Protection and Warming of Wood

Protection and Warming of Wood

Wooden walls, like any others, need to be protected from moisture, as well as insulated. In this case, however, there is a specificity, there are a number of differences and features, which will be discussed.

In ancient times, there were few ways to protect a wooden hut from cold and moisture. So that water does not penetrate into the logs, their ends are trimmed with an ax, sealing the pores of wood in this way; and the gaps between the crowns were covered with moss or tow. Ancestors did not know effective heaters, so they tried to use logs thicker. However, too thick logs were difficult to lay in crowns, there were limitations in thickness, and therefore the ability of walls to keep heat in the house had its limits. So that the house does not stand in severe frosts, low ceilings and small windows are made in the rooms, and a massive Russian stove is built in the center. The base of the hut was sprinkled with earth, this embankment was called the “mound” and it looked, of course, not very presentable.

It was possible to solve the problem of warming and protecting a wooden house from atmospheric and soil moisture later, when special thermal and waterproofing had already appeared. This allowed us to build wooden houses with high ceilings, large windows, frost-resistant walls, etc. Although, of course, the problems did not completely disappear, and one of these problems is to preserve the very appearance of a wooden house and all the advantages of living in an environmentally friendly housing of this type.

You must admit: it’s not good that a log or timber house is reliably protected from cold and moisture, but at the same time it is crammed with a variety of “synthetics”, and even looks completely non-wooden.

One of such ways of warming is to brick the wooden house. At the same time, experts recommend that you check whether the foundation can withstand the increased load (the brick is heavy!), And also begin facing the masonry only after the process of shrinkage of the log house is completed. The brick in this case should be separated from the tree by a gap of at least 40 millimeters, which opens from above into the space under the roof. And so that the cladding remains stiff, the brickwork is connected to the wooden wall with special ties – strips of non-ferrous metal. There are other conditions, in particular the installation of a vapor-permeable membrane, the treatment of bricks with water repellents, but even under all conditions, the game, as they say, may not be worth the candle. If the house looks like a brick, why do you need to translate the forest ?! Isn’t it easier to build it from aerated concrete, which in itself is a heater, and then sheathe it from the inside with a lining?

In the same way, widespread multilayer stucco facade systems are unsuitable for warming a wooden house. When such a system is installed, a heat-insulating material is attached to the load-bearing wall, it is covered with a reinforcing mesh, on which the base and decorative layers of plaster are applied. And although these systems have proven themselves very well in the construction of houses made of bricks and cellular concrete, in the case of wooden houses, stucco with insulation and other components of the “puff pie” literally kills the unique look of natural wood. This means that here the tree was used for nothing. A similar method of insulation can only be recommended for the repair of an old or dilapidated wooden structure. It may happen that the wooden facade can no longer be restored to its original form, it can only be updated by covering it with some kind of finishing material. And here the facade system in combination, for example, with siding can be very useful.

The negative examples from this area do not end there. It happens that the owners of wooden houses rely on the fact that a tree, as a material with low thermal conductivity, in itself will protect the house from cold. Therefore, some simply plug the slots with moss, lay some dense material such as cardboard or roofing felt under the outer skin, and calm down on this. However, it should be said that in this way only the buildings are not windproof, and not insulation at all. Moreover – a layer of roofing material can even contribute to dampening of the room, except that it will be cold in it.

Buffer for the cold

Having examined the examples “from the contrary”, we turn to the positive experience. To begin with, the warming of a wooden house is not only about laying this or that insulation on the wall. There is, if you like, an architectural way to preserve heat in the house – the installation of glazed verandas around. Air is known to be a good heat insulator, and a veranda in cold wintertime effectively reduces heat loss through walls. Various utility rooms, which are arranged along load-bearing walls, can also play the role of a similar buffer. But if the project of your house does not provi

One of the important operations in the construction of a chopped house is the compaction of the interventional space. For this purpose, traditional materials such as linen and hemp tow are most often used (moss and wool felt, which have a number of drawbacks, are practically not used at present). An even higher quality of sealing is achieved as a result of the use of a special insulation fabric made of bast fiber of jute. Such a canvas is a finished product intended for direct installation in a log house. It comes in the form of a tape, thick and wide, suitable for building a house from a certain type of timber or log. The use of a sealing web significantly speeds up the assembly of a log house, ensuring the reliability of inter-crown joints.

