Various schemes of underfloor heating - screeds, pipes, equipment, connections. Wiring diagrams of water heated floors in a private house

Underfloor heating is an excellent option for creating a comfortable temperature in the room. Cool tiles please only in summer, and even then not always, but in winter bare feet on a cold floor are completely unpleasant. Installation of a warm floor will create acceptable conditions for the operation of any decorative floor covering, no matter whether it is a laminate or ceramic finish.

To date, there are 2 large groups of underfloor heating - water and electric. The first option is very laborious in installation, but economical in operation. The second, on the contrary, can be installed even by a beginner, but electricity bills will increase significantly. In this article we will tell you how the installation of a water-heated floor is going on and what you need to pay attention to.

general information

Before talking about the technology of installing a warm water floor, let's deal with the very concept of such an installation.

So, a warm floor is one of the variations of space heating, the most important feature of which is a large heat-releasing surface with constant air convection. In other words, with the same power of radiators and underfloor heating, it will be warmer in the room where the last option is installed.

In order for the layout of the underfloor heating to be as clear as possible for perception, it is worth first recalling the traditional scheme of water heating. The main heat-transfer elements in such a circuit are radiators. The air masses, heated from the walls of the radiator sections, rushes up, as they cool down, they go down, and such circulation occurs constantly.

Typical pipe laying patterns

Of course, modern batteries heat the room well, but there are also a lot of cold areas. Basically, this is the space near the floor surface, which does not fully warm up.

Features of the floor system

The technology of installation of water heated floors is characterized by a slightly different picture. The heating piping element is located directly in the cavity of the floor covering, and if this system is correctly installed, the heat coming from the source will be distributed evenly over the entire area of ​​the room.

As a result, the heat flows of air masses begin their upward movement directly from the coating itself, providing more comfortable conditions for a person. In addition, the feet are in constant contact with the floor, and when this surface is warm, it is impossible to freeze even in light clothes.

A water heated floor, the installation of which, although difficult, is quite within the power of inexperienced craftsmen, is in most cases used as the main heating system for a house, apartment or a separate room. And if electric floors can only be laid in a separate area, then installing a water heating system is too difficult to occupy just a couple of square meters.

What you need to know before installation

If you plan to use hot water as a heat carrier, the meaning of such a system is quite simple. Instead of batteries connected to centralized heating, a flexible special pipeline is laid under the coating, through which hot water will circulate. Such an installation can operate from an autonomous gas boiler.

It is forbidden to connect water underfloor heating in apartment buildings to a centralized highway. As a result of the operation of the equipment, the pressure in the entire riser will drop and the temperature may not be enough to reach the upper floors.

It is allowed to connect to the central network only in private houses, but this option is not ideal either, since you will have to wait for the moment when heating is supplied. Moreover, due to regular breakdowns of communications, the risk of being left without heating is quite high. Accordingly, the most rational option for installing warm water floors is either a private house or individual heating in a high-rise building.

Why is thermal insulation needed?

According to the rules for the installation of warm water floors, a mandatory stage of work is the laying of insulation under the pipeline. Often hired craftsmen overlook this, which leads to significant heat losses.

So, why is this material needed at all:

1. To create a heat-reflecting screen that does not allow heat to penetrate to the lower floors. Due to this ability, all the heat coming from the pipe is reflected and moves up into the room, but not into the interfloor space and not into the neighboring apartment.
2. The substrate is necessary for uniform distribution of heat over the entire surface. In its absence, the heating of the floor will not be entirely, but in separate fragments where the pipe runs.
3. Modern insulating mats are equipped with clamps, thanks to which the pipes are easily fixed and do not move when they are poured with a concrete screed. Also, with the help of such clamps, it is easy to observe the specified pitch between the turns.

Coefficient of thermal conductivity

If you put carpet, linoleum and other materials that do not conduct heat on top of the internal heating system, then its effectiveness will be minimized. Therefore, it is worth considering the properties of the materials and laying those that will not interfere with the transfer of heat.

The coefficient of thermal conductivity is an indicator that demonstrates the ability to transfer heat. The higher it is, the better the material will pass the waves coming from the system. These include laminate, ceramic tiles, self-leveling floors, etc.

Installation subtleties

Installation of a warm water floor is carried out according to a long-established scheme, when the pipeline is located in a concrete screed. Why is that? Everything is quite simple. Firstly, the large loads that pass through the pipes need reliable fastening and protection, and secondly, air is an excellent heat insulator, and therefore, if the pipes are in contact with air masses, then there is no sense in such a heating system.

1. First you need to clean and bring the floor surface to one level. After that, you should check if there are height differences. If they do not exceed 10 mm in height, you can proceed with the installation of a warm water floor.

