Laying the floor heating cable under the tiles

Surface preparation

The technology of laying a warm floor provides for thorough preparation of the surface before laying heating elements. Heating mats or cables can be laid only on a clean and level floor without any protrusions or cracks. It is possible to use primer, concrete screed or filler floor.

Surface insulation

laying, floor, heating, cable, tiles

To minimize heat loss and achieve effective heating of the room in the preparation of the heat insulation layer is used. Depending on the required thickness of insulation, the following materials are used:

On balconies, loggias, over unheated rooms or basements use thick insulation materials to 100 mm (such as polystyrene foam and styrofoam). Foil foil is used for a thin layer of insulation (the reflective surface of the foil should be directed upwards). All joints and seams are hermetically sealed with foil tape. Floor heating under the tiles in the bathroom is additionally equipped with a layer of waterproofing.

What is needed for laying underfloor heating under tiles

To equip themselves with a warm floor under the tiles can be several ways, but for laying in an apartment is the easiest, cheapest and most effective. the use of so-called heating (or heating) mats for floor heating. Heating mats is a thin electric heating cable in a special shield (for protection against electromagnetic radiation), which is “coiled” attached to a fiberglass mesh; for connection to the mains heating mat is equipped with a so-called “cold” end. A section of an ordinary electric wire. Such a design greatly simplifies the selection and further installation of floor heating. As a rule, all manufacturers produce mats 50 centimeters wide (the width of the fiberglass mesh), and the length of the mat depends on the heating area for which it is designed. The thickness of the mat is from 3 to 5 mm (depends on the manufacturer). This makes it possible to equip themselves with a warm floor system with minimal loss in the height of the room.

One of the main characteristics of heating mats is their power. This parameter is worth paying attention to when selecting the right heating mat. In general, the following values are recommended for such heating systems as underfloor heating:

  • For additional comfortable heating of the floor surface in the dry room. 110-140 W/m2
  • For underfloor heating in damp rooms. 140-160 W/m2
  • For underfloor heating on loggias, balconies in conservatories. 180-220 W/m2

Today, there are heating mats on the market for all types of applications.

When arranging a system of underfloor heating under the tiles (in addition to the heating mat itself for a certain heating area), we will need:

  • Thermostat. This is a device that serves to control underfloor heating. The thermostat, using a temperature sensor mounted in the floor pie, measures the floor temperature, compares it to the set temperature and, depending on the result, activates or deactivates the heating. Example. For rooms with permanent occupancy, we recommend a floor temperature of not more than 26°C (according to current SNIP). We set this temperature on the thermostat and if the current floor temperature is lower, the thermostat will turn on the heating, heat the floors to 26 degrees and turn off the power to the floors. After the floor has cooled down to a temperature of 24-25 degrees, the thermostat will turn the heating back on and heat the floor to the set temperature. Then the whole process repeats. Using a temperature controller allows you to achieve maximum comfort and significantly save energy.
  • Standard sub-socket (mounting box) for installing the thermostat in the wall.
  • floor “pie”. So that it can be replaced if it fails, the sensor is not immured in the floor layer, but installed in a corrugated tube, so that if necessary, it can be removed and installed another. Some manufacturers have corrugated tube included with heating mat.
  • Tile and tile adhesive. You can use tile, porcelain tile or natural stone. Adhesive is chosen depending on the type of tiles and operating conditions.
  • Drill with a drill bit to install the thermostat, an angle grinder with a wheel on the concrete or chisel cutter, construction tools.
  • Multimeter for resistance measurement.
  • Safety disconnect device (RCD) with a leakage current not exceeding 30 mA. Connecting the floor heating under the tiles (especially in wet areas) should be carried out through RCD with a leakage current of no more than 30 mA.
  • In addition may need: a glue gun for attaching the mesh mat to the subfloor surface, a metal adhesive tape to fix the heating cable when bypassing the drain holes t.д.

Installing electric underfloor heating under a tile is not difficult. The heating mat is laid out and attached to the subfloor, and filled with screed. You can’t cut the cable, but you can cut the mesh to which the heating cable is attached.

Self-installation of electric underfloor heating under the tile

The grid is needed for easy installation of cable under the tile.

