How to calculate the length of the pipe for a warm floor. Correct warm water floor in a private house Water heated floors in one contour

Warm floor perfect solution for the improvement of their homes. 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, from the number of loops and their length, the total length of the pipe is added. It is clear that the longer the pipe in the same volume, the warmer the floor. In this article, we will talk about the restrictions on the length of one contour of the 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.

The 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 it may simply not be able to cope with the task assigned to it. Resistance calculation consists of many parameters. Conditions, styling parameters. The material of the pipes used. There are three main ones: loop length, number of bends and thermal load on it.

It is worth noting that the heat load increases with increasing 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 done, also increases. The hydraulic resistance of our system. There are also restrictions on it. 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 the very weak point... The constriction can cause a blockage of the flow in the heating medium. Pipes made of different materials have different expansion coefficients. For example, in polymer pipes the expansion coefficient is very high. All these parameters must be taken into account when installing a warm floor.

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

Optimum pipe length

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

The table shows the optimal dimensions of the underfloor heating that are suitable for all modes of thermal expansion of pipes in various modes of operation.

Note: B residential buildings 16 mm pipe is enough. A larger diameter should not be used. This will lead to unnecessary waste on energy.

Underfloor heating is one of the most efficient and cost effective heating methods. Judging from the point of view of operating costs, then a water "warm floor" looks preferable, especially if the house already has a water heating system. Therefore, despite the rather high complexity of installation and debugging of water heating, it is often chosen.

Work on a water "warm floor" begins with its design and calculations. And one of critical parameters will become the length of the pipes in the circuit to be laid. The point here is not only, and not so much in the cost of material - it is important to ensure that the length of the circuit does not exceed the permissible maximum values, otherwise the operability and efficiency of the system is not guaranteed. The calculator for calculating the length of the contour of a water-heated floor, located below, can help with the necessary calculations.

Several necessary explanations for working with the calculator are given below.

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 that is used for the warm floor. Almost every country house has its own heating 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 it is problematic to install an additional boiler.

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

How can you install underfloor heating?

There are several ways to install underfloor heating. For example, you can consider 2 ways.

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

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

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

Underfloor heating concrete installation

Despite the fact that it takes longer to install underfloor heating in this way, it is more popular. The underfloor heating pipe is selected depending on the materials. It is worth noting that the price of a pipe will also depend on the material from which it is made. With this method, the pipe is laid along the contour. After laying the pipe, it is poured concrete screed without additional thermal insulation materials.

Calculation and installation of underfloor heating

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.

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 should be noted that these dimensions are indicated for several reasons.

Due to the fact that the 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. Choosing the optimal size of the squares - you distribute energy and water more efficiently through the pipes.

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 (bends), leaving one source, gradually rounding towards the middle;
Corner snake. Two pipes come out from one corner: the first pipe starts the snake, the second ends.

Depending on which method of pipe laying 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?

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

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

Laying step

In order for a person's feet not to feel the difference between the floor areas, 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 a warm floor

On average, 5 running meters of pipe are required per 1 m2. This method is easier in determining 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 = S / N * 1.1, where:

S is the area of the room.
N - Laying step.
1.1 - stock of the pipe 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 ( effective area): 15 m2;
Distance from floor to collector: 4 m;
Underfloor heating installation step: 15 cm (0.15 m.);
Calculations: 15 / 0.15 * 1.1 + (4 * 2) = 118 m.

How long should the contour of a water-heated floor be?

It is necessary to calculate these parameters 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 water floor heating circuit should not exceed 100 meters. Optimal length for such a pipe - 75-80 meters.

For XLPE pipes with a diameter of 18 mm, the length of the contour on the surface for underfloor heating should not exceed 120 meters. In practice, this length is 90-100 meters.

For metal-plastic pipe with a diameter of 20 mm, the maximum length of underfloor heating 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 the room. It is worth noting that from what material the pipes are made and how they are laid on the surface, their durability and quality of work depend. 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 should be done in several stages.