If the difference exceeds 10 mm, it is necessary to use a self-leveling mixture, which hardens literally within 3-5 hours. But the traditional sand-cement mixture will also be quite high quality. To check the straightness, a building level is used.

1. The next stage is the installation of a waterproofing film that allows you to protect the coolant from moisture. It is desirable that this be a foil coating. After that, along the perimeter of the wall ceilings, a damper tape is laid and fixed to the height of the warm floor.

1. Next, the insulation is laid, the thickness of which depends solely on your preferences. A layer of vapor barrier material is placed on top of the insulation.
2. Carrying out reinforcement. To do this, you need to buy a reinforcing mesh with cells of 18-20 cm, which will allow you to lay the pipeline without any problems. This step can be skipped if mats with retainers are used for insulation.
3. Pipeline laying. First of all, you need to connect the pipe to the outlet of the collector installation for supply. If the internal system is the only source of heating, then they are laid with a small step, the value of which does not exceed 20 cm. When this floor heating system is an additional source of comfort, then a more sweeping laying step is allowed - up to 35 cm. with special clips. The pipeline may expand slightly during heating, so it does not need to be rigidly fixed.

Each circuit is laid in a whole piece, without resorting to additional connections. Such connecting elements increase the risk of various leaks.

1. Checking systems for performance and reliability. A test run of a water heated floor is carried out with an increase in pressure to about 0.3 MPa per hour, the water temperature should remain unchanged.
2. After successfully passing the tests, in which no leaks and defects were found, you can start pouring the screed. Its maximum height should not exceed 70 mm, otherwise, the heat emanating from the tubes will not be enough to overcome the thickness of the concrete mix.

If you doubt that you can independently carry out the installation of a warm water floor, it is better to turn to professional craftsmen who will help you realize your plan.

Now you know what a water heated floor is, installation, video and photographic materials of which are presented in this publication.

VIDEO: How to assemble a water heated floor with your own hands

Underfloor heating is a heating system that uses hot water as a heat source for a room. The principle of operation of such a heating system is quite simple: special flexible pipes are installed on the floor surface, through which a hot coolant is distributed.

The source of heat for such a heating system is a central heating system or a gas boiler. You can do the installation of a water-heated floor with your own hands, but before that you will need to draw up a project correctly and decide on the connection method.

The water floor heating system installed in the apartment consists of:

• Water heating boiler;
• circulation pump;
• Ball valves installed at the inlet to the boiler;
• Pipes for distributing and laying the heating main;
• Collector;
• Control and adjustment systems;
• Fittings connecting the manifold to the pipeline.

The boiler, which you yourself need to connect to the plumbing heating system, can be:

• Electric;
• gas;
• solid fuel;
• On liquid fuel.

The circulation pump is included with most boiler models, but before installing it, you should make a calculation and find out if it has enough power for the underfloor heating system. The power of the heating circuit, (kW) and the temperature of the coolant are taken into account.

The collector distributes hot water along the heating circuit - with its help, the underfloor heating in the apartment is adjusted and adjusted. You can make and connect a collector using metal-plastic pipes with your own hands - this will save money on installing the system.

The cake of a water-heated floor laid in a screed is divided into three layers - these are:

• Shielding substrate;
• Heating circuit;
• Finish flooring.

A foil-coated film is used as a shielding substrate. The film protects the heating circuit from possible heat losses.

A pie of a water-heated floor without a screed consists of:

• primary sex;
• Thermal insulation layer, best of all - a special polystyrene plate;
• Aluminum plates for pipe laying;
• heating pipes;
• Substrates;
• Finishing coverage.

Comparing water and electric underfloor heating, it should be noted that:

• It is more difficult and expensive to design and install a water floor than an electric one, but its operation is much cheaper. Heating 10 sq. m., the water floor consumes only 1.5 kW of electricity per hour.
• The water floor heating system is characterized by the complexity of adjusting the temperature in the apartment. Adjusting the heating of electric floors is quite simple.
• Starting floor heating with a water system takes much less time than with an electric one.
• With a large area of ​​\u200b\u200bthe room, it is possible to make a water floor the main source of heating; with a small area of ​​\u200b\u200bthe room, it is recommended to use electric floor heating.

Underfloor heating project

Optimum floor heating temperature.

The project drawing up instruction requires the availability of initial data, which includes the level of heat loss of the entire building and each room separately. In addition, it is necessary to calculate in advance the temperature value that should be in each room.

