Why do we make underfloor heating? For what purpose? When choosing a heating system, we naturally think about the efficiency of heating in the first place. However, in the case of underfloor heating, in addition to efficiency, comfort comes to the fore. A warm water floor was originally invented in order to increase the level of comfort in a living space, not as the main heating system. Accordingly, homeowners have always had a question. What should be the coating for a warm water floor in order to have effective heating and ensure the aesthetics of the interior.
Since time, consumers have appreciated all the advantages of this method of heating interior spaces. The practical use of underfloor heating in a variety of ways gives an idea of how different floor coverings behave in a given situation. Thanks to modern technologies, today the consumer has at his disposal a fairly wide selection of materials that can be used as a coating for a water floor. What types of coatings can be used in this case, what are their technological parameters and operational capabilities? In this article we will try to answer these and other questions.
General information about warm water floors
Traditionally, it is customary to use water heating systems at home. Water heated in an autonomous boiler or a heat carrier coming from a centralized central heating main diverges through the pipeline, supplying heat to heating devices. In the past, radiators were the main source of space heating. With the correct connection of the batteries and the absence of air pockets, this heating option is quite effective. The minimum amount of consumables and auxiliary equipment makes the installation of such a heating system convenient and affordable. Captivating and the cost of this option.
With warm floors, the situation looks different.
As a result of heating the coolant, the water circuit laid inside the floor distributes thermal energy over the entire area of the heated room. There is a natural process of transferring thermal energy to the lower layers of air in a heated room. Further, under the influence of the laws of thermodynamics, the circulation of air masses occurs, warm air rises, while cool air cools down. And this happens all the time, all the time.
This method of heating allows you to create an optimal temperature regime inside the living space, thereby increasing the level of comfort. Unlike radiators, which mainly work as a thermal curtain, a heated floor supplies heat to the entire interior space.
For reference: just look at the sanitary standards specified in the SNIPs. In accordance with the norms, the surface temperature of the floor should not exceed 290C, and the coolant should not have a temperature above 550FROM.
The heated floor surface plays the role of a heating device with a large heating surface. The efficiency of such a system depends not only on the functionality of the entire heating complex, but also on what kind of floor covering is used to equip the water-heated floor. Initially, heat is transferred from the water circuit to the concrete screed or stacked structure, and only then, by heating the floor covering, the heat is transferred to the nearby air layers. The table shows the technological values for various materials used as flooring.
In homes and in residential areas in general, underfloor heating is very convenient. In addition to the original and effective way of heating, underfloor heating opens up wide opportunities for designers to work with the interior of a living space. Normal operation of heating equipment is only half the battle. A number of factors are important. How the concrete screed of the heating floors is made, how the wooden floor is laid and what kind of floor finishing material is used. We often select flooring for aesthetic reasons, with little regard for how pleasant the floor surface is to the touch. When choosing a finishing material for the floor in your home, you need to take into account how the coating will interact with the heating system.
What coatings can be used today when equipping underfloor heating systems in an apartment or in a house.
Types of floor coverings and their thermal conductivity
In order for the warm floor in your house to please you, work for a long time and with maximum benefit, you need to choose the right floor covering. Finishing work in this case is crucial, since the mistakes made can neutralize all the advantages of a warm floor.
Materials for finishing floors produced today by manufacturers can be used as a coating for your warm floor. It doesn’t really matter what material is used. Most floor coverings are practically compatible with underfloor heating. Differences can be in the structure of the base material and the thermal conductivity of the coating, which naturally affects the quality of the heating system.
Today, the following types of floor coverings are used for equipment underfloor heating:
From natural raw materials:
- parquet board;
- industrial, technical parquet;
- wooden boards (oak, beech, ash);
- ceramic tile;
- porcelain stoneware;
All of the listed types of coatings and materials are available to the consumer. Only the price differs. In accordance with the physical properties and performance characteristics, the scope of each type is also determined. For living rooms, parquet, wooden board and laminate are perfect. For domestic premises where high humidity is observed and sanitary standards are required, linoleum, ceramic tiles and natural stone can be used.
Different areas of use and operating conditions determine the effectiveness of underfloor heating. However, the decisive factor for the operation of the “warm floor” heating system is the thermal conductivity of materials. The figure shows the thermal conductivity of all floor coverings used today in everyday life, which can be used in combination with hot water floors.
