For a country house, a wooden bath, an underfloor heating system will become convenient and practical. Underfloor heating, water, the contour of which must be hidden in the underground, is able to efficiently and efficiently heat quite spacious living quarters. This is especially convenient for you to do to improve the habitability of your dacha, to create more comfortable conditions in the bathhouse.
It is not possible to solve such an engineering and technical problem by laying water pipes under a concrete screed. This affects the technological features of the structure itself and the very nature of the technology. Not every wooden floor or logs underlying the building can withstand the huge additional load in the form of a monolithic slab. The way out of this situation is to make warm floors, water, laid on a wooden floor.
Main idea and practical solution
For quite a long time, it was considered that mounting water heating circuits directly on wooden floors was not a very good idea. Mainly, the reason for this opinion lay in the characteristics of the building material. Construction wood, despite a lot of technological advantages, is highly susceptible to the effect of thermal deformation. In addition, excessive exposure to moisture also adversely affects the wood. The lightness of wooden structures and insulating properties were considered disadvantages when it came to the installation of more complex thermal and hydraulic structures in the building.
Despite the obvious obstacles, attempts to find a reasonable way out of this situation have led to the emergence of new technologies that allow you to install a water-heated floor on a wooden floor, create heating water systems in wooden buildings. The main thing is to choose the right consumables and adhere to a certain technology.
To date, there are two types of underfloor heating used in residential buildings as a heating element. We will not talk about the electrical circuit, since it has not found its development in combination with wooden structures. Let’s pay attention to the water heating system — a warm water floor, in which hot water runs through the pipes of the heating circuit.
What technical difficulties await us in this case? The principle of operation that underlies this heating system is well known and understood. It makes no difference whether the water circuit lies in a concrete screed, or skillfully hidden in a wooden floor. Water circulating through the pipeline heats the surface of the floor, thereby giving off precious heat to the interior of the heated room.
On a note: skeptics can make a remark — the tree does not conduct heat well, in addition, the wooden structure itself can be deformed as a result of heating. There is something to be said for these comments. The use of special heat-conducting plates allows you to ensure that the thermal energy will go in a strictly vertical direction, heating the floor.
Here we should say a few words about the fact that from a technical point of view, laying heating pipes on a wooden floor is not difficult. If at the initial stage you have a clear idea of what your underfloor heating should be, what type of flooring you will have, it is quite possible to make water floor heating.
We have already said that it is not always possible to solve the problem simply as you would like. For capital stone structures with concrete floors, a concrete screed for underfloor heating is very convenient. However, in most cases, wooden residential buildings, in which wooden floors are not able to withstand an additional weight of 10–15 tons. A tree, even if you are dealing with a beam system of a set, cannot withstand such a load. It does not make sense to strengthen the supporting structures during the construction of a country house or a bathhouse. This will lead to an increase in cost and to the weight of the entire structure.
For reference: any water-heated floor involves the creation of a substrate. This element is mandatory for underfloor heating of any type. Without underlayment and one floor covering will not have sufficient support.
The key point in this situation is the new technology, thanks to which it was possible not only to significantly reduce the weight of the entire structure of the heating system, but also to ensure that the heat was transferred directly to the floor covering. The substrate can be successfully covered with linoleum or carpet. The emergence of new practical and high-tech materials allows you to create an entire heating system based on wooden floors in a matter of days. When working with a concrete screed, you will have to strictly adhere to the technology and wait 25–28 days until the screed reaches its maturity.
Assessment of the condition of wooden structures. Pre-insulation
Before proceeding with the design of the “water heated floor” heating system, it is necessary to examine wooden structures, ceilings, logs and other load-bearing elements. The wooden base, consisting of boards, must be solid. The cracks existing between the boards are carefully sealed with heat-insulating materials. The floor in a wooden house is usually mounted on logs, so it is important to study their condition and location.
Condition assessment includes:
- visual inspection of the state of the surface of wooden boards;
- feeling and scraping the surface of wooden boards to assess the structure of the wood;
- elimination of cracked and sagging boards;
- alignment of lags in places of deflection;
- adding lags if the distance between existing elements is too large.
For reference: if the condition of the wooden floor is unsatisfactory (old cracked or rotten boards), it is better to dismantle such a base. The joists that hold the boards are too far apart. For a warm floor, the logs must be at a distance of at least 60 cm from each other.
There is an installation option when a warm floor is laid on wooden logs. Those. in other words, the whole structure will be on top of the supporting structures, representing an independent structure.
Old boards that do not have a marketable appearance must be treated with a jointer to make the surface of the material even and uniform. The maximum allowable height irregularities for a wooden floor are no more than 2 mm. Such care and precision is necessary for a wooden floor due to the fact that there is no substrate in this system.
Having finished with the assessment of the condition and preparation of the wooden floor, you should proceed to the insulation of the structure. Such a preliminary procedure is necessary due to the fact that all the heat radiated by the water circuit should not go down into the underground, but linger and go up.
Reinstall the lags at an acceptable distance, install the raised floor. On the logs, plywood or used boards are nailed from below. This will serve as the basis for the thermal insulation material to be laid. Steam and heat-shielding film should be laid on the prepared base. In the openings between the lags, a heater is laid on the film, the thickness of which should not exceed 100 mm. On top of the insulation, a heat-insulating film is again fixed. Only after all this, you can start laying the heating water circuit.
On a note: It is strongly not recommended to use ordinary polyethylene film as thermal insulation. Neglect of technology will lead to the fact that condensate will begin to accumulate in the subfield. Due to the accumulation of moisture, the insulation may soon become unusable.
Insulation in this situation can be mineral wool, the density of which is 35–40 kg / 3.
Installation of the floorboard and methods of laying heating pipes
At this stage, it is necessary to take into account technological subtleties. Of course, this will take a little more time, but in the future the work will already be carried out much faster. Should be said right away. The layout of the water heating circuit in this case is a “snake”. Installation of the pipeline according to the “spiral” or “snail” scheme is unacceptable for this technology.
On the prepared base, we begin laying boards that have a special configuration, equipped with special grooves. Between the boards there should be grooves measuring 20x20 mm. The edges of the boards are turned in a semicircle for a convenient inversion of the water pipe. Having made all the necessary preparations, you can lay all the boards on the prepared base. The presence of grooves and the semicircular edges of the boards are the route for laying the water circuit. This to some extent facilitates the task in the future when installing the underfloor heating pipeline directly.
Ready-made grooves for mounting a water pipe of a water-heated floor under wooden floors are shown in the photo.
Thanks to the grooves, laying the heating circuit is easy and fast. Before working with the pipe, foil is unwound over the grooves. After that, a pipe is laid in the grooves, the diameter of which should not exceed 16 mm. In order to get maximum heat transfer, the pipe is wrapped in foil, attaching its edges with staples to wooden boards.
On top of the pipe, they are attached to the boards with metal plates. According to this scheme, the entire water pipe is laid, thereby covering the entire floor area.
On the preliminary plan of the room, marks are made where the control equipment (collector, manifold cabinet) will be installed.
Important! Pipes should be laid taking into account a certain step. For the central regions of the country, where the average monthly temperature in winter is ‑15, ‑200C, the optimal step for laying is 150–300 mm.
It is better to use a stainless corrugated pipe with a diameter of 16 mm.
The final stage. Connection to autonomous heating system
After you have laid the water circuit, you can start connecting it. For manual control, the connection is simply made to the main pipeline using a conventional tap. If you want to make the system adjustable, warm water floors under the wooden floor are equipped with mixing units and a collector. In this case, you get a convenient, efficient and adjustable heating system.
For those who want to improvise should remember! Under no circumstances should underfloor heating be connected to a central heating main. Connecting additional heating devices, including underfloor heating, to a centralized heating system and hot water supply is not legal.
Based on this, it is impractical and risky to install a water floor in a city apartment. For a private house or for a summer residence, this option is quite acceptable and effective. After connection, the water circuits must be pressure tested. The procedure is mandatory and allows you to identify places of coolant leakage, identify zones of low heating. Only after that you can start working with flooring.
Finish. Floor covering flooring
The cover you choose can be anything. To date, the trading network has a huge selection of a wide variety of materials. You will have to choose not so much for manufacturability as for cost. If you prefer to use laminate, then you will need some time for this. The costs will not be so high in this case.
On a note: any material has its own coefficient of thermal conductivity, so your level of comfort and heating efficiency depends on what kind of coating your warm floor will be covered with.
Wood has a low thermal conductivity compared to ceramic tiles. Before starting the installation of a water heated floor along the logs, thermal calculations should be made to give an idea of the amount of heat that will be on the surface. By doing everything correctly and in accordance with the technology, you can independently make an effective heating system in residential premises.