The technology is focused on averaged data, so the water floor generates an average of 100 W / m2 of energy, which is equal to the average heat loss of an “average building”. When drawing up a project, it must be taken into account that a warm water floor in each room will cover various heat losses. So, for example, in the bedroom they are 50 W / m2, in the hall 100 W / m2, in the bathroom 75 W / m2.

Pipe laying scheme

Pipes for the heat transfer system are made of cross-linked polyethylene, polypropylene, copper, metal-plastic or stainless steel. The advantage of polypropylene pipes is their low cost. Metal-plastic products retain shape stability and do not deform. Copper pipes have a long service life and a high degree of thermal conductivity. Pipes made of cross-linked polyethylene are characterized by high thermal stability and strength.

Before you start laying the floor water heating system with your own hands, you must select the pipeline pitch. Here, the step is the distance between the laid pipes that perform floor heating. The pipe laying step affects how evenly the temperature will be distributed over the floor surface.

The laying instruction allows you to use a step from 5 to 60 cm, but most often the pipes are laid in increments of 15-30 cm. The choice of this parameter must be made depending on the type and characteristics of the room, as well as indicators of its calculated heat load. For example, it is recommended to install a pipe system with a laying step of 15 cm in bathrooms and all those rooms where it is important to evenly distribute heat over the floor surface at a heating load level of more than 85 W / m2. You can lay the pipes yourself with an orientation to the following schemes:

When implementing the “snail” laying scheme, the pipeline must be laid in a spiral, which unwinds from the center of the room to the walls. "Snail" is the most popular and common method of laying pipes with your own hands. The design of such a scheme makes it possible for the supply and return to be located nearby, which helps to equalize the average floor temperature, in which cold zones will not occur.

Such a scheme allows heating to be carried out in the coldest areas located along the outer walls. Reverse loop instructions allow mounting closer to the center of the room. It is possible to do laying with a snake in rooms with a floor slope - it is important to correctly lay the heating circuit in the highest part of the room. This will contribute to the independent exit of air from the pipeline to the collector.

The layout of pipes with a double snake allows you to smooth out uneven floor heating. To perform this installation, you need to make double loops of the supply and return circuits. The laying technology allows the combination of “snail” and “snake” schemes - snake pipes are laid along the perimeter of the walls, and in the middle of the room they are laid in a spiral.

All presented methods directly depend on the characteristics of the room and the angle of the floor.

Advice! In the coldest areas, it is necessary to increase the density of the serpentine laying step to 10 cm, especially for areas near external walls.

Ways to connect the underfloor heating system

Do-it-yourself connection of the water floor follows the “pipe-collector-boiler” connection chain. The most common options are:

• Collector systems.
• Connection using three-way mixers;
• Connection with a circulation pump.

When connected using a collector, the system is mounted in such a way that return and supply pipes are freely connected to the collector cabinet. Further, tank collector outlets are connected to the pipes, providing the supply and return flow of the coolant. The design is equipped with shut-off valves, with thermometers installed in them to monitor the temperature regime.

Fixing pipes, valves and other elements is carried out using compressor fittings. In addition, the collectors can be fastened to the water floor contour using special connections - a brass nut, a clamping ring or a support sleeve. At the last stage, the collector is connected to the heat transfer pipes.

If you install and connect a system with a three-way mixer, then it should be installed at the outlet of the return circuit. You can mount such a system with your own hands by directly connecting a three-way mixer using pipes to the boiler.

The collector must be supplemented with a splitter, on the upper side of which an air vent is installed. This element will ensure the removal of air bubbles from a closed system. Fastening of all chain components can be done with fittings or clamping rings.

If the system has a low water pressure, and the mixer is not needed, then you can install a circulation pump equipped with a thermostat. The pump can be connected to the central heating system, but this must be done after agreement with the permitting authorities of the Housing Office. It is advisable to install the pump on the return circuit of the system, since when installed on the supply circuit, it will take excess water, which can harm the central heating system.

How to install a warm water floor with a screed

The underfloor heating system is installed in the following order:

1. The base is being prepared - the main requirement for the subfloor is a flat surface and dryness.
2. A waterproofing layer is being laid. As a waterproofing, ordinary polyethylene film can be used. The film is spread over the entire surface and glued with adhesive tape at the joints.
3. The damper tape is laid. You need to do this around the entire perimeter of the room.
4. The thermal insulation layer is installed. Expanded polystyrene foam can be used, on top of which a foil-coated film is laid.
5. In accordance with the markup, pipes are laid.

After hydraulic tests are carried out, it is the turn of concrete pouring. In order to make reinforcement, a metal mesh with a wire cross section of 5 mm, with a mesh size of 10x10 or 15x15 cm, should be used. The finishing screed can be poured from mixtures for self-leveling floors, special building mixtures or mortar with the addition of a plasticizer. The thickness of the concrete layer in this case should not be more than 30-35 mm.

