How to make a water-heated floor in a wooden house
Among the many types of heating to install a water-heated floor in a wooden house is the most difficult. Here it is necessary to take into account the construction design of the building, correctly select the floor covering and precisely follow the installation technology.
Types of warm water floor in a wooden house
There are different ways of arranging a warm floor in a wooden house. If we talk about the water version, the pipes can be mounted in two ways:
- dry installation means laying pipes on wooden beams or logs;
- The classic method of laying pipes in cement mortar. At the top of the thermal contour, a tie is made with a thickness of at least 30 mm.
Before choosing one of the methods, it is necessary to carefully study the structure of the wooden house. Quite often, concrete floors are installed on the first floor, especially if they serve as a basement ceiling. In this situation, you do not need to reinvent something, but just need to put coolant under the screed.On top of the concrete, you can make any flooring, even from wooden boards. Installing coolant on a concrete base along beams or lags will only lead to additional costs that did not meet the expected result.
Another thing, if the house on all floors has a wooden ceiling. Here it is appropriate to apply only the dry method. This is due to the following nuances:
- Concrete screed has an impressive weight, creating a large load on the wooden floor, and it simply can not withstand the entire mass. Do not forget that this will add to the weight of the installed furniture and heavy household appliances, for example, a refrigerator, a washing machine, and so on.
- Properly built wooden house tends to "breathe." Wood itself, under the influence of wet and dry air, “plays” a little. These processes will lead to cracking of the screed. This can be avoided by taking additional measures aimed at compensating for the expansion of the heat supply circuit, which will bring additional costs and installation difficulties.
Particular attention should be paid to the device of new houses from wooden lumber. Often in their construction use undrawn material.In the process of drying the wood will be slightly deformed, which will lead to the complete destruction of the concrete.
Choice of the heat carrier
As a heat carrier for a water heated floor, you can use several types of pipes:
- metal-plastic pipes keep their shape steadily on bends, are easy to install, have an affordable price;
- pipes made on the basis of cross-linked PET can be easily repaired and are not afraid of freezing of water inside, if this happened due to unforeseen circumstances. But it is inconvenient to work with them. On bends, it is difficult for them to give the desired shape, and during the heating of PET the pipe has the ability to straighten;
- copper is a very good heat conductor. However, copper pipes are very expensive, and if they are laid under a screed, you will have to make a protective layer that protects copper from alkaline oxidation.
Before the construction of a heated floor it is necessary to make its calculation. With this, it is better to turn to specialists who will take into account heat losses, power, select the optimal pipe diameter, etc. If you decide to do everything yourself, you must adhere to the following recommendations:
- You can save on pipe laying in places where there will always be plumbing or furniture. Why is it useless to heat a fully enclosed area of the floor? This will bring only extra costs for heating and the purchase of material for floor heating.
- Each contour should occupy a floor area of not more than 15 square meters. m, otherwise the water pressure inside the system will be below normal. For example, a 16 mm pipe in one circuit should not exceed 100 m.
- For large rooms it is better to make the device of several uniform heat carriers. The difference in the length of the pipe of all circuits shall not exceed 15 m.
- On condition of good thermal insulation of the house, it is sufficient to lay the coolant pipes at a distance of 150 mm from each other. For cold regions with frequent frosts below 20aboutC, the distance between them can be reduced to 100 mm. This is especially true of the location of pipes near the outer walls.
When calculating the approximate consumption of the pipe, keep in mind that when it is laid at a distance of 150 mm from each other, you will need about 7 meters per square meter. m floor. At a pitch of 100 mm, the consumption of the pipe will increase to 10 meters per square meter. m floor.
It will not be out of place to draw on the paper the outline of the contours.It will need to determine the position of the pipe during the repair of the floor.
Dry installation method
Wooden logs and beams serve as carrying elements of the floor construction. Mounting lag is made on a solid solid foundation or a large number of supports are built under them. The emphasis of the beam is carried out only at two points - this is its edge. Sometimes an additional emphasis serve as partitions.
Due to the fact that the beams are load-bearing elements of the floor, cut them into the grooves for the passage of pipes can not. To perform a dry installation of the thermal circuit, it is necessary to make an additional structure - a subfloor. It can be built from chipboard or any wooden boards.
The question of lags is completely different. If the timber lies on a solid base, it can be filed to make the grooves for pipes. The need to build a subfloor here is eliminated. But when lags have not a continuous emphasis, but at several points, they, like beams, cannot be filed.
In any case, if the installation of a subfloor will be performed on top of the beams or logs, a layer of insulation is placed between them. On the first floor it is laid with a thickness of 80 mm, a layer of waterproofing under the bottom.For interfloor overlaps, 30 mm of insulation thickness is sufficient.
