Calculation of a water heated floor
Before installing and purchasing materials, be sure to make a floor heating calculation. To do this, draw a scheme with contours, which will then come in handy when carrying out repair work, to know the position of the pipes.
- If you are sure that in a certain place there will always be furniture or plumbing, in this place the pipes are not laid.
- The length of the circuit with a diameter of 16 mm should not exceed 100 m (maximum for 20 mm will be 120 m), otherwise the pressure in the system will be bad. Thus, each circuit approximately occupies no more than 15 sq. м.
- The difference between the lengths of several contours should be small (less than 15 m), i.e. they should all be of equal length. Large rooms, respectively, divided into several circuits.
- Optimal pipe spacing is 15 cm with good thermal insulation. If there are frequent frosts below freezing during the winter, our floor heating systems should be thoroughly tested in order to accurately calculate the required underfloor temperature.20, then the pitch is reduced to 10 cm (can only be at the outer walls). And in the north, you can’t do without additional radiators.
- If laying at 15 cm, pipe spacing is approx. 6.7 m per room square, if laid every 10 cm, pipe length is approx. 10 m.
In general, the question of how to calculate water underfloor heating requires a separate consideration, t. к. Many nuances are taken into account in the design: heat loss, power, etc. д.
The graph shows the dependency of the flow density on the average temperature of the heat carrier. Dotted line indicates a pipe diameter of 20 mm, and solid lines. 16 mm.
The graph shows data that are only valid when using cement-sand screed with a thickness of 7 cm, covered with tiles. If we increase the thickness of screed, for example, by 1 cm, the density of heat flow decreases by 5-8%.
- To calculate the heat flux density, the heat loss in watts of the room is divided by the pipe area (subtract the clearance from the wall).
- The average temperature is calculated as the average value at the inlet to the circuit and the outlet of the return.
The optimum inlet and outlet temperatures should not differ by more than 5 to 10 degrees. The maximum temperature of the heat carrier must not exceed 55 ° C.
To calculate the length of the circuit, the active heating area in square meters is divided by the pitch in meters. To this value, add the size of the creases and the distance to the manifold.

According to the given scheme, you can only make a rough calculation and make the final adjustment by means of a mixing unit and thermostats. For an accurate design it is necessary to contact a professional heating engineer.
Step of laying the pipes of the underfloor heating.
An important parameter is the pitch of the pipe. Its limits are from 10 to 60 cm. It depends on many factors:
- When laying the circuit in rooms with walls overlooking the street, make a step of 10 to 15 cm.
- In rooms without exterior walls, as well as in their central part do a step of 20 to 30 cm.
- In bathrooms, toilets, baths and other places where it is cool, the spacing should be 15 cm. over the entire area
Water heated floor with their own hands
Underfloor heating is a practical and cost-effective heating system that is widely used. Its main advantages are practically total absence of losses of radiated heat, uniform heating of the air over the entire area of the room and high efficiency at rather low power consumption. In addition, such systems are environmentally friendly and fully comply with all SNIP requirements, which allows them to operate in all types of premises.
You can do the installation of floor heating in your house yourself. The main thing is to correctly calculate the parameters of the system, select materials and equipment, and during the works, follow the technology of laying. How to do it, we will tell in the article.
4.1 Preparation of the substrate 4.2 Waterproofing 4.3 Laying of the thermal insulation layer 4.4 Installing the distribution manifold 4.5 Pipe laying 4.6 Casting a concrete screed
Installation of water underfloor heating
The task is quite complex, but doable. Only the subfloor has to be leveled first. This is a very important requirement, given that the leveling is still needed and the first layer of screed to do this more effectively. Why?
For example, the height difference in the room is 3 cm. If you immediately lay the pipe and only then level the screed, it turns out that in one corner of the height of the cement mixture will be minimum. 4 cm, and the other 7. So, during the operation of underfloor heating, it will heat 4 cm on one side and 7 cm on the other side of the concrete. Such an uneven load, very deleterious effect on the entire system as a whole and leads to rapid deterioration of the floor covering.
Therefore, the first and important step is to level the floors. For the preparation of concrete floors will need:
- Beacon profile;
- Laser level;
- Construction Angle;
- 5-10 kg of gypsum;
- Primer;
- Mobile concrete mixer;
- Cement;
- PGS;
- Polypropylene fiber.
Floors are swept and primed. While the ground dries, set the beacons. To do this, in the middle of the room set the laser level so that the projection of the horizontal beam was at a height of 15-20 cm from the floor. Then measure the height from the floor to the beam in different corners of the room with an angle piece and by the results determine the highest point. At this point, the height of the screed will be the minimum allowable. 4 cm. For the rest of the spots. according to the need.