Advice! An aluminum bar with a length of up to 2 m is best suited for leveling an uncured screed. The bar will help you quickly and efficiently complete the initial leveling.

After completion of the work, you need to wait for the complete solidification of the fill, and then lay the decorative coating.

How to install without a screed

A warm water-type floor can be installed without the use of a concrete screed - under a polystyrene base or wooden flooring.

Laying under a polystyrene base is carried out in the following order:

1. In accordance with the preliminary marking, the polystyrene foam base is laid in the form of plates. They are fastened to each other with special snap locks.
2. Aluminum plates are laid in the grooves, on top of which pipes are laid with an orientation to the laying plan of the heating circuit.
3. A waterproofing layer can be laid on top of the plates - an ordinary plastic film will do.
4. The top coat is laid on top of the plates.

When using wooden modules, the following actions are performed:

1. The modules are placed on the logs, while maintaining a step of 600 mm.
2. A waterproofing and insulating layer is laid between the lags.
3. The modules are interlocked with each other with special locks.
4. Metal plates are placed on top of the layer of prepared modules.
5. On top of the metal plates, pipes are laid according to the selected scheme.
6. If tiles or linoleum will be laid under a warm wooden floor, you will need to prepare a flat surface - put drywall sheets or chipboard plates on top of the metal plates, fix them and seal all joints and cracks with putty.

Water heated floors are a popular heating system with its unique properties. In order for these properties to manifest themselves in full glory, you need to take care of the correct laying of the entire warm floor cake. If you violate the technology, there is a risk of burying the system in the screed. And such cases are quite frequent. If you do not want this, then welcome to our material!

Due to the fact that the pipes of the warm floor are laid out over the entire area of ​​\u200b\u200bthe room, the most uniform heating of each area is achieved. Wherever you are in your home, you will be equally comfortable.

With water floors, in most cases, you get rid of radiators that used to take up extra space in your home. For all these features, they love water heated floors in private homes. Let's take a look at it step by step on our own.

Step 1. Prepare the base

The base for the warm floor in the house is a rough screed, which in most cases is not poured very carefully. Therefore, before you start laying the floors, clean the surface of the screed from excess debris. If there are influxes, bring them down to an even state. If there are recesses, trim them. These factors will further favorably affect the integrity of the system itself.

Step 2 Install the Distribution Manifold

Today, underfloor heating has become so popular and affordable that it is used in the arrangement of many modern homes. This method of space heating, unlike traditional central heating, has a huge number of advantages. At the same time, it is worth mentioning right away that laying a warm water floor in an apartment is highly not recommended, since various illegal connections to central heating batteries are completely prohibited. Other options are described in the article - “Laying a warm floor. Options."

Laying warm water floors - advantages and disadvantages of the system

Advantages

• Thanks to the use of warm water floors, it becomes possible to heat large areas with very significant savings in heat energy.
• They provide uniform heating of the room, without cold or overheated areas.
• They allow you to get the temperature regime that is as comfortable as possible for a person to live.
• Do not require special maintenance during operation.
• Combats moisture while maintaining an optimal level of humidity in the room.
• Underfloor heating water, laying which takes a minimum of time, can last at least 50 years.
• Do not create electromagnetic fields.
• There is a limited load size per unit area. As a rule - less than infrared film or cable floor.
• If one section or section is damaged, as well as a series connection of the pipeline, disconnecting this part and further operation of the system is impossible. In such cases, costly repairs will be required.

disadvantages

• long and relatively complex installation;
• inconvenience associated with long and painstaking styling;
• the need to reinforce the pipe or screed;
• the need to use a waterproofing layer, that is, a film;

Floor laying technology

Methods for laying a water floor

Installation of a warm water floor can be carried out using several methods:

• With a polystyrene system,
• With a concrete system
• By means of modular or rack type of the corresponding wood system.

When laying tiles, the concrete option is considered the most optimal way to install a water-heated floor, while aluminum plates or polystyrene plates are recommended only in residential areas or in those where there are floor height restrictions.

Water floor laying scheme

The two most common laying patterns for a warm water floor are a spiral (snail) and a snake (zigzag). The main advantage of the "snake" is the quick time and ease of installation of the system, and the "spiral" allows you to provide the highest quality heating of the room. The latter version of the scheme is ideal in cases where intensive heating is required for heavily freezing zones (for example, located next to windows).

