Water-heated gas floor. Classic water heated floor: device and principle of operation. Boiler selection criteria

Having chosen the option of water heated floors, also called hydraulic, for heating, you will have to put a lot of effort into installing them. Of all the possible types of underfloor heating, water is the most difficult to install, however, the result is a durable one that allows you to achieve greater comfort and savings than a traditional radiator system. You can reduce the cost of installation somewhat if you install a water-heated floor yourself. To do this, it is necessary to purchase all the necessary elements and materials, as well as prepare the floor surface in all rooms involved in accordance with established requirements.

If you have not yet fully decided on the type of heated floor -.

Surface preparation. Features of insulation of the base under a warm floor

The old screed is completely dismantled down to the base. In contrast, when installing a heated floor, you should already level the floor horizontally at the initial stage if there are differences of more than 10 mm.

Important: When using a water heated floor, the device of which has several circuits, the damper tape is also laid along the line between the circuits.

To prevent heat from escaping downwards, it is necessary to insulate the base of the floor. Depending on the location of the room and the type of floor, as well as the target orientation of the heating system, the appropriate insulation is selected:

• If the heated floor is an addition to the main heating system, then it is enough to use foamed polyethylene with a reflective foil coating as a substrate for the heated floor (penofol).
• For apartments with heated rooms on the floor below, it is enough to use sheets of expanded polystyrene or extruded polystyrene foam with a thickness of 20 to 50 mm or other durable insulation of suitable thickness.
• For first-floor apartments with an unheated basement or houses in which the floor is located on the ground, more serious insulation should be used in the form of expanded clay and expanded polystyrene sheets 50-100 mm thick.

Advice: You can use specialized insulation for heated floors. On the one hand, such materials are already equipped with special channels for laying pipes of underfloor heating systems.

A reinforcing mesh is laid on top of the insulation. It is necessary to secure the screed layer that will cover the entire underfloor heating system. Among other things, it is possible to subsequently attach the heated floor pipe to the mesh, instead of using special fastening strips and clips. In this case, ordinary plastic ties are used.

Diagram of the heated floor surface

Selection of materials and necessary devices

Before making a heated floor with your own hands, you should decide on the composition of the equipment and all elements of the system and calculate the materials.

The composition and design of a warm water floor includes the following elements:

1. Water heating boiler;
2. Pressure pump (may be included in the boiler);
3. Ball valves at the boiler inlet;
4. Distribution pipes;
5. A manifold with a system for setting and adjusting heated floors;
6. Pipes for laying on the floor surface;
7. Various fittings for laying the main route from the boiler and connecting underfloor heating pipes to the collector.

The pipe material for water heated floors can be either polypropylene or cross-linked polyethylene. It is better to choose polypropylene pipes with glass fiber reinforcement, since polypropylene itself has a significant linear expansion when heated. Polyethylene pipes are less susceptible to expansion. It is the latter that are most widespread in the layout of surface heating systems.

Pipes with a diameter of 16-20 mm are used. It is necessary that the pipe can withstand temperatures up to 95 degrees and a pressure of 10 Bar. It is not necessary to chase expensive options with oxygen protection and additional layers. Especially if the main goal is to reduce the overall costs of installing heated floors.

The collector is a pipe with a number of branches (splitter). It is necessary to connect several underfloor heating circuits to one main warm water supply line and return, cooled water intake. In this case, two splitters are used, which are installed in a special manifold cabinet. One for distribution hot water, and the second - for collecting return, cooled water. It is within the manifold that all the necessary elements for setting up heated floors are located: valves, flow regulators, air vents and emergency drain systems.

Diagram example of connecting a water heated floor

Calculation and distribution of pipes

For each room, the calculation of the length of the pipe and the pitch of its installation must be made separately. Calculations of water heated floors can be performed using specialized programs or using the services of design organizations. It is very difficult to independently calculate the required power for each circuit; a lot of parameters and nuances are taken into account. If you make a mistake in the calculations, this can negate the entire operation of the system or lead to unpleasant consequences, including: insufficient water circulation, the appearance of a “thermal zebra” when warm and cold areas alternate across the floor, uneven heating of the floor and the formation of leakage points heat.

To carry out calculations, the following parameters are required:

1. Room dimensions;
2. Material of walls, ceilings and thermal insulation;
3. Type of thermal insulation for underfloor heating;
4. Type flooring;
5. Diameter of pipes in the underfloor heating system and material;
6. Boiler power (water temperature).

Using these data, you can determine the required length of the pipe used for the room and the pitch of its installation to achieve the required heat transfer power.

When distributing pipes, you should choose the optimal laying route. It is important to consider that water gradually cools as it passes through the pipes. By the way, this is not a disadvantage, but rather a plus of water heated floors, because heat loss in the room does not occur evenly.

When distributing water heated floor pipes in each circuit, a number of rules should be followed:

• It is advisable to start laying pipes from the outer, colder walls of the room;

Important: If the pipe entry into the room is not from the side external wall, then the section of the pipe from the entrance to the wall is insulated.

• To gradually reduce the heating of the floor from the outer wall to the inner one, the “snake” laying method is used;
• For uniform floor heating in rooms with all internal walls(in the bathroom, wardrobe, etc.) laying is used in a spiral from the edge of the room to the center. The pipe is brought in a spiral to the center with a double pitch between the turns, after which it turns around and unwinds in the opposite direction until it leaves the room and goes to the collector.

In addition to the length and shape of the pipe distribution, you should calculate them hydraulic resistance. It increases with increasing length and every turn. In all circuits connected to the same collector, it is advisable to bring the resistance to same value. To resolve such situations, it is necessary to divide large circuits with a pipe length of more than a hundred meters into several smaller ones.

For each circuit, a single piece of pipe of the required length is purchased. It is unacceptable to use joints and couplings on pipes that are laid in a screed. So the length calculation and order should be carried out after carefully carried out calculations with thinking through the entire laying route.

Important: The calculation is carried out for each room separately. It is also undesirable to use one circuit to heat several rooms.

To insulate a loggia, veranda, or attic, a separate circuit is laid, not combined with adjacent rooms. Otherwise, most of the heat will go to heating it, and the room will remain cold. Insulation under a heated floor is carried out in the same way as with a floor located on the ground. Otherwise, there are no differences in terms of installing heated floors on the loggia.

Video: theoretical seminar on the installation of heated floors

Collector selection and installation

typical manifold for underfloor heating

Having decided on the number of circuits, you can select the appropriate collector. It must have enough leads to connect all the circuits. In addition, the collector is responsible for regulating and adjusting water heated floors. In the simplest version, the manifold is equipped only with shut-off valves, which significantly reduces the cost of the system, but practically makes it impossible to customize its operation.

Options that require the installation of control valves are slightly more expensive. With their help, you can adjust the water flow for each loop separately. Although the increase in cost will be noticeable, such a system will allow you to set up a warm floor for uniform heating of all rooms.

Mandatory elements for the manifold are an air vent valve and a drain outlet.

To fully automate a hydraulic heated floor, manifolds with servo drives on valves and special pre-mixers are used, which regulate the temperature of the supplied water, mixing it with the cooled return water. Such systems, at their cost, can make up a large part of the budget for the entire installation of heated floors. For private use there is no particular need for them, because it is easier to carefully configure the collector group more than once simple type than to spend money on an automatic system, which will operate in the same mode even under constant loads.

An example of connecting a heated floor collector

The underfloor heating manifold is installed in a special manifold box. The thickness of such a box is most often 12 cm. The dimensions are selected taking into account the dimensions of the manifold group with all the necessary additions in the form of pressure sensors, air vents and drains. Under the collector group there should be space to the floor necessary for bending the pipes supplied from all the contours of the heated floor.

The actual installation of a water heated floor begins with the placement of a manifold cabinet. The manifold cabinet should be placed so that the pipes from each room and circuit are approximately equal in length. In some situations, you can move the cabinet closer to the largest contours.

The easiest way to hide a cabinet is to mount it into the wall. The thickness of 12 cm is quite sufficient. The main thing to remember is that punching holes and recesses in load-bearing walls is strongly discouraged and even prohibited in most cases.

Important: The box should be installed above the level of heated floors, preventing pipes from diverting upward from it. Only in this case can the air exhaust system work adequately.

The manifold cabinet is assembled and filled according to general standard in accordance with the instructions of the manifold used, so there will be no problems with installing all elements and additional equipment.

Video: manifold assembly

Selecting a heating boiler

The choice of boiler is primarily determined by its power. It must cope with heating water at peak times of system load and have some power reserve. Roughly, this means that the boiler power should be equal to the total power of all heated floors plus a margin of 15-20%.

A pump is required to circulate water in the system. Modern boilers, both electric and gas, have a built-in pump. In most cases, it is enough to heat one- and two-story residential buildings. Only if the square footage of the heated room exceeds 120-150 m² may it be necessary to install additional auxiliary pumps. In this case, they are installed in remote collector cabinets.

Shut-off valves are installed directly at the boiler inlet and outlet. This will help turn off the boiler in case of repair or maintenance without having to drain all the water from the system.