Independent installation of electric underfloor heating under tiles. The distance from the wall 10 cm.

In the instructions write that under the bottom of the floor heating is necessary to lay insulation. But I didn’t do it, because I have a basement under the floor, and the heat will go there, it won’t hurt in winter. Another doubt about the quality of adhesion of tiles to the floor, if the screed with a warm floor will lie on the insulation.

Cable electric floor heating installation under the tile

Then invited a tiler, who laid tile on top of the screed with the floor.


Electric underfloor heating comes in several varieties:

    – There is a separate article about it. The thinnest option, but it is made for “dry” installation under the laminate and linoleum, under the tiles it is better not to use;

  • Cable. a separate wire, which is laid with the spacing you choose, due to which you can achieve more intense heating. In order to have it heated more or less normally, you should buy not less than 15 W per running meter and install it with a spacing of not more than 10 cm. According to the technology, it is installed into the 4-5 cm thick screed. Approximate power consumption is 150-200 W per square meter.
  • Mats are pre-wired cables fixed on a grid. On sale you will mostly find 120 and 160 W/m2 wattage mats. There are very weak variants (100 W/m2), and there are more powerful 180 W/m2 (Thermo).
  • Stranded. is another type of infrared heating, which is optimal for installation in the tile adhesive.

How to Install a Heated Floor System

The heating mats and floor heating rods are best suited for tile adhesive installation. We only cover the installation of heating mats in this lesson, because the core system is the subject of a separate article.

In practice, anything less than 150 W/m2 is practically useless. The power of 150-165 W allows you to heat up to a comfortable temperature, but it takes time. Mats with a power of 180 W/m2 allow faster heating of the floor surface and they are not mounted in the tile adhesive, but in the upper layer of the screed.

The surface takes half an hour or more to heat up, and after it is turned off, it cools down in a couple of minutes. If you look at those. the passport to some manufacturers, you can see heating to a given temperature for up to 24 hours.

In fact, people rarely use heating. Usually it is turned on in two cases: to show off when guests come and in the off-season, when the heating is turned off.

Power Consumption

Electric floor heating is only beneficial in small areas

To calculate the consumption of electricity, you need to know the total power of the mat in the entire area, multiply it by the percentage of active daily operation of the system and then calculate the monthly consumption, multiplying by 24 (hours) and 30 (days).

  • You have a 4 square meter bathroom. Of these, only two meters of electric cable will have a capacity of 180 W/m2.
  • The total power of the system will be 360 W/m2.
  • In “automatic” mode the floor heating will run 60% of the day. Multiply 360 by 0.6 and you get 216 Wh.
  • Energy consumption per day: 21,624 = 5,184 kW.
  • Energy consumption per month: 5,18430 = 155,5 kW.
  • If you calculate the costs at the current price of 1 kW of 4.68 rubles (in Moscow), it will cost 728 per month to heat the bathroom.

Consumption can be reduced by using expensive programmable thermoregulators due to the efficient power control.

If you want to install electric underfloor heating in a large area, you need to consider the maximum load on the wiring. The load limit can vary, but a rough value according to SNiP 31-02 “Electric Power Supply of Residential Buildings” is 8.8 kW per apartment with an electric stove.

Instructions for laying an electric floor heating cable under the tile with your own hands

Before you start the work, take care that the surface of the floor is flat, it must be cleaned of debris and leveled. For this purpose, cement mortar is usually used.

Important! It is necessary to determine the highest point of the floor in the room and, focusing on it, create an even surface. At the same time, it is recommended to check the quality of work with a level.

To ensure quality adhesion, the surface is primed. If there are any cracks, they are sealed with a cement mix.

Selecting the design for the floor

Before you do with your own hands electric warm floors under the tile, you need to choose the most convenient option. In this case it is necessary to take into account the peculiarities of different structures. Particular attention should be paid to the heating capacity of the structure. You have to take into account that the heat should be neither too much nor too little.

Thermal insulation

On the leveled floor it is necessary to put a thermal insulation layer. The floor heating will be installed on it.

Important! This step is necessary, so the heat from the heating will not go down through the floor, and all come into the apartment.