Installation steps

When using the concrete method of laying a warm water floor, it is first necessary to lay thermal insulation. After that, a damper tape is laid around the perimeter of the room and a plastic film is spread. Then laying of the reinforcing mesh is required, which is necessary for reliable fastening of the pipes and their further installation.

Pipes are attached to the reinforcing mesh with plastic clamps. Expansion joints must be additionally protected using corrugated pipe (which is required for reliable protection against damage and thermal insulation). To give additional strength, you can use an additional layer of reinforcing mesh located on top of the pipes.

The basic scheme for laying a warm water floor is laying in the form of a snake or a spiral, in which per 1 sq.m. about 5 meters of pipe will be required. If you need to heat a room with a large area, you need to use several loops.

After the installation of the underfloor heating is completed, it is imperative to carry out hydraulic tests. This is especially important in cases where the installation work is carried out on their own.

Thanks to a timely inspection, it is possible to identify in advance various damage to pipes or flaws in their installation, if any. Hydraulic tests are carried out, as a rule, within 24 hours (at least) at a pressure of 3-4 bar.

After that, the mounted floor surface must be poured with a concrete screed, thanks to which the heat will be evenly distributed over the entire area of ​​\u200b\u200bthe room. The screed should be located above the pipes no higher than 15 cm, but not lower than 3 cm.

It should be remembered that the warm water floor cannot be turned on until the solution is completely dry. The drying rate of the screed depends on its thickness.

The next step in laying a water-heated floor is that it is necessary to gradually increase its temperature. As a rule, already on the third day, the warm floor acquires the most comfortable temperature regime for living.

The choice of flooring for laying on a warm floor

The laying scheme of a warm water floor implies the use of a finishing floor covering at the end of the installation work, the quality and texture of which largely determine the comfort of staying in the room. One of the most suitable coatings in such cases is ceramic tiles, which have high abrasion resistance, good thermal conductivity, as well as resistance to deformation resulting from sudden temperature changes.

Laying a water heated floor, a video about which contains more detailed information about the main stages of work, allows you to use not only ceramic tiles, but also other coatings as a floor covering. In this case, it is best to give preference to laminate, which is much more convenient to use than other materials. The only thing to take into account when choosing this material is that special brands of laminate should be used for underfloor heating, which have good resistance to temperature changes.

Now many residents of private houses install a water-heated floor for basic or additional heating. It has a lot of advantages: it increases comfort, heats the room evenly, does not require additional energy costs (because it works from one boiler with radiators). The instructions in our article will allow you to install water-heated floors, even without experience. However, before that, it is worth studying all the nuances.

Best of all, the warm water floor system is combined with laying under and tile.

• First, both materials are strong and durable.
• Secondly, they do not emit harmful substances when heated.
• And thirdly, heating perfectly complements the tile (the material itself is cold), and you can even walk on it barefoot due to its high heat capacity.

Of course, underfloor heating can also be done under linoleum, PVC tiles and even carpet, with a special mark.

But, for example, it makes no sense to heat the carpet, and the surface temperature must not exceed 31 ° C, according to SNiP 41-01-2003. Otherwise, it will provoke the release of harmful substances.

Installation in an apartment

Probably, many residents had the idea to independently connect “for free” water heated floors to the central heating system or hot water supply. And some even do so, but in most cases it is prohibited by local law.

For example, in Moscow there is a government decree No. 73-PP dated February 8, 2005, in Appendix No. 2 it is clearly written about the ban on the conversion of public water supply systems for underfloor heating.

Violating the rules, at best, you can get a fine the first time you visit the plumbers. And at worst, the risk of leaving neighbors without heating.

In some regions, the ban does not apply, but an examination is required to connect in order not to disrupt the system.

In general, from a technical point of view, such options are possible, but only if a separate pumping and mixing unit is connected and the outlet pressure in the system is maintained.

Note! If there is a jet pump (elevator) in an apartment building, then metal-plastic and polypropylene pipes cannot be used.

Floor installation methods

There are several ways to arrange a warm water floor.

• The most popular and reliable of them is a concrete screed. Unlike electric types, 16 mm pipes cannot be hidden in tile adhesive, and it will not work. Therefore, a screed is poured at least 3 cm above the pipes.
• The second way is laying pipes in the cut out grooves of polystyrene foam. The grooves are made by hand, pipes are laid inside, then the screed is poured.
• The next option is often used in houses with wooden floors, although it requires a lot of labor - this is laying in wooden grooves. To do this, boards are stuffed on the floor, which create a gutter of the desired shape for laying.

Types of pipes used

Three types of pipes are suitable for a warm water floor.

