House of wood chips with cement. What are cement-bonded building blocks. Video: homemade wood crushing machine

The search for a universal building material, optimal in terms of its heat engineering, strength and environmental characteristics, was crowned with the invention of wood concrete. It happened in the 50s of the last century in the former USSR.

Having comprehensively studied the unique properties of wood concrete (the second name of wood concrete), Soviet scientists gave it the "green light". The main customer of the new structural and heat-insulating material was the northern regions of the Soviet Union, where the construction of wood concrete houses was progressing at an accelerated pace.

Unfortunately, at the end of the 90s of the 20th century, the use of this unique material began to decline, since it became more profitable to build residential buildings from large-sized expanded clay concrete panels.

Today, wood concrete is experiencing a rebirth and every year it is used more and more actively in individual construction. Therefore, we have no right to pass by this interesting material and not consider in detail all its pros and cons.

Advantages and disadvantages of wood concrete blocks

It should be noted that in the last century, wood concrete was used not only for the manufacture of wall blocks, but also in the form of sheets, which were used for insulation and sound insulation of floors.

Today, wood concrete is practically not used in this capacity, because its main advantages are revealed when erecting low-rise buildings. Let's list them in more detail.

- Low thermal conductivity

Wood concrete wall blocks belong to the category of effective heat-insulating materials. This is evidenced by the following fact: a wall made of wood concrete with a thickness of only 30 cm retains heat as well as a meter-thick brickwork.

Therefore, in the reviews of the owners of houses from wood concrete blocks, first of all, there is a significant fuel saving even in the coldest winters.

- Durability

The strength of wood concrete blocks directly depends on their density. For structural and heat-insulating wood concrete with a density of 600-650 kg / m3, it ranges from 20 to 35 kg / cm2. According to this indicator, arbolite practically does not differ from its main competitors - foam and aerated concrete.

An important plus is the plasticity of this material. This fact is explained by the fact that wood chips are part of the arbolite blocks that reinforce this material. Therefore, under load, wood concrete does not crack, but only slightly deforms without loss of integrity.

When building a house from wood concrete, you do not have to spend extra money and time on pouring a reinforced concrete belt, which is necessary for fragile walls made of gas and foam concrete blocks.

- Frost resistance

Arbolite has frost resistance (the number of freeze-thaw cycles in a water-saturated state) is from 25 to 50. In practice, this means that a house made of this material will stand for at least 50 years (confirmed by studies of existing buildings). In foam blocks, the resistance to freezing and thawing does not exceed 35 cycles.

Speaking about the advantages of wood concrete, it should also be said about its low carbonization shrinkage. This term denotes the process of loss of strength of cement stone due to reaction with atmospheric carbon dioxide, as a result of which soft chalk is obtained.

- Good sound insulation

For wood concrete blocks in the acoustic range from 125 to 2000 Hz, the sound absorption coefficient is from 0.17 to 0.6. For a brick, this indicator is almost four times worse. For wood, it is in the range from 0.06 to 0.1, which is also significantly less than that of wood concrete.

- A light weight

1 m3 of blocks made of structural and heat-insulating wood concrete weighs almost 3 times less than brick and almost 1.5 times less than expanded clay concrete. This allows you to significantly reduce the cost of building foundations for wood concrete walls.

- Environmental friendliness and durability

Wood concrete is one of the most environmentally friendly building materials, as it contains only natural ingredients - cement stone, wood chips, water, calcium chloride (used in the food industry) or ordinary milk of lime.

In the wall, this material behaves excellently, since it does not rot, is not afraid of mold and does not burn. In addition, wood concrete breathes well and regulates the air humidity in the room, absorbing excess moisture and giving it back in case of lack.

- Non-flammability

Arbolit belongs to the group of low-combustible materials (flammability group G1). In addition, wood concrete is hardly flammable (flammability group B1) and low smoke-forming material (D1).

- Ease of processing

Wood concrete can be easily processed with any mechanical tool. It can be sawed and drilled and holds nails and screws well. The rough surface of the blocks is an ideal base for applying plaster mortars without the use of reinforcing meshes.

The disadvantages of wood concrete blocks include low accuracy of geometric dimensions. Therefore, walls made of this material require leveling with plaster solutions or sheet finishing materials (drywall, magnesite, lining, siding).

Since the technology of wood concrete production is based on the use of wood chips - a rather expensive material, the cost of wood concrete blocks exceeds the price of aerated concrete by an average of 15-20%.

1m3 of wood concrete blocks (500x250x400 mm) costs from 4000 to 5200 rubles, while manufacturers offer aerated concrete blocks at a price of 3400 to 3800 rubles.

Wood concrete production business is one of the most interesting at the moment. This is due to the high (and growing) popularity of the material among end customers, with the simplicity of manufacturing wood concrete blocks, and finally, the lack of time-tested manufacturers plays an important role.

