Warm floor perfect solution to improve your home. The floor temperature directly depends on the length of the heated floor pipes hidden in the screed. The pipe in the floor is laid in loops. In fact, the total length of the pipe is determined by 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 heated floor circuit.

Approximate design characteristics for pipes with a diameter of 16 and 20 mm are: 80-100 and 100-120 meters, respectively. These data are provided as approximate estimates. Let's take a closer look at the installation and pouring process heated floors.

Consequences of exceeding the length

Let's figure out what consequences an increase in the length of the heated floor pipe can lead to. One of the reasons is an increase in hydraulic resistance, which will create 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, installation 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 increasing loop. The flow speed and hydraulic resistance also increase. There are restrictions on flow speed. It should not exceed 0.5 m/s. If we exceed this value, various noise effects may occur in the pipeline system. The main parameter for which this calculation is made also increases. Hydraulic resistance of our system. There are restrictions on it too. They amount to 30-40 kP per loop.

The next reason is that as the length of the heated floor pipe increases, the pressure on the walls of the pipe increases, causing this section to lengthen when heated. The pipe located in the screed has nowhere to go. And it will begin to narrow at its weakest point. The narrowing can cause blockage of the flow in the coolant. Pipes made from different materials have different expansion coefficients. For example, at polymer pipes the expansion coefficient is very high. All these parameters must be taken into account when installing a heated floor.

Therefore, it is necessary to fill the heated floor screed with pressed pipes. Pressure better with air with a pressure of approximately 4 bar. This way, when you fill the system with water and start heating it, the pipe in the screed will have room to expand.

Optimal pipe length

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

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

One of the conditions for the implementation of high-quality and proper heating The purpose of a room using a heated 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 floor covering.

Required data for calculation

To maintain a given 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 consists 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,
• 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 listed data, you can correctly calculate the length of the heated floor circuit and thereby ensure comfortable temperature regime indoors with minimal energy costs.

Floor temperature

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

Pipe laying options used for heated floors

The laying pattern can be made 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 like a snake, and then the middle part - like a snail.

IN large rooms For complex configurations, it is better to lay them in a snail shape. In rooms of small size and having a variety of complex configurations snake laying is used.

Pipe distance

The pipe laying pitch is determined by calculation and usually corresponds to 15, 20 and 25 cm, but no more. When laying pipes at intervals of more than 25 cm, a person’s foot will feel the temperature difference between and directly above them.

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

Allowable contour length

This 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 liquid that is supplied to them per unit time.

When installing a heated floor, situations often occur when the circulation of the coolant in a separate loop is disrupted, which cannot be restored by any pump; water is blocked 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:

1. Less than 100 m can be a loop made of metal plastic pipe with a diameter of 16 mm. For reliability, the optimal size is 80 m.
2. No more than 120 m is the maximum length of the contour of an 18 mm pipe made of cross-linked polyethylene. Experts try to install a circuit 80-100 m long.
3. 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.

To more accurately determine the size of the loop length for a heated floor in the room in question, in which there will be no problems with coolant circulation, it is necessary to perform calculations.

Application of multiple contours of different lengths

For example, it is necessary to install a heated floor system in several rooms, one of which, say a bathroom, has an area of ​​4 m2. This means that heating it will require 40 m of pipe. It is impractical to arrange 40 m loops in other rooms, whereas 80-100 m loops 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 loop lengths can be compensated by increasing or decreasing the diameter of the pipe and changing the pitch of its installation.

Possibility of connection to one unit 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 ​​the heated premises, the material of the enclosing structures and many other various indicators.

Such calculations must be entrusted to specialists who have knowledge and practical skills in carrying out such projects.

Loop size determination

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

To do this, you need 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.

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

In this room it is necessary to lay 61 m of pipe, forming a thermal circuit, to ensure the possibility of high-quality heating of the floor covering.

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

To correctly determine the pipe length of several heating circuits for large quantity premises powered 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 many different factors on which uninterrupted water circulation, and therefore high-quality floor heating, depends.