• Pipes made of cross-linked polyethylene (PEX-EVOH-PEX) are inconvenient to use, because it is difficult to give them the desired shape (they straighten when heated). But they are not afraid of liquid freezing and are maintainable.
• Metal-plastic pipes - the best option: low price, ease of installation, stably keep their shape.
• Copper pipes are expensive; when used in a screed, they must be covered with a protective layer to prevent alkaline exposure.

Calculation of a warm water floor

Before installation and purchase of materials, it is imperative to calculate the underfloor heating. To do this, they draw a diagram with contours, which will then come in handy during repair work in order to know the position of the pipes.

• If you are sure that furniture or plumbing will always stand in a certain place, pipes are not laid in this place.
• The length of the circuit with a diameter of 16 mm must not exceed 100 m (maximum for 20 mm is 120 m), otherwise the pressure in the system will be bad. Thus, each circuit approximately occupies no more than 15 square meters. m.
• The difference between the length of several circuits should be small (less than 15 m), that is, they should all be of uniform length. Large rooms, respectively, are divided into several circuits.
• The optimum pipe spacing is 15 cm when using good thermal insulation. If in winter there are often frosts below -20, then the step is reduced to 10 cm (only possible at the outer walls). And in the north you can not do without additional radiators.
• With a laying step of 15 cm, the consumption of pipes is approximately 6.7 m for each square of the room, when laying every 10 cm - 10 m.

The graph shows the dependence of the flux density on the average coolant temperature. Dotted lines indicate pipes with a diameter of 20 mm, and solid lines - 16 mm.

The graph shows data that is valid only when using a cement-sand screed with a thickness of 7 cm, covered with tiles. If the thickness of the screed is increased, for example, by 1 cm, then the heat flux density decreases by 5-8%.

• To find the flux density, the sum of the heat loss of the room in watts is divided by the pipe laying area (the distance from the walls is subtracted).
• The average temperature is calculated as the average value at the inlet to the circuit and the outlet from the return.

The optimum temperature at the inlet and outlet should not differ by more than 5-10 degrees. The maximum temperature of the heat carrier must not exceed 55°C.

According to the above diagram, you can only perform a rough calculation and make the final adjustment due to the mixing unit and thermostats. For accurate design, be sure to contact professional heating engineers.

Heated floor cake

The technology of laying a warm water floor consists of several layers, which are laid in a certain sequence. The total thickness of the cake is 8-14 cm, the load on the floors is up to 300 kg / sq. m.

If the base is a concrete slab:

• waterproofing;
• insulation;
• reinforcing mesh;
• water floor heating pipe;
• coupler.

For waterproofing, it is permissible to use ordinary polyethylene film or special materials. The damper tape is made from cut strips of thermal insulation 1-2 cm thick, or they buy a ready-made version with a self-adhesive base.
The choice of insulation depends on several factors: region, base material. For example, for floors on the ground, extruded polystyrene foam with a thickness of at least 5 cm (optimally 10) is also used, and if there is a warm basement under the floor of the first floor, then thinner options from 3 cm can be used.

The main purpose of the insulation is to direct the heat from the heating up and prevent large heat losses.

If the base is floors on the ground:

• bulk soil 15 cm;
• crushed stone 10 cm;
• sand 5 cm;
• rough screed;
• waterproofing;
• damper tape around the perimeter;
• extruded polystyrene foam not less than 5 cm;
• reinforced screed with heat carriers.

It is important to carefully compact the preparatory layers for the rough screed in layers. With a dense compaction of the base and the use of extruded polystyrene foam, it will not be necessary to make a rough screed.

Installation of a warm floor

Let's say a good foundation has already been prepared: a flat concrete slab or a backfill layer without strong drops. The differences should not exceed 7 mm when checking with a two-meter rail. If there are irregularities, they can be covered with sand.

Waterproofing

Someone lays waterproofing under the bottom of the insulation, someone, on the contrary, upstairs, and some use it both here and there.
If extruded polystyrene foam is used, it practically does not need waterproofing, so its position is not so critical. But it will not allow cement milk to penetrate between the seams of the insulation and go into the slab and will additionally retain moisture from below.
If you fix it to the bottom of the insulation, then you can fix the pipes on the warm floor directly to the insulation. If the waterproofing is laid up, then laying the mounting grid will be required to fix the pipes.

We lay waterproofing with an overlap on the walls by 20 cm, and on top of each other. We glue the joints with adhesive tape for sealing.

damper tape

If you bought a finished tape, just glue it around the perimeter. It usually has a thickness of 5-8 mm and a height of 10-15 cm. The height should be above the fill level, the excess is cut off with a knife. If the tape is made by hand, then be sure to glue or screw it with self-tapping screws to the wall.