Federal retail "" invites you to consider purchasing. At the same time, we will not only supply you with the currently best equipment on the market (we have been producing it for 10 years, the former name of the Russian Arbolit company is the Experimental Design Bureau “Sphere”), but we will also ensure that your capacities are fully loaded with our orders.

We make wood concrete blocks ourselves

Considering the rather high price of high-quality wood concrete, many developers have a natural question about the possibility of their own production. At first glance, it seems that there is nothing complicated in this process: I mixed cement with wood chips, added water and mold blocks for myself.

However, making an arbolite with your own hands on your site will be much more difficult than in theoretical reasoning.

Firstly, almost all home craftsmen presenting their own technologies making blocks with the addition of chopped wood, in fact, they are not talking about arbolite, but about sawdust concrete. This is a fundamental difference. Sawdust concrete is not only significantly different in composition from wood concrete, but also worse in its strength and heat engineering characteristics.

Secondly, wood concrete chips must meet fairly stringent requirements.... Its thickness should not exceed 5 mm, and its length should not exceed 25 mm.

Therefore, in production, all wood is first passed through a crushing machine and only after that is mixed with cement.

Thirdly, sucrose is a serious enemy of the strength of wood concrete blocks.... It is contained in wood and must be neutralized. To do this, enterprises use safe calcium chloride or aluminium sulfate. You may not have these substances at home.

If you nevertheless found a suitable fraction of wood chips for wood concrete, then the sucrose neutralizer can be replaced with a solution of slaked lime. Chips must be kept in it for at least 3 hours. Another option for replacing sucrose neutralizers is to keep the shredded wood pulp outdoors for 3 months.

The simplest equipment for the production of wood concrete blocks includes a mortar mixer and a forming vibrator. The cost of such a kit is about 58,000 rubles, so it will pay off only on condition of large production volumes (building a house or a private business).

The initial mixture for the manufacture of wood concrete blocks is prepared in a ratio of 4: 3: 3 (water, wood chips, cement)... Sawdust and shavings can be added to wood concrete, but their amount should not exceed 5-10% of the total volume of wood raw materials.

The wood-cement mortar is mixed in a concrete mixer until a homogeneous mass is formed. It should not be watery, but crumbly. When squeezed in a fist, the resulting lump should keep its shape well and not fall apart.

After placing the mixture in a metal mold, it is vibrated on the machine, after which the finished block is placed under a canopy for 3 weeks to gain brand strength.

Useful video

Wood concrete, otherwise, arbolite, has unique thermal insulation properties, thanks to which it is successfully used in the construction of houses.

This material should not be confused with sawdust concrete, in the production of which sawdust and sand are used. In the case of obtaining the material in question, wood chips for wood concrete are made from wood waste, since this is the most economically profitable due to the cheapness and availability of metalwork waste, the block itself can be made by hand.

Wood concrete composition

This material is endowed with unique heat-conducting properties due to its constituents. Like all concrete blocks, it contains a binder in the form of cement; in most cases, Portland cement of the M400 or M500 brand is used in the production of this material.

The main filler, which occupies almost 90% of the volume of the material, is wood chips.

Chemical additives can make up 2-4% of the total mass of the concrete block. They increase its strength and, combining with the sugars present in the wood, form compounds.

In some cases, sand and slaked lime are added to it.

The water used to dilute the building composition is poured into the solution in a warm form, its temperature should be +15 0 C. If it is less than this value, then the setting rate of the cement composition will be lower.

The exact proportions of the components of wood concrete depend on the selected brand.

Wood chips used for wood concrete

This wood material in the production of wood concrete Loka can be used in several types. But not any shavings can be suitable for this process, but only those that correspond in geometry and dimensions to GOST.

Chips obtained from wood must be needle-shaped and fit into the following dimensions:

in length 15-25 mm;
in thickness 2-3 mm;
in width 10-12 mm.

To cook it with your own hands, you need to use special chipping machines, which in a short time are able to process various knots and tops of trees, waste from the woodworking industry and slab into chips. For the manufacture of wood chips, coniferous trees are most often used: pine, spruce, fir, birch and aspen have also proven themselves well, but beech and larch should not be used.

Sometimes crushed bark of trees and their needles are used as chips, but they are mixed together with the main filler.

Before use, the selected wood material must undergo an antiseptic treatment, and it is also freed from water-soluble substances that can reduce some of its performance characteristics.

If there is no place to get the necessary tree, then you can use hemp or flax fires, rice straw, or cotton stalks. Before use, flax fires must be soaked in milk for two days or kept in the air for a long time, about 4 months.

Chips after production or purchase must be sieved, cleaned of dirt and bark. Then it must be dried, and to give plasticity it must be treated with silicate glue or calcium chloride. To shorten the drying time, you need to use water glass, but the finished blocks in this case are more fragile.

Purchase of chips and wood for her

Raw materials for the production of chips can be found in forestry and an agreement on the purchase of a certain volume will be agreed, the costs of transporting it will be borne by the buyer, and if you buy wood from private companies that are intermediaries, then the delivery will be included in the cost of the material.

