quality installation of such heating. An important point is the installation of thermal insulation for a warm electric floor.
A floor heating system will release a large amount of heat into the concrete the floor is made from. In this regard, additional fuel costs are inevitable, there will be no more savings. Thermal insulation is laid under electric heated floors in order to avoid unnecessary fuel consumption.
Along with decreasing natural heat losses, sound insulation also increases. The floor covering also prevents moisture from entering from the basement or ground.
Types of systems and materials used
There are several types of insulation systems, they depend on the raw materials used. Thermal insulation for heated floors is made from natural and synthetic materials.
Main types:
Cork insulation
Use cork oak bark. The purchased insulation is rolled into a roll with dimensions of 10 m * 1 m * 1 - 10 mm. During installation it fits well and does not require gluing. Has excellent qualities. Some types have a rubberized base, which increases waterproofing properties.
During installation, a thermal reflector must be used so that the heat from the system is reflected to the floor surface.
This is a modern heat-insulating raw material of synthetic origin. It is made of porous polypropylene and has a cellular structure. Markings make installation easier, but they may not exist. The heat-reflecting layer is made of aluminum foil. Penotherm increases thermal efficiency by up to 70% if installed correctly. Available for sale in lengths of 10 or 30 m, width 1.2 m, thickness varies.
Artificial heat insulator - "Penofol"
It is made from foamed polyethylene. It has a foil heat-reflecting layer, the thickness of which is 100 microns. The surface can be different, due to which it is divided into 4 subspecies:
- a) “A” - the foil layer is on one side.
- b) “B” - made using foil on both sides.
- c) “C” is foil on one side and has an adhesive base on the other.
- d) “ALP” - foil on one side and polyethylene film on the other. Roll thickness 3 mm, width 580 mm, length 15 m.
Thermal reflection has a coefficient of up to 97%.
Made from foamed polyethylene, has a bubble structure and a layer of foil. There are cross-linked (PPE modification) and non-cross-linked (NPE). They differ in their service life: PPE foilisolon lasts much longer.
It has good characteristics and retains heat well. It is sold in the form of sheets, rolled into rolls, and may or may not have markings for laying on the floor. Roll sizes vary. An excellent raw material for installing underfloor heating in cool rooms. The foil layer must contain lamination.
Thermal insulation installation technology
Thermal insulation using any thermal insulation material under a warm electric floor is quite simple to perform. No special skills are needed for this work; it is enough to understand the work and be able to use the tools.
Step-by-step installation of thermal insulation
- The base for installation must be level and strong.
- It is necessary to properly waterproof the base, after which you can install the raw materials.
- If you are creating a water type floor with heating, you need to take into account the weight of the pipes with the coolant. After all, after some time they will push through the heat-insulating material under the mechanical influence of the weight of the screed and floor covering. To prevent this situation, you need to choose a material with high strength, and surround the pipes on both sides with reinforcement. Thus, the mass of the screed and floor covering will be distributed evenly onto the mesh. It is also better to install slabs of extruded polystyrene foam with special grooves for pipes.
- All joints and seams of the insulation must be taped using foil tape. This way, more warmth will be retained.
- To maintain the integrity of the concrete screed, the joints between it and the wall must be covered with damper tape.
Thermal insulation when installing floor heating is not a luxury, it is a necessity. Incorrect installation will lead to negative consequences that will negatively affect the quality of heating. They will also affect the homeowner’s wallet, because fuel costs for heating will increase.
Thanks to the rapid development of modern technologies, various devices are increasingly being used for home improvement to increase the level of comfort of residents. One of these devices is heated floors. And for its productive operation and functioning a number of materials are required, among which thermal insulation occupies a special place.
The task of underfloor heating, regardless of type and configuration, is to ensure uniform distribution of warm air in the room. Since everyone knows that cold air accumulates at the bottom, and heated air rises, the difference in temperature is quite noticeable for humans. A system of warm electric or water floors minimizes these temperature fluctuations in the home, creating acceptable and comfortable heat exchange.
