What is the maximum length of a pipe for a warm floor. How to calculate a water heated floor? Determining the length of the "warm floor" contour

We continue to disassemble underfloor heating design, started in the previous article, and now we will consider the main design recommendations.

What should be the surface temperature of the warm floor?

Actually, I already wrote about this in a separate article, but it will not be superfluous to repeat it. The following are maximum floor surface temperatures for rooms for different purposes:

for residential premises and workrooms in which people mostly stand: 21 ... 27 degrees;
for living rooms and offices: 29 degrees;
for lobbies, hallways and corridors: 30 degrees;
for baths, pools: 33 degrees
for rooms in which vigorous activity takes place: 17 degrees
in rooms with limited stay of people ( industrial premises) a maximum floor temperature of 37 degrees is allowed.

In the edge zones up to 35 degrees.

What is the temperature of the coolant in the water floor heating system?

The supply water temperature should be between 40 and 55 degrees. The maximum temperature of the coolant at the inlet to the water floor heating system should not exceed +60 degrees.

The coolant temperature difference between the supply and return pipelines is optimal 5 ... 15 degrees. Less than five degrees is not recommended due to the greatly increasing coolant flow through the circuit, which leads to large pressure losses. More than fifteen degrees is not recommended due to a noticeable temperature drop on the surface of the floor itself (in this case, under the windows we can have 27 degrees, at the end of the circuit 22 degrees, such a large difference is not comfortable). The optimum temperature drop is 10 degrees. Recommended temperatures at the entrance / exit of the loops: 55/45 degrees, 50/40 degrees, 45/35 degrees, 40/30 degrees.

If a heat pump unit is used as a heat source (although this is a rarity), then it is advisable to take the temperature of the supply coolant to the heating circuit at 40 degrees. In all other cases, any other supply temperature within the above range can be used.

What should be the length of the water heating pipes?

The maximum length of one circuit (loop) depends on the diameter of the pipes used:

with a diameter of 16 mm - 70 ... 90 meters;
with a diameter of 17 mm - 90 ... 100 m;
with a diameter of 20 mm - 120 m.

The difference in lengths is explained by the different hydraulic resistance and thermal load of the pipes different diameters. Well, it’s clear: the thicker the pipe, the less hydraulic resistance (resistance to the flow of liquid) in it.

Usually one circuit heats one room. But if the area of \u200b\u200bthe room is large, the length of the circuit is greater than the optimal one, then it is better to make two circuits per room than to lay a pipe that is too long.

If, when designing and calculating, we take one pipe diameter and then mount another, then the hydraulics of the system will be different. So it is better and correct to allow all experiments at the design and calculation stage, compare the results, choose the best one and follow it.

If two or more circuits are laid in the room, it is necessary to strive for their lengths to be the same (the length of the circuit is considered the entire pipe, starting from the collector, and not just that part of it that is directly in the heated room itself).

Of course, in practice, it is impossible to adjust the length perfectly, but you need to strive for this and the difference should be no more than 10 m!

The rooms in the house, as you know, have a different area. To lay as many meters of pipe in a smaller room as in a larger one, you need to take a smaller step between the turns.

If the room is small and the heat loss from it is not large (toilet, hallway), then you can combine the circuits, heat from the return pipe of the adjacent circuit.

With what step to lay out the pipes of the warm floor?

The step (distance between adjacent pipe turns) of pipe laying is from 15 to 30 cm (15, 20, 25, 30 cm - that is, not 21; 22.4; 27, etc., but in increments of 5 cm in the specified range 15-30 cm). A pipe laying step of 30, 35, 40, 45 cm is allowed in large rooms (gyms, etc.). And 10 cm near large windows, external walls (in the so-called edge zones).

The pipe layout step is selected depending on the heat load, type of room, circuit length, coating material, etc.:

edge zones - 100 ... 150 mm (standard number of rows in the edge zone - 6);
central zones 200…300 mm;
bathrooms, bathrooms, shower rooms, etc. are completely laid in steps of 100 ... 150 mm. The same step may not work because of the need to bypass the plumbing and because of the tightness in the room;
in rooms where the floor will be covered with a material with good thermal conductivity ( tile, marble, porcelain stoneware) pipe laying step - 200 mm.

Attention! Above are the recommended numbers. In practice, it is often impossible to bend a metal-plastic pipe with a small radius without the danger of breaking it (when laying with a snake). Therefore, when laying with a snake, a step of 150 ... 200 mm is better and optimal. And in general, take note for yourself: despite any recommendations and smart justifications, make a pipe step in the edge zones of 100 mm, and in the remaining 150 mm, and you will never lose.

A step of 300 mm will not give uniform heating of the floor at all (again, when laying with a snake).

How to choose the diameter of pipes for underfloor heating systems?

IN residential buildings or apartments with an area ranging from 50 m2 to infinity - a pipe with a diameter of 16 mm is used. You don't need more!

Even in well-insulated houses, it is desirable that the pipe pitch does not exceed 150, maximum 200 mm - and the 16th pipe makes it possible to meet all these conditions. In general, pipes of larger diameter are not needed for a private house: they are optimal in terms of the ratio "ease of installation - price - volume of coolant".

Another pipe commonly used is 18mm. However, one must understand that a thicker pipe is an extra cost, and not only for the pipe, but also for fittings and everything else.

Sometimes they put a pipe with a diameter of 20 mm, not taking into account the characteristics. And in such a pipe, the amount of water is already significantly larger, which is why more energy is required for heating. Yes, and it is difficult to mount such a pipe: bending it for laying with a snake and a step of 150 mm is unrealistic, and a larger step will not give heat in the house, and the cost of the coolant will be indecently decent. Such a pipe can be laid in some public buildings with high ceilings, while at the same time being there a large number of people. There will be a thick screed! For a pipe of 16 mm, the thickness of the screed is sufficient 50 mm from the top of the pipe. Allowed up to 80 mm.

