Warm floors appeared relatively recently and quickly became popular. Its main indicator is energy consumption, which depends primarily on the destination. If the underfloor heating is the main heater, the power will be 180-200 W / m 2 , if additional - 100-160 W / m 2 .
For any heating, including when a warm floor is used, the power is most spent on heating. In stationary heating mode, energy parameters are only supported and less is required. Under favorable conditions, the underfloor heating can only be switched on for 15 minutes per hour. For a day it will be only 6 hours.
Home energy consumption
The following factors affect energy consumption:
- the higher the thermal insulation of the premises, the less energy is spent on heating;
- in cold weather, the electric floor turns on much more often;
- the power of the heaters is required more with increasing 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 energy consumption when properly configured.
Types of Heaters
For space heating are used:
- heating cable;
- thermomats;
- infrared devices (film or rods).
The cable is laid in a screed or adhesive layer of ceramic masonry. The film can be placed in the adhesive layer, under the laminate or linoleum. As a rule, it is used for thin flooring. Each heating method has features, but common to all is heating from below, which requires 15% less energy consumption. Radiators do not heat the lower part of the room. To keep it warm, a coolant with a higher heating temperature should be supplied to them.
Which gender to choose?
Underfloor heating can be water or electric at the discretion of the owner. The first option is allowed to be used in private houses, since its connection to a centralized heating system is prohibited. For your home, a water floor is preferable, since the use of electricity for heating is more expensive.
In apartments of high-rise buildings, it is preferable to use an electric heated floor. You can choose a small power, since floor heating is optional, and radiator heating is the main one. The choice of heater type 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 concrete is about 5 cm. With its increase, heat loss increases. To make the screed thinner, use reinforcement or self-leveling floors.
The simplest and cheapest cable is resistive. It is available in single-core and two-core. The latter is more convenient to use, since the return end does not need to be fed back to the thermostat. In this case, the countercurrent flow of electric current in neighboring conductors mutually compensates for interference.
The power of the cable is small, but it can be increased up to 200 W / m 2 with tight laying with turns on each square meter.
Heat is distributed evenly over the entire surface of the wire. If furniture is placed on top of a certain place or carpet is laid, overheating may occur due to poor heat transfer. This self-regulating cable is deprived of this drawback , in which the resistance depends on temperature. The current flows in the transverse direction through the electrically conductive layer from one conductor to another, passing in parallel with it.
However, laying a warm floor under household appliances or furniture is an irrational solution. Space heating depends on how much heat the floor has in it. If there are obstacles in the transfer of heat, it may not be enough.
Underfloor heating is usually laid in places where it is not intended to install furniture and household appliances. As the main heating, it is effective if it occupies at least 70% of the room area. When the room is heavily crowded, it is advisable to use radiator heating. For additional heating, it is enough to use at least 30%. Comfort mode is also used when it is important that the floor is not cold.
Cable mats
Thin heating cable is produced mounted on a flexible grid. The advantage is the small thickness of the cable mat. In addition, there is no need for laying it on the floor with a snake. It is enough to spread the mat on the floor and connect power to it. The cable mat is even placed in a layer of tile adhesive. The coated screed heats up faster due to its small thickness.
The design of the cable mat is being improved. Now products with a heat-insulating layer and a durable coating have begun to be produced. The warm floor is spread on a flat surface and a board or laminate is laid on top without screed.
Infrared film
The carbon film roll heater is an innovative solution. 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. Such a heater is suitable for any coating.
In addition to the film, thermomats with carbonic heating rods are produced, working on the same principle. It is laid under the floor covering. If a screed is used, the thermomat is protected with plastic wrap.
The power of the film heat-insulated 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 manifold systems. A heating cable is inserted along the entire length into a polyethylene tube filled with antifreeze. When you turn on the coolant heats up and boils. The result is increased heating efficiency.
The electro-water floor can be left unattended in the apartment due to its high reliability and safety. The large inertia of the screed allows you to switch to another room when one room is heated.
Calculation of energy consumption in one room
For an average room size of 14 m 2 , it is enough to heat 70% of the surface, which is 10 m 2 . The average power of the warm floor is 150 W / m 2 . Then the energy consumption for the entire floor will be 150 ∙ 10 = 1500 watts. With an optimal daily energy consumption of 6 hours, the monthly energy consumption will be 6 ∙ 1.5 ∙ 30 = 270 kW ∙ hour. At the cost of a kilowatt-hour 2.5 p. costs will be 270 ∙ 2.5 = 675 p. This amount is spent with constant round-the-clock operation of the warm floor. When the thermostat is set to programmable economy mode with a decrease in the intensity of heating in the absence of owners in the house, energy consumption can be reduced by 30-40%.
You can check your calculation 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 the heating is turned off in the warm time (in late spring, summer and early autumn).
You can check the actual energy consumption with the help of a meter when the rest of the electrical appliances are turned off.
The power of water heated floors is more difficult to calculate. It is better to use the online calculator Audytor CO.
Heating power in different rooms
When a warm floor is installed in different rooms, the power in each of them should differ depending on the functional purpose. Maximum heating is needed for balconies and glazed loggias. Comfortable conditions are achieved with a power of 180 W / m 2 . At the same time, the rooms must be carefully insulated and all the cracks are closed in them. The power consumption of the underfloor heating on the balcony or loggia will be small, since there is no need for constant switching on.
The bedroom, kitchen, living room require a small level - 120 W / m 2 . In the nursery, bathroom and rooms where there are no heated rooms below, the power of the underfloor heating 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 used as an additional heater, the recommended power is 110-140 W / m 2 .
Taking into account the requirements of all residents and the influence of weather conditions, floor heating should be taken with a margin. In addition, heat regulators are installed in almost every room, 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 power.
Conclusion
With proper design, the underfloor heating system ensures the economical use of electricity, while creating comfortable conditions in the house. To get the effect, you need to correctly make the calculations of the heaters and select the controls. Energy costs also depend on the proper operation of the heating system. You should install a programmable controller on a warm floor, the power of which is determined by the turn-on time, type of room and other factors.