The main feature of the device can be considered the thermal insulation substrate, which, along with the entire heating system, is responsible for heat conservation.
Among the proposed range of similar products on the modern market there are a number of materials that are used to construct the system.
In order not to make a mistake with the choice of raw materials, you should proceed from the tasks that the product will solve as part of the entire installation of heated floors.
- Among the main functions of insulation it is worth highlighting the following points:
- The presence of thermal insulation reduces the natural loss of heat that escapes through the coldest areas of the apartment or house to the outside or into the ground. In the absence of any materials for insulation, the level of release of warm masses from the room through the floor surface is 20%.
- Thanks to the installation of insulation, thermal energy circulates proportionally throughout the entire heating area, eliminating unnecessary heating of the floors and other components of the building structure that are located under the floor.
- Thanks to thermal insulation, you can save money spent on heating your home.
- The properties of thermal insulation products make it possible to create a protective barrier that prevents moisture from entering the home from basements or soil through the floor covering.
Insulation for underfloor heating
"Heated floor" device
Heated floors today are one of the most attractive systems for additional heating of a room, both in individual housing construction and in apartment buildings. When installing this system, all manufacturers of “water heated floor” systems recommend thermal insulation of the floor to prevent the radiation of thermal energy in undesirable directions. In other words, by installing a “warm floor” on a concrete screed, you will not heat your neighbors below, the basement or the foundation of the house. By laying insulation over concrete under the PENOPLEX ® heated water floor, you can avoid wasteful heat loss and energy costs. In most cases, additional waterproofing of PENOPLEX ® thermal insulation under a heated floor is not required, since this material has almost zero water absorption.
This is especially true for the bathroom, since this room is a place with high levels of humidity. Thermal insulation of the bathroom will prevent the formation of condensation, which has a detrimental effect on the decoration of the room.
Installation instructions:
- A layer of thermal insulation of PENOPLEX ® boards is laid on the floor panel. The “warm floor” construct is made directly on them (according to the recommendations of the suppliers). If the hydromembrane is located under a layer of PENOPLEX ® slabs, flexible heating pipes can be attached directly to the slabs. To prevent cement “milk” from getting into the seams between the insulation boards, the seams must be closed (glued with tape) before pouring the screed;
- If a hydro- or vapor barrier membrane is placed on top of PENOPLEX ® slabs for fastening flexible heating pipes, it is necessary to use an additional layer to ensure continuous waterproofing. Particular attention should be paid to the execution of expansion joints. In addition, measures should be taken to prevent the formation of heat-conducting bridges at the joints between the plates;
- It is not recommended to lay laminate flooring on PENOPLEX ® without a load-distributing screed device. As a screed, you can use either a reinforced CFRP screed with a minimum thickness of 40 mm, or two layers of slab materials (gypsum fiber board, gypsum fiber board, etc.) to overlap the joints.
High-quality insulation of a heated floor at the construction or insulation stage will bring you a visible bonus in the form of significant savings on heating the house, a long period of maintenance-free operation and, most importantly, comfort and coziness for the whole family. PENOPLEX ® slabs are the most optimal insulation for floors.
How to insulate the floor between heated rooms. Warm floor design
The role of PENOPLEX ® in the case of the operation of heated floors between heated rooms is to reduce the degree of radiation of thermal energy in undesirable directions. It is in this case that, due to the absence of heat flow dissipation, energy costs are significantly reduced (otherwise, not only your floor is heated, but also the ceiling of your neighbor or basement, respectively).
When insulating floors between heated rooms, including in a “warm floor” design (mandatory), the required thickness of PENOPLEX ® is 40 mm.
Approximate consumption of materials
Estimated consumption of materials when insulating an open balcony with a concrete fence (loggia) with an area of 4 m2, with a ceiling height of 3 m.
