Filling the subfloor under the warm floor. Warm floor on the ground in a private house

Such a screed is made in private houses, garages, outbuildings, industrial and warehouse premises, in large trading floors, at bus stations, etc.

The method is considered universal, it is used on all types of soils, regardless of the location of groundwater. For pouring, concrete of grade not lower than M300 is used, if the loads on the floor are large and the physical characteristics of the soil are unsatisfactory, then the grade of concrete increases and a reinforcing mesh is necessarily used.

All indicators for the thickness and characteristics of materials are prescribed in the design and estimate documentation. If it is not there, then the calculations must be done independently, while taking into account all the factors that affect the operating conditions of the floor coverings.

1. The rough screed is located below the ground, adjacent to the strip foundation at the level of the tape expansion. Such a scheme is used if there are underground rooms under the house for storing food or other needs.
2. The rough floor screed on the ground is located approximately at ground level and is adjacent to the side inner wall of the strip foundation. The most widespread situation is used not only in housing, but also in industrial construction.
3. The rough floor screed is located above the foundation tape. It is used during the construction of buildings on waterlogged soils, in areas with flood risks, etc.

There are no universal recommendations for the location of the rough screed, it all depends on the operating conditions and architectural features of the house. The only requirement is that the position of the door frame must be planned even before the start of the rough screed, the level of the finished floor should be at the level of the threshold.

Options for arranging a rough screed on the ground

The specific option is chosen by the builders, taking into account the maximum load on the structure and the proximity of groundwater. The classic solution is compacted soil, a layer of sand and gravel of various thicknesses, polyethylene film and a rough screed with or without reinforcement.

This method is recommended in cases where groundwater is located closer than two meters to the surface. Groundwater is much lower - you can simplify the construction scheme. It is allowed to pour a rough screed directly on the ground, use only sand or gravel as backfill. In some cases, it is possible to pour a subfloor directly onto the ground without using a plastic film. For a rough floor screed, the film is used not so much for waterproofing (concrete is not afraid of moisture, on the contrary, in conditions of high humidity it increases strength indicators), but for retaining cement laitance in a mixture. Without a film, it will quickly leave the concrete, which will have a very negative effect on strength.

What factors affect the construction technology of the rough screed

If they come closer than two meters to the surface, then be sure to backfill with sand and gravel. The backfill serves to prevent moisture from being drawn in by soil capillaries. If there is a backfill, then the use of a film to retain cement laitance is required. If a rough screed is made immediately on the ground, then the film can not be laid.

Important. The location of groundwater must be determined in the spring, it is during this period that they rise the most.

If the floor structure assumes the placement of heat carriers, then the rough screed should have compensation gap between the foundation. Such structures eliminate the negative impact of thermal expansion and exclude the possibility of cracking or swelling of the rough screed.

If the planned load on the floor can exceed 200 kg / m2, then reinforcement is mandatory. Reinforcement parameters are selected individually for each case. The same approach is needed in cases where it is planned to install interior partitions on the floor. You should not rely only on the reinforcement of the finishing screed, its physical characteristics do not allow it to withstand heavy loads.

A few frequently asked questions about the rough screed

Inexperienced builders often try, in order to save money or improve performance, to replace the recommended materials for adding a rough screed with others.

1. Is it advisable to replace the crushed stone bedding with expanded clay bedding for a black screed? At first glance, it may seem that this is an original solution that allows you to simultaneously insulate the floor. Professional builders recommend using this material only for those cases where groundwater is low, and expanded clay is excluded from getting wet.
2. Can gravel be replaced with broken bricks and other construction waste? Absolutely not for several reasons. Firstly, the brick draws in water, when wet, it quickly collapses, the base of the rough screed loses its strength and stability. Secondly, waste and broken bricks have different linear dimensions, it is impossible to carefully compact them because of this.
3. Is it possible to put waterproof protection only under the rough screed and not use it anymore? No. We have already mentioned that the polyethylene film performs other tasks - it does not allow cement laitance to leave the solution. Over time, the waterproofing breaks its tightness, under the influence of uneven and point loads, it will definitely break.
4. Is it possible to do a spill instead of a rough floor screed? Quite a difficult question. First you need to define what a spill is. Pouring - a layer of liquid solution, which is poured over the bedding under the rough screed. The thickness of the pouring depends not only on the thickness of the bedding layers, but also on the quality of their compaction. If the bedding is dense, then the liquid solution will not penetrate deeper than 4–6 centimeters. As a result, the bearing performance of the base for the floor is significantly reduced. Conclusion. The decision should be made taking into account the loads on the floor.

