Installing a heated floor in itself is considered a complex engineering task. If the floor is in direct contact with the ground and serves as part fluid system heating, the likelihood of making a mistake increases significantly. Today we will talk about both the materials used and the step-by-step design.
Laying heated floors on the ground is a complex engineering undertaking. This means that the contractor is responsible not only for the efficiency and long service life of the heating system, but also for the normal behavior of the floor covering under cyclic heating conditions. Therefore, act consistently and strictly follow the recommendations for device technology.
Which pipes are suitable for heated floors?
The first thing you need to do is decide on the type of heat-conducting tubes. While the issue of acquisition is being resolved the right type products, you will have time to carry out all the necessary preparatory work. In addition, you will know the pipe fastening system from the very beginning, and you will provide everything necessary for this.
So, let's start by refusing pipes that do not have such a purpose as being used in underfloor heating systems. This includes metal-plastic polyethylene pipes connected by a system of press fittings and PPR pipes for soldering plastic water pipe. The former do not perform well in terms of reliability, the latter conduct heat poorly and have high coefficients of thermal expansion.
Initially, a convenient and reliable installation system for temporary pipe fastening is selected. It could be reinforcement mesh, to which the pipes will be tied with wire, but imagine installation in this way over an area of 100 m2 or more, or if suddenly several ties come off during the process of pouring concrete. Therefore, a mounting base or rail system should be used. They are attached to the base of the floor while the pipes are not yet laid, then the pipes are fixed in the guides with clips or click clamps.
The fastening 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 pipe material. There are two types of products recommended for use in underfloor heating systems. For both, the installation technology eliminates the influence of the human factor when bending and connecting.
Copper. Despite the increased cost, copper tubes are easy to install; for soldering you will need a bottle of flux and gas-burner. Copper the best way manifests itself in “fast” underfloor heating systems, which operate in parallel with radiators, but not on an ongoing basis. Bend copper tubes are carried out according to a template; therefore, their fracture is extremely unlikely.
Polyethylene. This is a more common class of pipes. Polyethylene is practically unbreakable, but installation will require a special crimping tool. Polyethylene can have different densities, but not lower than 70% is recommended. The presence of an internal oxygen barrier is also important: polyethylene poorly resists the diffuse penetration of gases, at the same time, water in a pipe of such length can entrain significant volumes of oxygen from the external environment.
Soil preparation
When installing a heated floor on the ground, a “pie” is prepared, the thickness and filling of which are determined individually. But this data is important already at the first stage of work, so that, if necessary, the earthen floor is deepened and not sacrificing 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 the horizontal plane, the layer of geotextile is backfilled with incompressible material, in most cases ASG is used for this.
After careful manual compaction of the backfill, 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 is displayed in common plane, located below the zero mark by the thickness of the pie plus about 10-15 mm.
Choice of insulation
A water-heated floor pie consists of insulation tightly sandwiched between two layers of cement-sand screed. The insulation itself is subject to a fairly narrow range of requirements.
Compressive strength is mainly standardized. 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 typical that the minimum thickness of the slab is 40 mm, while when constructing a reflective screen made of EPS, 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 waterproofing. Many may be stopped 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 thermotechnical calculation. If concrete with expanded clay as a filler was used in the preparation, 10-15 mm of EPS or 60 mm of mineral wool will be sufficient. In the absence of insulated preparation, these values should be increased by 50%.
Preparatory and accumulating screeds
It is very important that the insulation is tightly clamped between two ties and any movement or vibration 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 used mineral wool, the concrete preparation must first be coated with a layer of penetrating waterproofing.
The screed layer above the insulation must be of such a thickness that its overall thermal conductivity is at least 3-4 times lower than that of heat shield. In general, the thickness of the screed is about 1.5-2 cm from the final height of the ceilings, but to adjust the inertia of the heated floor, you can freely “play” with this value. The main thing is to change the thickness of the insulation accordingly.