Which insulation to choose for water heated floors
- Content:
- Why do you need insulation for water floors?
- Plates
- Rolled thermal insulation
- Features of laying insulation
Almost every instruction for installing a water floor yourself indicates the need to use insulation. The insulating layer helps distribute heat evenly throughout the room. Insulation for water heated floors reduces heat loss and ensures uniform heating of the room.
Why do you need insulation for water floors?
According to the installation instructions, a layer of thermal insulation must be included in the cake under a warm water floor. Although some installation teams neglect to lay the insulating layer, this is a gross violation of the rules for laying the heating system.
Why do you need insulation anyway?
- A special heat-reflecting substrate under a water-heated floor serves as a kind of screen that prevents thermal radiation from escaping in the wrong direction. Simply put, with the help of insulation, the heating system does not heat the apartment of the neighbors living below, but its own home.
- The use of the underlay serves another purpose related to the peculiarity of the operation of heated floors. The substrate evenly distributes thermal energy throughout the room, allowing the convection heat flow to be stabilized in one direction and at one speed.
- Thermal insulation mats for water heated floors with bosses make it easier to install the water circuit. The design of such a system includes special latches, thanks to which laying and fixing the pipe is carried out quickly and reliably.
Types of insulation for underfloor heating
Although there is a large variety of thermal insulation available, it can really only be divided into two categories.
Plates
This category includes polystyrene foam and polystyrene foam under a warm water floor. The advantage of polystyrene systems is their high strength and ability to withstand mechanical loads.
This group should also include a profile mat for installing a warm water floor. The use of a profile system (bobs or guide grooves) is very convenient for laying pipes.
Profile guide mounting mats for water heated floors, after laying the pipeline, are filled with a small layer of adhesive solution on top. After drying for 1-2 days, you can begin operating the heating system.
Polystyrene foam for heated floors is an unprofitable option. After laying, the slabs are easily deformed, after which the thermal insulation ability of the material decreases.
Rolled thermal insulation
Enjoys well-deserved popularity. Foil reflective thermal insulation for water heated floors allows you to reduce the thickness of the “pie”. The foil effectively reflects thermal radiation.
Foil insulation for water heated floors often has special markings that facilitate installation of the heating circuit. The thickness of the roll type substrate does not exceed 1-1.5 cm.
Mineral insulation is rarely installed, since a protective layer will need to be laid on top. It is not advisable to use mineral material for the substrate.
According to customer reviews, one of the best solutions is to purchase Teploizol type insulation.
You can also use cork insulation. Cork insulation has good performance in terms of: compressive strength, sound insulation and lack of adhesion to cement mortar.
When deciding which thermal insulation material to choose, you should be guided by the technical characteristics of the heated room. Possible disadvantages of the substrate should be taken into account: cost, thickness, maximum permissible compressive load, etc.
How a water floor pie should look like in layers
The preparation of the cake under the floors must be carried out in strict accordance with the manufacturer's recommendations. Installation work is carried out as follows:
Laying a warm water floor on mats, as shown by a comparison of thermal insulation materials (their technical characteristics and difficulties associated with installation), is more appropriate. The permissible load on the polystyrene foam system is 50 kN/m². The weight of the structure allows installation even in high-rise buildings on the top floors, where the use of concrete pie is prohibited.
Additionally, laminated extruded polystyrene foam with bosses is resistant to moisture, easy to install and facilitates installation of the water circuit. The only drawback of polystyrene material is its cost. But if you consider that plastic mats do not require additional components for fixing pipes and subsequent screeding, then the difference in price becomes not so significant.
Thermal insulation for heated electric floors, which one to choose?
Currently, many people install engineering systems in the form of heated floors in their homes. 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 an electric-type heated floor. It is installed instead of the main heating system during the construction of private mansions and when performing renovation 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 tribute to a fashion trend, but a necessity, which is caused by the following factors:
- creating comfortable conditions;
- health care;
- savings.