Optimal length of the heated floor contour
One of the conditions for high-quality and proper heating of a room using a heated floor is the optimal length of the heated floor circuit.

Folk wisdom calls for measuring seven times. And you can't argue with that.

In practice, it is not easy to realize what has been repeatedly replayed in your head.

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

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

Pipe location

The underfloor heating system includes a considerable list of elements. We are interested in tubes. It is their length that defines the concept “ maximum length warm water floor." They must be laid taking into account the characteristics of the room.

From this we get four options, known as:

If you do correct styling, then each of the listed types will be effective for heating the room. The length of the pipe and the volume of water may (and most likely will) be different. 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 water heated floor circuit. Another parameter is diameter. Pipes with a diameter of 2 cm are mainly used.

We also take into account the distance from the pipes to the wall. Here they recommend laying within 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 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:

1. Let’s say our room is 5 meters long and 4 meters wide.
2. Laying the pipeline of our system always starts from the smaller side, that is, from the width.
3. To create the base of the pipeline, we take 15 pipes.
4. A gap of 10 cm remains near the walls, which then increases by 5 cm on each side.
5. 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 = 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 heated floor circuit? What to do if the room requires, for example, 130 or 140-150 m of pipe? The solution is very simple: you will need to make more than one circuit.

The main thing in the operation of a water heated floor system 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 water-heated floor circuit should not exceed this figure. 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 for the difference to 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 heated floor circuit

To determine this parameter we must consider:

• hydraulic resistance,
• pressure loss in a specific circuit.

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

In the installation of heated floors there is a concept - the so-called effect. locked loop. We are talking about a situation where circulation through the loop will be impossible, regardless of the power of the pump. This effect is 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, proven by practice:

1. A 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
2. A contour of 120 m is the limit for an 18 mm cross-linked polyethylene pipe. However, it is better to limit yourself to a range of 80-100 m
3. With a 20 mm plastic pipe you can make a contour of 120-125 m

Thus, the maximum pipe length 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 one is better to choose flooring for warm water floor:

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

Are two identical ones necessary/possible?

Naturally, the ideal situation would be when the loops are the same length. In this case, no adjustments or searches for balance will be needed. But this is mostly in theory. If you look at practice, it turns out that it is not even advisable to achieve such an equilibrium in a warm water floor.

The fact is that it is often necessary to lay heated floors in a facility consisting of several rooms. One of them is emphatically 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, dividing it into tiny sections?

Since this is not advisable, we approach another question: how not to lose pressure. And for this purpose, elements such as balancing valves have been created, the use of which consists in equalizing pressure losses along the circuits.

Again, you can use calculations. But they are complex. From the practice of carrying out work on installing a warm water floor, we can safely say that the variation in the size of the contours is possible within 30-40%. In this case, we have every chance to get the maximum effect from using 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, in fact, needs to be more specific. 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 coolant passing through the unit per unit of time (calculation is in m3 per hour).

We need to look at the node's data sheet, which shows the maximum throughput factor. If we carry out the calculations, we will get the maximum figure, but we cannot count on it.

One way or another, the device indicates the maximum number of circuit connections - usually 12. Although, according to calculations, we can get 15 or 17.

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

We saw that installing a warm water floor is a very troublesome task. Especially in the part where we're talking about about the length of the contour. Therefore, it is better to contact specialists so as not to redo a not entirely successful installation, which will not bring the effectiveness that you expected.

Laying and calculating the maximum length of the water heated floor circuit
The article contains detailed information about the maximum length of the water heated floor circuit, the location of the pipes, optimal calculations, as well as the number of circuits with one pump and whether two identical ones are needed.

Laying heating pipes under the floor covering is considered one of best options heating a house or apartment. They consume fewer resources to maintain the specified temperature in the room, exceeding standard wall radiators in terms of reliability, they evenly distribute heat in the room, rather than creating separate “cold” and “hot” zones.