The linear expansion of concrete is 0.5 mm per meter when heated to 40°C.

insulation

Sheet insulation for a warm water floor is laid with offset joints so that it is tightly connected.

Reinforcement

The first layer of reinforcing mesh is usually laid on the insulation and used as a base for fixing the contours and evenly distributing heat over the surface. The grids are tied together with wire. Pipes are attached to the grid on nylon clamps.

The diameter of the mesh bars is 4-5 mm, and the cell size is depending on the pipe laying step, for easy fastening.

In addition, it is imperative to lay reinforcement on top of the pipes, because even when using mesh from below, it will have almost no effect if it lies at the very bottom. Or, during pouring, put the grid on stands, creating a gap.

Pipe Fixation Methods

Water heated floor can be laid in several ways, we list them.

• Clamp made of polyamide. Used for quick fastening of pipes to the mounting grid. Consumption - about 2 pieces per 1 m.
• Mounting wire made of steel. Also used for mounting to the grid, the flow rate is exactly the same.
• Stapler and clamps. Suitable for quick fixing of pipes to thermal insulation. The consumption of clamps is 2 pieces per 1 m.
• Fixing track. It is a U-shaped PVC strip, which serves as a base for laying 16 or 20 mm pipes into it. Attaches firmly to the floor.
• Mats for a warm water floor made of polystyrene. A pipe is laid in the middle of the grooves between the posts.
• Distribution aluminum plate. Used when installing in wooden floors, reflects and evenly distributes heat over the surface.

Pipe laying

The pipes are laid with an indent from the walls of 15-20 cm. It is highly desirable to make each circuit from a single pipe without welding, and their length should not exceed 100 m. The step between the pipes at the walls is 10 cm, closer to the center - 15 cm.

The scheme of laying a warm floor is different, for example, a spiral or a snake. At the outer walls, they try to make the laying step more often or draw a contour from the feed next to the cold walls. An example of a scheme for enhanced heating of external walls is shown in the photo, this option is best used in cold regions:



In other cases, the contours are usually laid in a spiral (snail), this is a universal option.

In places with a large accumulation of pipes, in order to avoid overheating of the surface, some of them are covered with a heat-insulating tube.

Metal-plastic 16 mm and 20 mm can be easily bent by hand, without the use of special tools. In order to evenly bend the pipes with an angle of small radius and at the same time prevent it from cracking, the corners are bent in several passes (arm interceptions).
Approximately 5-6 interceptions will be needed at an angle of 90 °. This means, at first, resting with your thumbs, make a slight bend, then slightly shift your hands in the direction of the bend and repeat the actions.

The presence of kinks on the pipes in places of sharp turns is unacceptable.

Polypropylene pipes are much more difficult to bend because they are springy. Therefore, they are heated or made to bend, but in the case of a warm floor, they are simply attached to the grid, making the bends less sharp.

We begin the installation of a water-heated floor by connecting the first end of the pipe to the distribution manifold, and after laying the room, the return line (the second end) is immediately connected.

Connecting circuits

In most cases, the circuits are connected through a distribution node. It has several functions: increasing the pressure in the system, adjusting the temperature, uniform supply to several circuits, combining with radiators.

There are many connection schemes to the boiler, which we wrote about in the article about: with manual adjustment, with weather automatics and auto-adjustment using servos and sensors.

Pipes are connected to the manifold using Eurocone clamp fittings.

Crimping

When you have completed the installation of all circuits, be sure to conduct a pneumatic test of the system for tightness. To do this, pressure is applied using a compressor. For testing, a small household compressor with a pressure of more than 6 bar is suitable. The pressure in the system is brought to 4 bar and left for the entire time until the system is started.

Since air molecules are much smaller than water molecules, even a small depressurization can be detected. In addition, the water can freeze if you do not have time to turn on the heating, and nothing will happen to the air.

Underfloor heating screed

Filling the screed is done only after the installation of all circuits and hydraulic tests. It is recommended to use concrete not lower than M-300 (B-22.5) with crushed stone with a fraction of 5-20 mm. A minimum thickness of 3 cm above the pipe is made not only to obtain the desired strength, but also to evenly distribute heat over the surface. Weight 1 sq. m. screed with a thickness of 5 cm is up to 125 kg.

With a screed thickness of more than 15 cm or with high loads, an additional calculation of the thermal regime is required.

With an increase in the thickness of the screed, it takes more time to heat it up to a certain temperature after switching on, and the inertia of the system also increases. The lower the thermal conductivity of the screed, the higher the temperature of the coolant will need to be made.

expansion joints

The absence or incorrect position of thermal gaps is the most common cause of screed failure.

