Infrared underfloor heating under tiles: peculiarities of installation
The installation of infrared flooring under the tiles is not as difficult as it may seem at first glance. But there are a few nuances that are important to consider. To begin with it is necessary to worry about the materials and tools that you may need for work. It can be a heat-reflective substrate, the IR film itself in the required quantity, tape for wire insulation, tile and glue for it, duct tape, corrugated tube, drywall, contact clips, polyethylene, wires for connection, scissors, etc. д.
Both the tile and the IR heating system need a level base for installation. Therefore, it must be cleaned of debris and inspected for damage, protrusions. There should not be any relief on it. all cracks are sealed, and it is recommended to grind away the bulges.
Also included in the preliminary works of installing the infrared floor system is the creation of a scheme for laying the infrared film and the placement of various elements such as the temperature regulator. It should take into account the location of large furniture, and places where the film will not be installed. It is important to remember, that all wires, going from heating system to a thermostat, should be laid in a corrugation and a groove, punched in a wall. However, it is not always necessary to make a hole in the wall. Sometimes wires are installed in a narrow plastic channel that is fastened to the surface of the wall.
Attention! Work with infrared heating film is important to be careful, because it is quite easy to damage. And cut it only along the clearly marked cut lines. If you cut the foil elsewhere, it can be destroyed.
How to cut the infrared heating foil
All installation work must be carried out at temperatures above 0 degrees and humidity of no more than 60%. It is also important to ground the entire system. Particular attention is paid to the insulation of contacts, as well as possible places of damage to the film.
Table. Types of IR film installation.
How to lay an electric underfloor heating under the tile?
Heating and keeping the living space warm is a matter of vital importance. The floor surface of the kitchen, bathroom, bathroom or hallway is most often cool ceramic flooring. In summer this factor can be pleasant, but in winter the cold floor becomes a problem, especially for families with small children. Electric underfloor heating under the tiles is an acceptable method of solving this issue. Independently install heated floors is not difficult, if you know the basic techniques of how to install under the tile heating elements.
Step by step installation technology
Now let’s consider how to properly make a warm floor under the tile with your own hands.
Preparation of the room and the base includes the following steps:
- At the place of installation of the temperature sensor with the help of a diamond drill a hole is made for a socket.
- For laying the power cable from the switchboard, depending on the chosen method of laying, grooves are cut or a cable duct is installed. For safety reasons, the thermostat must not be located in a wet room. it is mounted through a partition in another room. For convenient connection of wires to the temperature controller it is better to install a deep under-socket.
After all the preparatory work, proceed to the preparation of the base:
- Remove construction debris, fill large cracks, chips and other defects.
- For height differences from 2 cm to 1 meter, the foundation is leveled with a thin cement screed or self-levelling mixture.
- Lay a layer of polystyrene boards with a thickness of 20 to 50 mm, so that the heat does not go into the floor slab (this point varies depending on conditions).
One way to make a marking is to use colored adhesive tape, but a simple marker or a pencil will do.
Waterproofing over insulation in this case is needed only to prevent the fluid from the mortar flowed to the neighbors from below and spoil their repairs. If you have no neighbors, or they have not yet repairs, or you reliably sealed all the cracks, you can not do waterproofing.
Installing the heating cable
On the base are laid and fastened with self-tapping screws or dowels mounting strips, which are necessary to fix the coils of cable.
Before installing the heating cable you need to check its integrity by measuring its resistance with a multimeter. If the value obtained falls within the range specified in the certificate, the integrity of the cable is not violated and it is suitable for laying.
Then the cable is placed on the surface of the floor with loops or a snake and fixed with bending tendons on the mounting bar. Laying begins from the hole in the wall leading to the mounting box and estimate the required length of the cold end for connection. To avoid a crossing of the cold end with the heating part, the laying usually starts along the wall.
Note! Prefabricated heat mats on a mesh base are much easier to install: most often they have an adhesive backing, which allows the mats to be easily fixed to any base. If it is necessary to turn, the mesh base is trimmed and the cable is smoothly turned at the desired angle, without twisting or kinking.
After laying the cable, the cold end is led into a socket mounted for installation of the thermostat, the ends of the wire are stripped and marked with the letters TP, indicating the phases (N and L) for further connection.
The next step is the installation of the temperature sensor, which is done in this sequence:
- From the socket is laid corrugated pipe. Its free end is placed between the coils of the heating cable at the same distance and closed with a plug to prevent the mortar from getting into it when pouring the screed.