Important: If there are several manifold cabinets, then a splitter is installed on the main route for supplying warm water, and after it - narrowing adapters. This is necessary for uniform distribution of water throughout the system.

general view of the entire system (connection of radiators can be excluded)

Installation of water heated floor pipes and pouring screed

Basically, heated floors are laid using special fastening profiles, which are secured to the floor with dowels and screws. They have sockets for securing pipes. With their help, it is much easier to maintain the pitch distance between the turns of the pipe.

Advice: To secure it, it is enough to use plastic ties that press the pipe to the reinforcing mesh. It is important not to tighten the pipe too tightly; it is better to keep the tie loop free.

Pipes are most often supplied in the form of coils. Do not pull the pipe out of the coil, turn by turn. It is necessary to unwind it gradually as it is laid and secured to the floor. All bends are made carefully in compliance with the minimum possible radius limit. Most often, for polyethylene pipes this radius is equal to 5 diameters.

If you compress a polyethylene pipe too much, a whitish stripe may appear on the bend. This means that the material began to sharply stretch and a crease formed. Unfortunately, such defects cannot be installed in a heated floor system due to the increasing risk of a breakthrough in this place.

The ends of the pipes that are supplied to the collector are, if necessary, laid through the walls and enclosed in insulation made of foamed polyethylene. To connect the pipes to the manifold, either a Eurocone system or a compression fitting is used.

If this is your first time encountering polypropylene pipes – .

There are several schemes for laying underfloor heating pipes. You can choose the right one based on your needs. Along with other factors, it is worth paying attention to the arrangement of furniture and plans for rearranging it.

When the installation of underfloor heating is completed, a mandatory high-pressure system check is performed. To do this, water is poured into the pipes and a pressure of 5-6 bar is applied for 24 hours. If no leaks or significant expansions are noticed on the pipes, then you can begin pouring the concrete screed. Filling is carried out at connected operating pressure in the pipes. Only after 28 days can we consider that the screed is ready and begin further work for installation of flooring.

Important nuances of forming a heated floor screed

There are some peculiarities in the formation of screeds over water-heated floors. This is due to the principle of heat distribution in its thickness and the floor covering used.

• If the heated floor is laid under the tiles, then you should make a screed about 3-5 cm thick, or distribute the pipes at intervals of 10-15 cm. Otherwise, the heat from the pipes will not properly warm the space between them, and this phenomenon will appear like a "thermal zebra". In this case, the alternation of warm and cold stripes will be quite clearly felt by the foot.
• Under laminate, linoleum, etc. It is advisable to form a thinner screed. For strength, in this case, another reinforcing mesh is used on top of the heated floor. This will reduce the heat path from the pipes to the flooring surface. Also, a layer of thermal insulation is not placed under the laminate, because it will only worsen the efficiency of the heated floor.

You can turn on the water heated floor heating at the first hint of the onset of autumn cold. The initial warm-up may take several days, after which the system will already maintain the required temperature. The greater inertia of water heated floors can also play a good role, even if for some reason the boiler is not able to heat the water for some time, the system will continue to transfer heat to the premises for a long time. In addition, you can keep the underfloor heating system on low power throughout the year, turning off most of the circuits and leaving only the part that heats the rooms where the flooring is made of ceramic tiles or self-leveling floors(hallway, bathroom, etc.), because even in hot weather such coatings feel cold.

Video: Installation of a water heated floor with your own hands

A few words about connecting the heating system to a wall-mounted gas boiler. The manufacturer does not matter; all boilers are connected and operate on a similar principle. It also doesn't matter if you do connecting a heated floor to the boiler or you have a radiator heating system - the boiler piping is the same. But since we are on the topic of warm floors, we will talk about connecting a warm water floor to the boiler.

Clarification. To connect a heated floor to a boiler, you will most likely need one of the diagrams from the design section.

Connecting a heated floor to a wall-mounted boiler (simple diagram)

This is a warm floor without a mixing unit.

We have a wall-mounted boiler, gas or electric, and we need to connect a heated floor, installed only on one floor, and there is one collector.

The easiest option is to connect the collector directly to the boiler:

Many people do this, because the boiler itself also has a temperature regulator. The boiler is set to the required temperature and that’s it, no problems. The boiler pump will “push” the heated floor up to 150 m2. Just remember during installation about the need for valves on the supply pipe and on the return pipe in front of the boiler and in front of the manifold. Well, it’s better to make the line from the boiler to the collector from the 32nd pipe.

Connecting heated floors and other equipment to the boiler

It is possible that the heating conditions in your home will change over time: after a while you decide to add radiators or a boiler to the warm floor indirect heating, or build/attach something else and there will be radiators... I think the idea is clear. And your heated floor is connected to the boiler according to the simple (first) diagram given above.

It's okay, you don't have to redo the entire system. It will be enough to install a mixing unit directly in front of the collector, add a hydraulic arrow between the boiler and the collector, and connect other heating equipment through it.

Technology for connecting a heated floor to a boiler

The boiler has five outputs (if the boiler is double-circuit, that is, for the heating and hot water supply system):

Outputs from left to right: 1 – hot water outlet from the boiler to the heating system (supply); 2 – exit from the boiler to the hot water supply system; 3 – gas supply; 4 – cold water inlet; 5 – return from the heating system.

At connecting the heated floor to the boiler Please note the following (see photo). All pipeline connections to the boiler are detachable: using union nuts and combination couplings. A ball valve is installed on each pipe.

A corrugated stainless pipe is used for gas supply.

Each boiler has a make-up tap (the blue lever of this tap is visible below) to feed/fill the heating system from the water supply system:

Replenishment is made by opening this tap, and then using the pressure gauge on the boiler panel we monitor the pressure in the system (1-1.5 atm.):

The following photo shows a safety unit consisting of an automatic air vent, valve and pressure gauge:

This block is installed for a floor-standing boiler (since we remember that wall-mounted boilers already have all this built-in).

Next in the photo is the connection of pipelines to a floor-standing boiler (this has already been discussed in the relevant articles on radiator heating, so here I do not go into detail about what is what in the image, yes, I think that everyone who tinkered with plumbing, pipes, etc. . personal belongings, without my chewing, he will understand everything; nevertheless, I give a link to the section where you can, in as many as three articles):

Return circulation pump:

And between the pump and the boiler there is a ball valve and the expansion tank (red) is visible:

Ball valve for feeding the system.

A gas heating boiler is a device that uses fuel combustion (natural or liquefied gas) to heat the coolant.

Design (design) of a gas boiler: burner, heat exchanger, thermally insulated housing, hydraulic unit, as well as safety and control devices. Such gas boilers require a chimney connection to remove combustion products. The chimney can be either ordinary vertical or coaxial (“pipe in pipe”) for boilers with a closed combustion chamber. Many modern boilers are equipped with built-in pumps for forced water circulation.

The principle of operation of a gas boiler- the coolant, passing through the heat exchanger, heats up and then circulates through the heating system, releasing the resulting thermal energy through radiators, heated floors, heated towel rails, and also providing water heating in an indirect heating boiler (if it is connected to a gas boiler).

A heat exchanger is a metal container in which the coolant (water or antifreeze) is heated - can be made of steel, cast iron, copper, etc. The reliability and durability of a gas boiler depend primarily on the quality of the heat exchanger. Cast iron heat exchangers are corrosion resistant and have a long service life, but are sensitive to sudden change temperatures and differ in significant weight. Steel containers can suffer from rust, so their internal surfaces are protected with various anti-corrosion coatings to extend the “life” of the device. Steel heat exchangers are the most common in boiler production. Copper heat exchangers are not susceptible to corrosion, and due to their high heat transfer coefficient, low weight and dimensions, such heat exchangers are often used in wall-mounted boilers, but one of the minuses should be noted that they are more expensive than steel ones.
In addition to the heat exchanger, an important part of gas boilers is the burner, which can be of various types: atmospheric or fan, single-stage or two-stage, with smooth modulation, double.

To control a gas boiler, automation is used with various settings and functions (for example, a weather-dependent control system), as well as devices for programming operation and remote control of the boiler.

Main technical characteristics gas heating boilers are: power, number of heating circuits, type of fuel., type of combustion chamber, type of burner, installation method, presence of a pump and expansion tank, automatic boiler control.

To determine required power gas heating boiler for private country house or apartment used simple formula- 1 kW of boiler power for heating 10 m 2 of a well-insulated room with a ceiling height of up to 3 m. If heating a basement, glassed-in winter garden, rooms with non-standard ceilings, etc. is required. The power of the gas boiler must be increased. It is also necessary to increase the power (about 20-50%) when providing a gas boiler and hot water supply (especially if it is necessary to heat the water in the pool).

Feature of power calculation for gas boilers: the nominal gas pressure at which the boiler operates at 100% of the power declared by the manufacturer, for most boilers is from 13 to 20 mbar, and the actual pressure in gas networks in Russia can be 10 mbar, and sometimes lower . Accordingly, a gas boiler often operates at only 2/3 of its capacity and this must be taken into account when calculating. For more details, see the table for calculating the power of a heating boiler.