Installation of thermal insulation

At this stage, preparatory work, the floor is cleaned and a layer of thermal insulation is laid. Foam can be used as thermal insulation. Foam plastics are laid on the sub-floor. 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, a layer of waterproofing must be installed. A polyethylene film is suitable as waterproofing. Polyethylene film fixed to the walls (near the plinth), and from above the floor is reinforced with mesh.

Laying and securing pipes

Next, you can lay pipes for the warm floor. Once you have calculated and selected the pipe laying scheme, this process does not take you much time. When laying pipes, they must be fixed on reinforcement mesh special braces or clamps.

Crimping

Pressing is almost the last stage of installing 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 the pipes.

Pouring with concrete mortar

All floor pouring work is carried out under pressure. It should be noted that the thickness of the concrete layer should not exceed 7 cm.

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

Manifold cabinet and installation

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

A manifold is a device that maintains pressure in 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 the installation of a manifold cabinet, at the same time, there are several recommendations.

It is also not recommended to install the collector cabinet too high, as eventually the water circulation may be uneven. The optimum height for installing the cabinet is 20-30 cm above the bare floor.

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

The collector cabinet must have an air outlet on top. It is strictly forbidden to lay underfloor heating under furniture. Firstly, because it will lead to deterioration of the materials from which the furniture is made. Secondly, it can lead to fire. Highly flammable materials can easily catch fire if the room is hot. Thirdly, the heat from the floor must constantly rise up, the furniture prevents this, thus, the pipes heat up faster and can deteriorate.

The choice of a collector is necessary 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;
Heat resistance.

Buy pipes with a medium diameter. If the diameter of the pipe is too large, the circulation of water will take a very long time, and reaching the middle or end (depending on the method of installation) the water will cool down, the same situation will occur with a pipe with a small diameter. That's why the best option there will be pipes with a diameter of 20-40 mm.

Before calculating a warm floor, consult with those who have already done this. The calculation of the area and number of pipes is important stage preparation 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 the 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 the 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 warm floor correctly, it will serve you for many years. If you have any questions, it is better to ask them to the expert of our website or contact the specialists who will qualitatively, quickly and reliably improve and prepare your room for the installation of a warm floor.

One of the conditions for the implementation of high-quality and correct heating of a room using 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 heat for the heated room and floor covering.

Required data for calculation

The efficiency of the heating system depends on a correctly laid circuit.

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

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

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

Based on the listed data, it is possible to perform the correct calculation of the length of the underfloor heating circuit and thereby ensure a comfortable temperature regime in a room with minimal cost to pay for energy supply.

Floor temperature

The temperature on the surface of the floor, made with a water heating device under it, depends on the functional purpose of the room. Its values should be no more than those indicated in the table:

Compliance with the temperature regime in accordance with the above values will create a favorable environment for the work and rest of the people in them.

Pipe laying options used for underfloor heating

Underfloor heating installation options

The laying pattern can be done with a regular, double and angled 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.

V large rooms complex configuration is best done with a snail. Indoors small size and having 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 the pipe is laid out with a step of more than 25 cm, the person's foot will feel the temperature difference between and immediately above them.

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

Permissible contour length

The length of the circuit must be matched to the pipe diameter

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 supplied to them per unit of 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, the 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 practical experience, you can adhere to the following recommended sizes:

Less than 100 m can be a loop made of 16 mm diameter reinforced plastic pipe. For reliability optimal size is 80 m.
No more than 120 m is assumed to be a maximum loop length of 18 mm of XLPE pipe. Experts try to install a circuit with a length of 80-100 m.
No more than 120-125 m is considered an acceptable loop size for metal-plastic with a diameter of 20 mm. In practice, they also try to reduce this length to ensure sufficient reliability of the system.

For more precise definition the size of the loop length for the warm floor in the room in question, in which there will be no problems with the circulation of the coolant, it is necessary to perform calculations.