Shrink joints are made in the following cases:

• The premises are over 30 sq. m.;
• walls have a length of more than 8 m;
• the length and width of the room differ by more than 2 times;
• over expansion joints of structures;
• the room is too curved.

To do this, a damper tape is laid around the perimeter of the seams. At the seam, the reinforcing mesh must be divided. The expansion gap must be 10 mm thick at the base. The upper part is treated with a sealant. If the room has a non-standard shape, it must be divided into simpler rectangular or square elements.




If the pipes pass through expansion joints in the screed, in these places they are laid in a corrugated pipe, 30 cm of corrugations in each direction (according to SP 41-102-98 - 50 cm on each side). It is recommended not to separate one circuit with expansion joints; supply and return pipes must pass through it.

When laying tiles on expansion joints, the likelihood of its peeling off increases due to different expansion of adjacent tiles. To avoid this, the first part is laid on tile adhesive, and the second part is attached to an elastic sealant.

Partial profile expansion joints can be used for additional separation. They are made with a trowel, 1/3 of the thickness. After the concrete has hardened, they are also sealed with sealant. If pipes pass through them, they are also protected by corrugation.

Cracks in the screed

A fairly common occurrence is the appearance of cracks on the screed after drying. This can be caused by a number of reasons:

• low density insulation;
• poor compaction of the solution;
• lack of plasticizers;
• too thick screed;
• lack of shrinkage seams;
• too fast drying of concrete;
• incorrect proportions of the solution.

It's very easy to avoid them:

• insulation must be used with a density above 35-40 kg / m3;
• the screed solution must be plastic when laying and with the addition of fiber and plasticizer;
• in large rooms, shrink joints should be made (see below);
• also, concrete should not be allowed to set quickly, for this it is covered with plastic wrap the next day (for a week).

Screed mortar

For a warm floor, it is imperative to use a plasticizer to increase the elasticity and strength of concrete. But you need to use special types of non-air-entraining plasticizers for underfloor heating.

Without experience, it will not work to make a cement-sand screed for a warm floor without crushed stone / gravel, and the correct branded DSP will cost more than factory concrete. Therefore, in order to avoid cracks due to a violation of the composition of the mortar, concrete with crushed stone is poured.

A solution of M-300 from cement grade M-400, washed sand and gravel is made in the following proportions.

• Mass composition C: P: W (kg) = 1: 1.9: 3.7.
• Volumetric composition per 10 liters of cement P: W (l) = 17:32.
• From 10 liters of cement, 41 liters of mortar will be obtained.
• The volumetric weight of such concrete M300 will be 2300-2500 kg / m3 (heavy concrete)

There is also another option using granite screenings instead of sand, the following elements were used for its preparation:

• 2 buckets of crushed stone with a fraction of 5-20 mm;
• water 7-8 liters;
• superplasticizer SP1 400 ml of solution (1.8 liters of powder is diluted in 5 liters of hot water);
• 1 bucket of cement;
• 3-4 buckets of granite screenings with a fraction of 0-5 mm;
• bucket volume - 12 liters.

High-quality concrete should not release water during laying (delaminate). If everything is done correctly and the air temperature is 20 ° C, it should begin to set after 4 hours, and after 12 hours it will not leave marks from the heels.

After 3 days after pouring, the screed will gain half its strength, and will completely harden only after 28 days. It is not recommended to turn on the heating system until this moment.

Mounting on a wooden floor

Wood does not conduct heat as efficiently as concrete, but mounting on it is also feasible. For this, aluminum distribution plates are used. The pipes are laid in wooden grooves made by attaching pre-prepared boards.

For the installation of linoleum, carpet and other materials that require a flat surface, a leveling layer of chipboard, plywood or GVL is laid over the pipes. If parquet or laminate is used as a topcoat, the design of the warm floor can be slightly simplified without the use of a leveling layer.

When choosing plywood and chipboard, make sure that they have hygienic and thermomechanical parameters that allow them to be used with underfloor heating.

Prices for underfloor heating

The price of a warm water floor is formed from several components:

• cost of materials (pipes, insulation, fasteners, etc.);
• the cost of the pumping and mixing unit and the collector;
• work on leveling the base and pouring the top layer of the screed;
• the cost of installing underfloor heating.

On average, the price of a water-heated floor during turnkey installation, together with all materials and work, will cost about 1,500-3,000 rubles per 1 sq. m.

Below is an approximate estimate for a house of 100 sq. m., but the prices for water-heated floors are highly dependent on the region, so it is best to drive in your data there and make an independent calculation. It does not take into account the costs of installation and purchase of radiators, a boiler, topcoat and screed.

Installation of warm water floors is shown in the video: