Many dream of environmentally friendly housing made of wood on the lake. But the longevity of wood is of concern. Over time, it undergoes aging and decay. Despite this, natural wood is very popular and widely used in interior design.
Wooden elements are treated with anti-mold compounds, fire fighting oils. However, these substances are not always environmentally friendly. Not many people know that there is a great alternative - wood processing fire. This method appeared several centuries ago.
In this article we will consider all the pros and cons of processing wood with fire, and talk about the features of this technology.
Technology History
The first mention of wood burning appeared at the beginning of the eighteenth century. At this time, the inhabitants of Japan massively burned cypress trees. Seeing the burnt trunks of these trees, people became interested in their properties. This was largely due to the discovery of technology. After examining the wood after firing, the Japanese realized that this processing method prevents the problem of decay, damage by insects and burning. After that, they began to apply the method everywhere. They gave the name of this technology - Yakisugi, which means "cedar longing." This is due to the fact that in Japan the cedar is most often used in construction. It is used in the manufacture of hedges, walls and facades. The method of processing wood by firing can extend its life by tens of years.
It is noteworthy that a similar processing technique existed in Russia. She became a kind of prototype of modern firing. In this case, the material was simply placed in a bonfire. At the same time, it was only partially burned. Basically, the lower part of the pillars, which were then used for construction, was subjected to fire treatment. In addition, boards for roof and floor were burned. In Russia, this method was called “smoking”.
Structural changes in wood during firing
The structure of wood is such that when layers are built up under the bark, a kind of pore appears in it. As a result, fibrous cells die. Due to the high porosity and displacement of the fibers, wood acquires the main and most valuable feature - excellent hygroscopicity. Due to this quality, it is able to give and absorb water, depending on the difference in environmental humidity and its own.
The second no less significant feature is the uneven structure. This is due to the formation of cellulosic polymers, resins and sugars during the life of the tree. Such substances are the main organic components of the plant. They also determine the main disadvantages of wood - flammability and the formation of a favorable environment for fungi and pests.
In order to reduce the susceptibility of the tree to external influences, several protection methods are used. First of all, it is autoclave heating and creosote boiling of wood. During the procedure, the material is exposed to high temperatures, due to which hemicellulose formations are destroyed. They are the main cause of ignition of wood. To carry out such an operation at home is almost impossible. But there are a number of other more accessible methods for partial blockage of pores and removal of polymers. One of them is burning wood with fire.
Many people do not understand why to subject wood to such processing. Experts know that firing helps to narrow the fiber channels of the tree. In addition, they are clogged with resins and combustion products. Due to this, the service life of wood is extended by tens of years.
Properties of burnt wood
Japanese wood processing with fire gives the material a special shade and emphasizes its natural bumps. This method is different from the rest. After Japanese languishing, the wood can be impregnated with various oils once every 4 years, which allows to extend its strength. In addition, paint can be applied to the surface. However, after processing the wood with fire, few people want to change the color of the material.
Types of firing
The appearance and decorative value of fire-treated wood can be different. It depends on the purpose of the material, the technology of its processing and the firing depth. To date, there are three types of firing, differing in depth.
Full firing
This type of wood processing by fire is carried out by placing the material in a vacuum oven. The temperature in them can reach 400 degrees Celsius. A wood that has undergone full firing is rarely used. This is due to the fact that, even having the initial high strength, after processing, the wood loses its mass and greatly decreases in size. In addition, its operational properties are lost. But such wood is still used in the manufacture of furniture.
Deep firing
This process is carried out in open furnaces. At the same time, the burning depth of the upper layer should not exceed two centimeters. This method is used to process used wood. The surface subjected to this method of firing, acquires an elegant appearance. Wood takes on a hue that can range from graphite to deep black. Thanks to this feature, imitation of valuable breeds is possible.
It is impossible to get such a tree color using other methods. Therefore, the material processed by deep firing is especially appreciated by designers.
Surface firing
This method is the most popular. Its essence lies in the uniform burning of wood with a gas burner. In this treatment, only the top layer is exposed, the thickness of which does not exceed 5 millimeters. The popularity of this method is due to several factors. First of all, it is the availability of the burners necessary for burning wood and the simplicity of the procedure itself. It is noteworthy that the material processed in this way acquires increased strength and an unusual texture. Surface-fired wood is used both for interior decoration and outdoor work.
Pros and Cons of Technology
Processing wood with fire has several significant advantages. First of all, this technology eliminates the use of chemicals that can cause potential harm to human health. Equally important is the simplicity of the technology. You can burn wood at home, without special skills. Wood treated with this technology is resistant to fire, which increases the fire safety of the premises where it is used. This is due to the fact that the burnt wood does not reignite. Wood treated with fire is an environmentally friendly material that is protected from the effects of fungal organisms and bacteria. During the firing process, the destruction of wood pulp particles, which represent a favorable environment for pests, occurs. A key feature is to increase the strength of the material through firing.
However, such wood has one drawback - labor costs. The firing process involves not only processing with fire, but also its preliminary cleaning, and further processing with oils and varnish.
Which wood species are best suited for fire processing
It is believed that any wood is suitable for firing. However, for those who want to get a unique visual effect, experts recommend using only certain breeds. It is noteworthy that initially only traditional cedar was used in traditional Japanese technology. Later they began to process fire with beech and hornbeam. When burned, such wood acquired a gray color, which beautifully shimmered in the light. This effect can be achieved due to the burning of the upper layer of wood.
To date, such species as maple, alder, and poplar are especially popular in roasting. If you need to get a surface with a fine texture, then in such cases larch and walnut are used.
During the construction of the baths, mainly birch is used. This type of wood under the influence of fire becomes porous and acquires low heat capacity. Due to this, under the influence of temperatures, it cannot burn the skin.
An interesting fact is that the same wood can manifest itself in different ways. This directly depends on the firing method. But in any case, it is important to properly prepare the material for processing.
The wood to be fired should have a little moisture. The maximum permissible is 13%. In addition, the material should not have traces of coatings. It must be completely cleaned. In this case, this is important, because the resinous substances that are absorbed into the wood during firing will unevenly appear on its surface. This will significantly spoil her appearance.
Does wood need additional protection after firing?
Burnt wood has a number of advantages over ordinary wood, but it still needs additional protection. After initial cleaning, its surface is treated with oil. Then the product is covered with a layer of special protective varnish. If the burnt wood will be used for outdoor work, it is best covered with synthetic wax. It, in turn, must be dissolved in turpentine. This will increase the protective properties of wax several times.
Proper fire treatment can extend the life of the wood and make it greener. It is noteworthy that today firing is also used in gardening. Fire treatment of bushes and trees in early spring allows you to get rid of a number of diseases and pests. But the firing technology in this case is completely different.