What should be the diameter of the pipes from the boiler to the collector?

The task is to connect one, two or more underfloor heating collectors.

Almost every underfloor heating collector has a 1 inch (25 mm) thread for connecting to the main - it doesn’t matter if it is internal or external.

There are manifolds with an inch and a quarter thread, but this is for large industrial or public institutions where a larger diameter pipe will be used, so you do NOT need to take such manifolds for a private house.

It does not make sense to initially narrow or “broaden” the diameters of the main pipes (i.e., supplying the coolant from the boiler), but it makes sense to take the same diameter as the collector inlet, i.e. 1 inch. For a polypropylene pipe, this is a diameter of 32 mm (this is the outer one, and the inner one is just 25 mm). For metal plastic pipe it is 26mm in diameter. For copper - 28 mm. These are the standard options for using pipes. But if there are doubts about the number of circuits, then you can increase the diameter of the main pipes by one size (40, 32 and 32 mm for polypropylene, metal-plastic and copper pipes, respectively; an adapter is required to go 1 inch).

Pipes made of cross-linked polyethylene (PEX) have the same dimensions as metal-plastic pipes in terms of wall thickness and diameters.

Other data for the design of underfloor heating

It is not advisable to connect the concrete and deck system to the same mixing unit (and header).

One circuit should be for one room (in the sense, you don’t need to be weird by unfolding the loop, filling in the screed, and then dividing the room with a partition).

It is desirable to place the collector in the middle of the house. If it doesn’t work out, then the problem with the difference in the lengths of the loops is solved by installing flow meters on the manifold: with their help, the uniform flow of the coolant through the loops of different lengths is regulated.

If the circuits have a length of 90 m (or even more), then a maximum of nine circuits can be "clung" to one collector. With loop lengths of 60 ... 80 m, up to 11 circuits can be mounted on one collector.

It is not necessary to “pressure” two (or more) collectors with one pump. It is correct to install separate pumps for each manifold group.

Mixing modules (mixing units) are not all suitable for any length of pipes of underfloor heating loops, so check when buying.

For an accurate calculation, it is necessary to take into account not only heat losses, but also the possible heat influx into the premises - for example, from operating equipment, household appliances, etc. (it hardly makes sense to fool around when calculating the heating of a private house), heat inflow through the ceiling - if There is also underfloor heating in the upper room. The calculation of multi-storey buildings must be carried out, starting from the premises of the upper floor to the lower ones. Because heat losses through the floor of the second floor are a useful heat gain for the premises of the first floor.

The thickness of the insulation on the first and basement floors is at least 50 mm (in reality, it depends on the climatic zone: what is good for the south does not roll at all in the north), on other floors - at least 30 mm. A logical question: why insulate the ceiling between the first and second floors, let the heat from the warm floor on the second floor also warm the first floor? Answer: if the ceiling is concrete, then the insulation is placed so as not to heat the ceiling itself, because it is very costly both in terms of money and time.

The maximum head loss in the circuit is 15 kPa (optimally 13 kPa). If the circuit has a head loss of more than 15 kPa, it is necessary to reduce the coolant flow or divide the floor area in the room into several circuits. What this means, we will consider in one of the following articles, when we perform calculations on a specific example.

Minimum flow coolant in one circuit is at least 27-30 liters per hour. Otherwise, the contours must be combined. Why such a limitation? At a lower flow rate, the coolant, not having time to go through the entire circuit, but it will have time to cool down - the floor will be cold! The minimum flow rate of the coolant on each circuit can be set on the control valve (flow meter) installed on the manifold.

The above requirements for underfloor heating design will need to be taken into account when performing underfloor heating calculations, when we do this in a special program. So, if these terms mean nothing to you yet, don't worry, in due time everything will fall into place. However, I recommend that you make a note for yourself somewhere in order to return to the information in this article when calculating.

underfloor heating design

Today it is difficult to imagine Vacation home no floor heating. Before starting the installation of heating, it is necessary to calculate the length of the pipe, which is used for underfloor heating. Almost every country house has its own heat supply system, the owners of such houses independently install a water floor - if this is provided for by the layout of the premises. Of course, it is possible to install such a warm floor in apartments, but such a process can bring a lot of trouble to both apartment owners and employees. This is due to the fact that it is impossible to bring a warm floor to the heating system, and installing an additional boiler is problematic.

The dimensions and shape of the pipe for underfloor heating can be different, therefore, in order to understand how to calculate a warm floor, you need to understand the system and structure of such a system in more detail.

How can you install underfloor heating?

There are several ways to install underfloor heating. As an example, consider 2 ways.

Grazing. This floor has a flooring made of various materials, such as polystyrene or wood. It is worth noting that such a floor is faster to install and put into operation, since it does not require additional time to fill the screed and dry it.

Concrete. Such a floor has a screed, which will take more time to apply, so if you want to make a warm floor as quickly as possible, then this option will not suit you.

In any case, installing a warm floor is a difficult task, so it is not recommended to carry out this process on your own. If there are no additional funds for employees, then the installation of the floor can be carried out independently, but strictly following the installation instructions.

Underfloor heating concrete installation

Despite the fact that laying a warm floor in this way takes longer, it is more popular. A pipe for a warm floor is selected depending on the materials. It is worth noting that the price of the pipe will also depend on the material from which it is made. The pipe with this method is laid along the contour. After laying the pipe, it is poured with a concrete screed without additional heat-insulating materials.