Structure of electric heated floor
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.
A warm electric floor is a complex structure; 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, helping to save electricity consumption and household money.
Features of electric floor heating
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. The body will be healthy only when the 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 final floor covering after installing the 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 to the 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 installed in special mats with a certain pitch, 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 electrical liquid system consists of 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;
- 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 a long service life.
Types of thermal insulation
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.
Cork thermal insulation
- 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.
- Insulation "Penotherm"
"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.
Material "Folgoizolon"
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.
Insulation film
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, a T-shaped damper profile is used to separate them.
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.
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.
Choosing insulation for water heated floors
The installation of a water heated floor requires competent design and strict adherence to technological standards. The choice of insulation is one of the important points. Let's consider the main types of thermal insulation materials, their properties and characteristics.
Which insulation is better
Insulation is a mandatory element of a warm floor. Without it, the system will not be economical, and most of the energy will be lost on heating the underlying floors or ground. This issue arises especially acutely when installing a system on the ground.
So, what thermal insulation materials are advisable to use when installing water heated floor systems? In general, any material that meets certain characteristics is acceptable. First of all, it must have a sufficient level of thermal insulation, also be resistant to moisture and chemicals from the concrete screed, and have sufficient rigidity.
To one degree or another, the following materials meet all these requirements:
- expanded polystyrene (foam);
- extruded polystyrene foam;
- mineral wool slabs;
- foamed polyethylene (penofol);
- natural cork.
Let's look at each of them in more detail.
Expanded polystyrene
Expanded polystyrene (EPS) is popularly called polystyrene foam. This material is obtained from polystyrene by foaming. In addition to polystyrene itself, the insulation composition includes a large number of additives and modifiers that improve its properties. Thanks to foaming materials, up to 98% of the volume of EPS consists of air bubbles. 
Let's look at the characteristics and properties of expanded polystyrene. The heat transfer coefficient, which is the main characteristic of thermal insulation materials, in polystyrene foam varies from 0.030 to 0.047 W/m °C. It depends on the manufacturer and the density of the material. PPS is produced in different densities, which determine the rigidity and weight of the material. In this case, thermal conductivity depends little on density.
Expanded polystyrene is a flammable material. Also, when heated to a relatively low temperature (about 80 degrees), harmful substances can be released from it. Other characteristics of this material include:
- resistance to fungi and microorganisms, but the material can be destroyed by rodents;
- PPS does not absorb water well (it is not hygroscopic), which is convenient when installing it in a wet screed.
Expanded polystyrene is convenient to use and is often used in underfloor heating systems.
Extruded polystyrene foam
Extruded polystyrene foam (EPS) is a type of polystyrene foam. It is produced in the same way as PPS, the only difference is in the method of producing granules. Its characteristics include low thermal conductivity 0.029 – 0.034 W/m °C, and not high hygroscopicity. 
Different types of EPS are produced, with a density from 25 to 45 kg/m³. In terms of thermal performance and lightness, it exceeds polystyrene foam up to grade PSB-35 and is similar to the characteristics of high-density polystyrene foam.
This material is tougher and better able to resist mechanical stress than expanded polystyrene, so it is more convenient to use and is less susceptible to destruction. The main disadvantage is its price is higher.
Please note: Both EPS and regular polystyrene foam are produced in a special modification for heated floors, in which a system of special grooves and channels is made on the upper edge of the slab for laying the heated floor pipe. This makes the job easier.
Mineral wool boards
For underfloor heating systems, rigid slabs of mineral basalt wool are sometimes used. Its characteristics are similar to ordinary mineral wool. The difference is in rigidity and ease of installation. The main positive characteristics of mineral wool include:
- zero flammability - the material is not exposed to high temperatures;
- high noise insulation characteristics;
- good thermal insulation properties;
- chemical resistance.