Most gas boilers can be convert from natural gas to liquefied gas(cylindered propane). Many models switch to liquefied gas at the factory (when purchasing, check these characteristics of the model), or the gas boiler is additionally supplied with nozzles (nozzles) for switching to bottled gas.

Pros and cons of gas boilers:

Boiler piping- These are devices for the full operation of the heating and water supply system. It includes: pumps, expansion tanks, filters (if necessary), manifolds, check and safety valves, air valves, valves, etc. You will also need to purchase radiators, connecting pipes and valves, thermostats, boiler, etc. The issue of choosing a boiler is quite serious, so it is better to entrust the selection of equipment and its complete set to professionals.

Which boiler is the best? On Russian market gas boiler equipment has its own leaders in quality and reliability. The best manufacturing companies and brands of gas boilers are presented in an assortment:

"Premium class" or "Lux"- the most reliable and durable, easy to use, the kit is assembled like a “construction set”, more expensive than others. Such manufacturers include German companies

Giving preference offline methods heating, homeowners want to solve the problem of heating an apartment or house once and for all. Independent heating not only provides optimal temperature conditions in residential premises, but also provides significant cost savings in the family budget. It’s up to you to decide which type of autonomous heating you prefer. First, let's get acquainted with the main existing home heating options, based on the energy they consume:

• Electrical devices.
• Solid fuel devices.
• Liquid fuel units.
• Gas appliances.

Each of the listed groups is divided into subgroups according to the installation method, the coolant used, the area of ​​application, etc. But to this list of devices used as the main means of heating a home, it is necessary to add systems involved in the heating process as additional devices, increasing comfort temperature regime in room. Such systems include so-called heated floors, electric and water.

Of particular interest in this regard is a water heated floor, operating from a gas boiler - an autonomous hot water generator. The system is relatively new, but has been sufficiently studied and is superior in efficiency to devices such as, for example, heated fans.

Warm floor - idea and concept

The idea of ​​installing heated floors in residential premises is not new. Man has long paid attention to the laws of physics operating around us - warm air in a room always accumulates at the top, under the ceiling. The cooled air, on the contrary, sinks down, making the floor the coldest place in the room, eating up precious kilocalories with its large area.

Artificially heated to certain temperature the floor becomes a powerful source of heat in the room. Due to large area heating, the air warms up evenly and rises, filling the entire internal space. The air exchange process ensures the required temperature in the room, and minimizes the difference between its values ​​at the floor level and at the ceiling. In rooms equipped with heated floors, there are practically no areas with cool air.

Gas boilers used today for home autonomous heating are quite capable of providing normal work warm water floor. It is possible to achieve an effective increase in comfort in this situation if certain conditions are met - accurate thermal and hydraulic calculations, competent installation of the underfloor heating system.

Concept

Floor heating can be ensured by laying a pipeline in the existing space between the floor and the floor covering, in which the coolant heated by the gas boiler will circulate. The coolant is water (ordinary or with special additives antifreeze) is a traditional liquid used for autonomous boiler equipment.

The heat exchanger in this case is a pipeline laid under the floor covering. The effect is achieved due to the large heat transfer area. The amount of heat entering the interior space is sufficient for the horizontal and vertical distribution of warm air mass.

Important! The fundamental difference between this system and other types of heating systems is the low temperature of the coolant. For a warm water floor, it is enough to heat the coolant to a temperature of 30-50 0 C.

Components of the “warm water floor” system

The main structural elements of such a system are:

• a gas boiler;
• injection pump;
• shut-off valves and connecting fittings;
• the main pipeline for distributing coolant through residential premises;
• floor mini-pipeline for laying on the surface of the subfloor;
• collector;
• system of automation and adjustment of operating modes.

A gas boiler

For a private house with a large area, where it is planned to increase the comfort of the temperature regime in a large number of rooms, the optimal choice would be a floor-mounted double-circuit gas boiler in an autonomous design. Such units have great power and are capable of simultaneously solving several problems at once - heating residential premises and providing hot water supply.

On a note: For floor-mounted gas heating equipment, it is necessary to equip an appropriate room with a chimney and ventilation. The room allocated for the boiler room (boiler power up to 30 kW) must have an area of ​​at least 4 square meters, and a minimum volume of 8 cubic meters. If a single-circuit gas boiler is used for underfloor heating, then for the hot water supply system you will have to additionally install an indirect heating boiler, which can be placed in the same room.

For an apartment where everyone is precious square meter area, you can use a wall-mounted gas boiler, which, with the correct selection of power, will also ensure the efficient operation of water heated floors. Due to their dimensions, it is easier to find a place to place such equipment; wall-mounted gas boilers can be installed even in the kitchen or bathroom. Typically varies in the range of 7-30 kW.

Wall-mounted freestanding gas appliances in most cases they have a closed combustion chamber, so for its efficient and safe operation it is enough to equip a coaxial chimney with access to the street or to the central chimney shaft.

An important point when purchasing equipment is to determine the optimal power of the gas boiler, which will have to ensure the operation of the “water heated floor” system, therefore, when choosing a gas boiler model, it is necessary to rely on thermal calculation data.

For reference: for heating 1 sq. m of living space requires approximately 100 W of electricity, provided the room is well insulated, ceilings are no more than 3 m high and there are no excess windows.

Most premises of a private house have external walls in their design, heat loss through which may require an increase of up to 150 W in heat costs to heat 1 square meter. living space. Therefore, when purchasing a gas boiler, even having a thermal calculation indicating the required power of the unit, it is better to purchase a device that exceeds the calculated value of this characteristic by 15-20%.

In most cases, the power of double-circuit boilers is designed for hot water supply with one or two water intake points. Therefore, with an increase in the number of hot water intake points, an increase in boiler power will be required.

In this regard, a water heated floor has an advantage - it loads a gas boiler in a gentle mode. The principle of operation of the underfloor heating system in this situation requires minimal energy consumption from the boiler to heat the coolant. Most of the boiler power is released to heat the water in the hot water supply system.

Pipes for water heated floors

To lay a warm water floor, copper, polypropylene, metal-plastic or PEX pipes are used.

Copper pipes (high thermal conductivity, durability) are the ideal material for installing water-heated floors, so their price is high and availability is limited.

Polypropylene pipes are also not very common, but for a different reason - their flexibility is insufficient, and the minimum bending radius of the pipe must be equal to 8 of its diameters, which moves the turns away from each other.

Metal-plastic pipes are deservedly popular - the internal aluminum coating provides them with good thermal conductivity, and the polymer shells protect them from damage. With such characteristics, an affordable price is a good incentive to choose them.

PEX pipes are a material made of “cross-linked” polyethylene, that is, with an artificially modified molecular structure that makes this material strong and durable. The price of PEX pipes is quite affordable, and therefore their use in the construction of water-heated floors is widespread. However, one specific property of this material should be kept in mind - PEX pipes, when heated, tend to take on their original contour, therefore, when laying on the floor, they must be firmly fixed to the screed reinforcement.

The heating system is not installed in one day, so its reliability, including tightness, and durability must be ensured. For this purpose, pipes are laid in a single solid coil, without joints. The task is to obtain a single, closed circuit during the installation process through which the coolant will circulate, for which it is better to use water with special additives. This will prevent the system from defrosting during severe frosts. This measure is relevant for owners of country houses and cottages with temporary residence.

Important! When using water in the system, it is necessary to install an additional protective device, a compressor or a compressed air cylinder for emergency purging of the entire circuit and draining the coolant.

Important! When buying pipes for a heating system, pay attention to the markings. Products intended for heating systems have corresponding symbols and designations. As a rule, this permissible pressure is 10 bar and the heating temperature is up to 95 0 C.

Depending on the characteristics of the room and the type of floor covering (screed thickness, room height, etc.), pipes with a diameter of 16-20 mm are used to install a warm water floor system. During pipeline installation, a minimum bending radius is allowed, equal to five times the diameter for metal-plastic pipes and 8 times for polypropylene material.

To complete the picture, we suggest that you familiarize yourself with the video material, which describes and shows in detail how the installation of a water heated floor is carried out.

Installation of a water heated floor system

The installation of a water heated floor system begins with preparing the base, which includes several operations, which we will now briefly consider. Failure to comply with the requirements for the subfloor on which the heated floor is installed is fraught with, at a minimum, a decrease in the efficiency of its operation, and at a maximum, depressurization followed by expensive major repairs.

Preparing the base

The foundation must be prepared accordingly before laying the pipeline. The base surface must be hard, clean and level. Height differences are allowed in the range of plus or minus 10 mm per meter of linear length. If the floor surface does not meet the requirements, has a large curvature and obvious flaws, a leveling screed is installed, followed by waterproofing of the base in case of depressurization of the system.

Before laying the pipeline, the subfloor is also insulated. For these purposes, slabs of extruded polystyrene foam or basalt fiber with a thickness of 30-50 mm are used.