- Thermo sensor is inserted into the pipe, the cable ends are stripped and marked (DT) for connection.
Important! After installing the heating cable, measure the resistance again to make sure there is no damage. If the values remain at the same level, proceed to the next stages of installation of the floor heating.
After laying the heating cable and the temperature sensor the cable is covered with a self-levelling compound designed for use in underfloor heating systems. The layer of the filler is enough to completely cover the cable, taking into account the possible shrinkage of the screed. Tile laying on the cement screed is made not earlier than 3-7 days, and on the self-levelling mixture. according to the manufacturer’s recommendations.
Along the pre-prepared grommet from the switchboard to the socket, the power cable is laid. The cross-section of the wire laid should be sufficient to bear the connected load. In the mounting box, strip the ends of the wire and mark them with the letters N and L. Circuit breaker selected based on the cross section of the cable, usually using a cable cross section of 2.5 mm ² and a circuit breaker for 16A.
Note! If the heating cable is equipped with a screen, a three-core cable must be installed with the ground core connected to the screen of the heating element.
Connect to the thermostat according to the marking:
- The power cable strands are connected to the terminals marked L and N, observing the polarity.
- Heating cable strands are also connected according to the marking and polarity: Ltp to terminal L1, and Ntp to terminal N1.
- The core wires of the temperature sensor are connected to the corresponding terminals on the temperature controller marked SENSOR or marked with a t°C symbol.
After all wires are connected, the thermostat is installed into a socket and fixed with screws. This completes the installation of the floor heating.
Take note! Start-up of underfloor heating 28 days after screed filling. It is recommended to switch it on for the first time at minimum power, and then gradually (once a day) increase the temperature by 5 °C.
The standard heating mat set consists of two elements:
- Thermo mat in a roll with a power cable.
- A duct with a metal probe and a plug for the attachment of a temperature sensor. It is needed to protect the sensor from alkali and moisture. If the layer of tile adhesive does not allow installing a corrugator, you can buy a special moisture-proof sensor.
- Thermostat. Selected on the basis of the maximum power consumption.
- Mounting boxes if the thermostat is to be installed in the wall.
- Remote temperature sensor (usually comes with the thermostat). It is better to take a contact sensor, not the one that will measure the air temperature.
- Wires to connect the thermostat to the mains. The cross-sectional area must be selected according to the rating of the system and the conductor material (see the table below). according to the table below)
The connection must always be made through a thermostat to maintain the set temperature.
According to the Rules for Electrical Installation (PUE) must install RCD (ground fault interrupter) with a current of 30 mA, 100 ms and circuit breaker max 10 A (type C). Systems over 2 kW are recommended to be wired through a separate circuit breaker.
If you are installing in a bathroom or other humid area, the thermostat must be located in an adjacent dry room.
The cable must not be shortened or cut! If necessary, you can cut off only the supply wire.
The photo shows possible installation schemes for the existing flooring or conventional screed
The sequence of installation
Determine where to place the thermostat on the wall and where the thermo mat will lie. Over the floor heating must not be a furniture without high legs, plumbing or household appliances. If there are damping seams on the screed, the mat should not go through them. Use a separate thermo regulator and mats for each room. If the room is planned to do a few finishing coats with different properties, you need to put a separate thermostat under each of them.
Install the standard temperature sensor inside the corrugated tube. To prevent it from creating additional unevenness, a grommet is made in the floor and wall for it. The end of the corrugated tube is closed with a stopper to prevent mortar from getting inside. The end of the sensor should be installed with an indent of 50-100 cm from the wall slightly below the mat, in the center between the two coils of the cable. Do not make corrugations with a radius of less than 5 cm, so that you can replace the sensor.
Before installing the heating mat, you need to cover the concrete floor with a primer, to dedust the surface and increase the adhesion of the tile adhesive.
Place the heating mats on the selected heating zone. To get the desired shape, you can cut the mesh and wrap the cable, but you can not cut it. The grid is attached to the floor with tape or staples, cable upwards.
After laying the cable, you need to measure the ohmic resistance with a multimeter. It must be within the range (plus or minus 10%) that is written in the manual or the manufacturer’s warranty card.
Connect and install the thermostat
Strip 5-7 mm of insulation at the lead-out of the installation wires from the mat and the 220V power supply wire.
Connect the wires to the terminals on the thermostat, following the wiring diagram in the manual.
The cable shielding must be connected directly to ground.