The technology of applying insulation cloth is very simple. The strips are bent along the long side and laid between the crowns, not reaching 5 mm to the ends of the beam. The number of layers and the thickness of the insulation sheet is selected based on the quality of the building material. If the beam is behaved, uneven and damp, then you need two layers of thick canvas with possible additional tabs in the voids. For a glued beam or a flat log, one layer is enough.

Thermal protection of wooden walls is performed when they are facing from the outside or inside. In this case, it is mandatory to solve the problem of condensate, which can accumulate in a wooden wall, thereby contributing to its destruction.

In the cold season, the temperature inside the wall is lower than room temperature, therefore, when warm steam enters the wall and when in contact with cold zones, condensation forms. This process proceeds continuously, causing moisture accumulation, dampness, and fungal diseases of the wood. When engaging in thermal protection of walls, it should be remembered that the thermal conductivity coefficients of permeable insulation (mineral wool plates, glass wool, etc.), which are given in the reference literature, are measured under conditions that are far from real. In reality, heat transfer by air passing through the insulation moisturizes it, reducing heat-shielding properties. That is why it is impossible to completely avoid wetting the walls of the house, you can only minimize the amount of moisture and ensure its removal in the direction of the street. For this, special materials of domestic and foreign production are used, which are vapor-removing insulation, which provides moisture removal from the insulation and internal wall structures.

Multilayer constructions – combinations of a load-bearing wall and a layer of effective insulation, closed on the outside with decorative wood paneling, are widely used in modern construction practice. Typical mistakes made in this case include the installation of a vapor-tight layer (glassine, roofing felt, vinyl film, etc.) from the outside of the insulation. Whereas in winter, the movement of water vapor through the enclosing structure occurs from the inside of the room. And if the insulation is insulated from the outside, then its moisture content may increase by 20% during the season. This entails a multiple decrease in the efficiency of insulation and increased consumption of funds for heating the home. In addition, external vapor barrier prevents the removal of moisture outside the enclosure and contributes to the formation of mold and fungi.

In addition to the external walls of the wooden house, it is necessary to insulate the internal ceilings, walls and partitions. This allows you to improve the microclimate of the premises, provides good sound insulation, etc. Attic flooring, as well as the foundation, require special attention, because not only energy consumption, but also the safety of the supporting structures of the building depends on its heat insulation.

So, mineral wool insulation along the perimeter of the building under the blind area reduces the effect of frost heaving on the foundation. A comfortable humidity and temperature climate in the house is achieved only if all the building elements in contact with the ground are thermally insulated.

Barrier to moisture

A wooden house also needs to be protected from moisture. In houses without a basement, built on concrete and stone foundations, waterproofing works are usually limited to a protective layer between the foundations. To do this, between the concrete and the wooden wall structures, a waterproofing strip is made of roofing or roofing material. In homes with a basement, these measures are not enough, especially when the groundwater level is high.

Protective construction against moisture helps to waterproof the walls and bottoms of the underground part of the house. In the construction of such wooden buildings, coating or painting: asphalt, gluing and rigid waterproofing are used.

Coating waterproofing is a continuous waterproof layer of bitumen mastic with a thickness of 4-5 mm. Paint waterproofing is a type of coating and is applied in the form of a layer of a coloring composition – 0.2-0.8 mm. It is designed to protect structures from capillary moisture without hydrostatic pressure. Coating (painting) waterproofing is used both indoors and underground, and only from the side of water backwater. Bituminous materials are made in the form of solutions of bitumen and sand, sometimes used with fillers and special additives. Paint formulations are made from ethanol varnishes mixed with asbestos and dyes.

Asphalt waterproofing is a continuous waterproof layer of asphalt mass 10-15 mm thick, created on horizontal and inclined surfaces of the basement of the house. It is applied in hot or cold form with emulsion pastes and mastics with an admixture of 3-4% cement. Hot asphalt mastics acquire waterproofing properties immediately after cooling, cold – after drying.

A layer of plaster made of cement-sand mortar is called hard waterproofing. The waterproofing layer is applied to the walls, floors and ceilings of the basement of the house. Traditionally, waterproof non-shrink cement or Portland cement with sealing additives was used for the waterproofing layer.


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