Installing the thermo regulators and sensors

The first thing to do is to install the electronic thermostat correctly. To do this on the wall make a socket. Its standard diameter is 73 mm. Electrical wiring must be connected to it.

There are several types of thermo regulators

Down from the socket in the wall make a groove with a cross section of 20×20 mm. The power supply wire for the electric floor heating will be led through it. This hole is first made with an angle grinder and the inside is machined with a torch. In the floor it is also necessary to make a slot with the same cross section, it will be used to install the sensor.

A temperature sensor needs to be installed. It is placed in a narrow corrugated tube and laid horizontally, at an equal distance between neighboring cables parallel to them. Lead the wires from the sensor to the wall of the room.

The height of the thermostat should not be less than 30 cm from the floor. If the work is carried out in a room with a lot of moisture (for example, in the bathroom), the regulator needs to be taken outside. The room’s furniture should not obstruct access to the heat regulator.

Installing the cables

When laying the cables, you must take into account what kind of construction you want to use. They can be in the form of wires, single-core or double-core cables or thermo mats. For each of them there are rules for laying the cable.

Usually a single core cable is used for this, it is laid in a loop so that it covers the entire area of the room. Both ends of the cable must extend to the thermostat. Before laying it is recommended to draw a diagram, according to which the work will be done.

Check the quality of connections with a multimeter

Before installing the screed, you need to do a test run and make sure everything works properly.

If a thermo mat is used, it is simply rolled out onto the surface. If necessary, cut into pieces and connect the wires on them.

It is convenient to mount the cable on metal strips that have special holders.

In some areas of the apartment installation of floor heating is impractical. Usually in this case there are areas where heavy furniture will stand. When laying the floor, it is recommended to bypass these places.

Screed Casting

Cement screed will fix the cable. To lay it, make a mortar, pour the finished design of the warm floor, and ensure that the surface of the screed is even. Usually it is used for those cases where single-core or double-core cables are used. It is not used when laying thermo mats or wires.

Important! When installing screed, remember that the complete drying of the cement mixture occurs after 28 days.

Laying tiles

First, conduct a preliminary layout of the tiles as they will stand later. Then the mortar is put and smoothed with a trowel. It is important that the tiles are laid in even rows. To do this, lay the mortar carefully and use a putty knife to level it out. When installing tiles, it is necessary to control the correctness of the installation and correct its position, if necessary. It is important that the flooring is level.

“Underfloor heating” with a heating cable

It is one of the most qualitative solutions in floor laying. The installation principle is simple. a wire is laid in a serpentine manner on the prepared base and fixed with special clamps. Preparation involves laying thermal insulation with a reflector to give the heat to the top. Then the indicators are installed at the calculated place, and then begin laying tiles.

The main disadvantage of this solution will be the need to screed to protect the cable from damage of mechanical nature. Some experts believe that it is possible to install wiring directly into the tile adhesive. However, this is not recommended for 2 reasons:

  • The glue is significantly more expensive than the materials used for the screed.
  • When, over time, it will be necessary to replace the tile or a fragment of it, during the dismantling there is a risk of damaging the heating cable.

Important! Heating cable is extremely comfortable to lay, as it will bypass all obstacles (for example, the toilet bowl). However, it is likely that expert advice will be required in calculating the length of electrical cable.

Step-by-step installation of electric underfloor heating

Material is determined and bought, as well as consumables and mortars are purchased, along with the necessary tools. The time has come to learn how to conduct the correct installation of electric flooring under the tiles.

Drawing a wiring diagram

No electrical installation is carried out without first drawing up a diagram, which must be displayed:

  • Connection point.
  • Number and type of heating elements.
  • The cross section of the power cable.
  • Switching elements.
  • Protective elements.

Before you create a scheme, you need to familiarize yourself with the generally recognized rules of installation of electric underfloor heating:

  • Throughout the room heating elements should not be less than 10 cm from the walls.
  • It is necessary to know in advance where the furniture will be placed, which will interfere with heat dissipation, which could lead to overheating the conductor.
  • The boards or cable can be laid diagonally. This will help reduce the amount of material consumed and focus only on those areas where heating is required, bypassing the “dead” zones.