The chips themselves can be purchased from private firms that have purchased the appropriate equipment and produce them for sale. Or you can buy the desired chipper and make chips with your own hands, it will turn out much more economically.

DIY wood concrete chips production

It is most profitable to build a house from material made by yourself from start to finish. To do this, you need to purchase the necessary materials and equipment. Chips can be made from wood, which is purchased "for future use" and stored in a place protected from the weather, as well as from metalwork and forestry waste.

The most important attribute of receiving chips is chipping machines, they are also called chippers. There are several types of them, the work of each of them is slightly different. You can purchase machines:

hammer;
drum;
disk.

The final choice will depend on the volume of production, because you can set up the process of getting wood chips with your own hands, not only for your own needs, but also for sale, this type of activity will quickly pay for itself, since such material is in great demand not only in construction, but also for heating housing , and even for landscaping.

Before buying any of the above types of devices, you need to choose a place for its installation, think over free access to the loading window of the device, and also how chips will be collected, flying out with great force from the device. Many people miss this moment, and small material is scattered throughout the place of production. Some set aside a small hangar for it and, after stopping the machine, collect the resulting material with a shovel.

Hammer crushers

Such crushers are single-shaft and twin-shaft; for home production, the first type is sufficient. It is a rotary device that contains hammers and bumpers in its core. The unit has a special hopper. It is necessary to lay thin logs prepared in advance in it, it is better to make them long or buy them, this will secure the process, otherwise, if the short workpiece is handled awkwardly, there is a high probability of injury.

When a tree enters the device, it passes between the hammers and dividing plates, splits on impact, and then sifts through the grate holes into the outlet compartment. The size of the chips will depend on the mesh size of the sieve, its maximum size usually does not exceed 6 mm.

Disc chippers

Some of their models have adjustable knives, due to which you can change the size of the resulting chips.

They are designed for processing any wood, including round, the beams of which must be loaded into a separate window, where it, falling on the knives, is pulled into the depths of the device by them and splits. The maximum diameter of a log is 10 cm.

Drum chippers

You can recycle not only wood, but also waste from furniture production, sawmills. Models of such wood chip cutters are equipped with a large loading hopper, into which branches and logs must be fed, they are self-drawn into the device, and after passing through the drum with double-sided sharpened knives located on it, chips of the required size are obtained. Small models have one wheel for easy transport of the unit.

To simplify the process of producing chips with your own hands, you can make a whole line, which will consist of a chip cutter, a chain conveyor and a debarking drum.

The principle of operation of such a system is simple:

raw materials are loaded into the machine to obtain chips;
at the exit, the finished chips fall on the conveyor;
the device delivers the material to the debarking drum;
after reaching the desired cleanliness, the contents of the drum are unloaded onto a chain conveyor, which feeds the chips to the storage.

Human participation in this process is minimal.

The process of obtaining chips for the manufacture of wood concrete is not difficult, if you first allocate a place for the installation of equipment, choose it for a specially designated place. Material loading is done manually in order to protect yourself, it is better to use long workpieces, and in the case of using a large hopper, you can load smaller raw materials using a shovel.

Two kilometers from Lake Naroch 20 years ago, a unique for Belarus type of settlement appeared - the ecological settlement Druzhny. By its very existence, it proves that high-quality and budget housing can be built from the simplest materials: wood, straw, wood chips and clay. And this option for solving housing issues in the countryside may well become an alternative to construction in agricultural towns.

Helped the whole world

The Germans, who first visited our country in the early 90s, were so impressed by the scale of environmental and economic problems that they had an idea to help families who lived in contaminated areas move to more favorable regions of Belarus.

A group of German volunteers began to build the first houses in Druzhny on Naroch in 1993. The land for the settlement for displaced persons was allocated by the authorities in the Myadel district of the Minsk region. There was also an agreement with the chairman of the local collective farm, who thus wanted to attract labor to his farm.

When choosing materials for construction, the Germans focused on their environmental friendliness and availability in this area. With the shortage of everything existing at that time, including building materials, there was practically nothing to choose from. But wood, straw and clay were in abundance.

Yuri Suprinovich

On the Belarusian side, the International Charitable Public Association “Ecodom” took part in the project “House instead of Chernobyl” (in 2014 it was renamed “EcoStroitel”). Its representative, Yuri Suprinovich, says that then, under the goals of the project and the existing material base, it was necessary to choose a construction technology that would allow people to build a house without any special skills. As a result, a German frame house with filling the walls with a mixture of straw and clay was chosen for the model.

Volunteers from Germany came to build the first houses. Among the German volunteers there were specialists who performed two tasks: they supervised the construction and taught the technologies of the others: now there are probably more adobe construction specialists living in Druzhny than in the whole country.

At first, they built houses with straw filling, later they switched to wood chips: it turned out to be easier to work with, the material itself is just as cheap and affordable.