Now that we have dealt with most of the questions on the features of the rough screed device technology, we can give step-by-step instructions for pouring it.

Instructions for the manufacture of a rough screed for the floor on the ground

Consider the most complex and time-consuming option using all layers of backfill.

Step 1. Make measurements. First, on the foundation tape, you need to designate the level of the finished floor.

To do this, use a laser or hydro level. The size is determined according to the design and technical documentation or working drawings for the object. Further down, you need to put marks on the thickness of the floor, depending on its design, the thickness of the finishing screed, rough screed, gravel and sand layer.

Step 2 Remove the soil to the estimated depth, clean the site, prepare for backfilling with sand. Tamp loose soil or carefully clean the base with a shovel.

Step 3 Pour in the sand. As a rule, the thickness of the layer varies within ten centimeters. If a large amount of sand is required, then it must be poured in stages, each layer should be rammed separately. The quality of ramming will improve significantly if the work is carried out using special mechanisms: vibrorammers or vibrocompactors. During tamping, care must be taken that the sand has a more or less even and horizontal surface.

Ramming is a very important stage in arranging a rough screed on the ground, there is no need to rush. All the pits are filled and rammed again, the tubercles are cut off.

Step 4 Pour a layer of crushed stone with a thickness of ≈ 5–10 cm, carefully compact it. Crushed stone is better to take several fractions of op sizes. A larger one is poured onto the sand, and a fine one under the rough screed. In this way, the bearing characteristics of the base are improved. Part of the engineering communications can be hidden in the layers of backfill or directly in the rough screed. There is no need to strive to install all the pipes and electrical networks there, in case of emergencies it is very difficult to get to them for repair work.

Independent production of concrete mix

You can do it yourself using a concrete mixer or order it ready from construction companies. You need to choose yourself, both options can be optimal under certain conditions. It is recommended to calculate the cost of materials in both cases, evaluate your material capabilities and physical strength, the number of workers.

Concrete mixture should be below average in density. Such indicators allow concrete to independently spill over the floor area. One of the advantages of using liquid concrete is the absence of the need to install beacons and perform time-consuming work on its alignment with manual rules.

Workers only need to slightly correct the level in the places where the material is poured. If reinforcement is required, then a mesh is placed at the same time. Building regulations require that it be installed in such a way that the thickness of concrete on all sides exceeds five centimeters. Otherwise, the structure will not work as a whole, the actual strength of reinforced concrete will be much less than the calculated one. The consequences can be the saddest.

What will be the final floor chooses the developer. Regardless of the option chosen, builders recommend making reliable waterproofing on top and laying insulation. On top of these structures, a finishing screed is made under the tiled floor or wooden logs are laid under other options for finishing floor coverings. Such schemes make the floors warm, which is very important given the current prices for heat transfer fluids. At the same time, the implementation of the recommendations of professional builders significantly increases the operating time of floor coverings.

Is it profitable to make a rough concrete screed on the ground

The issue worries all developers without exception, it should be considered more carefully. We will compare with the use case for these purposes factory reinforced concrete slabs.

Installation of slabs with a truck crane

The simplest calculations, taking into account the cost of slabs and additional work and materials and rough screeds on the ground, show savings of up to 25%. And this is only the most approximate calculations. Payment for expensive loading / unloading equipment, delivery shoulder, etc. were not taken into account.

Video - Rough floor screed on the ground

In recent years, many people are leaving the noisy metropolitan areas, building private houses outside the city. Houses built from natural materials are especially popular. After the concrete walls of the apartment, life in a wooden house seems like a paradise. Due to the availability of materials, the construction of such houses is much cheaper, and the healthy microclimate created by natural material makes it easier to breathe.

But what if the wooden house has already been built, and instead of the usual concrete base, there is a dirt floor under your feet? In this case, it is advisable to install underfloor heating, laid in a concrete screed, and powered by a boiler. And as a finishing coating in a wooden house, use a laminate or porcelain stoneware tiles, since these materials are the best conductors of heat. In this way, it will be possible to make your home warm and cozy, as close as possible to the comfort of a city apartment.

Features of a warm floor on the ground

In a wooden private house, alternative heating systems are increasingly being used, which include underfloor heating, laid under the laminate.

Moreover, it is water systems that are most popular, allowing significant savings on energy consumption.

Having equipped a dry warm water floor under a laminate on the ground in a wooden private house, you can significantly reduce the cost of building a foundation, and put the house into operation faster, ensuring a high level of comfort.

It is very important that such heating has a high degree of durability. Therefore, the only way to install it is to install the pipes of the system in a concrete screed.

Despite the apparent complexity of the work on the organization of such heating, it is quite possible to organize it independently, carrying out work in several stages.

When arranging heating on the ground in the house, it is necessary to achieve the following results:

Underfloor heating cake on the ground

To comply with all the necessary requirements and ensure the rational use of the “warm water floor” system in a house powered by a boiler, a special multi-layer structure laid under the laminate helps. So what layers does the pie of the system, equipped on the ground, and working from a common heating boiler, consist of?

Before proceeding to direct work in the house, related to laying layers on the dirt floor, it is necessary to draw a control line on the wall surfaces around the entire perimeter of the room in a log house. This stage is necessary in order to adjust each layer of the cake.

Only after that you can proceed to the next stages of work, which ultimately allows you to get a dry and warm floor.

Underfloor heating cake on the ground

Laying an insulating pad

The organization of heating in the form of a water heated floor on the ground, powered by a boiler, requires preliminary insulation - pillows. And its first layer should be dry river sand of a large fraction.

It is poured onto the waterproofing covering the soil floor with a layer equal to 15 cm, after which it is carefully compacted in a wet way. If the sand is not compacted, then in the future the soil may subside.

If groundwater is located close, then first the earthen floors must be provided with a drainage system.

The next step will be laying a pillow of large gravel or expanded clay. Moreover, it is preferable to use crushed stone, since it has a very low degree of thermal conductivity, which means it will more effectively retain heat inside the cake.

It should be borne in mind that the thickness of the pillow for the “warm floor” system, together with sand, should not exceed 30 cm.

Pouring a rough screed

To increase the strength of the structure, before proceeding with the pouring of the rough screed, it is necessary to lay a reinforcing mesh. Also, when installing water floor heating in a wooden house, it is necessary to be guided by the general requirements for the length of the pipeline in the circuit: it should not exceed 100 m. Therefore, if the area of ​​\u200b\u200bthe room is large, the floor must be divided into sections, laying a damper tape around their perimeter.

The thickness of the rough screed should be 10-15 cm. It is possible to eliminate cracking of the rough screed when arranging heating on the ground under the laminate if you wet it daily with water, covering it with plastic wrap in this form. Such manipulations must be carried out within a week.

Laying waterproofing

To obtain a dry warm floor, a waterproofing layer is laid on its rough surface, which can be an ordinary polyethylene film with a thickness of 250 microns or more. However, PVC membranes will handle this function more effectively. It should be noted that along the perimeter of the entire room it is necessary to make an allowance for the walls equal to 15 cm, fixing it with construction tape. They also glue all the joints of the film. Excess waterproofing is removed after all work is completed.

Laying thermal insulation

To get a dry and warm floor in a private house allows laying a heat-insulating layer. This minimizes heat loss. Styrofoam or extruded polystyrene plates with a thickness of 5 cm to 10 cm can be laid as thermal insulation. The latter option is preferable.

Insulation of the base before laying pipes

Laying water circuits and finishing screed

It is necessary to lay a reinforcing mesh on the heat-insulating layer, which in this case will perform two functions:

The contours of the warm floor on the ground, laid under the laminate, can consist of various pipes. But the most popular are pipes made of metal-plastic and cross-linked polyethylene. Underfloor heating circuits are laid with a snake or snail, observing a certain step between the turns of the system.

Regardless of the method of laying the circuits and their number, they are all connected to a collector, which is installed on the wall in close proximity to the floor. Next, the system is pressure tested and tested for thermal stability.

For the preparation of a cement-sand mixture, cement grade M100 is used. And the mixture itself is prepared by mixing with sand in proportions of 1: 3. The drying time of the finished floor is about 28 days, after which it will be possible to lay the laminate. You can reduce the waiting time if you use the dry method of laying the mixture.

When installing several water circuits laid under the laminate, it is necessary to use expansion joints created by separating sections of the room with a damper tape.

How to install a heating boiler

The most important stage in the organization of heating in a private house is the installation of a boiler of a certain power, which should be determined based on the total power of all circuits of a warm water floor and a margin equal to 15-20%.