Now the scheme should be transferred to paper. Professional electrical installation companies design the home network using special programs on the computer, but for self-installation of underfloor heating, a simple sketch will suffice.

Calculating the amount of material needed

When calculating the total value should be subtracted from the places where the furniture will stand after installation. But how to determine the power of the underfloor heating in the bathroom under the tile and the number of heating element? To do this, you should use generally accepted values and formulas.

The average power of an electric floor per 1 m² is 140 W. But provided that the room is well insulated, this figure can be reduced to 80-100 W per 1 m². Having determined the power of the cable laid in the future, it should be multiplied by the working area. For example:

We choose the power of one meter of cable, it will be enough 20 W/m. And divide the total power by this figure:

This will be the total length of the heating cable for heating 10 m² of floor space. If you take the power of one meter more, and the total reading will be more, respectively, will increase the cost of the material.

The device of the electric floor requires a reliable fixation, so in addition to the cable or mat for heating, you need to buy an installation adhesive tape, with which it is very convenient to attach the heating element to any surface.

Prepare the work surface

The preparatory stage is usually the most laborious, requiring a lot of time and effort. The preparation of the working surface will require:

  • Remove old flooring, whether wood planking, laminate, tile, or simple linoleum. Cleaning should be made to the concrete surface.
  • If the concrete surface under the old floor is uneven, then by pouring a small amount of concrete mortar (thickness of 2-3 cm is enough), it must be leveled. This is a rough version, so the main goal is not aesthetics, but smooth smooth.
  • Final removal of both large and small floor debris.

When installing the screed, you must remember about the metal mesh, otherwise after a while the concrete surface will crack and the floor will sag.

Install a thermal insulation layer

Installation of electric underfloor heating begins with the laying of thermal insulation. A quality thermal insulation layer not only increases the efficiency of the system, but also makes energy consumption more economical, which is very important especially during the heating season.

The order of laying the thermal insulation layer:

  • Stretch the roll of insulation over the entire area of the room, making sure that the material is 10-15 cm over the walls.
  • If the material has an adhesive layer on one side, it can be immediately glued to the concrete surface.

Important! For quality adhesion of thermal insulation, the concrete surface must be cleaned from large and small debris.

For thermal insulation for a concrete floor, it is best to use polyethylene foam, with an additional foil layer. It is not worth spending extra money, so a good and economical option is to use thermal insulation with foil on one side only. On the other side, for ease of installation, there should be an adhesive layer.

Laying of metal mesh

Metal, not reinforced, mesh is needed as a base, on which the heating element will then be placed. The mesh, as well as the thermal insulation layer, is mounted on the floor in the room, but without overlapping the walls. Do not attach it to the concrete surface through insulation. Do not buy expensive galvanized or stainless steel products. a simple metal mesh will do.

Installing the hole and the temperature sensor

The first step, which belongs directly to the category of electrical installation, is shrewd concrete surface for laying the temperature sensor. This should be done before installing the heating element.

  • Determine a location for the temperature sensor. Usually it is near the nearest light switch, which is very convenient for both installation and future operation.
  • Make a hole between the thermostat and the place in the floor where the temperature sensor will be located.
  • Install the sensor and the cable from it in a corrugated tube, and place the corrugated tube in the tunnel.
  • Fasten the corrugation with plastic dowel clamps, simply called “herringbone”.
  • Apply a small amount of sealant to the end of the corrugation, from which the temperature sensor is placed. This is done to protect the sensor from penetration of concrete mortar.

The use of a bellows is mandatory, as it simplifies the replacement of the temperature sensor in case of failure.

Installing the heating element

After the above steps to prepare the work surface and install a thermal insulating layer with a metal mesh, you can begin laying the heating element whether it is a cable teplûks or electric.

Important! Before laying and fixing the heating element, check its internal resistance using a standard multimeter. Nominal values are specified in the manufacturer’s passport for the product.

If there are no internal resistance values in the passport, they should be recorded by yourself after the measurements. This will help us to know if the system is in good working order in the future.

Installing electric cable

If the cable or heating mats are in good condition, you can proceed with installation on the floor heating.

