Opilkobeton: reviews of builders. Monolithic walls of sawdust concrete

This material is made of safe, clean and natural components (the composition of sawdust concrete: sand, cement and wood sawdust). Due to the large content of organic filler (chips), such blocks have good sound-absorbing performance and low thermal conductivity. In terms of its parameters, this material is fully consistent with wood and therefore provides a high-quality microclimate in living quarters.

Manufacture by own hands

Blocks of sawdust can not only be purchased, but also manufactured independently, you will need:

• Organic filler, such as wood sawdust or shavings;
• Sulfurous acid or lime;
• Portland cement M300;
• water;
• Mineral additives, namely: liquid glass, calcium chloride, sodium sulfate and ammoniac acid.

Opilkobeton can be distinguished by its composition, technology of preparation, the content of mineral additives and binders. In order to increase strength, sand is most often used.

The preparation of sawdust concrete is carried out according to the following scheme:

• Premixed parts of sand, cement, lime and filler are mixed;
• In a container of water you need to dissolve all the prepared mineral supplements;
• The solution that was obtained should be added to the prepared dry mixture;
• The whole composition is thoroughly mixed.

It is necessary to pay attention, that the prepared components should not be scattered in a hand. If this does happen, add astringent substances to it and mix it thoroughly again. The hardening and solidification of the prepared blocks is slow, in order for them to gain strength, it must take several months.

As a rule, from this material it is possible to make stones of the most different sizes. For this, you need to have special forms that have a removable bottom. Then in them the prepared mixture is poured in layers and it is constantly compacted, after the end of the work it is necessary to leave everything till the complete hardening. Next, you need to take out the blocks and send them to a place where sunlight and moisture do not get there, they will finally solidify and gain the necessary strength.

Production rules

In order to qualitatively make sawdust concrete, you need to follow certain rules:

1. Sawdust is added to the water only after the binding substances and sand are thoroughly mixed in a dry form. And the water is poured only in small portions from the irrigation funnel with small holes.
2. The main thing in the addition of water is its quantity, since if it is missing, the material will be spoiled. And in the case of excessive amounts - drying and hardening will not go well.
3. Then you need to check the quality of the substance. If everything was done correctly, then when compressed in the palm of the material does not fall apart and will give off with light moisture.
4. After the block has completely hardened, its surface must be well ground on all sides with cement or gypsum. Formwork can be removed after 5 days have passed.
5. In order to increase the service life of walls made of this material, it is possible to replace the plaster with a brick lining.

Quality

There are different types of building materials that are used to build houses, among them there is a special emphasis on sawdust concrete, which has its unique advantages:

• This raw material can be classified as lightweight concrete;
• The material has sufficiently good thermal insulation properties;
• The wall of such blocks of 40 cm in terms of its thermal conductivity can easily be compared with a brick wall 1 m thick;
• The sound insulation is much higher than that of standard concrete;
• This material is frost-resistant, fire-resistant and vapor-permeable (it can withstand the impact of temperature 1100-1200 degrees for about 2.5 hours), which is why it is classified as a group of difficultly combustible substances;
• ecologicaly clean;
• Among all types of lightweight concrete it has the lowest thermal conductivity.

All these positive qualities are possessed by sawdust. The feedback from the builders indicates that this material also has drawbacks, which include hygroscopicity. Water absorption in it is from 8 to 12%. But this defect can be smoothened. External walls must necessarily be bricked or otherwise to finish the facade, thereby protecting the walls from getting excess moisture.

Before the production of sawdust concrete, chips must be treated with water-repellent compounds, which will reduce hygroscopicity.

It is important that this material is easily machined, so there will not be a lot of waste during the construction of the walls.

Classification

Like all types of building materials, sawdust blocks should comply with GOST 6133-99. They are systematized according to the following parameters:

1. Use:

• Are intended for laying internal and external walls;
• Partitions are used only for the construction of partitions.

2. Form:

• Hollow - have through holes, which are formed in the manufacturing process (this is done in order to give the unit the necessary performance characteristics);
• Full-body - partitions or wall parts that do not have internal voids.

