Electric underfloor heating: power per square meter

The warm floor appeared relatively recently and quickly became popular. Its main indicator is the consumption of energy, which depends primarily on the destination. If the floor is the main heater, the power will be 180-200 W / m ² , if the additional one - 100-160 W / m ² .

With any heating, including when using a warm floor, the power is most used for warming up. In the stationary mode of heating, the energy parameters are only supported and it is required less. Under favorable conditions, the floor can only be switched on for 15 minutes per hour. For a day it will be only 6 hours.

Power consumption in the house

Energy consumption is affected by the following factors:

• The higher the thermal insulation of the premises, the less energy is spent on heating;
• In the cold, the electric floor is switched on much more often;
• The power of heaters is required more with an increase in the thickness of the screed;
• Each person perceives the temperature differently: for some, more heating is required, for others, less;
• The presence of programmable thermostats reduces the energy consumption when properly tuned.

Types of heaters

For heating of premises are used:

• heating cable;
• Thermometers;
• Infrared devices (film or rods).

The cable is laid in the screed or the adhesive layer of the ceramic masonry. The film can be placed in an adhesive layer, under a laminate or linoleum. As a rule, it is used for thin flooring. Each method of heating has features, but it is common for everyone to heat from below, which requires 15% less energy. Radiators do not heat the bottom of the room. That there was heat, it is necessary to submit on them a coolant with a higher heating temperature.

Which gender?

The warm floor can be water or electric at the master's discretion. The first option is allowed to be used in private homes, since its connection to a centralized heating system is prohibited. For your house, the water floor is preferable, because the use of electricity for heating costs more.

In flats of high-rise buildings it is preferable to use electric warm floor. Power can be selected small, since floor heating is optional, and radiator - the main one. The type of heater depends on which coating is used.

Heating cable

Due to the low cost of the cable laid in the screed, many prefer to use it. The thickness of the concrete is about 5 cm. With its increase, heat losses increase. To make the screed thinner, use reinforcement or self-leveling floors.

The simplest and cheapest cable is resistive. It is manufactured single-core and double-core. The latter is more convenient to use, since the reverse end does not need to be brought back to the thermostat. In this case, the counter-current of the electric current in the adjacent wires mutually compensates for the interference.

The power of the cable is small, but it can be increased to 200 W / m ² with a tight laying of turns on each square meter.

Heat throughout the wire surface is released evenly. If you put furniture or put a carpet in a certain place on top, there may be overheating due to the deterioration of heat transfer. This lack is devoid of a self-regulating cable, in which the resistance depends on the temperature. The current flows in the transverse direction through the conductive layer from one conductor to the other, passing with it in parallel.

However, the laying of a warm floor under household appliances or furniture is an irrational solution. The heating of the room depends on the capacity of the warm floor in it. If there are obstacles to the return of heat, it may not be enough.

The warm floor is usually laid in places where furniture and household appliances are not supposed to be installed. As the main heating it is effective if it occupies not less than 70% of the area of the room. When the room is strongly forced, it is advisable to use radiator heating. Under additional heating it is enough to use not less than 30%. Apply also a comfortable mode, when it is important that the floor is not cold.

Cable mats

A thin heating cable is made fixed on a flexible grid. The advantage lies in the small thickness of the cable mat. In addition, there is no need for its laying on the floor by a snake. It is enough to spread the mat over the floor and connect the power to it. The cable mat is placed even in the layer of tile adhesive. The screed with the coating heats up faster, due to its small thickness.

The design of the cable mat is improved. Products with a heat-insulating layer and a strong coating have now been manufactured. The warm floor spreads on a flat surface and a board or laminate is laid on top without a screed.

Infrared film

Carbon film roll heater is an innovative solution. The film thickness does not exceed 3 mm. Heating occurs by infrared radiation, which makes it possible to increase the efficiency up to 95%. Therefore, the power of the infrared warm floor is consumed more economically. This heater is suitable for any coating.

In addition to the film, thermometers are produced with carbon-fiber heating rods operating in the same way. It is laid under the floor covering. If a screed is used, the thermowell is protected with a polyethylene film.

The thickness of the film warm floor is 110-220 W / m ² , the core - 70-160 W / m ² .

Electro-water heating

A new system has been developed that does not need boilers, pumps and a manifold system. A heating cable is inserted into the polyethylene tube filled with antifreeze along the entire length. When switched on, the coolant heats up and boils. As a result, the efficiency of heating increases.

Electro-water floor can be left in the apartment unattended, thanks to high reliability and safety. The large inertia of the screed allows switching to another room when one room is heated.

Calculation of energy consumption in one room

For an area of an average room of 14 m ^2, enough to heat 70% of the surface, which is 10 m ² . The average thickness of the warm floor is 150 W / m ² . Then the energy consumption for the whole floor is 150 ∙ 10 = 1500 W. With an optimal daily energy consumption for 6 hours, the monthly electricity consumption will be 6 ∙ 1.5 ∙ 30 = 270 kW ∙ hour. At a cost of kilowatt-hour 2,5 r. The costs will be 270 ∙ 2.5 = 675 r. This amount is spent at constant round-the-clock operation of the underfloor heating. When installing the thermostat to a programmable economy mode with a decrease in the intensity of heating in the absence of owners in the house, the energy consumption can be reduced by 30-40%.

Your calculation can be checked using the online calculator.

Calculation of the power of the warm floor is done with a small margin. In addition, it depends on the type of room. The actual average annual calculation will be less, since heating is switched off in a warm time (late spring, summer and early autumn).

You can check the real energy consumption with the help of the meter, when other electrical appliances are switched off.

The thickness of the water-heated floors is more difficult to calculate. It is better to use the on-line calculator Audytor CO.

Heating power in different rooms

When the floor is installed in different rooms, the power in each of them must differ depending on the functional purpose. Maximum heating is needed for balconies and glazed loggias. Comfortable conditions are achieved at a power of 180 W / m ² . In this case, the premises must be carefully insulated and all cracks are embedded in them. The power consumption of the warm floor on the balcony or loggia will be small, since there is no need for constant switching on.

Bedroom, kitchen, living room require a small level - 120 W / m ² . In the nursery, bathroom and rooms, where there are no heated rooms from below, the capacity of the warm floor should be about 140 W / m ² .

Different coatings require their own heating conditions. Linoleum and laminate can be heated with a warm floor, the power of which should not exceed 100-130 W / m ² . When it is used as an additional heater, the recommended power is 110-140 W / m ² .

Taking into account the requirements of all tenants and the influence of weather conditions, floor heating should be taken with a margin. In addition, in almost every room are installed heat regulators, with which you can set the desired heating mode. Heating works efficiently and without accidents, when it is loaded no more than 70% of maximum capacity.

Conclusion

With a proper design, the underfloor heating system ensures the economical use of electricity, while creating a comfortable environment in the house. To get the effect, it is necessary to correctly calculate the heaters and to select the controls. Energy costs also depend on the proper operation of the heating system. It is necessary to install a programmable regulator on a warm floor, the power of which is determined by the switching on time, the type of room and other factors.