The circulation of the coolant in the system is carried out using a pump, which can be included in the boiler package or purchased separately. If the area of ​​the house exceeds 150 m², additional pumping equipment is installed in manifold cabinets.

It should be noted that when installing several floor heating circuits, it is advisable to install two collectors - one for the supply of coolant, and the other for its intake.

At the same time, shut-off valves must be installed at each outlet from the collector, which will allow disconnecting individual circuits from the system.

To eliminate the need to drain the coolant from the system during the period of repair work, shut-off valves are installed at the inlet and outlet of the boiler.

When the "warm water floor" system under the laminate is fully assembled and connected to the collector, all that remains is to connect the collector pipes to the pipes of the heating boiler.

The piping of the heating boiler must be carried out in accordance with the drawing, and the pipelines must be connected using factory parts.

Video: Tying a wall-mounted boiler

ElenaRudenkaya (Expert Builderclub)

Good afternoon, compatriot.

I'll start answering the questions in order:

1. You can make floors on the ground. There can be no freezing inside the house. Of course, you do not indicate the parameters of the foundation and do not apply plans, but I can say that there will definitely not be freezing there. The floors are inside the building. Even in the basement under the house there will be a positive temperature. But of course the floors and basement will need to be insulated according to all the rules so that there is no heat loss. It is also necessary to make waterproofing of the floor on the ground. Do for God's sake such a floor level as you need, there are no contraindications.

2. Ideally, all these fillings should be made with sand, since it practically does not shrink if it is compacted. If the soil has already been compressed and breaks off with a crowbar, then it is enough for you to go through it with a manual rammer from above, without digging it up again. If this soil is clay, then it would be good to drive large gravel into the clay, it is to drive it in and you get an adobe base under the floor. This is a very dense base and a good preparation for the screed. Any layers of soil or bedding are usually tamped every 10 cm. Since you have already poured, now just tamp from above. And you don’t indicate how thick the layer is not rammed. Refine this moment? The ground can be filled with a large thickness, but under the screed it is better to add sand or gravel, so to speak, preparation. Again, there would be a good photograph of this backfill with soil, something could be said more precisely. But according to your words, I understand that there is most likely clay. What kind of soil was dug up at least?

Photo of manual rammer:

3. I would recommend you to make a bedding of 5-10 cm. Firstly, it will even out all the bumps and pits. Secondly, this is not bad for a concrete rough screed, it will be inconvenient for you to pour the screed on the ground and vibrate it. And if there is a small layer, then you can safely vibrate with a vibrating rail. But this layer is completely optional, it is desirable to pour sand. See for yourself. The polyethylene film is needed thick and preferably in 2 layers (Technical film polyethylene sleeve secondary LDPE (1500x120mkn x100m)). Look at prom.ua, I saw her there. You can use the old roofing material or roofing felt. It is desirable to make an overlap on the wall no more than 10 cm, there will also be an overlap from waterproofing (roofing material). When you cover it, an overlap of layers of 5 cm is also made and sealed with adhesive tape. It is not worth fixing, just pour on top, it will take as it should.

After the base of the floor is prepared for pouring the screed, you can proceed with the installation of beacons. Beacons are necessary as guides, along which the horizontal plane and the surface of the screed are aligned. If in the draft it is still somehow possible without them, then in the final one they are necessary to raise the reinforcing mesh from the bottom edge and level the floor level.

4. The rough screed consists of concrete, since it is a load-bearing part and it acts as a kind of floor slab. Therefore, the brand of concrete is enough M150. For the manufacture of M150 concrete, one part of cement, 3.5 parts of sand, and 5.7 parts of aggregate (crushed stone) are used. If you are going to prepare the mixture yourself, then you need to purchase river sand ( cement-sand screed) and crushed stone fraction 5-10 ( concrete screed), as well as cement M300 or M400.

The floor layers will be:

1. Bedding, you can not do it, although I would level it with sand.

2. The film, so that the cement milk does not leak, it partially retains the milk, but this is usually enough for concreting. They will not tear, it is dense polyethylene. Even if there are small holes, you put it in 2 layers.

3. Rough screed 7-10 cm without reinforcement made of M150 concrete. It dries and gains strength within 7 days by 70%, that is, after 7 days you can walk and carry out the next stage of work.