3. Dimensions:

• In accordance with the above-mentioned GOST, bricks for laying walls can be of the following sizes: 288x138x138 mm, 288x288x138 mm, 290x190x188 mm, 390x190x188 mm, 90x190x188 mm and 190x190x188 mm;
• The sizes of partitions: 390х90х188 mm, 590х90х188 mm and 190х90х188 mm.

It is also possible to manufacture blocks and other necessary sizes.

Cost

A wooden stone, or a stone tree, as the sawdust concrete is called, is also quite cheap material. The sawdust concrete, whose price is low, is considered the most affordable if compared with other materials. For example, one wall block that measures 390х190х188 mm, produced from sand and screening, costs about 23 rubles on the market. The stone, which has the same dimensions, but is already made of sawdust, will cost cheaper by 3-4 rubles, and while it is more light and warm.

By the way, it can replace 7 bricks (the cost of one - 5-7 rubles). It is not difficult to calculate that a wall made of a mixture of sawdust and concrete will cost 2.5 times cheaper than a brick wall. In other words, 20,000 bricks will be needed to build a 8-by-8-meter house box, the landlord will have to pay 140,000 rubles only for stones, give the same amount to masters and 40,000 rubles for sand and cement. If you use sawdust concrete, the price of such a structure will vary from 100 to 150 thousand rubles. Agree, a tangible benefit.

We compare with other materials sawdust: the price for a brick cube will be 3 times higher than the cost of a cinder block, the cube of a natural stone - 2 times, the cinder block - 1.5 times.

Manufacturing technology

In order to properly prepare the sawdust concrete, the proportions must be observed according to the recipe. All ingredients can be purchased at any store for construction. The basis is chips, shavings, sawdust or any waste from woodworking enterprises. In order to prepare stones of M20 grade, it is necessary to take 200 kg of cement, 50 kg of clay or lime, 500 kg of sand and 200 kg of sawdust.

For the production of blocks, wood components must necessarily be sifted, and if necessary, then grind it further. For sieving you will need a sieve with 10x10 mm cells. Then the prepared ingredients must be soaked in salts to remove the adverse effect of the sugars contained in the wood filler on the cement stone. Also, such impregnation will give the material non-combustible properties and protect against damage from rot and fungi. For this purpose, sodium sulfate, lime, calcium chloride, aluminum, sodium, potassium or liquid glass can be used .

Mixing sawdust concrete, the proportions of which were correctly observed, is best in a concrete mixer or in any other similar mixer, since it is difficult to do this by hand. The wood filler is mixed together with cement and sand, then lime (clay) dough is added and again everything is thoroughly mixed. Then in small portions you need to pour in water. Then carefully mix the resulting mass.

In order to determine whether the mixture is ready or not, you need to squeeze it in your hand. Finished can be considered a mixture in the form of an elastic lump without excess moisture. Prepared mass must be decomposed into molds and carefully compacted, so that excess air completely leaves. This all needs to be done quickly enough, since after 1.5 hours the mixture will already grasp.

There are no strict requirements for the sizes and shapes of the blocks being prepared. The width is usually determined by the size of the wall, and the height remains a multiple of several rows of bricks (taking into account the solution between them). This will be especially convenient if in the end there will be a brick lining on sawdust concrete. Feedback from builders suggests that you do not need to make very large blocks, as they will dry too long, and deformation when shrinking will be significant. In order to avoid such troubles, they make several holes. Forms for making large stones prepare single or double.

For blocks of small sizes, it is best to use shapes in which you can pour from 4 to 9 stones. For their production, boards with a thickness of 30 mm are most often used, then they are clamped with tin, plastic film, plastic, linoleum or other material, the adhesion to cement of which will be insignificant. Outside, the form is tightened by U-shaped screeds with nuts at the ends. For large structures it is necessary to provide additional ties or a stiffener.

Reviews

Recently, very often, at construction, such inexpensive and high-quality material as sawdust concrete is used. Feedback from builders who often work with it, confirm its main advantages. These include:

• Environmental Safety. This material is made only from natural components (sand, sawdust, cement), due to this, and its high ecological compatibility.
• According to the parameters of vapor permeability and sound absorption, it can be compared with wood.
• It fully complies with the established sanitary and hygienic standards.
• Due to the low thermal conductivity of the material and the voids that are in it, the house of sawdust concrete will be warm enough.
• A small specific weight makes it possible to reduce the costs of transportation and installation of the foundation.
• Easiness in processing greatly simplifies construction. Such blocks can be sawed, very easy to drill, and also it will not be difficult in the future to drive a nail into a wall of sawdust concrete.
• The material has a high bending and tensile strength.