The top layer of the screed, subject to heating, is poured after fencing the walls with damper tape. For convenience, pouring the accumulating screed can be carried out in two stages. On the first one, about 15-20 mm is poured with reinforcement with a sparse mesh. It is convenient to move along the resulting surface and attach the pipe installation system; the remainder is poured to the level of the zero mark, minus the thickness of the floor covering.
1 - compacted soil; 2 - sand and gravel backfill; 3 - preparatory reinforced screed; 4 - water vapor barrier; 5 - insulation; 6 — reinforcing mesh; 7 - underfloor heating pipes; 8 - cement-sand screed; 9 — flooring; 10 - damper tape
System installation, proportions and loop pitch
Laying of underfloor heating pipes should be carried out according to a pre-designed diagram 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 turn of the loop.
The same principle applies when zoning the floor. For example, in play area the tubes can be laid in more frequent increments, and it is advisable not to lay them under cabinet furniture at all. In every single turn rectangular shape, depending on the heating priority, the tubes can be laid either as a snake or a snail, or a combination of options. General rule simple: the further a specific point is from the beginning of the flow, 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 permissible bending radius. A denser laying is possible using a “snail” pattern or with the formation of wide loops at the edges of the snake. It is optimal to maintain a distance equal to 20-30 times the diameter of the tube. You also need to make adjustments for the thickness of the accumulating screed and the desired rate of heating of the floor.
The installation system is attached along the route of laying through the insulation to the layer concrete preparation Accordingly, the length of the fasteners (usually plastic BM dowels) should be 50% greater than the distance to the surface of the preparatory screed.
When laying the pipe, you should create an improvised spool for unwinding, otherwise the pipe will constantly twist and break. When all the loops are secured in installation system, they are being checked high pressure and, if the test results are satisfactory, it is poured upper layer accumulating screed.
Including heated floors in the heating system
It is recommended to lay whole sections of pipe without joints in the screed layer. The tails of the loops can be led either to local collectors or led directly to the boiler room. The latter option is usually convenient when the heated floor is a short distance from the boiler or if all rooms have a common corridor, which requires indirect heating.
The ends of the pipes are rolled with an expander and connected by crimping or soldering with threaded fittings for connection to the collector unit. 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 flywheel on the return pipes. A threaded transition with shut-off valves is necessary for emergency shutdown of a separate loop, its purging or flushing.
An example of a diagram for connecting a water heated floor to a heating system: 1 - heating boiler; 2 — expansion tank; 3 - security group; 4 - collector; 5 - circulation pump; 6 - manifold cabinet for heating radiators; 7 - manifold cabinet for underfloor heating
The connection of collectors to the heating main is carried out by analogy with heating radiators; two-pipe and combined connection schemes are possible. In addition to the thermostat, collector units can be equipped with recirculation systems that support comfortable temperature The coolant in the supply is about 35-40 ºС.
Installing a heated 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 step-by-step design.
Laying heated floors on the ground is a complex engineering undertaking. This means that the contractor is responsible not only for the efficiency and long service life of the heating system, but also for the normal behavior of the floor covering under cyclic heating conditions. Therefore, act consistently and strictly follow the recommendations for device technology.
Which pipes are suitable for heated floors?
The first thing you need to do is decide on the type of heat-conducting tubes. While the issue of purchasing the right type of product is being resolved, you will have time to carry out all the necessary preparatory work. In addition, you will know the pipe fastening system from the very beginning, and you will provide everything necessary for this.
So, let's start by refusing pipes that do not have such a purpose as being used 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 conduct heat poorly and have high coefficients of thermal expansion.
Initially, a convenient and reliable installation system for temporary pipe fastening is selected. This could also be a reinforcing mesh to which the pipes are tied with wire, but imagine installing it in this way over an area of 100 m2 or more, or if suddenly several ties come off during the process of pouring concrete. Therefore, a mounting base or rail system should be used. They are attached to the base of the floor while the pipes are not yet laid, then the pipes are fixed in the guides with clips or click clamps.