Ceramic tile. Coatings made of natural and artificial stone
In terms of thermal conductivity, one of the first places is occupied by ceramic tiles and other coatings made of natural or artificial stone. An example of the high efficiency of such floor coverings is the concrete screed itself. Yes, the concrete floor will have to be heated for a long time, but then, the concrete will keep the heat perfectly, giving part of it inside the heated room. The same principle applies to ceramic tiles.
For reference: Warm ceramic tiles are ideal flooring for bathrooms, saunas and baths. In rooms with high humidity, tiled floors not only create additional comfort and coziness, but also perform an important sanitary function. Fast drying of the floor surface prevents the formation of mold and other pathogens.
Here it is important to take into account not only the good thermal conductivity of ceramic tiles and porcelain stoneware, but also their high heat capacity. For normal heating, you will need a powerful boiler and a certain layout of the water circuit. Properly selected step of laying the underfloor heating pipe will ensure uniform and stable heating of the entire surface of the concrete-ceramic floor.
Laminate and wood flooring
The most popular floor covering for residential, inhabited premises is laminate. Today, this material is very popular. Bribing high aesthetic characteristics of the laminate, its practicality in operation and a simple way of laying. Moreover, the laminate is an order of magnitude cheaper than a parquet board, although outwardly it is not much inferior to the original wooden coating.
Thanks to the manufacturing technology, the laminate has a dense structure, which naturally has a positive effect on the thermal conductivity of the material. Laminate flooring looks beautiful and harmonious in living spaces and, if installed correctly, can satisfy you in every aspect.
Important! Laminate flooring must only be laid on a dry concrete screed. Otherwise, the bottom surface of the material will absorb the remaining moisture, which will ultimately lead to disastrous results. As the laminate tile dries, it will begin to change its physical properties and shape. The coating will begin to “walk”, creak and deform.
For laminate, the permissible heating temperature of the warm floor is 270C. This temperature is very comfortable for the human foot and has a positive effect on the condition of the flooring.
Using underfloor heating in combination with a wooden board is not the best option. Natural wood has a low thermal conductivity, so the efficiency of the water floor in such a room will be extremely low. Under the influence of heat, the boards dry out faster, which naturally affects the strength of the floor and its aesthetic characteristics. Similarly, we can summarize the behavior of parquet in combination with underfloor heating. The expensive and luxurious appearance that the parquet gives to the interior decoration of the room will become an obstacle to the normal heating of the interior space.
The linoleum that is familiar to all of us, along with water floors, does not behave in the best way. In practice, it has been noticed more than once. Different types of linoleum behave differently in combination with a heating floor, although some types cope with the tasks. Which? Linoleum without insulation, on a smooth basis, has the necessary thermal conductivity, is resistant to heating and retains its shape for a long time.
On a note: use linoleum without felt insulation and PVC foam. For a warm floor covered with thin linoleum, the optimum heating temperature is no more than 270C. Otherwise, under the influence of high temperature, linoleum may change color, become excessively soft and lose its shape.
It is strongly not recommended to use vinyl or PVC tiles for underfloor heating. These materials have a high coefficient of thermal linear expansion (CTLE), which negatively affects their behavior at the time of heating. Remember the option with polymer pipes used in the communications system.
The most unsuitable material for water heated floors is carpet. The material completely extinguishes the heat coming from below, preventing the main action of the heating system.
Marking of floor coverings used for underfloor heating
Like any finishing and building material, floor coverings must be appropriately marked.
Each material must have appropriate icons, symbols and pictograms indicating that this type of coating can be used in combination with water underfloor heating. Pay special attention to the laminate. It is based on formaldehyde, a chemical element that is harmful in high concentrations. According to the values on the E0-E3 marking, one can judge the permissible norms for the content of formaldehyde in the material. For a warm floor, the ideal value would be E0 or E1.
Tiles and porcelain tiles also have a marking indicating the scope of use. For underfloor heating, such materials usually have a smaller thickness, which accordingly affects the degree of heating.
In conclusion, I would like to say. If you have a warm water floor as your main heating option, then try to combine ceramic tiles and laminate flooring. Other flooring materials are ineffective, and in some cases useless.