Installation can be done immediately on the tile adhesive, or pre-pour the mats with screed (at least 2 cm thick). It is forbidden to lay tiles on a substrate of chipboard, plywood or other material.
- Apply the tile adhesive directly onto the mat. In wet areas (such as bathrooms), first apply a thin layer of adhesive to the mats. After it hardens, apply the waterproofing and the second layer of adhesive.
- It is desirable to use special adhesive mixtures for warm floors, they are more elastic.
- Spread the adhesive evenly with a toothed trowel. For this case, it is recommended to use only plastic combs, so as not to damage the cable.
- Press the tiles or porcelain tiles onto the adhesive, making sure they are level. The thickness of tile adhesive along with the tiles should be at least 2 cm. Some manufacturers (e.g. DEVI) recommend a covering layer of at least 5 cm. This is due to the fact that with such a layer, the heat will be distributed evenly.
Creating a pattern
Before starting the installation it is very important to calculate everything correctly. For this purpose, a connection diagram of the electric floor heating. Here is a must to indicate the step of laying electrical wiring or heating mat. In any case, you should follow certain recommendations to get a really good scheme:
When choosing the step of laying an electric underfloor heating under the tiles, you should maintain a distance from the walls in the room, which will be at least 100 mm.
Detailed installation diagram
Above we have considered a brief algorithm for the installation of underfloor heating. Let us now look at the installation in more detail. For convenience, we have divided the installation into stages, which will help you to remember the material easier.
Preparation of the circuit diagram and auxiliary works
First it is necessary to make an approximate installation diagram of electrical equipment. In the case of mats, it is simple enough just to estimate how approximately they will be located along the length and width. If you use wires, you need to decide on the scheme of their location optimal schemes will be a snake or snail. At this stage it is also recommended to determine the location of the thermostat, since its position will determine the construction of the whole system.
Selection of all necessary materials and equipment
Now you need to go to the store and buy the following equipment:
- Wires or mats.
- Additional wiring to connect to the thermostat.
- Thermostat and temperature sensor.
- Tapes (foil or polyethylene foam).
- Tiles and glue for it.
- Grounding copper cable.
Please note! It is also recommended to buy an emergency power disconnect device, which will turn off the heating in case of power surges (otherwise the wires and/or heating elements will quickly burn out).
Also, don’t forget to prepare the floor for installation. Optimal algorithm for action:
- First assess the nature of the floor. If there are many potholes or cracks, or the floor as a whole is very crooked, it is recommended to perform the pouring of concrete.
- If the damage is not too much, it will be enough to treat with putty (best option finish putty).
- After drying, clean the surface of debris and dust, and then apply a thick coat of primer (you can in two, although there is little practical use).
Thermal insulator and its installation
To reduce heat loss, after the primer dries, it is recommended to create a layer of thermal insulator, which will reflect the heat to the tile. As a material-insulator is recommended to use high-quality foil or a material called foamed foil. Glue the foil should be using a special adhesive, while the foil already has an adhesive surface on one side, which will greatly simplify its installation.
Install thermal insulator should be installed over the entire area, on which the heating elements will be mounted (best option on the entire floor). The insulator should also slightly cover the walls (5-6 cm), so the heat does not accumulate in the corners (a common mistake of beginners). Be sure to install an edge strip (damper) around the perimeter of the room. It will protect the heating elements from direct contact.
Why do you need a metal mesh and if you can do without it??
If your walls and floor are bad you can reinforce the surface with metal mesh. Prefer a thin-walled metal, which will not take up much space and will absorb heat to a minimum. The grid is placed across the entire floor, and a layer of polyethylene is laid on top with a slight overlap on the walls. It is recommended to glue the edges of the polyethylene to the wall to fix it securely.
Thermostat and temperature sensor as they are installed?
Now install the thermostat and temperature sensor. Note that these are two different parts that have different functions:
- The thermostat is attached to the wall next to the socket, or it is directly connected to the electric network. It is connected to the heating installation, and you need it to adjust its operation (eg to select the temperature).
- The sensor is placed on the floor (best option is mounted in a corrugated tube insulated from one edge in a groove). The sensor is connected to the thermostat with wires, and is needed to independently evaluate the operation of the system (in case the main thermostat fails).
Mounting the heaters on the floor
Now you can proceed to the installation of heating structures. The method of installation will depend on the technology used:
- Electric cables. As mentioned above, the cable is laid over the entire surface in two ways, snaking or snail-shaped. On the floor, the wires are very loose, so it is recommended to fix them with clamps or adhesive tape. Remember to connect the ends of the wires to the thermostat.