The fastening 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 pipe material. There are two types of products recommended for use in underfloor heating systems. For both, the installation technology eliminates the influence of the human factor when bending and connecting.
Copper. Despite the increased cost, copper tubes are easy to install; for soldering you will need a bottle of flux and a gas torch. Copper works best in “fast” underfloor heating systems, which operate in parallel with radiators, but not on an ongoing basis. The bending of copper tubes is carried out according to a template; therefore, their fracture is extremely unlikely.
Polyethylene. This is a more common class of pipes. Polyethylene is practically unbreakable, but installation will require a special crimping tool. Polyethylene can have different densities, but not lower than 70% is recommended. The presence of an internal oxygen barrier is also important: polyethylene poorly resists the diffuse penetration of gases, at the same time, water in a pipe of such length can entrain significant volumes of oxygen from the external environment.
Soil preparation
When installing a heated floor on the ground, a “pie” is prepared, the thickness and filling of which are determined individually. But this data is important already at the first stage of work, so that, if necessary, the earthen floor is deepened and not sacrificing 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 the horizontal plane, the layer of geotextile is backfilled with incompressible material, in most cases ASG is used for this.
After careful manual compaction of the backfill, 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 is brought into a common plane located below the zero mark by the thickness of the pie plus about another 10-15 mm.
Choice of insulation
A water-heated floor pie consists of insulation tightly sandwiched between two layers of cement-sand screed. The insulation itself is subject to a fairly narrow range of requirements.
Compressive strength is mainly standardized. 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 typical that the minimum thickness of the slab is 40 mm, while when constructing a reflective screen made of EPS, 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 waterproofing. Many may be stopped 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 thermal engineering calculations. If concrete with expanded clay as a filler was used in the preparation, 10-15 mm of EPS or 60 mm of mineral wool will be sufficient. In the absence of insulated preparation, these values should be increased by 50%.
Preparatory and accumulating screeds
It is very important that the insulation is tightly clamped between two ties and any movement or vibration 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 coated with a layer of penetrating waterproofing.
The screed layer above the insulation must be of such a thickness that its overall thermal conductivity is at least 3-4 times lower than that of the heat shield. In general, the thickness of the screed is about 1.5-2 cm from the final height of the ceilings, but to adjust the inertia of the heated floor, you can freely “play” with this value. The main thing is to change the thickness of the insulation accordingly.
The top layer of the screed, subject to heating, is poured after fencing the walls with damper tape. For convenience, pouring the accumulating screed can be carried out in two stages. On the first one, about 15-20 mm is poured with reinforcement with a sparse mesh. It is convenient to move along the resulting surface and attach the pipe installation system; the remainder is poured to the level of the zero mark, minus the thickness of the floor covering.
1 - compacted soil; 2 - sand and gravel backfill; 3 - preparatory reinforced screed; 4 - water vapor barrier; 5 - insulation; 6 — reinforcing mesh; 7 - underfloor heating pipes; 8 - cement-sand screed; 9 - floor covering; 10 - damper tape
System installation, proportions and loop pitch
Laying of underfloor heating pipes should be carried out according to a pre-designed diagram 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 turn of the loop.
The same principle applies when zoning the floor. For example, in the play area, pipes can be laid in more frequent steps, but it is advisable not to lay them under cabinet furniture at all. In each individual rectangular coil, depending on the heating priority, the tubes can be laid either as a snake, or a snail, or a combination of options. The general rule is simple: the further a specific point is from the beginning of the flow, 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 permissible bending radius. A denser laying is possible using a “snail” pattern or with the formation of wide loops at the edges of the snake. It is optimal to maintain a distance equal to 20-30 times the diameter of the tube. You also need to make adjustments for the thickness of the accumulating screed and the desired rate of heating of the floor.
The installation system is attached along the route of laying through the insulation to the concrete preparation layer; accordingly, the length of the fasteners (usually plastic BM dowels) should be 50% greater than the distance to the surface of the preparatory screed.
When laying the pipe, you should create an improvised spool for unwinding, otherwise the pipe will constantly twist and break. When all hinges are secured in the installation system, they are tested with high pressure and, if the test results are satisfactory, the top layer of accumulative screed is poured.
Including heated floors in the heating system
It is recommended to lay whole sections of pipe without joints in the screed layer. The tails of the loops can be led either to local collectors or led directly to the boiler room. The latter option is usually convenient when the heated floor is a short distance from the boiler or if all rooms have a common corridor, which requires indirect heating.
The ends of the pipes are rolled with an expander and connected by crimping or soldering with threaded fittings for connection to the 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 flywheel on the return pipes. A threaded transition with shut-off valves is necessary for emergency shutdown of a separate loop, its purging or flushing.
An example of a diagram for connecting a water heated floor to a heating system: 1 - heating boiler; 2 - expansion tank; 3 - security group; 4 - collector; 5 - circulation pump; 6 - manifold cabinet for heating radiators; 7 - manifold cabinet for underfloor heating
The connection of collectors to the heating main is carried out by analogy with heating radiators; two-pipe and combined connection schemes are possible. In addition to the thermostat, collector units can be equipped with recirculation systems that maintain a comfortable temperature of the coolant in the supply at about 35-40 ºС.
IN last years Many people are leaving noisy cities and building private homes outside the city. Particularly popular are houses built from natural materials. After concrete walls apartment life in wooden house seems like paradise. Due to the availability of materials, the construction of such houses is much cheaper, and the healthy microclimate created natural material, allows you to breathe easier.
But what to do if a wooden house has already been built, and under your feet instead of the usual concrete base- dirt floor? In this case, it is advisable to install heated floors laid in concrete screed, and working from the boiler. And as a finishing coating in a wooden house, use laminate or porcelain tiles, since these materials conduct heat best. In this way, you can make your home warm and cozy, bringing it as close as possible to the comfort of a city apartment.
Features of underfloor heating
In a wooden private house, alternative heating systems are increasingly being used, which include heated floors laid under laminate.
Moreover, water systems are the most popular, allowing significant savings on energy consumption.
By installing 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 high level comfort.
It is very important that such heating has a high degree of strength. Therefore, the only way to install it is to install the system pipes in a concrete screed.
Despite the apparent complexity of the work on organizing such heating, it is quite possible to organize it independently, carrying out the work in several stages.
When arranging ground heating in a house, it is necessary to achieve the following results:
Heated floor pie on the ground
Comply with everything necessary requirements and provide rational use The “warm water floor” system in the house, powered by a boiler, is helped by a special multi-layer structure laid under the laminate. So what layers does the pie of a system built on the ground and operating from a common heating boiler consist of?
Before moving on to direct work in the house related to laying layers on the ground floor, it is necessary to log house draw a control line. This stage is necessary in order to adjust each layer of the cake.
Only after this can you move on to the next stages of work, which will ultimately allow you to get a dry and warm floor.
Heated floor pie on the ground
Laying a thermal insulation cushion
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 coarse fraction.
It is poured onto the waterproofing covering the ground floor in a layer equal to 15 cm, after which it is carefully compacted using a wet method. If the sand is not compacted, the soil may sag in the future.
If groundwater is located close, then first the earthen floors must be equipped with a drainage system.
The next step will be laying a cushion of coarse crushed stone 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 taken into account that the thickness of the cushion for the “warm floor” system together with sand should not exceed 30 cm.
Pouring rough screed
To increase the strength of the structure, before starting to pour the rough screed, it is necessary to lay a reinforcing mesh. Also when installing a water underfloor heating in a wooden house you must be guided general requirements to the length of the pipeline in the circuit: it should not exceed 100 m. Therefore, if the room area is large, the floor must be divided into sections, laying a damper tape along their perimeter.
The thickness of the rough screed should be 10-15 cm. You can prevent cracking of the rough screed when installing heating on the ground under the laminate if you moisten it daily with water and cover it with plastic film. Such manipulations must be carried out within a week.
Laying waterproofing
To obtain a dry heated floor, a waterproofing layer is laid on its rough surface, which can be an ordinary polyethylene film with a thickness of 250 microns. However, PVC membranes will cope with this function more effectively. It should be noted that along the perimeter of the entire room it is necessary to make an allowance on the walls of 15 cm, securing it with construction tape. All joints of the film are also glued with it. Excess waterproofing is removed after all work is completed.
Laying thermal insulation
Laying a thermal insulation layer allows you to get a dry and warm floor in a private house. This minimizes heat loss. Foam plastic or slabs of extruded polystyrene with a thickness of 5 cm to 10 cm can be laid as thermal insulation. Moreover, 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 a heated 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 in a snake or snail pattern, 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 manifold, which is installed on the wall in close proximity to the floor. Next, the system is pressure tested and checked for thermal stability.
To prepare the cement-sand mixture, cement grade M100 is used. And the mixture itself is prepared by mixing with sand in proportions 1:3. The drying time of the finished floor is about 28 days, after which the laminate can be laid. 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 dividing sections of the room with damper tape.
How to install a heating boiler
The most important stage in organizing 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 heated water floor circuits and a reserve of 15-20%.
The coolant circulates in the system using a pump, which can be included with the boiler or purchased separately. If the area of the house exceeds 150 m², additional pumping equipment is installed in the manifold cabinets.
It should be noted that when installing several floor heating circuits, it is advisable to install two collectors - one for the coolant supply, and the other for its intake.
In this case, shut-off valves must be installed at each outlet from the collector, which will allow individual circuits to be disconnected 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 boiler inlet and outlet.
When the “warm water floor” system under the laminate is fully installed and connected to the collector, all that remains is to connect the collector pipes to the heating boiler pipes.
The heating boiler piping must be done in accordance with the drawing, and the pipelines must be connected using factory parts.
Video: Wiring a wall-mounted boiler
Installing a heated 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 step-by-step design.
Laying heated floors on the ground is a complex engineering undertaking. This means that the contractor is responsible not only for the efficiency and long service life of the heating system, but also for the normal behavior of the floor covering under cyclic heating conditions. Therefore, act consistently and strictly follow the recommendations for device technology.
Which pipes are suitable for heated floors?
The first thing you need to do is decide on the type of heat-conducting tubes. While the issue of purchasing the right type of product is being resolved, you will have time to carry out all the necessary preparatory work. In addition, you will know the pipe fastening system from the very beginning, and you will provide everything necessary for this.
So, let's start by refusing pipes that do not have such a purpose as being used 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 conduct heat poorly and have high coefficients of thermal expansion.
Initially, a convenient and reliable installation system for temporary pipe fastening is selected. This could also be a reinforcing mesh to which the pipes are tied with wire, but imagine installing it in this way over an area of 100 m2 or more, or if suddenly several ties come off during the process of pouring concrete. Therefore, a mounting base or rail system should be used. They are attached to the base of the floor while the pipes are not yet laid, then the pipes are fixed in the guides with clips or click clamps.
The fastening 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 pipe material. There are two types of products recommended for use in underfloor heating systems. For both, the installation technology eliminates the influence of the human factor when bending and connecting.
Copper. Despite the increased cost, copper tubes are easy to install; for soldering you will need a bottle of flux and a gas torch. Copper works best in “fast” underfloor heating systems, which operate in parallel with radiators, but not on an ongoing basis. The bending of copper tubes is carried out according to a template; therefore, their fracture is extremely unlikely.
Polyethylene. This is a more common class of pipes. Polyethylene is practically unbreakable, but installation will require a special crimping tool. Polyethylene can have different densities, but not lower than 70% is recommended. The presence of an internal oxygen barrier is also important: polyethylene poorly resists the diffuse penetration of gases, at the same time, water in a pipe of such length can entrain significant volumes of oxygen from the external environment.
Soil preparation
When installing a heated floor on the ground, a “pie” is prepared, the thickness and filling of which are determined individually. But this data is important already at the first stage of work, so that, if necessary, the earthen floor is deepened and not sacrificing 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 the horizontal plane, the layer of geotextile is backfilled with incompressible material, in most cases ASG is used for this.
After careful manual compaction of the backfill, 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 is brought into a common plane located below the zero mark by the thickness of the pie plus about another 10–15 mm.
Choice of insulation
A water-heated floor pie consists of insulation tightly sandwiched between two layers of cement-sand screed. The insulation itself is subject to a fairly narrow range of requirements.
Compressive strength is mainly standardized. 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 typical that the minimum thickness of the slab is 40 mm, while when constructing a reflective screen made of EPS, 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 waterproofing. Many may be stopped 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 thermal engineering calculations. If concrete with expanded clay as a filler was used in the preparation, 10–15 mm of EPS or 60 mm of mineral wool will be sufficient. In the absence of insulated preparation, these values should be increased by 50%.
Preparatory and accumulating screeds
It is very important that the insulation is tightly clamped between two ties and any movement or vibration 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 coated with a layer of penetrating waterproofing.
The screed layer above the insulation must be of such a thickness that its overall thermal conductivity is at least 3–4 times lower than that of the heat shield. In general, the thickness of the screed is about 1.5–2 cm from the final ceiling height, but to adjust the inertia of the heated floor, you can freely “play” with this value. The main thing is to change the thickness of the insulation accordingly.
The top layer of the screed, subject to heating, is poured after fencing the walls with damper tape. For convenience, pouring the accumulating screed can be carried out in two stages. At the first stage, about 15–20 mm is poured with reinforcement with a sparse mesh. It is convenient to move along the resulting surface and attach the pipe installation system; the remainder is poured to the level of the zero mark, minus the thickness of the floor covering.
1 - compacted soil; 2 - sand and gravel backfill; 3 - preparatory reinforced screed; 4 - water vapor barrier; 5 - insulation; 6 - reinforcing mesh; 7 - underfloor heating pipes; 8 - cement-sand screed; 9 - floor covering; 10 - damper tape
System installation, proportions and loop pitch
Laying of underfloor heating pipes should be carried out according to a pre-designed diagram 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 turn of the loop.
The same principle applies when zoning the floor. For example, in the play area, pipes can be laid in more frequent steps, but it is advisable not to lay them under cabinet furniture at all. In each individual rectangular coil, depending on the heating priority, the tubes can be laid either as a snake, or a snail, or a combination of options. The general rule is simple: the further a specific point is from the beginning of the flow, 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 permissible bending radius. A denser laying is possible using a “snail” pattern or with the formation of wide loops at the edges of the snake. It is optimal to maintain a distance equal to 20–30 times the diameter of the tube. You also need to make adjustments for the thickness of the accumulating screed and the desired rate of heating of the floor.
The installation system is attached along the route of laying through the insulation to the concrete preparation layer; accordingly, the length of the fasteners (usually plastic BM dowels) should be 50% greater than the distance to the surface of the preparatory screed.
When laying the pipe, you should create an improvised spool for unwinding, otherwise the pipe will constantly twist and break. When all hinges are secured in the installation system, they are tested with high pressure and, if the test results are satisfactory, the top layer of accumulative screed is poured.
Including heated floors in the heating system
It is recommended to lay whole sections of pipe without joints in the screed layer. The tails of the loops can be led either to local collectors or led directly to the boiler room. The latter option is usually convenient when the heated floor is a short distance from the boiler or if all rooms have a common corridor, which requires indirect heating.