4. Waterproofing roofing material, preferably in 2 layers, because the crushed stone sticking out of the concrete can damage 1 layer, but 2 is enough. A waterproofing layer is laid with a wall approach of about 10 cm. A damper tape is fixed to the wall around the entire perimeter of the floor. It will compensate for the thermal expansion of the floor when heated. As a result, you can cut off excess waterproofing and damper tape. This is related to the 5th question.

5. Styrofoam or XPS 50 mm thick, strength 35 kg/cu.m. It is not fixed, only glued with tape so that it does not move. Ideally, this is of course EPS with locks, but usually it is more expensive than polystyrene. It just unfolds neatly all over the floor and then a fine screed is carefully made. You can walk on it, but also very carefully. Put a reinforcing mesh on the insulation.

6. Finishing screed with underfloor heating and mesh reinforcement (in cards or rolls) with a wire diameter of 3-6 mm, with a cell of 100x100 mm, an overlap of 100 mm during rolling. In your case, the mesh is placed directly on the floor and an intermediate thin screed is poured, the thickness of which is 2-3 cm. It is necessary that the thin screed gain the required strength. This will take two to five days (at room temperature). In this case, the damper tape does not make sense, since it does not work with thin layers of screed. We better lay it in a layer with waterproofing. By the way, it can be replaced by a laminate substrate cut into strips of 5-8 cm and glued to double-sided tape.

Ask. Maybe I missed something.

reply

The installation of a warm floor in itself is considered a complex engineering task. If the floor is in direct contact with the ground and serves as part of a liquid heating system, the likelihood of making a mistake increases significantly. Today we will talk about both the materials used and the phased device.

Laying a warm floor on the ground refers to complex engineering measures. This means that the contractor is responsible not only for the efficiency and long life of the heating system, but also for the normal behavior of the flooring under cyclic heating conditions. Therefore, act consistently and strictly follow the device technology recommendations.

Which pipes are suitable for underfloor heating

The first thing to do is to decide on the type of heat-conducting tubes. While the issue with the acquisition of the desired type of product is being resolved, you will have time to carry out all the necessary preparatory work. In addition, you will know from the outset the system for fixing the pipes, and you will provide everything necessary for this.

So, let's start with the rejection of pipes that do not have such a purpose as use in underfloor heating systems. This includes metal-plastic polyethylene pipes connected by a system of press fittings and PPR pipes for soldering plastic water pipes. The former do not perform well in terms of reliability, the latter do not conduct heat well and have high coefficients of thermal expansion.

Initially, a convenient and reliable mounting system for temporary pipe fastening is selected. It can also be a reinforcing mesh, to which the pipes will be tied with wire, but imagine installing in this way on an area of ​​​​100 m 2 or if suddenly several ties come off during the pouring of concrete. Therefore, a mounting underlay or rail system must be used. They are attached to the floor base while the pipes are not yet laid, then the pipes are fixed in the guides with clips or click-clamps.

The mounting system itself can be plastic or metal. There is not much difference in this, the only thing you need to pay attention to is how reliable the fixation is and whether the guides themselves can damage the pipes.

Finally, we decide on the material of the pipes. There are two types of products recommended for use in underfloor heating systems. For both, the mounting technology eliminates the influence of the human factor when bending and connecting.

Copper. Despite the increased cost, copper tubing is easy to install; soldering requires a bottle of flux and a gas burner. Copper performs best in systems of "fast" underfloor heating, which works in parallel with radiators, but not on a permanent basis. The bending of copper tubes is carried out according to the template, respectively, their fracture is extremely unlikely.

Polyethylene. This is a more common class of pipes. Polyethylene is practically not subject to fracture, but a special crimping tool is required for installation. Polyethylene can have different density, it is recommended not less than 70%. The presence of an internal oxygen barrier is also important: polyethylene poorly resists diffuse penetration of gases, while water in a pipe of this length can entrain significant amounts of oxygen from the external environment.

Soil preparation

When installing a warm floor on the ground, a “pie” is prepared, the thickness and filling of which are determined individually. But these data are important already at the first stage of work, in order to deepen the earthen floor if necessary and not sacrifice the height of the room.

In general, the soil is removed 30-35 cm below the level of the planned floor covering, taken as the zero point. The surface is carefully leveled in a horizontal plane, the geotextile layer is backfilled with incompressible material, in most cases, PGS is used for this.