- Mats or film. These materials are attached very simply, they are rolled up on the surface and shifted to the right places as needed. The use of fasteners is not necessary in most cases, although you can secure them with duct tape if necessary. Attach the ends of the wiring to the thermostat according to the instructions.
It is also recommended that the unit be earthed to prevent the floor from becoming electrified should the cable become damaged. A thick copper cable is usually used for grounding, and many thermostats are equipped with a special unit that will act as an earth ground. If you don’t have such a hole, you can buy an earthing switch and connect the copper cable to it.
Pouring screed, laying tiles
If you used wires as the heating element, it is recommended to screed the floor with a mixture of sand (3 parts) and cement (1 part) upon completion of all work. The mixture is poured with water and stirred to the desired consistency. If the mixture is too liquid, you can add PVA glue to make it more adhesive. In the case of mats it is not necessary to screed, but you should put a layer of protective polyethylene.
After the screed dries, you can start laying tiles. To do this, cover part of the surface with glue and put ceramic tiles on it (do not forget to put plastic crosses, which will help to increase the strength of the construction). Gradually cover the entire surface with tiles, making sure to seal the seams. After 1-2 days, the seams will completely harden and you will get a fully functional underfloor heating made with your own hands.
Types of electric underfloor heating
In the construction store customers are offered several options for the electric floor:
- a heating cable, for the installation of which you will have to separately purchase the necessary fixing materials, thermostat, etc.п.;
- electric mats, which is a grid, on which the heating cable is already fixed;
- infrared systems, which work on a slightly different principle, but are installed in a similar way to a cable.
For a small area (bathroom floor, loggia, etc.).п.For a small area (bathroom floor, loggia, etc.) it makes sense to buy a complete turnkey system. Usually such sets are complete with everything you need for proper installation, sometimes even such trifles as corrugated pipe for the temperature sensor and double-sided adhesive tape.
Do not be guided only by the low price of the set, since the materials inside may be of poor quality. It is better to choose a set more expensive, but from a reliable manufacturer, such as Teplolux, Electrolux, Thermo, Devi, etc.п.
In addition to the kit is worth buying insulation, such as foil foam. It is laid under a warm floor to reduce heat loss and increase the efficiency of heating. When choosing a complete set for the installation of underfloor heating, you should be guided by the size of the installation area. The minimum size is one square meter.
If the floor heating is to be installed over a large area, it may be advisable to buy all the components separately. For such installation, an individual project is made and the components are purchased according to need.
In this way you can avoid unnecessary costs and choose elements that will work most effectively in the system. A distinction is made between single-core and double-core heating cables. The latter is somewhat more expensive, but it is considered to be safer.
Generally speaking, electric underfloor heating consists of the following parts:
It is worth knowing that the heating element will work without a sensor and thermostat, but the work will be inefficient and short-lived. Inefficient, because you have to turn it on / off manually, and this leads to overspending. And short-lived, because overheating often occurs during manual control, which negatively affects the service life of the heating element.
Components of electric underfloor heating
Types of heating elements
On the market you can be offered several different heaters:
Resistance heating cables. Have the lowest price, can be single and double wire, which changes the scheme of their connection. Their main drawback is the possibility of local overheating and failure (on the working resistive cable floor heating can not be put for a long time objects). Therefore, when installing cables do not lay out under places where there will be furniture and appliances. One more disadvantage long process of installation.
Which of these types of electrical floor is better, it is impossible to say unequivocally. Each has advantages and disadvantages, peculiarities of installation. Based on them choose the best option for a particular flooring under the tiles it is better to put cables or mats, and under the laminate or linoleum film heater.
Types of thermostats
There are three types of thermostats for electric floor heating:
- Mechanical. Similar in appearance and operating principle to the thermostat on the iron. There is a scale on which you set the desired temperature. As soon as it is 1°C lower than the preset temperature, the heating is switched on.
- Electro-mechanical. Functionally they are the same, but have a small LCD screen and up/down buttons. The screen shows the current temperature of the floor, and the buttons are used to adjust it in the right direction.
- Electronic programmable. The most expensive, but also the most functional. They can set the mode of operation (temperature) by hours, and in some models by days of the week. For example, if you all went out in the morning, you can set a low temperature of about 5-7 ° C, and an hour and a half before coming to program it to increase to a standard. There are some models with the ability to control over the Internet.