The ends of the pipes are rolled with an expander and connected by crimping or soldering with threaded fittings for connection to the manifold assembly. Each of the branches is equipped with shut-off valves; ball valves with a red flywheel are installed on the supply pipes, and with a blue flywheel on the return pipes. A threaded transition with shut-off valves is necessary for emergency shutdown of a separate loop, its purging or flushing.
An example of a diagram for connecting a water heated floor to a heating system: 1 - heating boiler; 2 - expansion tank; 3 - security group; 4 - collector; 5 - circulation pump; 6 - manifold cabinet for heating radiators; 7 - manifold cabinet for underfloor heating
The connection of collectors to the heating main is carried out by analogy with heating radiators; two-pipe and combined connection schemes are possible. In addition to the thermostat, collector units can be equipped with recirculation systems that maintain a comfortable temperature of the coolant in the supply of about 35–40 ºС.
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Floor arrangement is one of the most important points during renovation or construction. And if we're talking about about a private house, this question becomes even more acute. In many house projects, floors are often designed on the ground; this is quite reliable and one of the most practical and inexpensive options. Currently, heated floors are becoming more and more in demand and popular every day, so many people prefer this type of heating in the house. Reliable thermal insulation of the floor will provide warmth and comfort in it, and will also significantly reduce the cost of its maintenance. After all, heated floors perfectly retain heat in the house, create comfortable living conditions, and in some cases replace central heating.
What is a heated floor pie on the ground?
When arranging floors on the ground, it is imperative that they thermal insulation, thanks to this, a multi-layer structure is obtained, which is very often called a heated floor pie. This design In many ways it resembles a layer cake, as it consists of several layers. I would like to say that the construction of a floor on the ground largely depends on the condition of the soil. It must meet certain requirements. For example level groundwater must be at a depth of 5-6 meters, the soils should not be loose, for example, sandy or black earth. In addition, it is necessary take into account the load on the floor. It should be noted that the heated floor pie must provide:
- thermal insulation of the room;
- protection from groundwater;
- soundproofing in the house;
- prevent the accumulation of water vapor inside the floor;
- provide comfortable living conditions.
What does a heated floor pie on the ground consist of?
By its design, a heated floor pie on the ground consists of several layers, each layer is laid in stages.
Depending on the design features floor and some other important factors, the underfloor heating layer on the ground may have a different composition and different thickness.
Advantages and disadvantages of underfloor heating
Advantages:
Flaws:
- heated floors, depending on the design features, can significantly reduce the height of the room;
- in the event of a malfunction of this system, it will be very difficult and expensive to dismantle the floor layers;
- sometimes it's quite a long and complicated procedure which it is advisable to perform during the construction of a house;
- need to take into account groundwater position.
Options for laying a heated floor pie
There are several options for laying a heated floor pie on the ground. This may depend on the level of groundwater passage, operational loads on the floor, the type of heated floor and some other factors. The above option can be considered the main one, where the main underlying layer is concrete layer. The pie is laid in another way, where the concrete layer is replaced by a sand cushion, its thickness is 100-150 mm. The sequence is the same, although ensure level base much more difficult than with a concrete screed.
Depending on the thermal insulation materials, may also be various options warm floor pie. Choosing as insulation expanded polystyrene, the laying of the pie will be as follows:
Excellent insulation - mineral wool slabs , which have high density, resistant to deformation and durable. This material It is recommended to lay it in two layers. To reduce moisture absorption, they are treated with a water-repellent composition. Expanded clay is also used as an insulating layer in underfloor heating. It's quite simple and inexpensive option. When laying the cake using expanded clay, as insulation, you don’t have to lay additional waterproofing; expanded clay also replaces a layer of gravel and screed. There are a few more pretty effective ways laying a heated floor pie using some other thermal insulation materials.
Installation technology for underfloor heating
Floors installed on the ground are one of the most good options, which reduces the costs of their construction, saves time and labor costs. A well-equipped heated floor will provide warmth, comfort and coziness in the home for many years.