After careful manual tamping of the bedding, preparation is carried out with low-grade concrete. For additional thermal insulation, this layer may consist of lightweight expanded clay concrete. It is important that the surface be brought out into a common plane located below the zero mark by the thickness of the cake plus about 10-15 mm more.

The choice of insulation

A floor pie with water heating consists of a heater tightly sandwiched between two layers of cement-sand screed. A fairly narrow range of requirements is imposed on the insulation itself.

Mainly compressive strength is normalized. Extruded polystyrene foam with a density of 3% or more is ideal, as well as PIR and PUR boards as more fireproof. If desired, you can use mineral wool slabs of grade 225 according to GOST 9573-96. Cotton wool is often abandoned due to the complexity of its installation and the need to cover the insulation with a hydrobarrier (polyamide film). It is characteristic that the minimum thickness of the plate is 40 mm, while when installing a reflective screen made of XPS, the thickness of the latter rarely exceeds 20-25 mm.

Foam polymer materials also serve as a good barrier to moisture migrating from the soil; they do not require a waterproofing device. Many may be put off by the questionable safety of styrene-containing material or the price of more expensive boards with complete chemical inertness (PUR and PIR).

The thickness of the insulation is determined by thermotechnical calculation. If the preparation used concrete with expanded clay as a filler, 10-15 mm XPS or 60 mm mineral wool will be sufficient. In the absence of insulated preparation, these values ​​\u200b\u200bshould be increased by 50%.

Preparatory and accumulating screeds

It is very important that the insulation is tightly clamped between two ties and that any movement or vibration of it is excluded. The concrete preparation of the floor is leveled with a preparatory screed, then insulation boards are glued onto it using tile adhesive under the comb. All joints are sealed with glue. If mineral wool is used, the concrete preparation must first be covered with a layer of penetrating waterproofing.

The screed layer above the insulation must be so thick that its total thermal conductivity is at least 3-4 times lower than that of the thermal screen. In general, the thickness of the screed is about 1.5-2 cm from the final height of the ceilings, but you can freely “play” with this value to adjust the inertia of the warm floor. The main thing is to change the thickness of the insulation accordingly.

The top layer of the screed, subjected to heating, is poured after the walls are enclosed with a damper tape. The filling of the accumulative screed can, for convenience, be carried out in two stages. On the first one, about 15-20 mm are poured with reinforcement with a rare mesh. It is convenient to move along the resulting plane and fix the pipe installation system, the remainder is poured to the zero level minus the thickness of the floor covering.

1 - compacted soil; 2 - sand and gravel bedding; 3 - preparatory reinforced screed; 4 - hydrovapor barrier; 5 - insulation; 6 - reinforcing mesh; 7 - floor heating pipes; 8 - cement-sand screed; 9 - flooring; 10 - damper tape

System installation, proportions and loop pitch

The laying of underfloor heating pipes should be carried out according to a scheme previously thought out and drawn on the floor. If the room has a shape other than rectangular, its plan is divided into several rectangles, each of which is represented by a separate loop loop.

The same principle applies to floor zoning. For example, in the play area, tubes can be laid at a more frequent pace, and it is advisable not to lay them under cabinet furniture at all. In each individual coil of a rectangular shape, depending on the priority of heating, the tubes can be laid either in a snake or a snail, or a combination of options. The general rule is simple: the farther a specific point is from the beginning of the duct, the lower its temperature, on average, there is a drop of 1.5-2.5 ºС every 10 meters, respectively, the optimal length of the loop is in the range of 50-80 meters.

The minimum distance between adjacent tubes is determined by the manufacturer according to the allowable bending radius. A denser gasket is possible according to the “snail” scheme or with the formation of wide loops at the edges of the snake. It is optimal to adhere to a distance equal to 20-30 values ​​of the tube diameter. You also need to make allowances for the thickness of the storage screed and the desired floor heating rate.

The mounting system is fastened along the route of laying through the insulation to the concrete preparation layer, respectively, the length of the fasteners (usually plastic BM dowels) should be 50% more than the distance to the surface of the preparatory screed.

When laying the pipe, you should consider an improvised spool for unwinding, otherwise the pipe will constantly twist and break. When all the hinges are fixed in the installation system, they are tested with high pressure and, if the test results are satisfactory, the top layer of the storage screed is poured.

Inclusion of a warm floor in the heating system

It is recommended to lay whole pipe sections without joints in the screed layer. The tails of the loops can be reduced either to local collectors, or lead directly to the boiler room. The latter option is usually convenient when the heated floor is a little far from the boiler or if all rooms have a common corridor, which needs indirect heating.