If you have a sufficient budget, it is justified to use slabs shielded with foil and equipped with special protrusions for convenient pipe laying. Such measures are resorted to to reduce heat losses through the floor in rooms on the first floor - a warm floor together with a gas boiler of any power will work with increased load simultaneously with floor heating to heat the basement or someone else's apartment on the floor below.

Important! Before pouring cement mortar, it is necessary to stick a strip of damper tape 5 mm thick and a width equal to the thickness of the layer of mortar being poured around the perimeter of the room on the walls. The tape will compensate for the thermal expansion of the screed and reduce its pressure on vertical structures.

Installation

Based on their design and, accordingly, installation method, water heated floor systems are divided into 2 types:

• concrete (poured);
• flooring

In the first case, we are talking about pouring concrete on the contour of a water-heated floor system laid on a prepared base. This operation is preceded by dividing the base into sections and laying the reinforcing mesh.

The following types of installation of heat pipes are used:

• snake;
• double snake;
• spiral;
• offset spiral;
• combined method.

The diagram shows how a heating circuit is installed in a room with increased heat loss - two or more external walls.

Important! After the installation of the underfloor heating system is completed, it is pressure tested under a pressure of 5 Bar for 24 hours.

The concrete screed acts as an additional element participating in the heat distribution process. Considering bad job tensile concrete, it is laid at a pressure in the heat pipe system of 3 bar, reducing the tensile load with further supply of water to the operating pressure.

For the screed mortar, cement of a grade not lower than M-300 is used, and its thickness should be 30-50 mm, while the layer of mortar above the heat pipes should not be more than 2 cm.

When installing a water heated floor system, one should take into account a technological limitation - the finished floor covering must have a high thermal conductivity coefficient in order to transfer heat to the room air with minimal losses. That is, laying linoleum, laminate, parquet, or plank flooring over a warm floor is impractical due to the high heat-insulating properties of these materials. And laying over a tile system, especially with high density - porcelain stoneware, natural stone, broom is not only justified, but also advisable due to the constantly cold surface of such finishing.

The laying method is used in rooms where the use of screed is undesirable due to low ceilings, or production concrete works is fraught with moisture leakage into the lower or adjoining rooms. The limitation may be a seasonal factor or related to the design features of the building. The main advantage of decking systems is high speed their installation. Warm water floors of the laying type, based on the materials of the system, are divided into:

• polystyrene;
• wooden:

• modular;
• rack and pinion

All these types of flooring systems are characterized by less labor intensity and the absence of significant contamination of the home during the installation process.

Polystyrene heated floors

This system is a set of heat-insulating coating made of extruded polystyrene foam (expanded polystyrene), heat pipes and heat-distributing aluminum plates.

Polystyrene slabs are laid on the load-bearing base, on top of which heat conductor pipes are mounted on aluminum plates with special grooves.

On top of the aluminum plates, the floor is finished with a material with a high thermal conductivity coefficient (for example, ceramic tile with 2-component epoxy adhesive).

Wooden underfloor heating systems

These devices are mounted on existing wooden floors or wood joists.

The modular variety uses plates (modules) with channels and grooves for heat-distributing plates and pipes.

In the slatted subtype of heated floors, the installation of modules is carried out between existing ones on a hard surface. rough floor logs, or logs are pre-installed for this purpose. These structures play the role of stiffening ribs for the heated water floor being installed and its subsequent finishing; the list of structural elements does not differ from the modular type.

After finishing the installation of heated floors, the system is also pressure tested and commissioning works (checking tightness, tightening connections).

The laying method of installing a heated floor system is universal and applicable in almost all buildings and structures. However, its advantages are reflected in the cost, which is quite high.

Conclusion

A competent project combined with qualified installation of equipment is a guarantee positive result. A water heated floor, which you will use as an additional home autonomous heating system, will be an effective, economical and practical device that significantly increases the comfort of your home.

Warm floors are considered, in our understanding, to be a more modern heating system than radiator heating. However, this is far from true - they appeared much earlier. Stubborn historical facts indicate that heated floors were successfully used back in the days of Ancient Rome, in Korea, and in Russia too. True, it was only used then stove heating, since the system for transporting hydrocarbons through pipes did not yet exist. In the modern world, the most economically successful countries widely use heating warm floors, and this is done not only for reasons of obvious comfort, but also takes into account the fact that such heating allows saving energy resources, the demand for which is growing every year.

This type of heating is not a cheap pleasure. Parts and labor are very expensive. That's why anyone zealous owner You may be thinking about making a water heated floor with your own hands. Why not? Moreover, the experience of both successful and unsuccessful implementations has already been accumulated enough to give specific recommendations. The purpose of our article is to give specific advice to those owners who are going to make a warm water floor, but at the same time so that they save their money and ultimately get what they wanted - comfortable and economical heating.

Of course, they are simpler to implement and easier to manage, but the cost of energy makes its own adjustments - this type of heating is much more expensive to operate than a water-heated floor. Only 4-5 years will pass and the warm water floor will pay for itself with interest, but only on the condition that it is done competently and correctly. This is exactly what the authors of the article want to tell our readers. Disregarding colorful catalogs with expensive equipment, and based only on the experience of people who were able to implement a warm water floor in their home.

Most heating systems currently use natural gas as a heat source - and this makes perfect sense, since this type of fuel is cheaper than others. And this trend will continue for at least several more decades. Therefore, it is best to implement heated floors with water, in which the coolant is heated by the energy of combustion of natural gas. But for this, a number of conditions must be met.

Water heated floor installation

A warm water floor is a complex multi-component system, each part of which performs its own function. Let's look at its structure in the following figure.

Typical design of a “pie” of a warm water floor

This type of underfloor heating is called “wet” because it uses “wet” construction processes, namely pouring a cement-sand screed. There are also so-called dry heated floors, but they are made mainly. In this article, we will consider “wet” warm water floors, since they are much better, although their installation is more difficult.

A warm water floor is mounted on a stable and durable base, which can be concrete slab or soil. A vapor barrier made of polyethylene film with a thickness of at least 0.1 mm is laid on the base. Next layer The “pie” is insulation; it is best to use extruded insulation, which has a very low thermal conductivity coefficient, high mechanical strength and reasonable cost. On top of the insulation is equipped cement-sand screed, to which a plasticizer is necessarily added - for the mobility of the mixture, ease of installation and reduction of the water-cement ratio. It is advisable to reinforce the screed with metal wire mesh with a cell pitch of 50*50 mm or 100*100 mm. There, inside the screed, there are underfloor heating pipes with coolant circulating in them. It is recommended to make the height of the screed above the pipes at least 3 cm, however, practice suggests that 5 cm is better, as the strength will be higher and the heat distribution across the floor will be more uniform.

At the junction of the walls and the screed, as well as at the boundaries of the warm water heating circuits, a damper tape is laid, which compensates for the thermal expansion of the screed when it is heated. Finish coating the floor must be designed specifically for working with heated floors. The best solution is ceramic or porcelain tiles, but some other types of coverings - laminate, carpet or can also be used with heated floors, but they must have a special symbol in their markings.

Such coatings, however, require strict adherence thermal regime floor, which is achieved by using automation - special mixing units.

Requirements for premises where heating with warm water floors will be implemented

The smartest move in construction is when the underfloor heating pipeline is laid at the stage of erecting the floors. This is very successfully used in Germany, Sweden, Norway, Canada, and in other economically successful countries where energy resources are very expensive and therefore they use underfloor heating, which is 30-40% more economical than radiator heating. It is quite possible already in ready premises, but it must meet certain requirements. Let's list them.

The most correct underfloor heating pipeline is the one that was laid during the construction of the house

• Considering the significant thickness of the warm water floor - from 8 to 20 cm, the height of the ceilings in the room should allow the installation of such a heating system. It is also necessary to take into account the size of the doorways, which must be at least 210 cm in height.
• The base of the floor must be strong enough to withstand a heavy cement-sand screed.
• The base for heated floors must be clean and level. Irregularities should not exceed 5 mm, since differences greatly affect the coolant current in the pipes; they can lead to airing of the circuits and an increase in hydraulic resistance.
• In the room where a warm water floor is planned, all plastering work, windows installed.
• Heat loss in the premises should not be more than 100 W/m2. If they are larger, then you should think about insulation rather than heating the environment.

How to choose a good pipe for heated floors

Warm water floor pipes are written in sufficient detail on our portal. Obviously, for heated floors it is better to choose pipes made of cross-linked polyethylene - PEX or PERT. Among PEX pipes, preference should be given to PE-Xa pipes, since they have a maximum cross-linking density of about 85% and therefore have the best “memory effect”, that is, pipes, after being stretched, always tend to return to their original position. This allows the use of axial fittings with a sliding ring, which can be walled into building structures without fear. In addition, if a pipe is broken, its shape can be restored by heating problem area construction hairdryer.

PERT pipes do not have a memory effect, so only push-in fittings are used with them, which cannot be walled up. But if all the contours of the heated floor are made with solid pipe sections, then all connections will be only on the manifold and it is quite possible to use PERT pipes.