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

Laying options

Builders use four common pipe laying patterns, each of which is better suited for indoor use. various shapes. The maximum length of the heated floor contour largely depends on their “pattern”. This:

• "Snake". Sequential laying, where the hot and cold lines follow each other. Suitable for elongated rooms divided into zones of different temperatures.
• "Double Snake" Used in rectangular rooms, but without zoning. Provides uniform heating of the area.
• "Corner Snake". Serial system for room with equal length walls and the presence of a low heating zone.
• "Snail". Double laying system, suitable for close to square shaped rooms without cold spots.

The chosen installation 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 will need the following formula:

The values ​​are indicated 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 heated floor contour obtained as a result of calculations is additionally increased by 5%, which includes a small margin for leveling out errors, changing the bending radius of the pipe and connecting to fittings.

As an example of calculating the maximum length of a pipe for a heated 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, we get the following:

5% is added to the result, which is 4.94 m and the recommended length of the water heated floor circuit increases to 103.74 m, which is 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, the number of circuits in the room and the power of the pump, which is responsible for circulating the coolant.

In apartments and houses with medium-sized 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 a water heated floor circuit with 16 pipes is 90-100 m, depending on the choice of pipe material. It is not recommended to exceed this figure, because the so-called “locked loop” effect may occur when, regardless of the power of the pump, 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 small area or part of a large one, it is irrational to stretch the outline over several rooms.
• One pump per collector, even if the declared power is enough to provide two “combs”.
• With a maximum length of underfloor heating pipe of 16 mm per 100 m, the collector is installed on no more than 9 loops.

If the maximum length of the heated floor loop 16 pipes exceeds the recommended value, then the room is divided into separate circuits, which are connected into one heating network by a manifold. To ensure uniform distribution of coolant throughout the system, experts advise not to exceed the difference between individual loops of 15 m, otherwise the smaller circuit will heat up much more than the larger one.

But what to do if the length of the heated floor contour of a 16 mm pipe differs by a value that exceeds 15 m? Balancing fittings will help, changing the amount of coolant circulating through each loop. With its help, the difference in lengths can be almost two times.

Room temperature

Also, the length of the heated floor contours for pipe 16 affects the heating level. To maintain a comfortable indoor environment, a certain temperature is needed. To do this, the water pumped through the system is heated to 55-60 °C. Exceeding this indicator may have a detrimental effect on the integrity of the material. engineering communications. 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 of 16 mm in 90-100 m, the difference at the “input” and “output” of the mixing boiler should not exceed 5 °C, a different value indicates heat loss on the heating main.

Maximum length of the water heated floor circuit: installation and calculation optimal value
Laying heating pipes under the floor covering 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, and evenly distribute heat in the room rather than creating separate

The main argument in favor of the "warm floor" system is the increased comfort of a person's stay in the room, when the quality heating device the entire floor surface protrudes. The air in the room warms up from the bottom up, while at the surface of the floor it is slightly warmer than at a height of 2-2.5 m.

In some cases (for example, when heating shopping malls, swimming pools, gyms, hospitals), underfloor heating is the most preferable.

To the disadvantages of systems underfloor heating include the relatively high cost of equipment compared to radiator systems, as well as increased requirements for the technical literacy of installers and the quality of their work. Using quality materials and following the installation technology of a well-designed water underfloor heating system, no problems arise during its subsequent operation.

The heating boiler operates on radiators in 80/60 °C mode. How to properly connect a "warm floor"?

To obtain the design temperature (usually not higher than 55 °C) and the specified coolant flow rate in the “warm floor” circuit, pumping mixing units. They form a separate low-temperature circulation circuit into which hot coolant from the primary circuit is mixed. The amount of coolant added can be set either manually (if the temperature and flow rate in the primary circuit are constant) or automatically using thermostats. All the benefits of a “warm floor” can be fully realized by pumping and mixing units with weather compensation, in which the temperature of the coolant supplied to the low-temperature circuit is adjusted depending on the outside air temperature.

Is it allowed to connect a “warm floor” to the central heating or hot water system of an apartment building?

This depends on local laws. For example, in Moscow, the installation of heated floors from communal water supply and heating systems is excluded from the list of permitted types of re-equipment (Moscow Government Decree No. 73-PP of February 8, 2005). In a number of regions, interdepartmental commissions deciding the issue approvals for the installation of a "warm floor" system require additional expertise and calculated confirmation that the installation of a "warm floor" will not lead to a disruption in the operation of common house facilities engineering systems(See "Rules and Regulations" technical operation housing stock", clause 1.7.2).

From a technical point of view, connecting a “warm floor” to a central heating system is possible provided that a separate pumping and mixing unit is installed with limited pressure returned to the house system coolant. In addition, if there is an individual in the house heating point equipped with an elevator (jet pump), the use of plastic and metal-plastic pipes in heating systems is not allowed.

What material is better to use as a floor covering in a "warm floor" system? Can parquet floors be used?

The “warm floor” effect is best felt with floor coverings made of materials with a high thermal conductivity coefficient ( ceramic tile, concrete, self-leveling floors, baseless linoleum, laminate, etc.). If carpet is used, it must have a “suitability mark” for use on a warm substrate. Others synthetic coatings(linoleum, relin, laminated boards, plastic compound, PVC tiles, etc.) must have a “no sign” of toxic emissions at elevated base temperatures.

Parquet, parquet boards and boards can also be used as a “warm floor” covering, but the surface temperature should not exceed 26 °C. In addition, the mixing unit must include a safety thermostat. The moisture content of natural wood flooring materials should not exceed 9%. Work on laying parquet or plank flooring is permitted only when the room temperature is not lower than 18 ° C and 40-50 percent humidity.

What should be the temperature on the surface of the “warm floor”?

The requirements of SNiP 41-01-2003 “Heating, ventilation and air conditioning” (clause 6.5.12) regarding the surface temperature of the “warm floor” are given in the table. It should be noted that foreign regulations allow several large values surface temperatures. This must be taken into account when using calculation programs developed on their basis.

How long can the pipes of the "warm floor" circuit be?

The length of one loop of a “warm floor” is dictated by the power of the pump. If we talk about polyethylene and metal-plastic pipes, then it is economically feasible that the length of a pipe loop with an outer diameter of 16 mm does not exceed 100 m, and with a diameter of 20 mm - 120 m. It is also desirable that the hydraulic pressure loss in the loop does not exceed 20 kPa. The approximate area occupied by one loop, subject to these conditions, is about 15 m2. At larger area collector systems are used, and it is desirable that the length of the loops connected to one collector be approximately the same.

What should be the thickness of the thermal insulation layer under the "warm floor" pipes?

The thickness of the thermal insulation, which limits heat loss from the "warm floor" pipes in the "downward" direction, must be determined by calculation and largely depends on the air temperature in the design room and the temperature in the underlying room (or ground). In most Western calculation programs, downward heat loss is assumed to be 10% of the total heat flow. If the air temperature in the design and underlying rooms is the same, then this ratio is satisfied by a layer of polystyrene foam 25 mm thick with a thermal conductivity coefficient of 0.035 W/(mOK).

Which pipes are best used for installing a "warm floor" system?

Pipes for underfloor heating must have the following properties: flexibility, allowing the pipe to be bent with a minimum radius to ensure the required installation pitch; ability to maintain shape; low coefficient of resistance to coolant movement to reduce the power of pumping equipment; durability and corrosion resistance, since access to pipes during operation is difficult; oxygen-tight (like any pipeline heating system). In addition, the pipe should be easy to process simple tool and have a reasonable price.

The most widespread systems are “warm floors” made of polyethylene (PEX-EVOH-PEX), metal-plastic and copper pipes. Polyethylene pipes are less convenient to use because they do not retain their given shape, and when heated they tend to straighten out (“memory effect”). Copper pipes, when embedded in a screed, must have a coating polymer layer to avoid alkaline effects, and this material is also quite expensive. Metal-plastic pipes most fully satisfy the requirements.

Is it necessary to use a plasticizer when pouring a “warm floor”?

The use of a plasticizer makes it possible to make the screed more dense, without air inclusions, which significantly reduces heat losses and increases the strength of the screed. However, not all plasticizers are suitable for this purpose: most of those used in construction are air-entraining, and their use, on the contrary, will lead to a decrease in the strength and thermal conductivity of the screed. For underfloor heating systems, special non-air-entraining plasticizers based on fine flaky particles are produced mineral materials with low friction coefficient. As a rule, the plasticizer consumption is 3-5 l/m3 of solution.

What is the point of using aluminum foil coated insulation?

In cases where "warm floor" pipes are installed in air gap(for example, in floors along joists), foiling the thermal insulation allows you to reflect most of the downward radiant heat flow, thereby increasing the efficiency of the system. The same role is played by foil when constructing porous (gas or foam concrete) screeds.

When the screed is made of a dense cement-sand mixture, foiling the thermal insulation can only be justified as additional waterproofing - the reflective properties of the foil cannot manifest themselves due to the absence of an air-solid boundary. It must be borne in mind that the layer of aluminum foil poured cement mortar, must have a protective coating of polymer film. Otherwise, aluminum may be destroyed under the influence of the highly alkaline solution environment (pH = 12.4).

How to avoid cracking of underfloor heating screed?

The reasons for the appearance of cracks in the “warm floor” screed may be low strength of the insulation, poor compaction of the mixture during installation, lack of plasticizer in the mixture, or too thick screed (shrinkage cracks). Should be adhered to following rules: the density of the insulation (expanded polystyrene) under the screed must be at least 40 kg/m3; the screed solution must be workable (plastic), the use of a plasticizer is mandatory; to avoid the appearance of shrinkage cracks, polypropylene fiber must be added to the solution at the rate of 1-2 kg of fiber per 1 m3 of solution. For heavily loaded floors, steel fiber is used.

Is waterproofing required when installing underfloor heating?

If the architectural and construction part of the project does not provide for a vapor barrier device, then with the “wet method” of installing a “warm floor” system on the floors, it is recommended to lay a layer of glassine over the leveled floor. This will help prevent laitance from leaking through the ceiling while pouring the screed. If the project provides for an interfloor vapor barrier, then additional waterproofing is not necessary. Waterproofing in wet rooms (bathrooms, lavatories, showers) is installed in the usual manner on top of the “warm floor” screed.

What should be the thickness of the damper tape installed around the perimeter of the room?

For rooms with a side length of less than 10 m, it is sufficient to use a 5 mm thick seam. For other rooms, the calculation of the seam is carried out according to the formula: b = 0.55 o L, where b is the thickness of the seam, mm; L - length of the room, m.

What should be the step for laying the pipes of a “warm floor” loop?

The pitch of the loops is determined by calculation. It must be taken into account that a loop pitch of less than 80 mm is difficult to implement in practice due to the small bend radius of the pipe, and a pitch of more than 250 mm is not recommended, as it leads to noticeable uneven heating of the “warm floor”. To facilitate the task of choosing a loop pitch, you can use the table below.

Is it possible to install heating only using a “warm floor” system, without radiators?

To answer this question in each specific case, it is necessary to carry out a thermal engineering calculation. On the one hand, the maximum specific heat flux from a “warm floor” is about 70 W/m2 at a room temperature of 20 °C. This is enough to compensate for heat losses through enclosing structures made in accordance with thermal protection standards.

On the other hand, if we take into account the heat costs for heating the outside air required by sanitary standards (3 m3/h per 1 m2 of living space), then the power of the “warm floor” system may be insufficient. In such cases, it is recommended to use edge zones with increased surface temperatures along the external walls, as well as the use of “warm wall” sections.

How long after pouring the screed can the “warm floor” system be started?

The screed must have time to acquire sufficient strength. Three days later in natural conditions After hardening (without heating), it gains 50% strength, after a week - 70%. Full strength gain to the design grade occurs after 28 days. Based on this, it is recommended to start the “warm floor” no earlier than three days after pouring. You also need to remember that the “warm floor” system is filled with solution when the floor pipelines are filled with water under a pressure of 3 bar.

We continue to disassemble design of heated floors, started in the previous article, and now we will consider the main design recommendations.

What should the surface temperature of the heated floor be?

Actually, I already wrote about this in a separate article, but it would be worth repeating. Listed below maximum floor surface temperature limits for premises of various purposes:

• for living quarters and work rooms in which people mainly stand: 21...27 degrees;
• for living rooms and offices: 29 degrees;
• for lobbies, hallways and corridors: 30 degrees;
• for baths, swimming pools: 33 degrees
• for rooms where active activity takes place: 17 degrees
• in premises with limited presence of people (industrial premises) is allowed Maximum temperature floor 37 degrees.

In the edge zones up to 35 degrees.

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

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

The temperature difference of the coolant 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 difference in the temperature of 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 optimal temperature drop is 10 degrees. Recommended temperatures at the inlet/outlet loops: 55/45 degrees, 50/40 degrees, 45/35 degrees, 40/30 degrees.

If thermal power is used as a heat source pumping unit(although this is very rare), it is advisable to set 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 water heated floor 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;
• diameter 20 mm – 120 m.

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

Typically, one circuit heats one room. But if the area of ​​the room is large, the length of the circuit is longer than optimal, then it is better to make two circuits per room than to lay a pipe that is too long.

If during design and calculations you take one pipe diameter and then install another, then the hydraulics of the system will be different. So it is better and correctly 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 installed in a room, you should strive to ensure that their lengths are the same (the length of the circuit is 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 different areas. To lay the same number of meters of pipe in a smaller room as in a larger one, you need to do smaller step between turns.

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

At what step should the underfloor heating pipes be laid out?

The pitch (distance between adjacent turns of pipes) of pipe laying is from 15 to 30 cm (15, 20, 25, 30 cm - that is, not 21; 22.4; 27, etc., but with a step of 5 cm in the specified range 15-30 cm). Pipe laying pitches of 30, 35, 40, 45 cm are 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 thermal 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 increments of 100...150 mm. The same step may not be possible due to the need to bypass the plumbing and due to the cramped space in the room;
• in rooms where the floor will be covered with a material with good thermal conductivity ( tile, marble, porcelain stoneware) pipe laying pitch - 200 mm.

Attention! The 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 laid with a snake). Therefore, when laying with a snake, it is better and optimal to have a pitch of 150...200 mm. And in general, take note: despite any recommendations and clever justifications, make the pipe pitch in the edge zones 100 mm, and in the remaining 150 mm, and you will never go wrong.

A pitch of 300 mm will not provide 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. No need for 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, larger diameter pipes are not needed for a private home: they are optimal in terms of “ease of installation – price – coolant volume”.

Another pipe often used is 18 mm. However, you need to understand that a thicker pipe means extra costs, and not only for the pipe, but also for fittings and everything else.

Sometimes they lay a pipe with a diameter of 20 mm, without taking into account the characteristics. And in such a pipe the amount of water is already significantly greater, which is why heating will require more energy. And it’s difficult to install such a pipe: bending it for installation with a snake and a step of 150 mm is unrealistic, and larger step will not provide heat in the house, and the cost of coolant will be indecently decent. Such a pipe can be laid in some public buildings, With high ceilings, with a large number of people being there at the same time. There will be a thick screed poured in there! For a 16 mm pipe, the thickness of the screed is sufficient 50 mm from the top of the pipe. Up to 80 mm is allowed.

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 line - it doesn’t matter whether it is internal or external.

There are manifolds with an inch and a quarter thread, but these are 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 home.

It makes no sense to initially narrow or “widen” the diameters of the main pipes (i.e., supplying coolant from the boiler), but it makes sense to take the same diameter as the collector inlet, i.e. 1 inch. For 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 this is a diameter of 26 mm. For copper – 28 mm. This - standard options on the use of 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; To go 1 inch you will need an adapter).

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 designing underfloor heating

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

One circuit should be for one room (meaning, there is no need to get weird by laying out a loop, filling in the screed, and then dividing the room with a partition).