Some models of thermostats for underfloor heating have built-in air temperature sensors and the ability to turn the heating on/off according to these indicators, rather than depending on the floor temperature. So there really is a choice.
Installing electric underfloor heating under tiles
What is an electric underfloor heating
Electric underfloor heating. a cable heating system of increased reliability, which can be used as a system of comfort floor heating, and as the main heating system. The heating sections of underfloor heating systems are shielded single and double core cables with two layers of insulation, as well as reliable connection sleeves. Compared to traditional heating methods, where heat is transferred by convection currents, underfloor heating has a number of advantages:
- The heating part of the system is hidden in the floor structure, which allows you to increase the usable area and diversify the design of the premises, while the floor covering can be any: tile, marble, carpeting (except parquet).
- Does not dry out the air in the room because the heating cable is not in direct contact with the atmosphere.
- Double insulation and screened cable braid enables the use of underfloor heating in rooms with any moisture content.
First choose your system
Before installing underfloor heating we advise you to make sure you have selected the right system for your space and the type of heating you desire (comfort or basic).
Basic heating system in detached buildings, also in cases where there is no possibility to connect to the central heating system. the basic heating system requires the use of a more powerful cable and the installation of screed with a thickness of at least 5 cm. The floor heating area should be at least 70% of the total area of the room to be heated. Recommended power density of the system when using underfloor heating as the main heating system. from 160-180 W/m2. For example, a floor heating of 0.19kW, a heating area of 1.2m2; check the power: 190W/1.2m2 = 158W/m2.
Comfort heating system. Installed in conjunction with other types of heaters and designed to achieve thermal comfort. Most suitable for rooms with cold floors (bathrooms, toilets, kitchens, swimming pools) and on the first floors of buildings. Recommended power density of the system with comfortable floor heating 120-140 W/m2. E.g. floor heating of 0.19 kW, heating surface 1.5 m2; check the output: 190 W/1.5 m2 = 126 W/m2.
Check whether your space’s existing electrical installation allows for the connection of extra wiring. Consider additional electrical devices that can be connected to the same network. Please also specify the permissible current of the safety devices (circuit breakers). We recommend that heat tracing systems with a capacity of 2 kW or more be connected via special wiring and a separate fuse. We also recommend the use of RCDs with a rated operating current not exceeding 30 mA. This is a small device mounted on the electrical panel, which ensures the safety of the electrical insulation of your equipment. When underfloor heating is installed in wet areas (bathrooms, saunas, pools) the heating section screen must be connected to the mains earthing conductor, which in turn must be connected to all available metal parts such as: metal shower trays, metal shower frames, etc.п.
How to install underfloor heating and tile with large porcelain tiles
- Determine a free area without furniture and appliances.
- Separate from walls and furniture 5-10 cm.
- Choose a heating mat or section to the available space.
- The area of the heating mat or the heating surface of the section must not be larger than the available area.
- It is allowed to lay the floor heating under the furniture, if the height of the feet is not less than 15 cm.
The base of the floor heating is the heating cable. It looks like a radio-frequency cable for transmitting television signals, but its purpose is not to transmit electrical signals or power over a distance, but to convert all 100% of the power of the electrical current flowing through it into heat. This power release per unit length of cable (specific heat release) is the most important technical parameter of heating cables.
Binding core 2. Heat-resistant PVC plastic sheeting 3. Three protective layers PET 4. Heat resistant PVC plastic sheeting 5. Protective screen of copper tapes 6. Copper shield wire 7. PET 8. PVC laminate
Connection conductor 2. Return conductor 3. Heat-resistant PVC plastic sheeting 4. Three protective PET layers 5. Heat-resistant PVC plastic sheeting 6. Protective copper strip shield 7. Copper protective screen wire 8. PET 9. PVC plastic wrap
Subfloor base 2. Thermal insulation with foil 3. Heating section 4. Installation tape 5. Cement and sand screed 6. Decorative coating
Heating cores consist of a heating cable strip of a certain length and t.н. 4 “cold ends”. the segments of ordinary wire, connected to the heating cable with a muff. Sections can be made of single-core and double-core cable, and you should visually see at the ends: in single-core sections. two wires on each side (shield and load), in double-core sections. three wires on one side (shield, load, load).
where S is the area on which the floor heating is laid, L is the length of the cable section. The minimum paving distance is 8 cm
Underfloor heating on the basis of heating sections
Prepare a place in the wall for the installation of a thermo regulator. 2. Drill grooves in the wall for electrical wiring, heating section mounting ends and the tube for the temperature sensor.