Calculation and installation of a warm floor

Before proceeding with the installation of the floor, it is necessary to calculate the required number of pipes and other materials. The first step is to divide the room into several identical squares. The number of parts in a room depends on the area of the room and its geometry.

Calculator - the simplest calculation of pipe length:

Calculation of the required amount of pipe

The maximum length of the circuit required for a warm water floor should not exceed 120 meters. It is worth noting that such dimensions are indicated for several reasons.

Due to the fact that water in the pipes can affect the integrity of the screed, if it is installed incorrectly, the floor can be damaged. An increase or decrease in temperature negatively affects the quality of a wooden floor or linoleum. By choosing the optimal size of the squares, you distribute energy and water through the pipes more efficiently.

After the room is divided into parts, you can start planning the shape of the pipe laying.

Methods for laying pipes for underfloor heating

There are 4 ways to lay the pipe:

snake;
Double snake (fits into 2 pipes);
Snail. The pipe is laid in 2 times (bend) leaving one source gradually rounding towards the middle;
Corner snake. Two pipes come out from the same corner: the first pipe starts the snake, the second one ends.

Depending on which pipe laying method you choose, you need to calculate the number of pipes. It is worth noting that pipes can be laid in several ways.

Which styling method should you choose?

In large rooms that have a flat square or rectangular shape it is recommended to use the “snail” laying method, so that a large room will always be warm and cozy.

If the room is long or small, it is recommended to use a "snake".

Laying step

In order for a person’s feet not to feel the difference between the sections of the floor, it is necessary to adhere to a certain length between the pipes, at the edge this length should be about 10 cm, then with a difference of 5 cm, for example, 15 cm, 20 cm, 25 cm .

The distance between the pipes should not exceed 30 cm, otherwise it will be simply unpleasant to walk on such a floor.

Calculation of pipes for underfloor heating

On average, 1 m2 requires 5 running meters pipes. This method is easier to determine how many pipes per m2 are needed to equip a warm floor. With this calculation, the step length is 20 cm.
You can determine the required amount of pipe using the formula: L \u003d S / N * 1.1, where:

S is the area of the room.
N - Laying step.
1.1 - pipe margin for turns.

When calculating, it is also necessary to add the number of meters from the floor to the collector and back.
Example:

- Floor area (useful area): 15 m2;
- Distance from floor to collector: 4 m;
- The step of laying the warm floor: 15 cm (0.15 m.);
- Calculations: 15 / 0.15 * 1.1 + (4 * 2) = 118 m.

What should be the length of the water floor heating circuit?

These parameters must be calculated based on the diameter and material from which the pipes are made. So, for example, for metal-plastic pipes with a diameter of 16 inches, the length of the contour of a water-heated floor should not exceed 100 meters. The optimal length for such a pipe is 75-80 meters.

For pipes made of cross-linked polyethylene with a diameter of 18 mm, the length of the contour on the surface for a warm floor should not exceed 120 meters. In practice, this length is 90-100 meters.

For a metal-plastic pipe with a diameter of 20 mm, the maximum length of the warm floor should be approximately 100-120 meters, depending on the manufacturer.

It is recommended to choose pipes for laying on the floor based on the area of \u200b\u200bthe room. It is worth noting that their durability and quality of work depend on what material the pipes are made of and how they are laid on the surface. The best option would be metal-plastic pipes.

Floor installation steps

After you have chosen high-quality and reliable pipes, it is recommended to proceed with the installation of a warm floor. This must be done in several stages.

Installation of thermal insulation

At this stage, there are preparatory work, the floor is cleared and a layer of thermal insulation is laid. Styrofoam can act as thermal insulation. Styrofoam layers are laid on the subfloor. The thickness of the foam should not exceed 15 cm. It is recommended to calculate the thickness depending on the size of the room, its location in the apartment, as well as the individual preferences of the person.

Installation of waterproofing

After the foam is laid, it is necessary to lay a layer of waterproofing. Polyethylene film is suitable as a waterproofing. The plastic film is fixed to the walls (near the plinth), and the floor is reinforced with mesh from above.

Laying and fixing pipes

Next, you can lay pipes for underfloor heating. After you have calculated and selected a pipe laying scheme, this process will not take you much time. When laying pipes, they must be fixed on the reinforcing mesh with special stretch marks or clamps.

Crimping

Crimping is almost the last stage in the installation of a warm floor. Pressure testing must be carried out within 24 hours at operating pressure. Thanks to this stage, it is possible to identify and eliminate mechanical damage to pipes.

Pouring with concrete mortar

All flooring work is carried out under pressure. It is worth noting that the thickness of the concrete layer should not exceed 7 cm.

After the concrete has dried, you can lay the floor. As a floor covering, it is recommended to use tiles or linoleum. If you choose parquet or any other natural surface, due to possible temperature changes, such a surface may become unusable.

Collector cabinet and its installation

Before you calculate the pipe flow required for installation on the surface and underfloor heating, you need to prepare a place for the collector.

The collector is a device that maintains pressure in the pipes and heats the used water. Also, this device allows you to maintain the required temperature in the room. It is worth noting that it is necessary to buy a collector depending on the size of the room.

How and where should the manifold cabinet be installed?

There are no restrictions for installing a manifold cabinet, at the same time, there are several recommendations.

It is also not recommended to install the collector cabinet too high, since in the end the circulation of water may occur unevenly. The optimal height for installing the cabinet is 20-30 cm above the bare floor.

