Do-it-yourself excellent floors made of chip and sawdust concrete wood concrete

Expert answers

Alexander Znaika:

Sawdust concrete is obtained as follows. First, the required amount of sand is poured onto a wooden shield, a mixture of cement and lime is added and everything is thoroughly mixed until the mixture becomes homogeneous. Then add the appropriate amount of sawdust and mix again. Continuing to mix, the mass is evenly moistened.

2. For 1 m of sawdust concrete, 250 ... 350 p of water is taken. Bottom line

refers to heavier concretes (M 25), and the upper one to pebble (M 5).

The amount of water is conveniently determined experimentally. It

should be such that, when compressed, the freshly prepared mixture

retained its shape, but did not release water.

3. Sawdust concrete grade 5 can only be used as a heat-insulating material; 10 - for external walls of one-story buildings with an attic, load-bearing internal main walls, leveling layer

nal foundations, under the Mauerlat And tsr. ; 25 for the outer walls of two

storey buildings, bearing internal main walls, as well as for

unheated sawdust is poured with a solution of cement and lime and thoroughly mixed until a homogeneous thick mass is obtained.

The preparation of sawdust concrete by hand is a very laborious process, therefore, if possible, concrete or mortar mixers should be used.

Sawdust concrete can be sawn, processed with an ax and chisel, and you can also drive nails into it.

Fresh sawdust from coniferous wood can be used without pre-treatment, while old sawdust that has lain for a long time, and those that may be exposed to moisture during operation, should be treated with a 10% solution of calcium chloride or lime milk, dried and treated again with a solution liquid glass (1:7) or bituminous emulsion.

I believe that sodium chloride may be used sometimes as well as calcium chloride.

Actually, as I see it, the use of sodium chloride (common salt) is atypical. Lime is usually used. Preparation of raw materials for the manufacture of arbolite mixture. The filler will be woodworking and logging waste - wood chips, shavings, sawdust, etc.

Please note that the wood particles should be small (less than 40x10x5 mm), since the wood swells when in contact with moisture, which can cause the destruction of the wood concrete block. Wood waste before use must be prepared in an appropriate way - either to stand in the air for 3-4 months, or to process with a solution of lime

Lime mortar is prepared in the following proportions: 2.5 kg of lime and 150-200 liters of water for each cubic meter of filler. After processing, wood waste is kept for three days, stirring every day.

Chemical additives are used in a variety of ways. Many people add slaked lime (from 2 to 4% of the amount of Portland cement).

In addition, excellent additives are: calcium chloride, aluminum chloride, aluminum sulfate. They also need to be used in the amount of 2-4%. For example, 1% calcium chloride and 1% aluminum sulfate. You can also add liquid glass (8-10 kg per 1 cubic meter of wood concrete), and some mineral fertilizers. or here is the same link: (click on Proceed to this site.)

Nicholas:

here is an interesting article about arbolite blocks

nesmetnoe /stroitelstvo/stroim-dom/71-arbolitovye-bloki

cons calculation production photo

SUPERPUPER MAN VASICHKIN:

In what language did you piss it off right now?

Triple Breathable:

The thermal conductivity of materials is very low ...

Chelovek:

Due to the large porosity, friability.

Advantages and disadvantages

Wood concrete has a huge number of advantages compared to other building materials.

• Environmental friendliness of raw materials. It is made mainly from natural ingredients.
• High fire resistance.Despite the fact that wood concrete mainly consists of wood waste, it is not combustible.
• Good vapor permeability. This property allows buildings to breathe and maintain their microclimate.
• Small weight of woodblocks. This factor greatly simplifies construction.
• Easy processing with cutting tools. The block can be easily given any desired shape.

• Ease of handling. When laying wood concrete blocks do not require professional skills.
• Resistant to mold, fungus and pests. The material has IV class of biostability.
• High thermal conductivity. For this reason, wood concrete is often used in the construction of private houses.
• Shrinkage resistance. Walls and partitions in this case will not crack.
• High sound absorption. Thanks to this, the material can also be used for the construction of industrial buildings.
• Resistance to seismic activity.

The disadvantages include the following factors.

• If measures are not taken to protect against moisture, the wood concrete quickly begins to decompose, losing its properties.
• The blocks do not have a perfectly flat surface due to the characteristic features of the composition.
• Arbolite walls require additional finishing.
• The material has a low level of adhesion with plaster mixtures.
• Due to the huge number of handicraft industries, low-quality goods are often found on the market.
• Poor range of products.
• The lack of large-scale production affects the high price of the material and the difficulties with delivery.