Despite all the advantages, the builders can also hear negative feedback about this material. The following are the drawbacks:

• Relatively high degree of moisture absorption, which requires the implementation of measures for additional moisture protection.
• There is a need to increase the cement content in the block when building several floors. This can lead to higher costs, deterioration in the quality of insulation and higher requirements for the strength of the foundation.
• There is a relatively high degree of shrinkage, which complicates the work on the finish.

How to build a house from blocks

The house from sawdust concrete on all sanitary-and-hygienic indicators will have good sound-proof and heat-proof qualities. Due to the large number of air pores that are inside this material, the walls will firmly retain heat and ensure the natural ventilation of the premises, thereby maintaining optimum humidity.

From sawdust concrete it turns out to be quite budgetary construction of the house (the price of the material was considered above). In addition, the blocks, in addition to what can be purchased at any construction store, it is easy to manufacture by yourself. You need to know that this material must be prepared in advance for styling, if you did it yourself. To do this, it should be dried for several months.

Recently, private construction has become popular, it uses blocks of various sizes, depending on the needs. Walls from such raw materials will be strong enough, light and low-heat-conducting. If they are properly built, they will last very long.

As we said above, sawdust concrete is characterized by an increased moisture capacity. Therefore, after the construction of the wall must be plastered, but it is best to do this after full shrinkage (this process will take approximately 8 months).

The bath of sawdust concrete, like the house, must be very strong, so the walls must be reinforced with wooden slats or brushwood, which is previously cleaned of the bark. The prepared reinforcement is stacked every 40 cm in several rows. In this case, great attention must be paid to the corners and interfaces of walls.

Useful recommendations for the manufacture of blocks

A large number of masters for their work use sawdust. Feedback from the builders about this material is very good and will be useful if you are going to do it yourself. In order to produce quality blocks, it is necessary to take into account a number of recommendations:

• To carefully dry between them you need to leave gaps;
• Before pouring the material into molds, they are placed on pallets and sprinkled with a thin layer of sawdust;
• The mixture needs to be well compacted, for this purpose builders often use manual ramming;
• Dry the prepared blocks better in drafts, thereby reducing the setting time;
• We must not forget that it can rain, if there is no canopy, you should prepare polyethylene to have time to cover the material in case of bad weather.

In order to find out how strong the material has turned out, it is possible to conduct a test. To do this, the prepared block is reset from a height of 1 m, if it remains intact - that means, it is of good quality.

Erection of a monolithic house

To date, it is considered very fashionable and convenient for rapid construction. Masters often use monolithic sawdust concrete. For the construction of this type it is necessary to lay two layers of waterproofing from the roofing material on top of the foundation. In the case of a low socle, several rows of brickwork must be made. Then the formwork is assembled, the material for which can be steel sheets, lumber, moisture resistant plywood.

The height of the installed shields should be approximately 60 cm. When the first layers are poured on the side of the foundation, stakes are pounded into the soil to the full height of the walls. The selected material for the boards is wedged between the side surfaces of the foundation, and then the pins are joined together by pieces of bars, and those that are located on opposite sides of the wall are pulled together by wire.

At the end of pouring pegs should remain in the walls, then they will be used to fasten the shields during the rearrangement of the formwork, and after the private construction is completed - to secure the lathing at the lining.

The prepared mixture for sawdust concrete is poured in layers, the height of which does not exceed 15 cm, and afterwards it is thoroughly rammed. At one time, the wall can be raised only by 20-30 cm, after you need to take a break for 5-7 days. After every 40 cm it must be reinforced longitudinally by means of wooden rails or steel mesh.

After the pouring is completed, a belt from the bar is laid out on top, which later will serve as a support for the roof elements. It is very important to protect new walls from moisture. To do this, the future roof is made with wide overhangs, and the facade is faced.

It is not very expensive to build a house. The price of sawdust concrete is quite acceptable for the average resident of our country. The building will serve for many years, its walls, erected from this material, will not require thermal insulation, and a masonry of 40 cm will provide protection from frost even at -35 degrees.