It is advisable to place the collector in the middle of the house. If this does not work, then the problem with the difference in loop lengths is solved by installing flow meters on the manifold: with their help, the uniform flow of coolant through loops of different lengths is regulated.

If the circuits are 90 m long (or even more), then a maximum of nine circuits can be “attached” to one collector. With loop lengths of 60...80 m, up to 11 loops can be mounted on one collector.

There is no need to “press” 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 all pipe lengths of underfloor heating loops, so please check when purchasing.

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

The thickness of the insulation on the first and ground floor not less than 50 mm (in reality, it depends on climate zone: what is good for the south does not work 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, even if the heat from the heated floor on the second floor also warms the first floor? Answer: if the floor is concrete, then insulation is installed so as not to heat the floor itself, because this is very expensive both in terms of money and time.

The maximum pressure loss in the circuit is 15 kPa (optimally 13 kPa). If the circuit has a pressure loss of more than 15 kPa, you need to reduce the coolant flow or divide the floor area in the room into several circuits. We’ll look at what this means in one of the following articles, when we perform calculations using a specific example.

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

The above requirements for design of heated floors will need to be taken into account when performing calculations for heated floors, when we do this in a special program. So, if these terms don’t mean anything to you yet, don’t worry, everything will fall into place in due time. However, I recommend making a note for yourself somewhere so that you can return to the information in this article when making calculations.

design of heated floors

Today it is difficult to imagine Vacation home no floor heating. Before you start installing heating, you need to calculate the length of the pipe that is used for the heated 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 warm floors 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 connect the heated floor to the heating system, and installing an additional boiler is problematic.

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

How can I install a heated floor?

There are several ways to install heated floors. For example, we can consider 2 methods.

Grazing. This floor has a various materials, for example 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 for pouring the screed and drying it.

Concrete. This type of 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 heated floor is a difficult task, so it is not recommended to carry out this process yourself. If there are no additional funds for workers, then you can install the floor yourself, but strictly following the installation instructions.

Concrete installation of heated floors

Despite the fact that it takes longer to lay heated floors this way, it is more popular. The pipe for underfloor heating 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. 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 heated floors

Before you begin installing the floor, you need to calculate required amount 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 circuit length required for a warm water floor should not exceed 120 meters. It is worth noting that these 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 square sizes, you distribute energy and water through the pipes more efficiently.

Once the room has been divided into parts, you can begin planning the shape of the pipe.

Methods for laying pipes for heated floors

There are 4 ways to lay the pipe:

• Snake;
• Double snake (fits into 2 pipes);
• Snail. The pipe is laid in 2 times (bends) coming from 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 it.

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 installation method should you choose?

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

If the room is long or small, then it is recommended to use a “snake”.

Laying step

In order for a person’s feet not to feel the difference between sections of the floor, it is necessary to adhere to a certain length between the pipes, at the edge this length should be approximately 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 walking on such a floor will be simply unpleasant.

Calculation of pipes for heated floors

On average, 5 linear meters of pipe are needed per 1 m2. This method is easier to determine how many pipes per m2 are needed to install a heated 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 – area of ​​the room.
• N – Laying step.
• 1.1 – pipe reserve 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 (usable area): 15 m2;
• Distance from floor to collector: 4 m;
• Step for laying heated floors: 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?

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 water-heated floor contour 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 heated floor should be approximately 100-120 meters, depending on the manufacturer.

It is recommended to select pipes for laying on the floor based on the area of ​​the 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 begin installing the heated floor. This needs to be done in several stages.

Installation of thermal insulation

At this stage, preparatory work, the floor is cleared and a layer of thermal insulation is laid. Polystyrene foam can act as thermal insulation. Layers of foam plastic 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 has been laid, it is necessary to lay a layer of waterproofing. Polyethylene film is suitable as waterproofing. Polyethylene film it is fixed to the walls (near the baseboard), and the floor is reinforced with mesh on top.

Laying and securing pipes

Next, you can lay the pipes for the heated floor. Once you have calculated and chosen a pipe laying scheme, this process will not take you much time. When laying pipes, they must be secured to the reinforcing mesh with special braces or clamps.

Crimping

Crimping is practically final stage installation of heated floors. Pressure testing must be carried out within 24 hours at operating pressure. Thanks to this stage, mechanical damage to pipes can be identified and eliminated.

Pouring concrete mortar

All floor pouring 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. It is recommended to use tiles or linoleum as flooring. If you choose parquet or any other natural surface, due to possible temperature changes, such a surface may become unusable.

Manifold cabinet and its installation

Before calculating the pipe flow required for installation on the 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 used water. This device also allows you to maintain the required temperature in the room. It is worth noting that you need 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 manifold cabinet too high, since ultimately the water circulation may occur unevenly. The optimal height for installing a cabinet is 20-30 cm above the bare floor.

Tips for those who decide to install heated floors themselves

There must be an air vent on top of the collector cabinet. Laying heated floors under furniture is strictly prohibited. Firstly, because this will lead to damage to the materials from which the furniture is made. Secondly, it may cause a fire. Materials that are flammable may easily catch fire if the room is exposed to heat. Thirdly, heat from the floor must constantly rise, furniture prevents this, thus the pipes heat up faster and can deteriorate.

It is necessary to select a collector depending on the size of the room. In the store, when purchasing, 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.

Main qualities of pipes:

• Wear resistance;
• Heat resistance.

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

Before calculating a heated floor, consult with those who have already done this. Calculation of the area and number of pipes is important stage preparation for floor installation. In order not to make a mistake, 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 20 cm from the walls 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, and also notice mechanical damage.

If you install a heated floor correctly, it will serve you for many years. If you have any questions, it is better to ask them to an expert on our website or contact specialists who will efficiently, quickly and reliably improve and prepare your room for installing heated floors.

By warm floor It’s pleasant to walk, there is no discomfort from the cold underfoot and stuffiness in the upper part of the room. A well-equipped system allows you to evenly heat all areas of the rooms, creating comfort and saving money on heating. Installing a heated floor is relatively simple, but the efficiency of the heating circuit depends entirely on the correctness of the calculations when preparing the project.

In order for the warm floor to create the desired climate and not cause inconvenience or utility accidents, the room in which this heating circuit will be installed must meet the following requirements:

• the height of the ceilings from the subfloor should be such that reducing it by 20 cm does not cause discomfort;
• the doorway must have a height of at least 2.1 m;
• the subfloor must be strong enough to withstand the cement screed that will cover the thermal circuit;
• if the subfloor is laid on the ground or there is an unheated room under the insulated room, it is necessary to lay an additional layer of insulation with a shielding coating;
• the surface on which it is planned to install the thermal circuit and all components of the heated floor “pie” must be smooth and clean.

If the above requirements are met, the “warm floor” system will be installed without problems. However, its effectiveness depends not only on the size of the room, but also on its other features, which the following recommendations will help you take into account:

• Walls are the main source of heat loss, therefore, before calculating and installing a heating system, it is necessary to at least approximately calculate the volume of heat used to heat the street. If the resulting figure turns out to be above 100 W per square meter, it is advisable to insulate the walls so as not to overpay for heating;
• The thermal circuit should not fall under the installation sites of massive furniture and heavy stationary equipment. Constant high pressure on the floor will damage the pipes or cables of the heating system and cause it to fail.
• For uniform heating of the room, it is necessary that such unheated zones occupy no more than 30% of the floor area. Therefore, before making calculations, make a drawing of the room to scale, and mark on this drawing the places that should be left unheated. Then the total working area is calculated - it should be 70% or more of the total.
• It is necessary to calculate the optimal shape, length and pitch of the thermal circuit and its power, and also make a drawing indicating the connection points to the heating system and the direction of coolant flow.

Methods for installing a "warm floor" system

For proper functioning For this heating system, a clear sequence of layers of the so-called “pie” of the heated floor is important.

The thermal circuit is laid on a previously heat- and waterproofed surface, and poured or backfilled on top cement screed, on top of which the finishing floor covering is laid. The above layers - the pie shell - are required in both cases. They protect the system from external influences and increase its efficiency.