Pipe laying methods
The thermal contour on the wooden floor is laid in two ways:
- The installation of pipes according to the modular scheme is carried out into ready-made modules having special grooves inside. This method is simple, because it eliminates the self-tamping of rails or cutting grooves;
- The rack mounting method is a bit more complicated than the previous one, but it is more accessible to every builder if there are no ready-made modules at hand. The grooves for pipes do a width of not less than 20 mm from the slats of OSB or particleboard.
Before construction, you must carefully examine the wooden base. It should consist of firmly fixed whole boards without rotten areas. An important factor is the lack of a draft under the boards. Lags must be no more than 600 mm apart. If at least one of the problems exists, it will have to be fixed before construction.
It is necessary to pay attention to the evenness of the board. If a laminate is chosen for the finishing flooring, it will be necessary to make a perfectly flat surface with a deviation from the norm of no more than 2 mm.This is due to the fact that the laying of the water heat exchanger does not include the use of the substrate.
Making a subfloor
Having brought the lags to the standard requirement, that is, having kept a distance of 600 mm between them, they begin the installation of a fake floor. It will fall to him the whole mass of the insulator:
- On the underside of the lag, any boards or plywood are nailed, you can even second-hand.
- A vapor barrier is laid out on top of the resulting fake floor. It is impossible to use PET film for it, since condensate will appear on it due to the temperature drop.
- The next layer is laid out insulation of mineral wool, polystyrene foam or another, the choice of the owner.
- Along the perimeter of the room glue the compensation tape. It will protect the floor construction from extensions.
- Then it is time to fix the draft boards. A heat exchanger will be mounted on top of them. Fixing boards, it is necessary to make the grooves for pipes. The dimensions of the groove should have limits of 20x20 mm. All the ends of the boards where the pipe will pass must be made semi-circular. This will create a smooth turn of the heat exchanger tube through 180about.
Heat exchanger installation
Foils or special heat-reflecting plates are laid into the grooves on the subfloor. They will direct the flow of heat up.A pipe without any connections is laid out in the heat reflector cells, fastening it to the floor with metal plates. They will prevent the tube from accidentally popping out of the slot.
The laid heat exchanger remains to be connected to the heating system. Here you can set the manual adjustment of the heat supply taps or make a connection to the mixing units. The choice is big, it all depends on the wishes of the owner.
After successful testing, a dry warm floor can be covered with a finishing floor covering.
When installing the heat exchanger under the coupler, it is necessary to check the flatness of the concrete base with a two-meter rail. It should not have differences of more than 7 mm.
The process of waterproofing laying insulation
Before laying insulation do waterproofing grounds. It can be performed under insulation, on top of it or on both sides. It all depends on the properties of the material. For example, polystyrene is resistant to moisture, and the location of the waterproofing is not so important. But it is necessary to ensure that the cement milk does not leak between the joints of the expanded polystyrene plates and then not absorbed into the base.In addition, waterproofing will prevent the passage of moisture from the bottom of the base.
The waterproofing material is laid out overlapping, gluing the edges with adhesive tape. At least 200 mm is wrapped on the wall.
Installation of the damper tape
The dimensions of the damper tape are within 80x150 mm. It is glued around the perimeter of the room above the fill level. For reliability, the tape is screwed to the wall with screws.
Reinforcing mesh fits under the heat exchanger and on top of it. The pipes to the grid are fixed with clamps, and the two grids are tied together with a wire. The thickness of the grid rods is sufficient 5 mm, and the size of the cells is selected individually according to the pitch of the laid pipe, so that they can be conveniently fixed.
Heat exchanger tubes are positioned from the edge of the wall at a distance of 200 mm. At this point, the pitch between them is kept at about 100 mm. Towards the middle, the distance between the pipes can be increased to 150 mm. Each contour is made of a solid pipe, no longer than 100 m. There are many schemes for the arrangement of contours, for example, a snake, a spiral or other variants.
Mounted circuits are connected to the heating system and perform pressure testing.Upon receipt of a positive result proceed to pouring the screed.
In the absence of temperature gaps, the coupler may crack with time. If the room has a non-standard form, the area is more than 30 square meters. m, the length of the wall is more than 8 m, or deformation seams of the structure pass through the room, shrink seams should be arranged before pouring the screed.
To do this, at the point of passage of the seam, a reinforcing mesh is divided and here the damper tape is placed between the parts of the tie. After the concrete has set, the place where the tape is laid is treated with a sealant.
The screed solution is made of cement grade M-400, sand and crushed stone with a fraction of 5-20 mm. The recommended mass proportion in the same order is 1: 1.9: 3.7. Properly prepared concrete during laying should not produce water. As additives it is necessary to use a plasticizer. It will give elasticity and strength to the solution. The solution is evenly poured throughout the room. Its minimum thickness above the contour should be 30 mm.
After three days, the screed will begin to gain strength, and will completely harden after 28 days.Until this time, turn on the heating is strictly prohibited.
Having installed and tested on the performance of the warm floor, you can proceed to laying the finishing flooring. This may be tile, laminate or other favorite material that has a heat transfer resistance of less than 0.15 square meters * K / W.