Tips for those who decide to install a warm floor on their own

There must be an air outlet in the collector cabinet from above. Laying a warm floor under furniture is strictly prohibited. Firstly, because it will lead to damage to the materials from which the furniture is made. Secondly, it can lead to fire. Materials that are highly flammable can easily catch fire if there is heat. Thirdly, the heat from the floor must constantly rise up, the furniture prevents this, so the pipes heat up faster and can deteriorate.

It is necessary to choose a collector depending on the size of the room. In the store, when buying, you need to pay attention to what dimensions this or that collector is designed for.

Pay attention to the advantages of certain materials from which the pipes are made.

The main qualities of pipes:

wear resistance;
Thermal resistance.

Buy pipes with an average diameter. If the pipe diameter is too large, the water will circulate for a very long time, and reaching the middle or end (depending on the laying method), the water will cool down, the same situation will occur with a pipe with a small diameter. Therefore, pipes with a diameter of 20-40 mm will be the best option.

Before you calculate a warm floor, consult with those who have already done it. Calculation of the area and number of pipes is an important step in preparing for floor installation. In order not to be mistaken, buy + 4 meters of pipe, this will allow you not to save on the pipe if it is not enough.

Before laying pipes, step back from the walls 20 cm in advance, this is the average distance over which the heat from the pipes acts. Calculate your steps wisely. If the distance between the pipes is calculated incorrectly, the room and floor will be heated in strips.

After installing the system, test it, so you can understand in advance whether the collector was installed correctly, as well as notice mechanical damage.

If you install the underfloor heating correctly, it will serve you for many years. If you have any questions, it is better to ask them to an expert of our site or contact specialists who will qualitatively, quickly and reliably improve and prepare your room for installing a warm floor.

Warm floor perfect solution to improve your home. The floor temperature directly depends on the length of the underfloor heating pipes hidden in the screed. The pipe in the floor is laid in loops. In fact, the total length of the pipe is added up from the number of loops and their length. It is clear that the longer the pipe in the same volume, the warmer the floor. In this article, we will talk about restrictions on the length of one contour of a warm floor.

Approximate design characteristics for pipes with a diameter of 16 and 20 mm are: 80-100 and 100-120 meters, respectively. These data are approximate for approximate calculations. Let's take a closer look at the process of installing and pouring underfloor heating.

Consequences of exceeding the length

Let's figure out what consequences an increase in the length of the underfloor heating pipe can lead to. One of the reasons is an increase in hydraulic resistance, which will create an additional load on the hydraulic pump, as a result of which it may fail or simply may not cope with the task assigned to it. The resistance calculation consists of many parameters. Conditions, styling parameters. The material of the pipes used. Here are the three main ones: loop length, number of bends and thermal load on it.

It is worth noting that the thermal load increases with the increase in the loop. The flow rate and hydraulic resistance also increase. There are restrictions on the flow rate. It should not exceed 0.5 m/s. If we exceed this value, various noise effects may occur in the piping system. The main parameter, for the sake of which this calculation is made, also increases. The hydraulic resistance of our system. It also has limitations. They are 30-40 kP per loop.

The next reason is that with an increase in the length of the underfloor heating pipe, the pressure on the pipe walls increases, causing this section to elongate when heated. The pipe in the screed has nowhere to go. And it will begin to narrow at its weakest point. The constriction can cause blockage of the flow in the coolant. For pipes made from different material, different coefficient extensions. For example, polymer pipes have a very high expansion coefficient. All these parameters must be taken into account when installing a warm floor.

Therefore, it is necessary to fill in the underfloor heating screed with pressed pipes. Pressurize better with air with a pressure of approximately 4 bar. Thus, when you fill the system with water and start heating it, the pipe in the screed will expand somewhere.

Optimum pipe length

Considering all the above reasons, taking into account the corrections for the linear expansion of the pipe material, we take as a basis the maximum length of the underfloor heating pipes per circuit:

What is the optimal length of the underfloor heating pipe?
Let's find out the optimal length of the underfloor heating pipe and what could be the consequences if the circuit is longer. Everything in our article

One of the conditions for the implementation of high-quality and proper heating of a room with a warm floor is to maintain the temperature of the coolant in accordance with the specified parameters.

These parameters are determined by the project, taking into account the required amount of heat for the heated room and flooring.

Required data for calculation

To maintain the set temperature in the room, it is necessary to correctly calculate the length of the loops used to circulate the coolant.

First, you need to collect the initial data on the basis of which the calculation will be performed and which consist of the following indicators and characteristics:

the temperature that should be above the floor covering,
layout diagram of loops with coolant,
distance between pipes
maximum possible pipe length,
the possibility of using several contours of different lengths,
connection of several loops to one collector and to one pump and their possible number with such a connection.

Based on the above data, it is possible to correctly calculate the length of the underfloor heating circuit and thus ensure a comfortable temperature regime indoors with minimal energy bills.

Floor temperature

The temperature on the surface of the floor, made with a water heating device underneath, depends on the functional purpose of the room. Its values should not exceed those specified in the table:

Pipe laying options used for underfloor heating

The laying scheme can be performed with a regular, double and corner snake or snail. Various combinations of these options are also possible, for example, along the edge of the room you can lay out a pipe with a snake, and then the middle part with a snail.

IN large rooms complex configuration, it is better to lay with a snail. In rooms of small size and with a variety of complex configurations, snake laying is used.

Distance between pipes

The pipe laying step is determined by calculation and usually corresponds to 15, 20 and 25 cm, but no more. When laying out the pipes with a step of more than 25 cm, the human foot will feel the temperature difference between and directly above them.

At the edges of the room, the heating circuit pipe is laid in increments of 10 cm.