The ends of the pipes are rolled with an expander and connected by crimping or soldering with threaded fittings for connection to a manifold assembly. Each of the outlets is equipped with shut-off valves, ball valves with a red flywheel are installed on the supply pipes, and with a blue one on the return. A threaded transition with shutoff valves is necessary for emergency shutdown of a separate loop, its purging or flushing.

An example of a scheme for connecting a water heated floor to a heating system: 1 - a heating boiler; 2 - expansion tank; 3 - security group; 4 - collector; 5 - circulation pump; 6 - manifold cabinet for heating radiators; 7 - manifold cabinet of underfloor heating

The collectors are connected to the heating main by analogy with heating radiators, two-pipe and combined switching schemes are possible. In addition to the thermostat, the collector units can be equipped with recirculation systems that maintain a comfortable temperature of the coolant in the supply at about 35-40 ºС.

One of the most important aspects of repair and construction is the arrangement of floors. In a private house, this problem is more acute. Quite often they design a warm floor on the ground - a popular, popular solution to the issue. After all, it keeps heat well, creates comfort, sometimes replaces heating. To equip such a coating, it is necessary to strictly comply with the conditions of SNiP, installation rules, which is associated with soil shrinkage.

Laying the "warm floor" system

Warm floor on the ground - what is it?

Underfloor heating is like a multi-layer cake, which necessarily contains thermal insulation. The floor structure on the ground is done in two stages: a rough screed is poured in the lower layers, and after it has matured, the remaining layers are laid.

The point is in the soil - it has the properties of subsidence. Even when it is caked, compacted, after laying the "pie" of the warm floor, movements occur, and the floor elements may break. Therefore, first, according to the rules, a rough screed is made, then a warm floor is laid.

Scheme of a heated floor pie on sand

Sometimes a heated structure is made without the first screed - a warm floor is laid on the sand. This can be done if you install two reinforcing frames: one under the heat insulator, the other in the screed - you need to carefully compact the layers of sand, gravel, soil.

The installation of a heated floor in a building depends on the soil indicators, which must comply with the standards. Groundwater should be no more than 600 cm from the soil layer. It is required that the soil has low indicators of friability, airiness. Construction is prohibited on chernozem soils, sandstones.

It is important to take into account the load that acts on the foundation. Floor installation provides the following:

1. Thermal insulation.
2. Ground water flood protection.
3. Elimination of external sounds.
4. Protection against ingress of water vapor into the floor.
5. Prevention of cracking.
6. Providing comfort to residents.

The composition of the floor system pie

For rooms, premises with an area of ​​20 sq. m use an electric, water method of floor heating. For small rooms (bathrooms) electric heating is more suitable.

Attention! When arranging and choosing the type of underfloor heating, it should be remembered that water heating requires a boiler, a collector, and much more. To connect a floor heating system to a central heating system, special permits are required, since installation in an existing system may lead to its incorrect operation.

The structure of the "pie" of the floor on the ground

By design, a warm floor on the ground consists of several layers, the installation of each is carried out in stages. Despite several methods of laying the structure, there are general rules that are followed in any case:

• Before laying the first layer of the pie, it is required to prepare the soil: clean it of debris, various objects, grass cover, level the surface.
• Well-compacted sand - 15 cm. A vibrating plate is used to compact the soil. Sand is compacted in a wet way.
• A layer of crushed stone (gravel) 8-15 cm. It does not allow groundwater to rise. Metal mesh that strengthens the screed. Rough concrete screed - 150 mm - with compensation distance between zones. In between there is a damper tape.
• Waterproofing layer to prevent moisture absorption by concrete. It is made from a film, a membrane. The material is overlapped, secured with tape. Bitumen-rubber mastic is also suitable.
• Insulation layer. To do this, use foamed polystyrene foam, foil polystyrene. Plates are used for high loads. The thickness depends on the climate conditions in the region.
• Waterproofing from a film, roofing material is carried out in 1-2 layers.
• Installation of floor pipes, finishing screed with a total thickness of 10 cm with mandatory reinforcement. A water circuit is attached to the grid.
• Decorative flooring.

The whole process of arranging the layers of the cake according to the technology can take up to 1.5 months.