In addition, manufacturers produce pipes composite construction, when between two layers of cross-linked polyethylene is placed aluminium foil, which is a reliable oxygen barrier. But the heterogeneity of the material and the difference in the coefficients of thermal expansion of aluminum and polyethylene can provoke delamination of the pipe. Therefore, it is better to choose PE-Xa or PERT pipes with a polyvinylethylene (EVOH) barrier, which significantly reduces the diffusion of oxygen into the coolant through the pipe wall. This barrier can be located in the outer layer of the pipe, or inside, surrounded by layers of PE-Xa or PERT. Of course, the better pipe is the one with the EVOH layer inside.

For underfloor heating circuits, there are three main pipe sizes: 16*2 mm, 17*2 mm and 20*2 mm. Most often they use 16*2 and 20*2 mm. How to choose exactly the “right” pipe.

• Firstly, the brand matters in this matter and you need to pay attention to it. The most famous manufacturers: Rehau, Tece, KAN, Uponor, Valtec.
• Secondly, the marking of pipes can “tell” a lot; it should be carefully studied and do not hesitate to ask more questions to the sales consultant.
• Thirdly, the qualifications of the sales consultant are very helpful when choosing a pipe. Don’t forget to ask for certificates of conformity, inquire about the availability and price of fittings, mixing units, manifolds and other equipment. It is necessary to find out in which coils the pipe is sold, and how many meters, in order to take this into account in future calculations.
• And finally, if a PE-Xa pipe is selected, then you can conduct a small test. To do this, you need to bend a small section of pipe, and then warm up this place with a hair dryer. A high-quality PE-Xa and PE-Xb pipe should also restore its original shape. If this does not happen, then no matter what is written on the label, it is simply not a PEX pipe.

Principles of designing heated floors

One of the most important stages in the arrangement of warm water floors is their proper calculation. Of course, it is best to entrust this to specialists, but sufficient experience already suggests that this can be done independently. You can find a lot of free programs and online calculators on the Internet. Most reputable manufacturers provide their software for free.

water heated floor

First you need to decide what temperature the heated floor should be.

• In residential areas where people spend most of their time standing, the floor temperature should be in the range of 21 to 27°C. This temperature is most comfortable for the feet.
• For work areas - offices, as well as living rooms, the temperature should be maintained around 29°C.
• In hallways, lobbies and corridors, the optimal temperature is 30°C.
• For bathrooms and swimming pools, the floor temperature should be higher - about 31-33°C.

Heating with warm water floors is low-temperature, therefore the coolant must be supplied at lower temperatures than to radiators. If water can be supplied to the radiators at a temperature of 80-90°C, then the heated floor cannot be supplied at more than 60°C. In heat engineering there is such an important concept as temperature drop in the heating circuit . This is nothing more than the difference in temperature between the supply pipe and the return pipe. In heated water floor systems optimal modes considered to be 55/45°C, 50/40°C, 45/35°C and 40/30°C.

A very important indicator is (loops) of a warm water floor. Ideally, they should all be the same length, then problems with balancing will not arise, but in practice this is unlikely to be achieved, so it is accepted:

• For a pipe with a diameter of 16 mm, the maximum length is 70-90 m.
• For a pipe with a diameter of 17 mm – 90-100 m.
• For a pipe with a diameter of 20 mm – 120 m.

Moreover, it is advisable to focus not on the upper limit, but on the lower one. It is better to divide the room into large quantity loops rather than trying to achieve more circulation powerful pump. Naturally, all loops must be made of pipes of the same diameter.

Step of laying out (laying) heated floor pipes - another important indicator, which is made from 100 mm to 600 mm, depending on the thermal load on the heated floor, the purpose of the room, the length of the circuit and other indicators. It is almost impossible to make a pitch of less than 100 mm with PEX pipes; there is a high probability of simply breaking the pipe. If the heated floor is equipped only for comfort or additional heating, then you can make a minimum step of 150 mm. So, what layout step should be used?

• In rooms where there are external walls, underfloor heating do so-called edge zones , where pipes are laid in increments of 100-150 mm. In this case, the number of rows of pipes in these zones should be 5-6.
• In the centers of rooms, as well as in those where there are no external walls, the laying step is 200-300 mm.
• Bathrooms, baths, paths near swimming pools are laid with pipes with a pitch of 150 mm over the entire area.

Methods for laying heated floor contours

The contours of a water heated floor can be laid in different ways. And each method has its advantages and disadvantages. Let's look at them.

• Laying a heated floor pipe in a “snake” pattern easier to install, but its significant drawback is that there will be a noticeable temperature difference on the floor at the beginning of the circuit and at the end - up to 5-10°C. The coolant, passing from the supply manifold to the return manifold in the heated floor structure, cools down. Therefore, such a temperature gradient arises, which is clearly felt by the feet. This installation method is justified in boundary zones, where the floor temperature should decrease from the outer wall to the center of the room.

• Laying a heated floor pipe "snail" more difficult to implement, but with this method the temperature of the entire floor will be approximately equal, since the supply and return pass inside each other, and the difference is leveled out by a massive floor screed when the calculated requirements of the laying step are met. In 90% of cases this method is used.

• Combined methods of laying underfloor heating pipes are also used very often. For example, the edge zones are laid with a snake, and the main area with a snail. This can help to correctly divide the room into contours, distribute the pipe coil with a minimum of residue and ensure the desired mode.

In each of the methods it can be used variable laying step , when in the edge zones it is 100-150 mm, and in the room itself 200-300 mm. Then it is possible to meet the requirements for more intense heating of the edge zones in one room without using other installation methods. Experienced installers most often do just this.

Layout of the heating circuit “snail” with a constant pitch (left) and with a variable pitch (right)

To calculate contours, it is best to use a special and very easy to learn software. For example, famous manufacturer Valtec, which distributes its program for free. There are also simpler programs for calculating the layout of contours that calculate the length of the loops, which is very convenient. For example, the “Snail” program, which is also distributed free of charge. For those who are not very computer friendly, you can calculate the contours yourself by using graph paper, on which you can draw a floor plan to scale and, on this sheet, “lay out” the contours with a pencil and calculate their length.

When dividing rooms into water-heated floor circuits, the following requirements must be met:

• The circuits should not move from room to room - all rooms should be regulated separately. An exception may be bathrooms if they are located nearby. For example, a bathroom next to a toilet.
• One heating circuit should not heat a room with an area of ​​more than 40 m2. If necessary, the room is divided into several circuits. Maximum length any side of the contour should not exceed 8 meters.
• A special damper tape must be laid along the perimeter of the room, between rooms, as well as between individual circuits, which, after pouring the screed, will compensate for its thermal expansion.

Choosing the type of insulation for a heated floor and its thickness

Insulation for a warm water floor is mandatory, because no one would like to spend their money on heating the ground, the atmosphere or unnecessary building structures, but the floor is exactly what is needed, which should receive the lion's share of the heat from the heating circuit. This is why insulation is used. What types should be used? Among all their diversity, the authors of the article recommend that you should pay attention to only two of them.

• Extruded polystyrene foam (EPS). This material has low thermal conductivity and high mechanical strength. EPS is not afraid of moisture, it practically does not absorb it. Its price is quite affordable. This insulation is produced in the form of slabs standard sizes 500*1000 mm or 600*1250 mm and thickness 20, 30, 50. 80 or 100 mm. For good joining of the plates there are special grooves on the side surfaces.

• Profile thermal insulation made of high-density polystyrene foam. On their surface there are special round or rectangular bosses, between which it is very convenient to lay the pipe without additional fixation. The pipe fastening pitch is usually 50 mm. This is very convenient for installation, but the price is much higher than EPS boards, especially from famous brands. They are produced with a thickness of 1 to 3 cm and dimensions of 500 * 1000 mm or 60 * 1200 mm - it depends on the manufacturer.

Eps boards may have an additional foil layer with additional markings. Marking the slabs is, of course, useful, but the presence of foil only increases the cost of the insulation, and it will be of no use for two reasons.

• The reflectivity declared by the manufacturers will not work in an opaque environment, such as a screed.
• Cement mortar is a strong alkaline environment, which will perfectly “eat” an insignificant (several tens of microns) layer of aluminum before it hardens. You need to realize that foil plates are marketing ploy and no more.

The authors of the article recommend using EPS boards for insulation. The savings compared to profile mats will be obvious. The difference in cost will be enough for fasteners, and there will still be a lot of money left over. Let's remember folk wisdom that money saved is similar to money earned.

How thick should the insulation be in the construction of a warm water floor? There are special and complex calculations, but you can do without them. If you learn a few simple rules.

• If heated floors will be made on the ground, then the thickness of the insulation should be at least 100 mm. It is best to make two layers of 50 mm each and lay them in mutually perpendicular directions.
• If heated floors are planned in rooms above ground floor, then the thickness of the insulation is at least 50 mm.
• If heated floors are planned above rooms heated from below, then the thickness of the insulation is at least 30 mm.

Additionally, it is necessary to provide for fastening the EPS boards to the base material, since when pouring the screed they will tend to float. Disc-shaped dowels are ideal for this. They must be used to secure all slabs at the joints and in the center.