Applying multiple paths of different lengths

The device of the underfloor heating system provides for the implementation of several circuits. Of course, it is ideal when all the loops are the same length. In this case, adjustment and balancing of the system is not required, but it is almost impossible to implement such a pipe routing scheme. Detailed video for calculating the length of the water circuit, see this video:

For example, it is necessary to carry out a warm floor 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 impractical 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, you can apply a requirement 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 for by increasing or decreasing the diameter of the pipe and changing the pitch of its laying.

Possibility 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 heating circuits, the diameter and material of the pipes used, the area of the heated rooms, the material of the enclosing structures and on many other various indicators.

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

Determining the size of the buttonhole

The size of the loop depends on total area premises

Having collected all the initial data, having considered possible options creating a heated floor and determining 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 the 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.

To the result, add the length of the pipeline, which will need to be laid from the collector to warm floor and back. The answer to the key questions of organizing a warm floor, see this video:

You can determine the length of the loop, laid with a step of 20 cm in a room with an area of 10 m2, located at a distance of 3 m from the collector, by following these steps:

10 / 0.2 * 1.1 + (3 * 2) = 61 m.

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

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

To correctly determine the pipe length of several heating circuits for a large number premises supplied from one collector, it is necessary to involve a design organization.

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

The device of warm water floors in a private house has many nuances and others important points to consider. In this article I will show you how to make the right warm water floor. I will describe the main points that installation organizations and customers overlook.

Content

1.Thickness of the screed for warm water floors

Pipe manufacturers are misleading people by suggesting a screed height of 25, 30 or 35 mm above the pipe. Installers are confused about the readings. As a result, the warm floor does not work correctly.

Remember: According to SP 29.13330.2011 p 8.2 - optimal thickness the cement screed must be at least 45 mm above the pipeline.

Simply put, if we use the RAUTHERM S 17x2.0 pipeline with a height of 17 mm, then a screed should be 45 mm above the pipe. Minimum thickness screeds for a warm floor above the insulation are 62 mm.

With a decrease in the thickness of the screed, the risk of cracks and chips increases. Underfloor heating pipes expand and contract under the influence of temperatures. With the height of the screed, we compensate for such temperature deformations. In practice, reducing the height of the screed leads to a feeling of temperature changes on the floor surface. One part of the floor is hotter, the other colder.

Some of my Customers want to be on the safe side and increase the maximum screed thickness to 80 mm, thereby greatly increasing the inertia of the system and heat consumption. The warm floor reacts with a great delay to changes in the air temperature in the room and consumes more heat to warm up additional centimeters of the screed. By the way, for the underfloor heating system, I recommend using a concrete grade of at least M-300 (B-22.5).

2.Insulation for warm water floor

In the underfloor heating system, only 1 of 3 types of insulation is used: extruded polystyrene foam with a density of more than 35 kg / m 2... When purchasing, be sure to check the type and density of the insulation. It is important!

Regular foam is not suitable for underfloor heating. It is very brittle, has a lower density than expanded polystyrene. The use of polystyrene in the underfloor heating system will cause the screed to sag. It is prohibited to use polystyrene as insulation.

Foamed insulation will not withstand the weight of the screed and will shrink from 10 cm to 1-2 cm. Sometimes installers advise expanded clay backfills instead of insulation for a warm floor. The option is working, but it significantly increases the load on the floors. Expanded clay is 12 times heavier than expanded polystyrene, and 5 times worse retains heat. Weight of 40 mm expanded clay backfill - 3.7 kg / m 2.

The task of the insulation in the underfloor heating system is not so much in thermal insulation as in compensating for the temperature expansion of pipes. The pipe is pressed into the insulation under the influence of temperature and does not deform the screed.

The underfloor heating cake is determined by the thickness of the insulation. The height of the insulation must be at least 50 mm in private houses. V interfloor ceilings apartments often mount a warm floor on a foil substrate - multi-foil without using a full layer of insulation.

3. Expansion joint in the floor screed

The expansion joint in the floor screed is used in rooms with an area of more than 40 m 2 where one of the sides of the room is more than 8 m.