The composition of the blocks

For the manufacture of wood concrete, wood waste, as a rule, is taken from conifers - they are less susceptible to biological destruction. As a binder, cement is used (sometimes, to reduce the cost, part of it is replaced with clay and lime). There are a lot of recipes, but as a rule, they take the amount of cement with water equal in weight to the weight of dry aggregate.

To increase the strength of chip concrete, sand is added to it, but one should take into account the fact that with an increase in the amount of sand, the weight of the wood concrete increases and its thermal insulation properties decrease.

Even the composition of chipped concrete (and other materials with wood waste) necessarily includes special salts that make wood waste non-combustible, and they are practically not affected by fungi and bacteria.

Nuances

Before filling wooden molds with sawdust-concrete mixture, they are placed on flat plastic or steel pallets sprinkled with a thin layer of sawdust. Then, inside the cells, wooden plugs wrapped with roofing paper are installed, which are necessary to obtain a hole in the blocks.

When the mixture is laid in a mold, it is rammed with a special rammer. Over the next 3-5 days, the material acquires from 30 to 40 percent of brand strength. After this period, the casting mold is dismantled, and the plugs are removed from the blocks. Ready, but not yet dried products are left in the same place for 3-4 days. During this time, their strength increases already up to 60-70 percent.

Arbolit

Often, sawdust concrete is confused with another building material - wood concrete, which is completely wrong. According to GOST, wood concrete is defined as concrete on a cement binder, chemical additives and organic solvents. However, in the classic version, arbolite concrete involves the use of wood chips. It is she who determines its unique properties.

Exactly, like sawdust concrete, wood concrete is an environmentally friendly wall material, characterized by high rates of fire resistance and thermal insulation. Nevertheless, these two materials, despite the similarity of the structure, have a fundamental difference. The fact is that in the production of wood concrete, instead of small sawdust, which cannot have sufficient strength properties on their own, they use special wood chips, the size of which is strictly normalized.Sawdust, unlike wood chips, cannot sufficiently reinforce (reinforce) the wall block and give it "plasticity". Thus, arbolite concrete is stronger than sawdust concrete in terms of bending strength and ability to temporal deformation without complete destruction. In fairness, it should be noted that sawdust concrete surpasses other types of lightweight concrete in this indicator.

To strengthen the blocks, fill voids and reduce shrinkage, a lot of sand is added to sawdust concrete, and a lot of lime or clay is also used to save binder material. The use of a large amount of sand negatively affects the fire resistance of the material we are considering - at a temperature of +573 ° C, sawdust concrete changes in volume, which can lead to cracking. In addition, due to the significant content of sand, the structural characteristics of the blocks are reduced. So, in order for sawdust concrete to reach the strength of the M25 grade, its density should be 950 kg / m3. Due to the high density, the cost of the material and its delivery increases, and the construction work becomes more complicated.

For wood concrete of a similar brand, the density is from 500 to 700 kg / m3. Considering that with an increase in specific gravity, the heat-saving properties decrease, the thermal conductivity of sawdust concrete and wood concrete differs by more than two times in favor of the latter. This difference is due to the low amount of wood in sawdust concrete compared to wood concrete: about 50% versus 80-90% wood chips. This negatively affects such a property as providing passive ventilation of the room. Here, again, it is worth noting that in this parameter, sawdust concrete is significantly superior to most of the wall materials. It is great for the construction of low-rise buildings and is second only to its "rival".

Thus, it is extremely incorrect to call sawdust concrete arbolite, since these are completely different materials. The only similarity between them is the presence of a wood component in the composition.

Production technology

Today, several methods are used for the manufacture of wall blocks for exterior and interior walls. Most often they are produced by direct pressing or with the help of vibrocasting (vibrocompression).

The first method is a relatively young and fairly budget technology. It provides for daily exposure of wood concrete in forms. But the resulting mass is not homogeneous, which threatens with internal stresses in the finished product.

However, the basic manufacturing process in both methods is the same.

It consists of three important steps.

1. Sorting and crushing of organic matter.
2. Mixing chips with chemical components, cement and water. The operation takes 10 minutes.
3. Forming and drying the finished solution.

Types of blocks with wood fillers

More chip concrete or wood concrete can be divided into the following types:

• heat-insulating. Density up to 450 kg/m3;
• heat-insulating and structural. Density 450-650 kg/m3;
• structural. Density 600-800 kg/m3.