Advantages, disadvantages of a heated floor

The floor heating system has its advantages:

1. Reliably protects from cold. After all, the soil under the floor has a positive temperature.
2. Choose any heater.
3. Film, roofing material is suitable for waterproofing.
4. The floor is finished with any coating.
5. When arranging, the entire load is directed to the ground, so calculations are not required. If the load is increased, the thickness of the cake increases.
6. Changes can be made to the design, for example, to make the thermal insulation thicker.
7. The warm floor is used as the main, additional, heating. Such floors warm up quickly, distribute the temperature evenly, which eliminates the occurrence of drafts.
8. The floors are well soundproofed.
9. Protect against the formation of mold, fungi, and other microorganisms.

Arrangement of a floor heating system during the construction of a house

Despite the large number of advantages, it should be noted and negative aspects. Such a floor reduces the height of the room, if the system breaks down, repairs will be expensive, difficult, the location of groundwater must be taken into account, the process of arranging the system on the ground takes a long time (it is advisable to carry out laying during the construction of the house).

• A warm floor on the ground in a private house can be arranged independently, having studied the entire technology of the processes. First, determine to what level the soil should be removed.

Attention! The soil must be removed - it will decompose, "smell" if it is not removed. Moreover, the top layer is very loose and will settle.

• Regardless of whether the subfloor will be laid, the soil is removed. The lower layers are dense, since there are no microorganisms there, and they experience a lot of stress.
• The thickness of the heated floor can be 20 cm or more. Therefore, the markup starts from the zero level, i.e., where the finishing floor is. Make a mark and consider how deep you should go down. It is advisable to note the thickness of each layer.
• A dense layer of soil should be carefully leveled, compacted, and checked for evenness along the level. After all, this is the basis of the following materials. Sand after careful tamping is also leveled. A layer of expanded clay, crushed stone is compacted to the state of a monolith.
• The first screed is made in two ways: crushed stone with sand is poured with a liquid cement-sand mortar, a screed up to 150 mm thick is poured. To reinforce the screed, a reinforcing mesh or metal wire is used. The floor is reliable, it can withstand heavy loads.
• The joints of the polystyrene boards are glued with adhesive tape so that the solution does not leak.

Thermal insulation for a warm floor is a key point

• Plates use above 35 kg / cu. meter. For cold regions, its thickness can be more than 10 centimeters. When the thickness of the thermal insulation layer is large, then two layers are made. Moreover, the joints of the 1st layer are covered with plates of the 2nd layer.

Heated floor pie installation options

Laying is carried out in several ways - the choice depends on the flow of groundwater, the type of heating system, loads, and other factors.

The floor pie has the main layer - a concrete subfloor (it is considered the main one). There is an option when the concrete layer changes to a sand cushion 150 mm thick. All work and the sequence of their implementation does not change. However, leveling the sand cushion is much more difficult.

depending on the heater

The variant of the cake varies from the selected insulation. For example, when choosing expanded polystyrene, laying is carried out as follows:

1. Crushed stone layer - 300 mm.
2. Concrete screed - 150 mm.
3. Waterproofing.
4. Polyurethane foam.
5. Finishing screed with steel mesh reinforcement.

When using mineral wool boards, which are considered durable, resistant to deformation, they are laid in two layers. To reduce the absorption of moisture, the plates are treated with a water-repellent solution.

With a high location of groundwater

Floor cake with drainage

When subsoil waters are close, then observance of the sequence of layers is not enough - water must be diverted. If the floor heating cake is laid on the ground below the groundwater level, then drainage must be done.

Therefore, at least 30 cm below the required level, a drainage system is made. They use river sand, other rocks, for example, excavated soil mixed with crushed stone.

Important! For the device of the drainage system, it is impossible to use peat rocks of the soil, black soil.

The selected material is poured in layers of 100 mm, which are compacted, spilled with water. Three layers are made, geotextiles are laid on the compacted material. It passes water without mixing with different materials. It has increased strength, is not damaged by insects, animals, evens out the load.

Waterproofing is carried out with bituminous mastic (other material), thermal insulation along the perimeter of the floor foundation with expanded polystyrene plates. For reliability, they make the main screed, carry out waterproofing with membranes. Then the remaining layers are laid: heat insulator, fasteners, pipes. It is poured with a screed, the front cover is laid.

The warm floor of a private house is a great option that saves time and reduces costs. Competent arrangement of the "pie" of the heated floor provides warmth, home comfort for a long time.

Multilayer "pie" of the "warm floor" system on the sand: