How to calculate a warm water floor - an important step in system design

Underfloor heating systems are becoming more and more popular. They allow you to provide additional comfort and coziness in the house. It is often used both in private houses and in apartments. Naturally, it must be mounted correctly so that its effectiveness is not reduced due to design errors. To do this, you should calculate the warm water floor. To do this is not as easy as it seems at first glance, because you need to take into account a lot of factors. The article is of a review nature, because. only a specialist can accurately calculate a specific project.

Before you start designing a structure, you need to figure out what components it includes:

• Heating boiler.
• Collector and a special cabinet for it.
• Hydro and thermal insulation.
• Pipes.
• Fitting.
• Pumping and mixing unit.
• Reinforced screed.

What factors should be taken into account?

In order for the underfloor heating project to turn out to be working, it is necessary to calculate it taking into account some recommendations of specialists:

1. First you need to calculate the total area of ​​\u200b\u200bheating. It depends on how many circuits there will be in the system. At the same time, keep in mind that one circuit can heat no more than 40 m2. Its length should not exceed 100 m.
2. The distance between the pipes, regardless of which laying project you have chosen (snail, snake or other), should not exceed 30 cm.
3. Each circuit must be connected to a separate collector outlet.
4. It is also necessary to take into account the layout of all the premises of the house, the design of its external walls.
5. The size and type of windows installed in the rooms are important. The calculation of the power of the structure depends on this.

In addition, the following parameters must be taken into account:

• The temperature regime of the climatic zone in which you live, as well as the thermal regime inside each room.
• The need to adjust the temperature in each room separately.
• Type of flooring.
• Location of collectors and heat generator.
• Humidity in the room.
• Presence of mechanical ventilation of the house.
• Presence of other heat sources.
• The area of ​​structures that perform the function of a fence, and their heat transfer.
• pump performance.

Also, the design of underfloor heating depends on what kind of heat-insulating material you will use, as well as on the height of the screed and the material of its manufacture.

System installation rules

The calculation of the warm floor must also be made, observing some rules for the installation of the structure:

1. it is better to fix in the center of the room.
2. If there is a high level of humidity in the room, then it is better to reduce the step between the pipes to 15 cm.
3. If according to the project more than 1 collector is required in the system, then additional balancing valves will have to be installed.
4. The manifold must have a minimum pressure of at least 20 kPa.

What should be the ideal underfloor heating?

So, now you will have the opportunity to consider the most optimal floor heating project:

• The height difference of the base must not exceed 3 mm.
• The thickness of the heat insulator with a reflective layer is 3 cm. It is better to use expanded polystyrene, the density of which is 35 kg / m3 or more.
• The concrete screed has a height of 4-10 cm, while it is additionally strengthened. This will additionally make it possible to properly redistribute heat.

• To create the optimal power of the system, it is better to use metal-plastic or cross-linked polyethylene pipes. Moreover, their diameter is 16-20 mm.
• , which will be poured over the system, should contain fine gravel.

Please note that you can not save on insulation. Otherwise, system performance may be reduced.

Calculation of the required number of pipes

When creating a project for the construction of a floor heating system, it is necessary to correctly calculate the length of the pipeline. To do this, you need to know the area of ​​​​the heating zone on which the pipe system will be laid. The calculation should exclude areas for furniture, household appliances.

As an example, there is a 10 m2 room with 2x5 m walls. To calculate the size of the working area, you need to measure the length of all walls and subtract 30 cm from them (for example, the distance from the wall to the pipes).

S pom - f * (L1 + L2 + L3 + L4) \u003d Dwork

S pom - the total area of ​​​​the room;

f - indentation from the walls;

L1, L2, L3, L4 - the length of each wall;

Dwork - working area.

Taking into account these values, the working area will be equal to 5.8 m2. Further, the design of underfloor heating should take into account the heat loss in the room. They depend on the type and size of windows, the width and material of the walls, the height of the ceiling. The more losses there are, the smaller the step will have to be taken between the pipes. For example, if the lowest outdoor temperature in winter is -30 ° C, then it is advisable to use the following distance between the turns of pipes: 10-12 cm. If there are additional heat sources, then the step can be increased to 15-20 cm.

The required number of pipes is calculated using a different formula:

L = Scom/a+2*Lzu-2*Ld

L - length of pipes for underfloor heating (m);

Scom - area of ​​the heated room (m2);

a is the distance between the turns of the pipes (m);

Lzu - length of return or supply pipelines (m);

Ld is the length of the through pipes of the remaining heating circuits (m).

Features of calculating the temperature of the coolant

To determine this parameter, there is also a formula:

T is the required final temperature;

TR is the temperature that is fixed at the inlet to the circuit;

TO is the temperature at its outlet.

The most optimal parameters for the temperature of the coolant at the inlet to the circuit and the outlet are: 55/45, 50/40, 45/35 °C.

A detailed series of videos on the calculation of a water-heated floor system:

Now you know how to calculate the underfloor heating correctly. A specialist can do this more precisely. He will also help you choose a pipe laying scheme and advise on the selection of equipment. You can also carry out all the necessary calculations using online calculators, where you just need to enter the required parameters of the room. Leave comments on the article!