To attach the pipe to the EPS, special harpoon clamps are used, which securely fix the pipe. They are fastened at intervals of 30-50 cm, and in places where the PEX pipe turns, the step should be 10 cm. It is usually calculated that 500 pieces of harpoon clamps are required for a bay of 200 meters of pipe. When purchasing them, there is no need to chase the brand, as it will cost several times more. There are very high-quality and inexpensive staples from Russian manufacturers.

Selecting a collector-mixing unit for heated floors

The water floor collector is the most important element that receives coolant from the main, distributes it among the circuits, regulates flow and temperature, balances circuit loops, and promotes air removal. Not a single warm water floor can do without it.

It is better to entrust the choice of a collector, or, more correctly, a collector-mixing unit, to specialists who will select the necessary components. In principle, you can assemble it yourself, but this is a topic for a separate article. We’ll just list what elements should be included so as not to make a mistake in choosing.

• Firstly, these are the collectors themselves, which can be equipped with various fittings. They must be equipped with tuning (balancing) valves with or without flow meters, which are placed on the supply manifold, and on the return manifold there may be thermostatic valves or simply shut-off valves.

• Secondly, any manifold for removing air from the system must be equipped with an automatic air vent.
• Thirdly, both the supply and return manifolds must have drain valves to drain the coolant from the manifold and remove air when the system is filling.
• Fourthly, to connect the pipe to the collector, fittings must be used, which are selected individually in each specific case.

• Fifthly, special brackets are used to fasten the collectors and ensure the required center distance.

• Sixth, if the boiler room is not equipped with a separate riser for heated floors, then a mixing unit, including a pump, thermostatic valve, and bypass, must be responsible for preparing the coolant. The design of this node has many implementations, so this issue will be discussed in a separate article.

• And finally, the entire collector-mixing unit must be located in a collector cabinet, which is installed either in a niche or openly.

The collector-mixing unit is located in such a place that all the lengths of the lines from it to the heated floor loops are approximately equal and main pipes were in close proximity. The manifold cabinet is often hidden in a niche, then it can be placed not only in change houses and boiler rooms, but in dressing rooms, corridors and even living rooms.

Video: What calculations are necessary before installing a heated floor

Do-it-yourself water heated floor installation

After making calculations and purchasing all the necessary components, you can gradually implement a warm water floor. First, it is necessary to outline the places where the manifold cabinets will be placed, hollow out niches if necessary, and also make passages through building structures. All slotting and drilling work must be completed before the next stage.

Installation of insulation

Before this stage, it is necessary to prepare the premises for this - take out everything unnecessary, remove all construction garbage, sweep and vacuum the floors. The room must be absolutely clean. When installing slabs, you must wear shoes with flat soles, as heels can damage the surface. We list the sequence of actions when installing insulation.

• First of all, the level of the clean floor is marked on the walls using a laser or water. All base irregularities are measured using a long rule and a level.
• If the unevenness exceeds 10 mm, then they can be completely leveled by adding clean and dry sand, which should subsequently be leveled.

• If the heated floor is made on the ground or above the basement floor, then a waterproofing film is spread with an overlap of adjacent strips of at least 10 cm and overlapping the wall. The joints are taped with tape. Suitable for waterproofing polyethylene film 150-200 microns.
• Starting from the far corner of the room, the process of laying EPS boards begins. They are laid close to the walls with the marked surface facing up.
• The EPS boards must fit tightly together using grooves on their side surfaces. When laying each slab, it should fit tightly to the base and be in horizontal plane, which is checked by the building level. If necessary, add sand under the slab.

• If along the laying path there are obstacles in the form of protrusions, columns and other elements, then after preliminary marking the slab is trimmed with a construction knife along a metal ruler. In this case, the EPS must be placed on some kind of non-solid base so that the knife does not become dull, for example, a piece of plywood or OSB.
• When laying next row It should be taken into account that the joints of the plates should not coincide, but run apart, like brickwork. In order to ensure that at least 1/3 of its length remains from the last remaining EPS slab in a row, then laying the next row should begin with it.
• If it is planned to lay the second layer of EPS, then it should be laid in a mutually perpendicular direction with the first layer.
• After laying the thermal insulation, use a hammer drill with a long drill and a hammer to secure the disc dowels at each joint - at each joint and in the center of each EPS board. The joints between the EPS are sealed with construction tape.

• If after installing the insulation there are cavities or cracks left, they can be filled with EPS cuttings and blown out polyurethane foam, but this can be done later, after the pipes have been installed.

After this, we can say that the installation of insulation has been completed. Although EPS boards are dense enough to support the weight of an adult, you still need to take precautions when moving on them. It is best to use wide boards or pieces of plywood or OSB.

Installation of a warm water floor pipe

The most crucial and difficult moment has arrived - installation of underfloor heating pipes. At this stage you need to be especially attentive and careful, and you can’t do it without an assistant. It is also advisable to have special device for unwinding the pipe, since it is strictly forbidden to remove the pipe from the coil with rings, since then there will be very strong stresses in it, which will complicate or make installation impossible. The main rule is that the coil must be twisted, and not removed from the fixed coil. In principle, this can be done manually, but with a device it is much easier.

If there are markings on the top side of the EPS slabs, then this is simply wonderful, then laying the pipes will be greatly simplified. And if not, then you shouldn’t go for the purchase of thin foil insulation made of foamed polyethylene with markings applied. It won't be of any use. You can apply the markings yourself. To do this, marks are made with a marker on the top side of the slabs at the distance of the required contour step, and then the lines are marked with paint thread - this way you can make markings in a short time. After this, you can draw the routes of the heated floor contours.

screed for heated floors

A manifold cabinet is attached to the intended location and a manifold is mounted in it, without a pumping and mixing group for now, it will be needed later. At the entrance to the collector, at the exit from it, and also at the entrance to the pipe, each pipe must be protected with a special corrugation. However, corrugation from famous manufacturers costs mind-boggling money, so it is quite acceptable to replace it with thermal insulation of the appropriate diameter. Also, pipes must be protected during transitions from room to room and from circuit to circuit.

Installation of underfloor heating pipes should begin from the areas furthest from the collectors, and all transit pipes should be covered with thermal insulation made of foamed polyethylene, which will ensure maximum energy conservation to the destination point and will not “lose” heat along the way. Next, the pipe “emerges” from the EPS slabs, already “naked” it bypasses its entire heating circuit and “dives” back and, already in thermal insulation, follows to the collector. The transit pipes themselves are placed inside the EPS slabs; for this, passage routes are first cut into them with a knife.

If the thermal insulation consists of two layers of EPS boards, then the first layer is laid first, then all communications are laid, including transit pipes for the heated floor, and then the second layer is adjusted and trimmed on site.

In addition, in the area where the heated floor is located, pipes to radiators, as well as hot and cold water supply lines, can run. If there are several pipes, then they can be secured in a bundle either with disc dowels or with a perforated metal strip and dowels. In any case, they should not protrude beyond the top surface of the EPS slabs, so that the heated floor contour can be laid on top without any obstruction. All cavities are filled with polyurethane foam, which, after hardening, is cut flush from the surface of the insulation boards.

Along the perimeter of the room where there will be heated floors, a damper tape is glued to the walls, which is designed to compensate for the thermal expansion of the screed. The tape comes with or without an adhesive layer. When purchasing it, you don’t have to chase the brand and pay several times more. A damper tape that is worthy in every sense is now being produced Russian production. If there is no tape at all, then this is also not a problem - it can be replaced by foam plastic 1 or 2 cm thick, glued to the wall with liquid nails or polyurethane foam.

Damper tape should also be installed between rooms and different circuits. For this purpose it is produced special tape With T-profile. And in this case, it can be replaced by thin foam plastic glued with polyurethane foam or glue.

Pipe installation is done as follows:

• 10-15 m of pipe is unwound from the coil, thermal insulation and a corresponding fitting for connection to the collector are put on its end.
• The pipe is connected to the supply of the corresponding outlet of the manifold.
• The pipe is laid along previously marked routes and secured with harpoon clamps on straight sections after 30-40 cm, and on turns after 10-15 cm. The pipe should be bent carefully, without creases.

• When laying, you should not try to fasten the pipe immediately, but should first lay it out approximately along the routes for 5-10 m, and only then fasten it with brackets. The pipe should lie on the insulation without tension, there should be no force that tries to pull the staples out of the EPS.
• If for some reason the bracket has flown out of its place, then it is mounted in another place, at a distance of at least 5 cm.
• After bypassing the entire circuit of the heated floor, return pipe returns to his server and follows her next to the collector. If necessary, thermal insulation is put on it.
• Upon arrival at the collector, the pipe is connected to it with the appropriate fitting.

• Near the corresponding loop of the heated floor on the wall, as well as on paper, the length of the contour must be written down. This data is necessary for further balancing.

All contours are laid in the same way. At first it will be difficult, but then, after one “snail” has been laid, everything will be clear and the work will go without problems. When moving along already laid contours, you need to lay boards, plywood or OSB under your feet or knees.