Permissible contour length

It depends on the pressure in a particular closed loop and hydraulic resistance, the values of which determine the diameter of the pipes and the volume of fluid that is fed into them per unit time.

When installing a warm floor, situations often occur when the circulation of the coolant in a separate loop is disturbed, which cannot be restored by any pump, water is locked in this circuit, as a result of which it cools down. This results in pressure losses of up to 0.2 bar.

Based on practical experience, you can adhere to the following recommended sizes:

Less than 100 m can be a loop made of a metal-plastic pipe with a diameter of 16 mm. For reliability, the optimal size is 80 m.
Not more than 120 m take the maximum length of the circuit of 18 mm pipes made of cross-linked polyethylene. Experts are trying to install a circuit with a length of 80-100 m.
No more than 120-125 m, the size of the loop for metal-plastic with a diameter of 20 mm is considered acceptable. In practice, they also try to reduce this length to ensure sufficient reliability of the system.

For a more accurate determination of the size of the loop length for the underfloor heating in the room under consideration, in which there will be no problems with the circulation of the coolant, it is necessary to perform calculations.

Application of several contours of different lengths

For example, it is necessary to implement a floor heating system in several rooms, one of which, for example, a bathroom, has an area of 4 m2. This means that 40 m of pipe will be needed to heat it. It is not advisable to arrange contours of 40 m in other rooms, while loops of 80-100 m can be made.

The difference in pipe lengths is determined by calculation. If it is impossible to perform calculations, a requirement can be applied that allows a difference in the length of the contours of the order of 30-40%.

Also, the difference in the lengths of the loops can be compensated by increasing or decreasing the diameter of the pipe and changing the pitch of its laying.

Ability to connect to one node and pump

The number of loops that can be connected to one collector and one pump is determined depending on the power of the equipment used, the number of thermal circuits, the diameter and material of the pipes used, the area of heated premises, the material of the enclosing structures, and many other various indicators.

Such calculations must be entrusted to specialists with knowledge and practical skills in the implementation of such projects.

Loop size determination

Having collected all the initial data, considering possible options creating a heated floor and having determined the most optimal of them, you can proceed directly to calculating the length of the contour of a water heated floor.

To do this, it is necessary to divide the area of \u200b\u200bthe room in which the loops for water floor heating are laid by the distance between the pipes and multiply by a factor of 1.1, which takes into account 10% for turns and bends.

You can determine the length of the loop laid in 20 cm increments in a room of 10 m2, located at a distance of 3 m from the collector, by doing the following:

In this room, 61 m of pipe must be laid, forming a heating circuit, in order to ensure the possibility of high-quality heating of the floor covering.

The presented calculation helps to create conditions for maintaining comfortable temperature air in small separate rooms.

In order to correctly determine the length of the pipe of several thermal circuits for a large number of rooms powered by one collector, it is necessary to involve a design organization.

She will do this with the help of specialized programs that take into account many different factors on which the uninterrupted circulation of water depends, and hence the high-quality floor heating.

The optimal length of the contour of the warm floor
One of the conditions for the implementation of high-quality and proper heating of the room with the help of a warm floor is the optimal length of the contour of the warm floor.

Seven times to measure calls for folk wisdom. And you can't argue with that.

In practice, to embody what has repeatedly scrolled in the head is not easy.

In this article we will talk about the work related to the communications of a warm water floor, in particular, we will pay attention to the length of its contour.

If we are planning to install a water heated floor, the length of the circuit is one of the first issues that needs to be dealt with.

Pipe arrangement

The underfloor heating system includes a considerable list of elements. We are interested in tubes. It is their length that determines the concept of "the maximum length of a warm water floor." It is necessary to lay them taking into account the characteristics of the room.

Based on this, we get four options, known as:

If done correct styling, then each of the listed types will be effective for space heating. Different can be (and most likely will be) the footage of the pipe and the volume of water. The maximum length of the water-heated floor circuit for a particular room will depend on this.

Main calculations: water volume and pipeline length

There are no tricks here, on the contrary - everything is very simple. For example, we chose the snake option. We will use a number of indicators, among which is the length of the contour of a water-heated floor. Another parameter is the diameter. Mostly pipes with a diameter of 2 cm are used.

We also take into account the distance from the pipes to the wall. Here it is recommended to fit in the range of 20-30 cm, but it is better to place the pipes clearly at a distance of 20 cm.

The distance between the pipes themselves is 30 cm. The width of the pipe itself is 3 cm. In practice, we get a distance between them of 27 cm.
Now let's move on to the area of the room.

This indicator will be decisive for such a parameter of a warm water floor as the length of the circuit:

Let's say our room is 5 meters long and 4 meters wide.
The laying of the pipeline of our system always starts from the smaller side, that is, from the width.
To create the basis of the pipeline, we take 15 pipes.
A gap of 10 cm remains near the walls, which then increases on each side by 5 cm.
The section between the pipeline and the collector is 40 cm. This distance exceeds the 20 cm from the wall that we talked about above, since a water drainage channel will have to be installed in this section.

Our indicators now make it possible to calculate the length of the pipeline: 15x3.4 \u003d 51 m. The entire circuit will take 56 m, since we should also take into account the length of the so-called. collector section, which is 5 m.

Quantity

One of the following questions: what is the maximum length of a water floor heating circuit? What to do if the room requires, for example, 130, or 140-150 m of pipe? The way out is very simple: it will be necessary to make more than one contour.

In the operation of a water-heated floor system, the main thing is efficiency. If, according to calculations, we need 160 m of pipe, then we make two circuits of 80 m each. After all, the optimal length of the contour of a water-heated floor should not exceed this indicator. This is due to the ability of the equipment to create the necessary pressure and circulation in the system.

It is not necessary to make the two pipelines absolutely equal, but it is also not desirable that the difference be noticeable. Experts believe that the difference may well reach 15 m.

We have also prepared the following useful information for you:

Maximum length of the water floor heating circuit

To determine this parameter, we must consider:

hydraulic resistance,
pressure loss in a particular circuit.

The listed parameters are determined, first of all, by the diameter of the pipes used for the warm water floor, the volume of the coolant (per unit of time).

In the installation of a warm floor, there is a concept - the effect of the so-called. locked loop. This is a situation where circulation through the loop will not be possible, regardless of the pump power. This effect inherent in a pressure loss situation of 0.2 bar (20 kPa).

In order not to confuse you with long calculations, we will write a few recommendations that have been proven by practice:

The maximum contour of 100 m is used for pipes with a diameter of 16 mm made of metal-plastic or polyethylene. Ideal option - 80 m
A contour of 120 m is the limit for a 18 mm pipe made of cross-linked polyethylene. However, it is better to limit yourself to a range of 80-100 m
With 20 mm plastic pipe, you can make a circuit of 120-125 m

Thus, the maximum length of a pipe for a warm water floor depends on a number of parameters, the main of which is the diameter and material of the pipe.

Read on our website about which is better to choose flooring for a warm water floor:

And also learn more here about how to make a warm water floor with your own hands.

Are two identical needed/possible?

Naturally, the situation will look ideal when the loops have the same length. In this case, you will not need any settings, the search for balance. But this is mostly in theory. If you look at practice, it turns out that it is not even advisable to achieve such a balance in a warm water floor.

The fact is that it is often necessary to lay a warm floor at an object consisting of several rooms. One of them is emphasized small, for example - a bathroom. Its area is 4-5 m2. In this case, a reasonable question arises - is it worth adjusting the entire area for a bathroom, splitting it into tiny sections?

Since this is not advisable, we come to a different question: how not to lose on pressure. And for this, elements such as balancing fittings have been created, the use of which consists in equalizing pressure losses along the contours.

Again, calculations can be used. But they are complex. From the practice of carrying out work on the installation of a warm water floor, we can safely say that the spread in the size of the contours is possible within 30-40%. In this case, we have every chance to get the maximum effect from the operation of a warm water floor.

Quantity with one pump

Another frequently asked question: how many circuits can operate on one mixing unit and one pump?
The question really needs to be clarified. For example, to the level - how many loops can be connected to the collector? In this case, we take into account the diameter of the collector, the volume of the coolant passing through the node per unit of time (the calculation is in m3 per hour).

We need to look at the data sheet of the node, where the maximum throughput factor is indicated. If we carry out calculations, then we will get the maximum indicator, but we cannot count on it.

One way or another, the maximum number of circuit connections is indicated on the device - as a rule, 12. Although, according to calculations, we can get both 15 and 17.

The maximum number of outlets in the collector does not exceed 12. Although there are exceptions.

We saw that installing a warm water floor is a very troublesome business. Especially in that part of it, where we are talking about the length of the contour. Therefore, it is better to contact specialists so as not to redo later a not entirely successful styling that will not bring the efficiency that you expected.

Laying and calculation of the maximum length of the water floor heating circuit
The article has detailed information about the maximum length of the water floor heating circuit, the location of the pipes, optimal calculations, as well as the number of circuits with one pump and whether two are the same.

The laying of heating pipes under the floor covering is considered one of the the best options heating a house or apartment. They consume fewer resources to maintain the specified temperature in the room, exceed standard wall-mounted radiators in terms of reliability, evenly distribute heat in the room, and do not create separate “cold” and “hot” zones.

The length of the water floor heating circuit is the most important parameter that must be determined before starting installation work. The future power of the system, the level of heating, the choice of components and structural units depend on it.

Styling options

Four common pipe laying patterns are used by builders, each better suited for use in a different room shape. From their "drawing" to a large extent depends on the maximum length of the contour of the warm floor. This:

"Snake". Sequential laying, where the hot and cold lines follow each other. Suitable for elongated rooms with division into zones of different temperatures.
"Double snake". It is used in rectangular rooms, but without zoning. Provides uniform heating of the area.
"Corner snake". Sequential system for a room with equal wall lengths and a low heating zone.
"Snail". Dual routing system suitable for square-shaped rooms with no cold spots.

The chosen laying option affects the maximum length of the water floor, because the number of pipe loops and the bending radius change, which also “eats” a certain percentage of the material.

Length calculation

The maximum length of the underfloor heating pipe for each circuit is calculated separately. To get the required value, you need the following formula:

Values are in meters and mean the following:

W is the width of the room.
D is the length of the room.
Shu - “laying step” (distance between loops).
K is the distance from the collector to the connection point with the circuits.

The length of the contour of the warm floor obtained as a result of calculations is additionally increased by 5%, which includes a small margin for leveling errors, changing the bending radius of the pipe and connecting with fittings.

As an example of calculating the maximum pipe length for a warm floor for 1 circuit, let's take a room of 18 m2 with sides of 6 and 3 m. The distance to the collector is 4 m, and the laying step is 20 cm, the following is obtained:

5% is added to the result, which is 4.94 m and the recommended length of the water floor heating circuit is increased to 103.74 m, which are rounded up to 104 m.

Dependence on pipe diameter

The second most important characteristic is the diameter of the pipe used. It directly affects the maximum length value, the number of circuits in the room and the power of the pump, which is responsible for the circulation of the coolant.