  • When using cable, it should be stretched across the entire surface in even zigzags. The electric cable is coiled in a convenient coil, from which it can be immediately mounted on the metal mesh.
  • After each turn, the cable is attached to the metal mesh with cable ties every 15-20 cm.
  • The distance between the coils: at least 100 mm.
  • Side coils should be located at least 150 mm from the wall.
  • The most common way of laying. “serpentine”, but some home masters prefer “spiral” or “snail. It should be clarified immediately that the choice of pattern is available only when installing electric cable. the boards are laid straight and perpendicular, equally butt to butt.

Do not overtighten the cable with cable ties. This can lead to damage to its insulation and rapid failure, immediately after pouring the construction under the tiles with your own hands. It is sufficient to simply tighten the plastic clamp, and after feeling the first effort. leave it.

Installation of electric mats

Installation of heating mats is faster than cables. This is aided by a convenient, ready-to-use design in which the heating element is already attached to a fine mesh. The installation is performed in 3 steps:

  • Unrolling the roll over the entire area of the room.
  • Fixing strips with mats to each other using construction adhesive tape.
  • Check the resistance and connect the system to the power grid.

In order to avoid sudden breakdowns, it is necessary to minimize movement on the mats laid out and fastened to the concrete base. Improper movement leads to damage to the heating elements, after which entire sections fail.

Screed pouring and tile laying

Once the electrical part of the system is ready for connection and further operation, you can start pouring concrete mortar on the floor heating.

Some guidelines for installing electric flooring advise making the thickness of the screed for heating cable. not less than 50 mm, and for mats. not less than 30 mm. But you can add these readings, and with both types of heating elements do screed 50 mm, so that you can then easily lay tile or tile. With proper insulation this will be quite enough.

Advice! When installing an electric floor, it is better not to use concrete mortar, but a special tile adhesive mixture. Pros: dries faster and does not reduce the height of the room.

How to lay an adhesive screed correctly:

  • Prepare the mortar by mixing all the ingredients in the proportions indicated on the package. It is necessary to carefully monitor the amount of water, as too liquid solution will not lay the tiles.
  • Apply a small amount of mortar to the warm floor with a special trowel with shaped edges. Then stretch the mixture so that it covers the heating elements. The thickness of the electric floor heating under the tiles, even when laying cable will not be too noticeable in relation to the overall height of the room.
  • Apply layer after layer until the thickness of the screed is 50 mm. Careful attention to avoid air s and air s.
  • Try not to catch the cable or mats under the tile with a putty knife. its edges are sharp enough and you can damage the insulation unnoticeably.
  • Exactly one day after laying tiles it is possible to grout joints. Turn on the system to test the performance is allowed at least 3-5 days after the final drying of the adhesive solution.

The use of a trowel is a must, otherwise the tile or tile can fall off after a few months of use. It is best to lay tiles at a time, as a properly prepared mortar quickly dries up.

Electric underfloor heating under tiles: laying and installation with your own hands

Underfloor heating. one of the undoubted advantages for both apartments and private homes. One problem. usually the floor is not happy with heat, especially concrete. Of course, a floor covering can soften the unpleasant impression, smooth out the coldness of the floor. But a more rational option. to arrange a water or electric “warm floor” under the tile or laminate.

Is it possible to lay a heating cable under the tile

For cold tiled rooms, electric floors are better. Heating cables or mats provide fast and even surface heating, have good heat transfer characteristics, and are completely safe in use.

The device of electric cable underfloor heating under tiles is the best option for heating: bathrooms, hallways, baths and saunas, balconies and loggias, sidewalks, etc.п.

The heating system has several major advantages over water and infrared flooring:

    Electric floor thickness. The heating cable must be installed in the screed. According to the manufacturer’s manual, the minimum thickness of the floor can be between 3-5 cm. Mats are placed directly under the tiles, so they reduce the height of ceilings by only 0.5 cm.

Ceramic and any other tiles have good heat dissipation characteristics. As a result, the optimum temperature in the room is easily achieved, overheating of the cable is excluded, which leads to a significantly longer service life.

| Denial of responsibility | Contacts |RSS