For screed construction, rigid mineral wool boards with a density of 175 to 200 kg/m³ are used, the thermal conductivity of which is about 0.039 W/m °C. The main negative property of mineral wool is hygroscopicity and vapor permeability. Because of this, when installed in a wet screed, they require careful hydro and vapor barrier.
Foamed polyethylene
Recently, foamed polyethylene has been used for thermal insulation of heated floors. It is a rolled material with a thickness of 3 to 10 mm. Foamed polyethylene can also be foil-coated on one or both sides. Foiling allows you to create a reflective layer for infrared rays. The use of foil allows you to reduce the thickness of the required heat insulator.
However, there is a nuance: the reflection of infrared rays by such a layer is difficult in a solid body such as a cement screed. But still, the use of such material allows you to significantly save on the height of the screed. This will avoid reducing the height of the room.
In terms of its thermal characteristics, foamed polyethylene is similar to expanded polystyrene and other materials. The thermal conductivity coefficient of this material in a dry state is in the range of 0.037 - 0.049 W/m °C, but it must be borne in mind that foamed polyethylene absorbs water, and at the same time its thermal insulation properties are reduced.
It is also important to know that foil can be corroded by chemical materials in the concrete mixture. To eliminate this problem, many manufacturers produce sheet material that is coated on top of the foil with special polymer films.
Natural cork
For water heated floor systems, a natural thermal insulation material – cork – is also used. Cork has a U-value of 0.034, similar to the best man-made materials. The main positive characteristic of cork is its naturalness. It does not contain foreign chemical additives or harmful substances.
The main disadvantage is the high cost. The use of natural cork in a cement screed for a heated floor is mainly justified by its naturalness. But the question arises: is it worth pouring expensive and natural material into cement?
Cork is a relatively hygroscopic material. It can absorb up to 12%. In order to protect the cork insulation from getting wet, it must be covered with a dense layer of polyethylene or polyvinyl chloride film with or without foil.
"Pie" of heated floor
After analyzing the possible types of insulation for water heated floors, we will analyze the composition itself, the so-called pie. After all, the quality of the system depends not only on the correct choice of insulation, but also on proper installation. In what order are all layers of water heated floors installed?
The order also depends on what the system is mounted on. If the installation of a heated floor is on a soil base, then first of all it is advisable to arrange a rough concrete screed on which the cake will then be laid.
- insulation of the required thickness, and when installed on the ground, the thickness of the insulation can reach 150 mm, and for ordinary floors the thickness of the insulation is selected up to 50 mm;
- if the insulating material is not covered with protection on top or there is no system for laying pipes on it, then it must be covered with a vapor barrier film to protect it from moisture from the cement mortar (except for foam plastic and EPS);
- further, a special panel for laying pipes or a reinforced frame is installed to create rigidity;
- The pipeline is attached to the frame or panel.
The entire system is ready for pouring the screed and installing a decorative floor covering.
Warm floor diagram.
When choosing a thermal insulation material for a water heated floor, you need to focus on financial capabilities and accessibility. For most applications, extruded polystyrene foam or regular polystyrene foam boards will be suitable. If it is not possible to arrange a thick screed, foamed polyethylene is used. Mineral wool boards are most often used when installing a system in a wooden floor. But it can also be used in cement screed. Cork is for connoisseurs of natural materials.
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Currently, many people install engineering systems in the form of heated floors in their homes. 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 an electric-type heated floor. It is installed instead of the main heating system during the construction of private mansions and when performing renovation 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 tribute to a fashion trend, but a necessity, which is caused by the following 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.
A warm electric floor is a complex structure; 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, helping to save electricity consumption 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. The body will be healthy only when the 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 final floor covering after installing the 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 to the 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 installed in special mats with a certain pitch, 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 electrical liquid system consists of 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;
- 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 a long service life.
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.
Cork thermal insulation
- Modern thermal insulation materials of artificial origin for electric floors include the following products:
- Insulation "Penotherm"
- "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, a T-shaped damper profile is used to separate them.
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.
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.