To install the beacons, the plaster is diluted to a state of thick sour cream. Then make small piles of the resulting mass along one wall, with a spacing of 60-80 cm, on them lay the lighthouse profile. Putting an angle piece to it, align it with the level of the horizon, placing it at the desired height. From the wall to the first screed should be 50 cm. Between adjacent beacons distance varies depending on the length of the rule (aim for 1-1.3 m). Note, the plaster sets quickly, the work is carried out “without a break.
After about 30-40 m, you can pour the screed. Cement is diluted with CBC at a ratio of 1:5. Polypropylene fiber is added at a rate of 80 gr. per 100 liters of mixture. Fiber is an element of dispersed reinforcement, qualitatively increasing the strength of the coating. In addition, after curing, the new surface will be perfectly smooth.
Pour the resulting mixture so that each successive portion, 10-15 cm went to the previous. The screed is leveled by the rule, with an orientation on the beams.
After pouring the entire surface, you need time for the technical maturation of the cement-sand screed. The calculation is approximately as follows: 1 cm of thickness. 1 week.
Water heated floors with their own hands: the scheme of laying, installation technology on the website Nedvio
High cost of gas connection, and sometimes the impossibility of this type of heating, makes developers of private houses look for more and more new solutions how to heat your home. Today we will talk about the heating system of the house by installing water underfloor heating, consider their scheme of laying and technology of installation.
Let’s start with what this technology is. In the traditional form, the system of water heated floors is a concrete screed, in the thickness of which there are coils of pipes. Therefore, when you do water underfloor heating with his hands, the first thing you need to do is to insulate the concrete base of the floor, in order to avoid heat loss.
Features of the connection of the construction to the heat source
In the floor loop most often the average temperature of the coolant is 35-40 degrees. Mounting schemes water heating floors in a private home operates with the help of a forced flow. Part of the heat transfer medium from the return flow into the supply circuit.
Gas boilers are equipped with a special automatic. Solid fuel units require a more complex device. They are equipped with circulation pumps and a special buffer tank. It uses a more complex regulation of combustion.
Electric boilers are considered the best option for the underfloor heating system. Special automation allows you to maintain the desired temperature without losing heat output.
Useful information! For heating small area houses direct connection to the electric boiler is used. In cottages with a large area a special distribution comb is used.
Underfloor heating: types, features, as well as how to make a water heated floor in the apartment with their own hands, step by step actions
Underfloor heating is sometimes the only solution to ensure comfortable and cosy living in a private house, especially in northern regions. In the objects of individual residential construction often make warm water floors. Installation circuits in a private home can be very different, but the essence is the same. this heating system has been and remains the most frequently arranged is in the house. What are the features of water floors? How you can make them yourself?
Installing
Before proceeding to the direct installation, do not forget to prepare the surface. clean it from debris, small irregularities, dirt and dust. It is recommended to fill all irregularities with sand.
- Waterproofing. It is laid in different ways, it can be under the insulation, and over it. In the case of laying extruded polystyrene foam does not matter where the waterproofing will be located, because he himself does not really need it. The only thing. it will not allow excess moisture to penetrate into the board, where the hot water pipes will be located. It is recommended to install it on wooden beams.
How to Install a Heated Floor System
If you fix it below the insulation, it is possible to mount the pipes directly on it. In the case of fixing the top will need to lay more mounting grid, on which the pipes will be attached.
- Damper tape. Tape should be glued on the perimeter. The height is better to take a little higher than the pouring itself. In the future, what protrudes can be trimmed.
- Insulation. Lay it with an offset of joints to increase the strength of attachment.
- Reinforcement. It is recommended to install the first layer above the insulation to fix it over the contours and distribute heat. Mesh is tied together with wires for strength, and then pipes are attached to them. Do not forget to put reinforcement on top of pipes as well.
- Fastening of the pipes. Before fixing them, make an indentation from all walls of 15-20 centimeters. You can lay according to different schemes. a spiral or a snake.
- Connecting the circuits. It is recommended to do this through the distribution unit, which has a function of increasing pressure and temperature control.
- Determining the pressure. When you install everything you need, you need to check the system for durability. You need a compressor with which to carry out all the work.
- Floor plastering. is made after laying the circuits.
Disadvantages of underfloor heating
Unfortunately, in high-rise buildings built decades ago, it will be quite difficult to make a water heated floor. such apartments (or rather, the heating system in them) are simply not adapted for this technological solution. If such a floor will be installed, then in the winter the neighbors will complain about the cold in the apartment. And the homeowner is unlikely to be happy with the temperature readings at home. The management company also likely will not give permission to install underfloor heating. In this case, it is best to install electric underfloor heating. it does not need a permit.
For your information! In new buildings now, as a rule, a special heating system is installed, which allows you to connect the underfloor heating to it. In such buildings, you don’t even have to ask the housing and utilities department for permission to install.