In apartments and houses with an average size of rooms, pipes of 16, 18 or 20 mm are used. The first value is optimal for residential premises, it is balanced in terms of costs and performance. The maximum length of the water floor heating circuit with 16 pipes is 90-100 m, depending on the choice of pipe material. It is not recommended to exceed this indicator, because the so-called “locked loop” effect may form, when, regardless of the pump power, the movement of the coolant in the communication stops due to high fluid resistance.

To choose optimal solution and take into account all the nuances, it is better to contact our specialist for advice.

Number of circuits and power

The installation of the heating system must comply with the following recommendations:

One loop per room of a small area or part of a large one; it is irrational to stretch the contour over several rooms.
One pump per manifold, even if the declared capacity is enough to provide two "combs".
With a maximum length of the underfloor heating pipe of 16 mm in 100 m, the collector is installed on no more than 9 loops.

If the maximum length of the underfloor heating loop 16 of the pipe exceeds the recommended value, then the room is divided into separate circuits, which are connected into one heating network collector. To ensure an even distribution of the coolant throughout the system, experts advise not to exceed the difference between individual loops of 15 m, otherwise the smaller circuit will warm up much more than the larger one.

But what if the length of the underfloor heating contour of 16 mm pipes differs by a value that exceeds 15 m? Balancing fittings will help, which changes the amount of coolant circulating through each loop. With its help, the difference in length can be almost two times.

Temperature in the rooms

Also, the length of the underfloor heating circuits for 16 pipes affects the level of heating. To maintain a comfortable indoor environment, a certain temperature is needed. To do this, the water pumped in the system is heated to 55-60 °C. Exceeding this indicator can adversely affect the integrity of the engineering communications material. Depending on the purpose of the room, on average, we get:

27-29 °C for living rooms,
34-35 °C in corridors, hallways and walk-through rooms,
32-33 °C in rooms with high humidity.

In accordance with the maximum length of the underfloor heating circuit 16 mm in 90-100 m, the difference at the "inlet" and "outlet" of the mixing boiler should not exceed 5 ° C, a different value indicates heat loss on the heating main.

The maximum length of the contour of a water-heated floor: laying and calculating the optimal value
Laying heating pipes under the floor is considered one of the best options for heating a house or apartment. They consume fewer resources to maintain the specified temperature in the room, exceed standard wall-mounted radiators in terms of reliability, evenly distribute heat in the room, and do not create separate

Topics covered here include: the maximum length of a water-heated floor circuit, the location of pipes, optimal calculations, as well as the number of circuits with one pump and whether two are the same.

Seven times to measure calls for folk wisdom. And you can't argue with that.

In practice, to embody what has repeatedly scrolled in the head is not easy.

In this article we will talk about the work related to the communications of a warm water floor, in particular, we will pay attention to the length of its contour.

If we are planning to install a water heated floor, the length of the circuit is one of the first issues that needs to be dealt with.

Pipe arrangement

Based on this, we get four options, known as:

snake;
double snake;
corner snake;
snail.

If you make the right styling, then each of the listed types will be effective for space heating. Different can be (and most likely will be) the footage of the pipe and the volume of water. The maximum length of the water-heated floor circuit for a particular room will depend on this.

Main calculations: water volume and pipeline length

We also take into account the distance from the pipes to the wall. Here it is recommended to fit in the range of 20-30 cm, but it is better to place the pipes clearly at a distance of 20 cm.

Let's say our room is 5 meters long and 4 meters wide.
The laying of the pipeline of our system always starts from the smaller side, that is, from the width.
To create the basis of the pipeline, we take 15 pipes.
A gap of 10 cm remains near the walls, which then increases on each side by 5 cm.
The section between the pipeline and the collector is 40 cm. This distance exceeds the 20 cm from the wall that we talked about above, since a water drainage channel will have to be installed in this section.

The length of the pipes of the entire system must fit into the allowable range - 40-100 m.

Quantity

It is not necessary to make the two pipelines absolutely equal, but it is also not desirable that the difference be noticeable. Experts believe that the difference may well reach 15 m.

Maximum length of the water floor heating circuit

To determine this parameter, we must consider:

The listed parameters are determined, first of all, by the diameter of the pipes used for the warm water floor, the volume of the coolant (per unit of time).

In the installation of a warm floor, there is a concept - the effect of the so-called. locked loop. This is a situation where circulation through the loop will not be possible, regardless of the pump power. This effect is inherent in the situation of a pressure loss of 0.2 bar (20 kPa).

In order not to confuse you with long calculations, we will write a few recommendations that have been proven by practice:

The maximum contour of 100 m is used for pipes with a diameter of 16 mm made of metal-plastic or polyethylene. Ideal option - 80 m
A contour of 120 m is the limit for a 18 mm pipe made of cross-linked polyethylene. However, it is better to limit yourself to a range of 80-100 m
With 20 mm plastic pipe, you can make a circuit of 120-125 m

Thus, the maximum length of a pipe for a warm water floor depends on a number of parameters, the main of which is the diameter and material of the pipe.

Are two identical ones necessary and possible?

Despite the considerable amount of materials on how to make a water floor on your own, it is better to turn to specialists. Only masters can evaluate the working area and, if necessary, "manipulate" the pipe diameter, "cut" the area and combine the laying step when it comes to large areas.

Quantity with one pump

We need to look at the data sheet of the node, where the maximum throughput factor is indicated. If we carry out calculations, then we will get the maximum indicator, but we cannot count on it.

One way or another, the maximum number of circuit connections is indicated on the device - as a rule, 12. Although, according to calculations, we can get both 15 and 17.

The maximum number of outlets in the collector does not exceed 12. Although there are exceptions.

Today, the "warm floor" system is very popular among the owners of apartments and private houses. The vast majority of those who have heating system, or has already done the installation of a similar design in their housing, or is thinking about it. They are especially relevant in homes where there are small children who crawl and can freeze without adequate heating. These designs are much more economical than other heating systems. In addition, they interact better with the human body, since, unlike the electric version, they do not create magnetic fluxes. Among them positive qualities fire safety and high efficiency. In this case, the heated air is evenly distributed throughout the space of the room.

The principle is that lines are laid under the coating, through which the coolant circulates - as a rule, water, heating the floor surface and the room. This method copes with heating very effectively, provided that the design is correctly calculated and if its installation is done correctly.

System mounting options

There are two principles by which the installation of a warm water floor can be carried out - flooring and concrete. In both options, a heater is necessarily used under the contour of the water floor - this is necessary so that all the heat goes up and heats the home. If the heater is not used, the space below will also be heated, which is completely unacceptable, since it reduces the heating effect. As a heater, it is customary to use penoplex or penofol. Penoplex has excellent heat-insulating properties, repels moisture and does not lose its properties in a humid environment. It has good resistance to compressive loads, is easy to use and inexpensive. Penofol also has a foil layer, which serves as a reflector of thermal radiation inside the apartment.

The first option is that we put the contour on a flooring made of insulation - polystyrene foam, penofol or other suitable material. We cover the contour on top with a tree or other coating. The step by step process is as follows:

We carry out a thin rough screed;
We lay sheets of insulation with grooves for the highway;
We lay the line and perform pressure testing;
We cover the top with a substrate made of foamed polyethylene or polystyrene;
We put a top coat of laminate or other material with good thermal conductivity on top.

The second option looks like this:

We carry out a thin concrete screed;
We put a heater on the screed;
We lay out waterproofing on the insulation, on top of which we place the contour of the warm water floor;
At the top we fix it with a reinforcing mm and fill it with a concrete screed;
We put the finish coat on the screed.

The temperature is controlled by two thermometers- one shows the temperature of the coolant entering the line, the other - the temperature of the return flow. If the difference is between 5 and 10 degrees Celsius, then the design is working properly.

Methods for laying the contour of a warm water floor

When we carry out installation, the highway can be laid out in the following ways:

For spacious rooms with a simple geometric configuration, it is worth using the snail method. For rooms small size complex shape, it is more convenient and efficient to use the snake method.

These methods can, of course, be combined with each other.

depending on the diameter of the line and the size of the room. The smaller the laying step, the better and better the housing warms up, but on the other hand, then the costs for heating the coolant, materials and installation structures increase significantly. The maximum step size can be 30 centimeters, but this value cannot be exceeded, otherwise the human foot will feel the temperature difference. There will be more heat loss near the outer walls, so the line laying step in these places should be less than in the middle.

The material for the manufacture of pipes is polypropylene or cross-linked polyethylene. If you are using polypropylene pipes, it is worth choosing an option with fiberglass reinforcement, since polypropylene tends to expand when heated. Polyethylene pipes behave well when heated and do not require reinforcement.

Water floor contour length

The length of the water circuit of the warm floor is calculated by the formula:

L=S\N*1,1, where

L - loop length,

S is the area of the heated room,

N - laying step length,

1.1 - pipe safety factor.

There is such a thing as the maximum length of the water loop - if we exceed it, loopback effect may occur. This is a situation when the coolant flow is distributed in the line in such a way that a pump of any power cannot set it in motion. The maximum loop size directly depends on the diameter of the pipe. As a rule, it is in the range from 70 to 125 meters. The material from which the pipe is made also plays a role here.

The question arises - what to do if one circuit of the maximum size is not able to heat the room? The answer is simple - we are designing a double-circuit floor.

Installation of a system where a two-circuit design option is used is no different from where one circuit is used. If the double-circuit option does not cope with the task, add the required number of loops, as much as possible to connect to a home-made polypropylene floor heating manifold.

The question arises - how much one circuit in size can differ from another in a design where there are more than one. In theory, the installation of a warm water floor structure assumes an equal distribution of the load, and therefore it is desirable that the length of the loops be approximately the same. But this is not always possible, especially if one collector serves several rooms. For example, the size of the loop in the bathroom will be clearly smaller than in the living room. In this case, the balancing fittings equalize the load along the contours. The variation in size in such cases is allowed up to 40 percent.

Installation of a warm water heating structure is allowed only in those parts of the room where there will be no overall furniture. This is due to the excessive load on it and the fact that in these areas it is impossible to ensure proper heat transfer. This space is called the usable area of the room. Depending on this area, as well as on the laying step, the number of design loops depends.

15 cm - up to 12 m 2;
20 cm - up to 16 m 2;
25 cm - up to 20 m 2;
30 cm - up to 24 m 2.

Underfloor heating installation - what else you need to know

When installing a water heating system, you should know a few more important things.

One loop should heat one room - it should not be stretched over two or more rooms.
One pump must serve one manifold group.
When calculating multi-storey buildings served by one collector, the coolant flow should be distributed, starting from the upper floors. In this case, the heat loss of the floor on the second floor will serve as additional heating for the premises of the first floor.
One collector is able to serve up to 9 loops with a loop length of up to 90 m, and with a length of 60-70 m - up to 11 loops.

Conclusion

Warm water heating systems are extremely convenient and efficient in operation. It is quite possible to install them on your own. An important role is played by the correctness of calculations, accuracy and thoroughness in the performance of all work, taking into account all the features and details. After carrying out all the work, you will be able to enjoy the warmth and comfort of a well-heated room with a floor that is so pleasant to walk barefoot on.