Video: Laying a heated floor pipe

Installation of reinforcing mesh

Disputes about the appropriateness of reinforcing mesh are ongoing. Some say that it is needed, others say the opposite. There are many examples of successful implementation of a heated floor without a reinforcing mesh and, at the same time, there are examples of unsuccessful implementation of a heated floor with reinforcement. The authors of the article claim that reinforcement will never be superfluous, but only if done correctly.

The Internet is replete with examples where a metal mesh is laid and secured onto the insulation, and only then a heated floor pipe is attached to it using plastic ties. It seems convenient, but this is not reinforcement, but simply placing an absolutely useless mesh under the screed, on which money was spent. Reinforcement is when the mesh is inside the screed and not under it. This is why the authors recommend placing the mesh on top of the pipe.

To reinforce the screed, a metal mesh made of wire with a diameter of 3 mm with a cell size of 100 * 100 mm is suitable - this is quite enough. It is not recommended to use mesh made from reinforcement due to the fact that the reinforcement has a corrugated surface and during installation can damage the smooth surface of the pipe. And you shouldn’t spend extra money on the excessive strength of the screed, because it is assumed that the heated floor is already installed on a fairly solid foundation. The mesh is laid overlapping one cell and tied either with knitting wire or plastic clamps. The sharp protruding ends must be bitten off so that they do not damage the pipe. Additionally, the mesh is attached to the pipe in several places with plastic clamps.

Instead of a metal mesh, a plastic mesh can be used, which will perfectly reinforce the screed and save it from cracking. It is more convenient to lay plastic mesh, as it comes in rolls. The use of plastic mesh virtually eliminates damage to pipes, and its cost is significantly lower.

After laying the mesh, the question of protecting the pipes again arises, because when moving in shoes on a metal mesh, you can easily damage both it and the pipe. Therefore, it is again recommended to move only on boards, plywood or OSB. But there is also a very smart solution that will avoid damage to pipes when pouring screed.

A cement mortar is prepared - the same as it will be when laying the screed (1 part M400 cement and 3 parts sand) and during the laying process, “lappers” are made from the mortar, which protrude slightly beyond the surface of the mesh - 2 cm is enough. These “slips” are made at such a frequency (30-50 cm) that will allow you to later put boards or plywood on them and move around completely safely. Another advantage of this approach is the fixation of the mesh, because when walking on it it tends to bend, and this can damage the welds.

“Bands” from the solution will fix the mesh and help you move safely

Filling the contours. Hydraulic tests

This operation should definitely be carried out before pouring the screed, since in case of a hidden fault it is easier to eliminate it immediately than after the floors have been poured. To do this, a hose is connected to the drain pipe on the manifold and discharged into the sewer, since a lot of water will be spilled through the heating circuits. It is best if the hose is transparent - this will make it easy to track the release of air bubbles.

Tap water is connected to the inlet of the supply manifold, which must be equipped with a shut-off ball valve, through a hose or pipe. If the quality tap water low, then it is worth filling the system through a mechanical filter. A pressure testing pump is connected to any other output connected to the underfloor heating circuits. This may be the free outlet of the supply manifold, the return outlet from the manifold, and other places - it all depends on the specific implementation of the collector unit. In the end, you can screw a tee into the ball shut-off valve of the supply manifold and use it to fill the system and perform pressure testing. After testing, the tee can be removed and the manifold connected to the supply line.

Filling the system is done as follows:

• On the collector, all the contours of the heated floor are covered, except for one. Automatic air vents must be open.
• Water is supplied and its purity and air output are monitored through the drain hose. On inner surface During pipe production, process grease and shavings may remain, which must be washed off with running water.
• After all the air has escaped and the water flows absolutely clean, turn off the drain valve, and then turn off the already flushed and filled circuit.
• All these operations are performed with all circuits.
• After flushing, removing air and filling all circuits, turn off the water supply valve.

If leaks are detected during the filling stage, they are eliminated immediately after the pressure is released. The result should be a system of warm water floors filled with clean coolant and de-aired.

To test the system, you will need a special tool - a pressure testing pump, which you can rent or invite an experienced technician who has such a device. Let us describe the sequence of actions during crimping.

• All underfloor heating circuits connected to the collector are fully opened.
• Pour into the container of the pressure testing pump pure water, the pump supply valve opens.
• The pump builds up pressure in the system twice as high as the working pressure - 6 atmospheres; it is controlled by the pump pressure gauge and on the manifold (if it has a pressure gauge).
• After raising the pressure, a visual inspection of all pipes and connections is carried out, which, in principle, should only be on the manifold. The pressure is also monitored using a pressure gauge.
• After 30 minutes, the pressure is again raised to 6 bar and all pipes and connections are again inspected. Then after 30 minutes these steps are repeated. If leaks are detected, they are repaired immediately after releasing the pressure.
• If no leaks are detected, then the pressure is again raised to 6 bar and the system is left for a day.
• If after 24 hours the pressure in the system has dropped by no more than 1.5 bar and no leaks are detected, then the underfloor heating system can be considered correctly installed and sealed.

When the pressure in the system increases, the pipe, according to all the laws of physics, will try to straighten out, so it is possible to “shoot off” some staples in those places where they were “greedy” with them. Therefore, “blobs” from the solution will greatly help to hold the pipe in place. In the future, when the screed is poured, the pipe will be securely fixed, but during pressure tests, a poorly secured pipe can present unpleasant surprises.

Video: Filling the system with coolant

Video: Pressure testing of a heated floor system

Installation of beacons

The heated floor screed must be poured through pipes under operating pressure. Considering that in most closed systems For heating, the operating pressure should be in the range of 1-3 bar; you can take the average value and leave a pressure of 2 bar in the circuits.

It is best to use plasterboard guide profiles PN 28*27/UD 28*27 as beacons. They have sufficient rigidity and a smooth top surface, which is very useful when leveling screeds.

Beacons should be installed at the level of the finished floor minus the thickness of the finishing floor covering. To secure them, very often they simply use mortar pads, on which a guide profile is laid, and then it is recessed according to the level. But this approach has the disadvantage that if the beacon falls below the required level, it has to be taken out, fresh solution added and set again.

It is best if the beacons made of a guide profile have a rigid support underneath, and concrete dowels and a screw of the appropriate length can serve as it. It is preferable to use special concrete screws - pins, which do not require the installation of a dowel, and, therefore, the drilling diameter will be smaller. If you need to drill a hole with a diameter of 10-12 mm for the dowel, then 6 mm is enough for the dowel. The top surface of the screw head should be level with the surface of the future screed.

Concrete screws - dowels

Beacons should be located at a distance of no more than 30 cm from the walls. There should not be a large distance between the beacons, since the solution tends to settle and a hole may form on the finished screed. Optimally - 1.5 m, then the construction rule of 2 m is used to level the screed. When installing beacons, do the following:

• Two lines are drawn from the walls to the left and right of the entrance at a distance of 30 cm - this will be the position of the outer beacons.
• The distance between these two lines is divided into equal parts so that it does not exceed 150 cm. It is desirable that one of the stripes falls directly on the entrance to the room. If necessary, the strip at the entrance can be smaller.
• Lines for the position of future lighthouses are drawn on the floor. Marks are made on them for the location of the dowels in increments of 40-50cm.
• Using a hammer drill with a drill corresponding to the dowel, holes are drilled to a given depth.

To align the dowel heads in one plane, it is best to use a laser level. If in the arsenal home handyman If you don’t have it, it doesn’t matter, now you can rent this very useful tool, especially since you will only need it for one day.

Laser level— an indispensable assistant when marking and installing beacons

The position of the beacons is marked on the wall. To do this, subtract the thickness of the finishing floor covering from the finished floor level previously drawn on the wall. The laser level is aligned to this mark, and then, by screwing or unscrewing the dowels, their caps are aligned at the same level. If you use a regular building level for this operation, it will take much longer, and the error will be higher.

Next, guide profiles are placed on the caps of the dowels, and the correct installation is checked with a building level. To fix the beacons in their places, use a cement mortar of the same recipe as for floor screed (1 part cement + 3 parts sand).

The beacons are removed from the dowel caps, and then slides are made from the prepared solution slightly higher than the height of the screed. It is enough to do them every 1 meter, since the beacon will already be securely fastened to the dowel caps. Next, the profile is laid and pressed into the solution, and its excess on top is immediately removed with a spatula. Finally, the level checks the correct installation of all beacons.

At the same time, you can check the correct installation of all damper tapes separating the rooms and contours and, if necessary, strengthen their position with a solution.

water heated floor

Video: Installation of beacons for underfloor heating screed

Pouring heated floor screed

Increased demands are placed on a heated water floor screed, because in addition to the mechanical loads it carries, it also experiences temperature deformations. And usually cement-sand mortar will not work here, the concrete mixture must be modified with a plasticizer and fiber.