The combination of free work of volunteers and the low cost of “foot” building materials made it possible to erect 14 houses (now there are 31 of them) by the official opening of the eco-village in 1997.

In order to move from a radiation-contaminated area to a clean one and at the same time receive a new house for free, applicants were selected. One of the main criteria is the desire to contribute to the construction of the village.

- My family and I moved here from Khoiniki district in 1994, - says Valentine, one of the very first eco-settlers. - We saw an ad in the newspaper, which said that a German charitable organization would build houses on Naroch for immigrants from contaminated areas, there would be a selection among those wishing to relocate. We didn’t really count on anything, but we wrote a letter. Two weeks later, the answer came: come.

Valentine's family was among the first eight to qualify. But only two of them stayed here. The rest were scared and refused to move.

“You can understand them,” says Valentine. - We arrived here on March 20, 1994, and here is an open field. It is now here a road, trees, houses, but then it was slush, mud, a collective farm ... As soon as they looked at all this, they immediately left. Because it was not clear whether there would be a kindergarten, school, shop, work. It was a difficult moment. This is not the same as arriving in Minsk and giving you an apartment.

The settlers first built their own houses, then helped others. The collective farm paid them wages as builders.

- We were told that houses will be built of clay and straw. We thought that the straw would be only for the bunch, and the rest of the clay, to make it stronger. But everything turned out to be wrong. First, clay is mixed with water in a concrete mixer, resulting in "sour cream". It was poured into a dug hole 3 × 3 m and straw, which was brought by the collective farm, was added. And all this was mixed and trampled underfoot. Then the straw in the clay was thrown onto the wooden flooring, so that it would flow around and wither. Then she was sent to the formwork, fixed on a wooden frame, rammed. To be honest, I didn’t believe that something normal would turn out right away. But when the formwork was removed, I saw that the walls were even, neat. And now 22 years have passed - nothing has rotted. I also remember that everyone was afraid - the mice would stretch the straw. But they are not in the walls. It’s nonsense that there’s someone chewing through the passages.

Clay and straw inside the wall of one of the first houses: after 20 years it is dry inside, no mice

Valentin said that they worked at the construction site side by side with the Germans. Our people were greatly impressed by their technical equipment.

- In 1993, German carpenters arrived, so they had so many tools - for all occasions. We never saw such things: circular saws, tools to spike the frame parts ... We were afraid to take them into our hands right away, before that we knew only axes and hand saws. Then they saw the "Calm" chainsaw for the first time!

Valentin says that he did the first renovation two years ago - he renovated the facade.

Previously, the facades were sheathed with clapboard. Now many are changing it - for 20 years the paint has peeled off from them, in some places the tree has begun to rot. But the walls themselves underneath are in excellent condition. They are insulated and plastered. In the first houses, clay plaster was applied without reinforcement, so it cracked in some places - I greased it, and we continue to live. I decided not to change the staircase that the Germans made for me, even though it creaks. Then, in the 90s, dry lumber was not found, so it was collected from raw boards. Well, she creaks, but it's not scary. The second floors are insulated to a minimum - only 15 cm of straw and clay between the rafters. I had to additionally insulate over time. But this is in our first homes. Warm attics are already being built. But what no one in the village will complain about is the dampness. In our houses, there is always normal humidity - even heat it, even keep it cold.

German pellet boiler

By the way, in almost all the homes of the settlers, in addition to the modern water heating system, there are also stoves. Just in case.

Now houses in the village are heated with natural gas. But a public house, also known as an "office" and a house of creativity in combination, is heated by a pellet boiler with automatic feeding. Valentin says that 3 tons of pellets are purchased for the season. The heating system has solar collectors that work in tandem with the boiler. Thus, the house is heated and hot water is always available.

There are not so many children in the village as before - they grew up and left. But the local children's art house is not idle. Valentine says many families have adopted foster children. Circles are organized for them.

Ecovillage public house

Now Valentin looks after the common house, maintains the wind farms, which are located on a hill next to the village. He is not going to leave Druzhnaya.

- Houses passed into our ownership after 10 years, before that we had no right to sell them. It was believed that if he lived here for so many years, it means he took root. Most of the settlers stayed here. And I got accustomed, although sometimes I go to my homeland. I can say that people live better here. There are many drunken people, there is practically no work ...

There are houses for sale in the village of Druzhnaya, but there are no options for a “penny”.

- The houses here are excellent - all communications, large plots, near Naroch. A neighbor recently sold it to someone for a dacha for $ 26,000.

New settlement in Old Lepel

A similar settlement appeared in the Vitebsk region - in the village of Stary Lepel.

- Representatives of local authorities came to Druzhny - they liked this model of the settlement, and in 2001 they invited them to their place, allocated a site, - says Yuri Suprinovich. - By this time, the legislation had already changed, new requirements for the energy efficiency of buildings under construction had appeared. Therefore, new houses have already been built with additional insulation.

All our constructed public buildings - an outpatient clinic in the village of Zanaroch and a social rehabilitation center for the disabled - are heated with pellet boilers and solar collectors. This increases the initial costs, but with further operation, they pay off.

Photo from the site www.oekodomstroj.by

Yuri says that mineral wool or expanded polystyrene are not environmentally friendly materials, and there were no others on our market at that time. Focused on Europe. There were already options from flax fiber, cane, cork, hemp, ecowool.

As a result, they decided to make insulation from reed - there is plenty of it in the country. Moreover, it is a constantly renewable resource. This is how the first Belarusian production of reed slabs appeared.

- We learned how to harvest the reed ourselves and now we use it as thermal insulation for our houses. The most interesting thing is that we did not come up with anything new - even in the USSR there was a building material called "reeds". Today, the company "EcoDomStroy" provides reed mats not only for our facilities, but also sends them for export, uses them to insulate houses at the request of the population

Reed is harvested in winter on ice on Lake Naroch. There is a special self-propelled harvester for this. Local residents also have extra income, harvesting and selling cane to the grower.

Reed slabs are manufactured on special German machines. They are very old, made in 1948.

"I know that I'm building"

From wood chips and clay now build not only according to social programs. They are also ordered privately. One of these houses is now being erected on the banks of the Vileika reservoir.

Its owner, Vyacheslav Makushinsky, heads the Belarusian-German society “Children's Rehabilitation and Health Center“ Nadezhda ”. He told the site that he was familiar with the technology and, in his opinion, it worked well.

Vyacheslav Makushinsky, head of the Nadezhda educational center

- For the first time I got acquainted with this technology during the construction of two guest houses in the institution, which I manage. We built the first house using frame technology with filling the walls with ecowool, the second with clay and wood chips. Therefore, I already have practical experience in both the construction and operation of such houses. When I decided to build for myself, the choice was predetermined. It was important for me that the materials were as natural as possible. Ecowool is also a natural material, but already transformed. Clay, wood chips, wood for the frame - all these are exclusively natural materials.

Now builders are busy filling the walls with a mixture of wood chips and clay. It is kneaded in a large concrete mixer - up to 0.8 cubic meters can be cooked in it at a time. With a construction wheelbarrow, the mixture is brought to the workers, who fill it with buckets into the removable formwork and ram it. In total, 7 builders are involved in the construction site.

Unlike standard frame houses, which are built from small-section technical drying lumber, a timber of natural moisture with a section of 120 × 120 mm is used for these frames. After the outer walls are filled in and the roof is installed, partitions made of ceramic bricks will be erected inside. After that, construction work will stop until July next year: the house should dry out by this time, the chips should shrink. That is, such a frame house cannot be built in one construction season.

It took 25 cubic meters of wood chips to build this 130 square house, without an attic floor. Clay was "mined" right on the site, when they dug a hole for an autonomous septic tank. At first glance, the technology is simple and looks attractive in terms of financial costs: clay and chips are much cheaper than gas silicate.

“If a person wants to save money on building a house, then he needs to do a lot on his own or with the involvement of volunteers - relatives, friends,” says Yuri Suprinovich. - Then, in fact, the benefit is obvious, since the wages of builders will be practically zero. If you invite a construction company, then the price of a house made of wood chips and clay will not be cheaper, and maybe even more expensive than a traditional house. There is a lot of manual labor during the construction, but it is not cheap.

Knowledge and experience can be obtained completely free of charge. It is enough to be a volunteer in the construction of such houses.

Yuri Suprinovich says that compared to agro-houses, the construction of which was financed by agricultural enterprises, houses using German technology were somewhat cheaper. And this is without saving on the quality of finishing and the level of equipment with internal engineering systems. For example, a house for living in 130 square meters in Old Lepel cost about 50 thousand dollars (without landscaping the adjacent territory).

Energy prices, alas, do not show a downward trend, therefore, in the construction of housing, the issues of truly effective thermal insulation of houses always come to the fore. There are many different technologies for insulating buildings using facade or materials placed inside, using special hinged structures, etc. However, many issues are resolved already at the construction stage, if building materials with their own high thermal insulation qualities are used for the construction of walls. One of these materials is wood concrete, or, as it is more often called, wood concrete.

Once widely used in construction, over time it was undeservedly forgotten, and many potential developers sometimes do not even know anything about it. However, wood concrete began to restore its position of demand, began to appear in the sale. But if you can't buy it, you shouldn't despair - there is always the opportunity to make wood concrete blocks with your own hands.

What is wood concrete, and what are its main advantages

The material, which is commonly called arbolite, consists of two main ingredients. Its main mass is a filler made of wood chips and sawdust, which are interconnected by the second fraction - Portland cement. The total mass may include special chemical additives that improve the quality of wood or increase the plasticity of the resulting mixture, but their specific amount is very low.

It is not necessary to assume that such wood concrete is some kind of novelty in the family of building materials. On the contrary, the use of plant components with mineral binders has a long history - how can you not recall the ancient technology of adobe construction, where the main ingredients are straw and clay. With the development of silicate production, when the production of cement began on a mass scale, the first experiments with wood concrete began to be carried out.

In the 50s - 60s of the twentieth century, wood concrete began to be produced on an industrial scale. The material has passed comprehensive tests, received the appropriate GOST, was constantly modified - several research teams worked on this issue. A striking proof of the quality of the building material produced is the fact that it was from wood concrete that several buildings were erected at Antarctic stations, including the building of the dining room and kitchen. The calculation justified itself - it was not difficult to deliver such a light material over a huge distance, and the walls, only 30 cm thick, maintained a comfortable mode in these extreme conditions.

Unfortunately, in the future, the main emphasis in the industrial production of building materials was placed on reinforced concrete, the problems of energy conservation and ecology were then of little concern to anyone, and arbolite was undeservedly simply forgotten. A sufficiently wide network of enterprises for its production ceased to exist, no developments in this direction were carried out.

Nowadays there is a "reanimation" of this direction of production of wall materials. Arbolite began to be used again in construction, the demand for it increased. Many private entrepreneurs are engaged in the production of wood concrete - machine-building enterprises have even set up the production of special mini-lines. Adhering to certain technologies, it is quite possible to make wood concrete blocks with your own hands and at home.

What wonderful qualities this material has, and what benefits it gives from its use:

The first thing that is always paid attention to is excellent thermal insulation characteristics. The wood is "warm" by itself, plus the "airiness" of the wood concrete plays an important role. Let's compare - only 300 - 400 mm of wood-concrete masonry is as effective against cold as a brick wall about 2 meters thick!

Arbolit is an excellent sound insulator. The house built from it will not penetrate street noises.

The material is light - its density is from 400 to 850 kg / m³. And this is a reduction in the cost of transportation, construction (no special lifting equipment is needed), a decrease in loads on the base of the building, and there is an opportunity to use a simpler and more inexpensive foundation.
The lightness of wood concrete does not mean its fragility at all. On the contrary, it has enviable ductility and shock-absorbing qualities (compression - up to 10% of the volume) with good bending strength. Under loads, it will not crack or crumble, and after removing the effort, it tries to restore its previous shape - the reinforcing effect of wood chips affects. Strong accented blows that destroy other wall materials are limited to the washed surface, but without disrupting the overall structure of the block.

This is especially important when erecting buildings on problem soils or in regions with increased seismic activity - the walls of the house will not crack.

Arbolite is an environmentally friendly material. With proper pre-treatment of raw materials, it will not become a breeding ground for microorganisms, mold, insects or rodents. In it, the processes of debate and decay of the material do not occur with the release of substances harmful to human health. At the same time, it has excellent vapor permeability, the walls are able to "breathe", condensation does not accumulate in them.
The material is practically non-combustible, despite the high component content of wood. At critically high temperatures, it retains its given shape much longer than other insulation blocks based on polymers.
Arbolite walls lend themselves easily to any kind of exterior finish, showing excellent adhesion with most of the mortars and mixtures used, even without the use of additional reinforcing meshes.
The plasticity of the starting material allows you to form building blocks of almost any, even the most bizarre configuration, which opens up a wide scope for architectural design.

One of the important advantages is the simplicity of processing wood concrete blocks. They are easy to cut even with an ordinary saw, they can be precisely adjusted to the required size during construction. In addition, in the walls of this material it is easy to drill a hole of any diameter, self-tapping screws are perfectly screwed into them and hammered nails are held in place.

Video: positive qualities of wood concrete

"Basics" of wood concrete production technology

First of all, you need to make a reservation that everything that has been said above and what will be discussed in the future refers specifically to arbolit, that is, wood concrete. The fact is that sawdust concrete is often presented under the same term (made from fine sawdust with the addition of sand), but there are more differences between these materials than similarities.

Wood chips obtained by crushing wood are used for the production of wood concrete. At the exit from the crushing machine, fragments are obtained with a length of 15–20 mm, a width of about 10 and a thickness of 2–3 mm. In industrial conditions, this is performed by special installations that quickly process non-marketable wood - branches, slabs, tops of cut trees, waste from woodworking enterprises.

By the way, not all types of wood are suitable for the production of wood concrete. Basically, these are, of course, conifers - pine, fir, spruce, but larch is not used for these purposes. Good material is also obtained from individual hardwoods - poplar, aspen, birch. Beech waste cannot be used for wood concrete.

The resulting wood pulp undergoes a special chemical treatment without fail. The structure of wood contains a lot of water-soluble substances of the group of sugars, which not only reduce the performance of the material itself and significantly lengthen the time for complete cement setting, but can also cause fermentation processes in the thickness of ready-made blocks. This can result in the formation of voids, swelling of the surface and other negative consequences.

The neutralization of these substances is carried out with solutions of calcium chloride, aluminum sulphate or "liquid glass" in a certain proportion. In addition, to prevent the development of various forms of biological life in the thickness of the material, wood chips are processed.

The next stage of production is mixing the shaving mass with a binder component - Portland cement; its specific gravity is approximately 10 to 15%. Plasticizers can be added, but not more than 1% by weight.
The resulting plastic mass enters the molding section. The technology can be different - pressing or compaction on a vibration stand, depending on the intended purpose of the resulting products.

After complete filling forms, they are transferred to the drying area, where a certain temperature and humidity regime is maintained. Then the molds are removed (stripping), and the resulting blocks are dried in flowingnot 2 days at a temperature of about 60 ºС.
If necessary, finished products undergo mechanical revision and then go to the warehouse for packaging and shipment to consumers.

The percentage composition of the components is not a clearly indicated value - it can vary in certain limits depending on specific products and their intended use.

In the production of large-sized parts, their additional reinforcement can be used, including with the installation of embedded technological plates and rigging loops.

Arbolite produced in industrial conditions (you can find the names "urmalit", "timfort", "woodstone", "dyurizol" - they slightly differ among themselves in the percentage of additional polymer components) is subdivided into structural and thermal insulation:

The density of structural wood concrete reaches 850 kg / m³, surface strength is about M-50, thermal insulation properties are not too high - thermal conductivity 0.14 - 0.17 W / (m × ° WITH).
Thermal insulating wood concrete has a different picture - the density is up to 500 kg / m³, the strength indicator is within M-5 ÷ M-15, but the thermal conductivity is very low - 0.08 ÷ 0.1 W / (m × ° WITH).

How to make wood concrete blocks yourself

The number of mini-enterprises for the production of wood concrete blocks is growing (for some craftsmen-entrepreneurs, this is becoming a very profitable business), and the material is increasingly found on the free market. But home craftsmen who always try to do everything on their own will never run out.

What is needed for the manufacture of wood concrete construction parts:

First of all, the most important material is needed - wood chips. It is clear that you need a lot of it - it just doesn't make sense to start a process because of several blocks. It is good if there are woodworking workshops nearby, where you can negotiate an inexpensive purchase of such waste. Self-preparation of wood chips on a large scale is a very difficult task, unless, of course, there is a special crusher on the farm. Craftsmen find original solutions by constructing such installations on their own.

Video: homemade wood crushing machine

It will definitely be required - manually preparing a significant amount of high-quality wood-cement mixture will not work.
The required number of forms is prepared in advance. They can be made of wood (boards, thick plywood or OSB), and it is better if they are collapsible - the process of stripping will be much easier. Usually they make a long form with jumpers so that several blocks can be made in it at once. To prevent the mortar from sticking to the wooden surface, the inner walls can be sheathed with old linoleum.

Another approach is a welded or also demountable sheet metal structure with cells of blocks of a certain configuration and size. If desired, you can purchase or order factory molds, often even with devices for molding and pressing - they will make it possible to manufacture blocks of complex configuration, including hollow ones.

To compact the green mass in the molds, prepare a rammer. You can also apply the vibrocompression technique. The easiest way is to use a perforator for this purpose with the transmission of its vibration to a stand with a spring-loaded surface. Another method is the manufacture of a stand with an electric motor installed on it, on the rotor of which an eccentric flywheel is installed.

Certain chemicals may be needed to process wood - we will talk about them a little later.
It is required to prepare an area under a canopy to accommodate filled forms and manufactured blocks for the drying cycle.

In what sequence is the work on the manufacture of wood concrete blocks carried out:

1. Prepare wood pulp. It must be cleaned of dirt, earth, and debris. The total volumetric content of side components (bark, needles or leaves) should not exceed 5%.

Excellent pretreatment for wood chips - calcium chloride

Wood chips must be freed from dissolved sugars. The easiest way is to endure her outdoors, stirring occasionally. However, this will take a lot of time - about 3 months. To speed up the process, it is better to treat it with a 1.5% solution of technical calcium chloride at the rate of 200 liters of solution per 1 m³ of wood. Maintain the mass in this state for up to 3 days with regular daily stirring. However, remember that this method is only suitable for softwoods.

Another method is treatment with "liquid glass", but it should be carried out already when mixing the solution, since silicate components can lead to sintering of the chip mass. And here there is a nuance - "liquid glass" can be used with any type of wood, but it will significantly reduce the plasticity of the resulting blocks, increase their fragility.

"Liquid glass" - accelerates the solidification of the solution, but increases the fragility of products

2. Before starting further work, the wood chips should be treated with lime mortar. It must completely neutralize all the chemical components of the tree, plus to this - give it antiseptic properties.

The shavings are soaked in a solution of slaked lime (5 ÷ 10%) for 3 hours. Then it is laid out on a net to allow the water to drain. The raw wood is no longer dried, but is immediately used for further preparation of the working molding mass.

3. Preparing the mixture for molding. For this, chips are first mixed in a concrete mixer with water, with the addition"Liquid glass" (no more than 1% of the total mass of the planned amount of solution). When a semi-liquid slurry is obtained, they begin to add cement (not lower than M-400) and gradually increase the amount of water. The general proportion should be kept within the following limits: 4 parts of water to 3 parts of wood and 3 parts of cement.

Here you should immediately warn against widespread mistakes of novice craftsmen who begin to measure components in volumetric ratio. The proportions given relate exclusively to the mass of the materials introduced into the mixture.

The solution is mixed until completely homogeneous and all possible lumps are broken. As a result, the resulting mass should be plastic, but crumbly enough. When squeezing the lump in the palm of your hand, it must retain its shape without crumbling after the release of the force.

4. The next step is molding. When the mixture is completely ready, the forms must be lightly smeared with liquid cement milk or oil working. Wood-cement mass is laid out in them in stages, in 3-4 passes, with careful compaction of each layer. If there is a shaker, then this will greatly simplify the task. It makes sense for the rammer to pierce the mixture with sharpened fittings several times in order to facilitate the exit of air bubbles.

You can leave a free space of about 20 mm on top and fill it with plaster, leveling the surface with a spatula. This will allow you to get blocks with an already plastered flat side.

One of the sides can be made immediately "plastered"

There is another way to decorate blocks. Pebbles are placed on the bottom of the molds, tiles - whole or in fragments, then they are poured with ordinary dense concrete mortar to a thickness of about 20 mm, and only then the final forming of the block is carried out.

If reinforcement of the block is required, then first a layer of wood concrete is laid, then a reinforcing mesh is installed and a layer of concrete is poured that completely covers it, and again there is a layer of wood concrete on top.

The filled forms are sent to the pre-drying place.

5. A day later, you can carry out stripping or removing the set blocks from the molds. They are laid under a canopy for further drying and hardening. This usually takes two to three weeks, depending on air temperature and humidity.

Video - An example of the production of wood concrete at home

A well-organized process, with a sufficient number of forms and means of "small-scale mechanization", will make it possible to produce up to 80-100 blocks per day with such manual molding. This should fully ensure the uninterrupted construction of a house built from wood concrete.

I will answer your questions out of order, but I will answer everything.

Let's start with the film. It doesn't change whether this film is vapor-permeable or vapor-impermeable. If it is vapor-permeable, then there should be a ventilation gap behind it (towards the street). If not, then moisture remains in the first layer of the reed. And the gap there technologically does not work out in any way. If the film is vapor-proof, then everything is the same - moisture remains in the first layer of the reed. The fact that manufacturers put it there, but at the same time cannot clearly explain either its operation or its properties, suggests that the manufacturers, unfortunately, have not figured out how this design works. Farther. If, as you write, put the film from the inside. Yes, by doing this we will protect the wall from vapors from the room. But this has nothing to do with moisture accumulating in the wall due to the dew point. There are two reasons for moisture in the wall. One is moisture from the room (we can protect it from this with a film). And the second is the moisture arising from the fact that there is a moisture condensation point (dew point) in the wall. This condensation occurs due to the difference in temperature and pressure, and if there is no vacuum in the structure, and there is no vacuum, then this condensation will occur, even when closed from the inside with a film. Even if the wall is "wrapped with foil" both from the outside and from the inside, then there will still be condensation. because there is air inside, and there is a difference in pressure and temperature. Verbose, but I hope she explained.

A vapor-permeable (breathable) wall or a vapor-proof (non-breathable) wall, there really isn't much of a difference. And in terms of ventilation power too. You have seen the figures, the difference is within 15-20% maximum. To be honest, I'm just surprised by the combination of non-breathing walls and clay. And, as I understand it, plastic windows, right? If a house is being built with such walls for reasons of ecology, naturalness, naturalness, then something is not logical for me :-). And if clay with chips is just a way to reduce the cost of construction, then it is logical.

In general, for captives (or membranes), I would not use them at all in this wall.

On the plaster of the wall. I have never seen this reed (straw) mat live. If you've seen how they are plastered, that's fine. In fact, if they are clipped and the fibers are perpendicular to the plaster layer, then it should hold normally. Mineral wool for plastering works is based on the same principle. In ordinary cotton wool, the fibers are parallel to the wall, and in cotton wool for plaster, they are perpendicular, so that the mixture holds better.

Dew point. I consider the thermal conductivity for clay to be 0.1 (rounded up by 0.095), for the reed mat the thermal conductivity to 0.7 (rounded up by 0.065). The dew point is in the second layer of reed (counting from the outside). Therefore, all the more, it cannot be covered with any film. All moisture from there should be weathered freely through the reeds and plaster. In terms of heat, by the way, if we count clay by 0.1, then 300 mm of it is almost enough for Minsk. 300 mm of clay + 10 mm of reed, - with a margin. And 300 mm of clay + 200 mm of reed, - with a large margin. But I would not remove the "unnecessary" from the design, since these are the thermal conductivity coefficients "on paper", and in my life, in my opinion, they have not yet been fully tested.

She seems to have answered everything, ask.