In such rooms, the distribution of the contours of the warm floor is carried out depending on the placement of expansion joints. The expansion joint must not cross the underfloor heating loops and can only pass through the supply pipes.

At the intersection of expansion joints, pipes are laid in a corrugated tube-sleeve 1 meter long. Division of the room expansion joints starts from the corners of the room, places of narrowing and columns.

4.Floor covering for underfloor heating

The floor covering has a direct effect on heat dissipation and system performance. You can make a mistake with the thickness of the insulation, the screed, the laying step, but the mistake in choosing the floor covering will be fatal.

In I have already given calculations of why the warm floor cannot be used for heating. AND main reason- all kinds of shelters, carpets, sofas, furniture.

For example: Ceramic tiles give off heat 7 times better than laminate and 20 times better than any textile flooring.

In most cases, the porcelain stoneware coating compensates for mistakes with the choice of the thickness of the insulation, the screed, the wrong pipe laying step and much more. Porcelain stoneware gives off heat 2.5 times better than ceramic tile, 15 times better than polymer flooring and 17 times better than laminate.

When choosing a floor covering for underfloor heating, ask for a certificate marked "underfloor heating". This means that the material is certified for use with a warm water floor. Otherwise, if the cover is not selected correctly, The floor shrinks and smells.

5. Pipe for warm water floor

The warm floor does not allow joints and couplings. The underfloor heating loops are laid in a single piece of pipe. Therefore, the pipe is sold in coils of 60, 120 and 240 meters. Polypropylene pipes, pipes with threaded, coupled connections in underfloor heating systems for installation in a screed are strictly prohibited!

I am often asked which pipe to choose for a warm water floor. Cross-linked polyethylene is used as a material for underfloor heating pipes. I recommend 3 brands of underfloor heating pipe manufacturers for installation: Uponor - pePEX pipe, Rehau - Rautherm S, STOUT - PE-Xa / EVOH

The PEX pipe for underfloor heating is more plastic than its counterpart for heating.

The calculation of pipes for a warm water floor is reduced to determining the length of the circuit, the diameter and the pitch of the pipe, depending on the hydraulic balancing of the circuits.

The maximum length of the underfloor heating circuit should not exceed 80 meters. This pipe length corresponds to the maximum area of one underfloor heating circuit - 9 m 2 with a step of 150 mm, 12 m 2 - with a step of 200 mm, or 15 m 2 with a laying step of 250 mm.

At the same time, the minimum length of the underfloor heating circuit should be more than 15 meters, which corresponds to a floor area of 3 m 2. This requirement is very important for small bathrooms and bathrooms, where customers are trying to make a separate circuit, and then wonder why the warm floor is either hot or completely cold. The underfloor heating thermostat for such circuits works in jerks and quickly fails.

The diameter of the pipe for a warm water floor is determined in a complex manner for each collector cabinet, based on the requirements for a pressure drop in the circuit - no more than 12-15 kPa and a surface temperature - no more than 29 ° C. If one contour of the underfloor heating turns out to be significantly longer than the other, then we can balance such contours by changing the diameter of the pipe.

For example, our warm floor consists of 5 circuits 80 meters long, and 1 circuit - only 15 meters. Therefore, in a 15-meter circuit, we have to significantly narrow the pipe diameter so that the pressure loss in it is comparable to that of an 80-meter circuit. As a result: we mount 5 circuits with a diameter of 20 mm, and a 12-meter circuit - with a 14 mm pipe. To calculate the underfloor heating system, they usually contact me.

6.Thermostat for a water heated floor

The room thermostat in the underfloor heating system can be controlled both "by air" in the room, and "by water" - with a floor sensor. There are combined thermostats on sale that provide increased control accuracy, but also have increased requirements for the installation site.

A room thermostat for underfloor heating can control from 1 to 4 circuits, depending on the characteristics of a particular model. The thermostat is connected to the servo drives of the manifold assembly and regulates the power supply, due to which the servo drive opens and closes, regulating the water flow in the underfloor heating circuit.