The plasticizer is designed to reduce the water-cement ratio, increase the mobility of the mixture and increase its strength when drying. Mobility when laying underfloor heating screed is extremely important, since the solution must tightly “grab” the pipes and release easily air bubbles out. Without using a plasticizer, the only way to increase the workability of the mixture is to add water to it. But then only part of the water will react with the cement, and the rest will evaporate for a long time, which will increase the setting and hardening time and reduce the strength of the screed. The water-cement ratio should be exactly the same as to allow the screed to set. Typically, 1 kg of cement requires 0.45-0.55 kg of water.

The plasticizer is available in liquid and dry form. It must be used exactly as the manufacturer recommends, and no other way. All sorts of “substitutes” in the form liquid soap, washing powder, PVA glue are not acceptable.

The fiber is intended for dispersed reinforcement of a concrete mixture, which allows one to significantly reduce or virtually eliminate the formation of cracks, increase strength and abrasion resistance, and increase bending and compressive strength. This is achieved by the fact that fiber microfibers are distributed and fasten the screed throughout the entire volume of the concrete mixture.

Fiber can be metal, polypropylene and basalt. To screed heated floors, it is recommended to use polypropylene or basalt fiber. It is added according to the manufacturer's recommendations, but it is recommended to use at least 500 grams of polypropylene fiber per 1 m 3 of the finished solution. To get a mixture with best properties, add 800 or more grams per 1 m 3.

On sale you can find ready-made mixtures for pouring heated floor screeds from well-known and not so well-known manufacturers. These mixtures already contain a plasticizer, fiber, and other components. Despite their undoubted ease of use and high quality, the cost of the finished screed will be significantly higher than a solution prepared independently.

Before pouring the screed, it is necessary to remove all unnecessary objects from the floor and, if necessary, vacuum the surfaces. It is also necessary to prepare all the tools and utensils for mixing and transporting the solution. All work on pouring a heated floor screed in a room must be done at one time, so it is advisable to have two assistants: one prepares the solution, the second carries it, and the main person lays and levels the screed. All windows in the room must be closed, the screed must be limited from exposure to drafts and direct sunlight.

Independent preparation of a solution for screeding a heated floor should only be carried out mechanized way– the quality of the solution must be high. A concrete mixer or a construction mixer can be used as auxiliary mechanisms. No attachments for a drill or hammer drill will work here, no matter what various “truthful” sources say.

The basis of the solution is Portland cement of a grade not lower than M400, which must be dry and with a shelf life of no more than 6 months after the date of issue. The sand must also be dry, washed and sifted. River sand will not work - it is too regular in shape. For screed, the ratio of cement to sand should be 1:3 by weight, but in practice, few people weigh sand and cement, and a universal measurement method is used - a bucket. Considering that the density construction sand is in the range of 1.3-1.8 t/m 3, and for cement during transportation 1.5-1.6 t/m 3, then you can not be afraid to measure cement and sand in buckets, since the quality of the mixture will be quite acceptable.

The water in the solution should be approximately a third of the mass of cement, that is, for 1 bag of 50 kg of cement, approximately 15 liters of water are needed. However, the use of a plasticizer reduces the water-cement ratio, so when preparing a solution with water you need to be very careful - it is better to underfill a little and then add it, rather than overfill it.

The technology for preparing the solution with a mixer and a concrete mixer is slightly different. Using a mixer, you need to mix dry cement, sand and fluffed polypropylene or basalt fiber at low speeds and then gradually add water with a plasticizer dissolved in it. In concrete mixers gravity type, which are the absolute majority, it is difficult to mix dry cement and sand (dry cement sticks to wet blades and drums), so first part of the water with a plasticizer is poured into it, and then gradually add first cement, then sand, then another portion of cement and the remaining water. Fiber is added gradually. One part with water, the other with sand. In this case, the fiber cannot be thrown into the drum of a concrete mixer in a lump, but must be divided into portions and fluffed before loading.

The time for preparing the solution in a concrete mixer is usually 3-4 minutes, and with a mixer it is a little longer - 5-7 minutes. The readiness of the solution is determined by its uniform color and consistency. If you take a lump of solution in your hands and squeeze it, no water should come out of it, but at the same time the solution should be plastic. If you place the solution in a heap on the floor, it should not spread much, but only settle a little under its own weight. If you make cuts in it with a spatula, they should not blur, but should hold their shape.

Laying the screed begins from the far corners of the room and is carried out in strips along the beacons. Only after completing one strip, the next one is laid and leveled; the process should end at the entrance to the room. During the leveling process, there is no need to immediately try to perfectly level the surface of the screed along the beacons. The main thing is that there are no dips in the screed, and small sagging and marks from the rule can be easily corrected later.

After 1-2 days (it all depends on external conditions), when you can already walk on the screed, you need to clean its surface. First, the damper tape protruding from the screed is cut with a construction knife and the damper tape protruding from the screed is removed, and then the construction rule is taken and the sharp end is pressed against the plane of the beacons. In the direction away from you, with short but energetic movements, stripping is done until the beacons are completely exposed. Then the resulting debris is removed, the screed is moistened with a spray bottle and covered with plastic wrap.

The next day, the beacons are carefully removed, the pins can be unscrewed, and the resulting grooves are rubbed with mortar or tile adhesive. The screed is moistened and covered again; it is recommended to do this daily for the first 10 days after pouring.

Balancing the contours of a warm floor. Commissioning

After the screed has fully matured, which is at least 28 days, you can begin to balance the contours of the heated floor. And manifold flow meters will help a lot in this process. That is why it is necessary to purchase a manifold with balancing valves and flow meters.

The fact is that underfloor heating loops have different lengths, accordingly they have different hydraulic resistance. It is obvious that the “lion’s share” of the coolant will always follow the path of least resistance - that is, along the shortest circuit, while others will get much less. In this case, in the longest circuit the circulation will be so sluggish that there can be no talk of any heat removal. A well-designed underfloor heating project always indicates the flow rate in each circuit and the position of the control valves, but if the underfloor heating is done on your own, then a simplified but effective method will do.

• If the pumping and mixing unit has not yet been connected, then it is being installed. The underfloor heating collector is connected to the supply and return lines.
• All circuits of the heated floor are opened completely, the supply and return ball valves of the manifolds are opened at the inlet. Automatic air vent valves must be open.
• The circulation is turned on. The maximum temperature is set on the head of the mixing unit, but the boiler does not turn on yet; the coolant must circulate at room temperature.
• The pressure in the entire heating system is brought to working pressure (1-3 bar).
• All contours of the heated floor are closed, except for the longest one. The position of the flow meter on this circuit is noted and recorded.
• The second longest circuit opens completely. If the flow rate in it is greater, then the balancing valve is tightened until the flow rate is equal to the longest one.

• Next, all circuits are opened sequentially in descending order of their length, and the flow is regulated by balancing valves.
• As a result, the flow rate in all circuits should be the same. If this is not the case, then you can adjust the adjustment on the contours without touching the longest loop.

All of the above operations are performed correctly and the flow meters show that circulation in the circuits is occurring, then you can begin testing the heated floor with heated coolant. You need to start with low temperatures - from 25°C, and then every day gradually increase the temperature by 5°C, until the coolant is supplied to the circuits at its operating temperature. What is the sequence of actions at this stage?

• The temperature on the thermostatic valve of the mixing unit is set to 25°C, the circulation pump is turned on at first speed, and the system is allowed to operate in this mode for a day. At the same time, the circulation through the flow meters is controlled and adjusted.
• After a day, the temperature rises to 30°C, and the underfloor heating system is left on again for a day. The flow and temperature of the supply and return are controlled.
• The next day the temperature rises another 5°C, to 35°C. This is much closer to the operating mode of a heated floor, so it is already worth adjusting the temperature difference between the supply and return collectors. If it is in the range of 5-10°C, then this is normal, but if it is more, then the speed of the circulation pump should be increased by one step.
• The maximum temperature to which you can raise the temperature in the heated floor supply manifold is 50°C, but it is better not to do this, but check it at operating modes - 45°C or 40°C. The temperature difference between the supply and return is checked in the same way. The pump must operate at the lowest possible speed to maintain a temperature difference of up to 10°C.

The correct adjustment of the heated floor cannot be assessed immediately, since such a heating system is very inertial. It may take several hours to feel a change in temperature. Therefore, anyone who has made a heated floor on their own should arm themselves with patience and gradually bring the system to a mode that would ensure the desired floor temperature taking into account the coating. To do this, you will need to “play around” with the settings of the balancing valves, thermal heads (if the collector is equipped with them) and the speed of the circulation pump. The main thing is that the water heated floor system, made by yourself, works.

Find out how by studying the instructions with photos in a special article on our portal.

Conclusion

Stubborn statistics show that the system of warm water floors, in addition to obvious comfort, also provides significant energy savings. The same statistics indicate that the number of successful independent implementations of such heating is growing every year. All technologies have already been developed, the market is flooded with any components for every taste, color and budget. The necessary information is always available in open sources; you can always ask experts for advice. The team of authors hopes that this article dispelled the initial fear and made it clear to readers that it is quite possible to make a water-heated floor with your own hands.

Video: How to calculate and make a water heated floor with your own hands