Arbolit and sawdust concrete are used in the form of wall panels, in the form of a monolithic fill and in the form of blocks of various sizes. Features of monolithic pouring are that the wall of wood concrete sets relatively unevenly and warping is possible. And they try not to make blocks more than 20 centimeters in thickness, as they will dry for a long time, and laying heavy blocks is more time consuming.

Another of the distinguishing features of chip concrete is that the walls built from it do not sweat or flow. Since, on the one hand, it retains many of the useful properties of wood, and on the other hand, in comparison with other building materials (brick, foam concrete), it has a higher vapor permeability.

You can even talk about partial displacement ventilation through walls made of wood concrete, sawdust concrete.This is a unique type of ventilation, when air seeps through the structure of the material itself, it heats up, passing through numerous fibers and displacing the already heated “exhaust” air in the house.

Thanks to this, there are no “stagnant zones” in houses made of chipped concrete, the costs of arranging ventilation are significantly reduced (or completely eliminated as unnecessary). And as a result, the heat loss of the house also decreases.

We can sum up:

1. Arbolit (and all blocks with wood fillers) is a material for those who care about their family, and at the same time want to reduce the cost of building a house. After all, wood concrete is 4 times lighter than a brick, which means that you need a not so strong foundation (cheaper).
2. A 35 cm thick chipboard wall corresponds to a brickwork of 1 meter in terms of thermal insulation properties.
3. Reduced ventilation costs.
4. Chip concrete or wood concrete is not subject to damage by rodents, insects, fungi, bacteria and fire, compared to an ordinary wooden house.
5. Due to the porous surface, plaster and putty are perfectly held on the wood concrete.
6. Arbolite is easy to process, it can be easily chopped, sawn, driven in nails and screws.

On heaving and other unstable soils, chip concrete (arbolite, sawdust concrete) is practically indispensable. After all, it has good elastic deformation. And at the slightest movement of the foundation (through frost or movement of the soil), other masonry materials will crack.

And chip concrete can be wrinkled a little, because the chips and chips that make up its composition act as reinforcing fibers on the one hand and on the other hand can be pressed in.

Of the relative shortcomings and features, it should be noted that it is recommended to plaster or brick walls on the outside, or otherwise protect them from direct exposure to precipitation. Also, when making a house from chipboard, you need to make sure that the material is of high quality, because some craftsmen can sell frankly low-quality material, discrediting such excellent material.

Best Answers

I'll be back:

I don’t know the consistency, but you know that the sawdust must be dehydrated and processed by special. composition? and read about brisolite, the same thing ...

Online magazine Tips for hosts:

Sawdust concrete, also known as wood concrete, is a mixture of sawdust, sand, water and cement. Correct consistency? It is not entirely clear what is meant, if the proportions, then it depends on the desired brand. In its simplest form - three buckets of sawdust, a bucket of sand and a bucket of cement. If stronger, two buckets of sawdust, half a bucket of sand and a bucket of cement. In addition, if the sawdust is fresh (up to 2 years old), be sure to add about 5% of the volume of calcium chloride, lime or liquid glass.

If the consistency is in terms of the amount of water, then again from the desired brand, but in general about 0.8 from cement. The fact is that for wood concrete, no matter how much water you add, sawdust will absorb, all one liquid composition will not work. Therefore, you do not need to pour a lot of water. Only strength will decrease. From experience, the composition of something like wet sawdust is obtained, we pile it into the formwork and ram it well. The layer is no more than 20-25 cm. It is best to make a form from boards or sheet metal and prepare blocks, and build from them. But you can also put the formwork from the boards in layers. At the bottom of such formwork we make a support beam. Filled, waited two or three days, rearranged. A beam (20x20 maximum) if done carefully gives a kind of seam, the wall turns out with rustication, quite interesting. As for freezing, here is the question. 40 cm wood concrete, it's like a log 25 -30 cm in terms of thermal conductivity. It will not freeze to death, but the stove will have to be heated.

But in general, wood concrete is afraid of water, so it’s better to veneer on the outside, and you can immediately lay an additional layer of insulation. Well, the number of storeys is no more than two floors ...

Mixing

One of the most time-consuming stages in the production of sawdust concrete (even a novice builder can make blocks with his own hands) is mixing, so it is recommended to use a concrete mixer or at least a mortar mixer. This will make the mixing procedure not only more comfortable, but also of better quality. Before pouring dried sawdust into a concrete mixer, they must be sifted through a sieve with a mesh side of 1 cm. Then sawdust can be mixed with cement. Only after that, clay or lime dough, prepared in advance, is added to the mixture. All components must be thoroughly mixed and diluted with water. Water must be added in small portions. After each topping up, it is necessary to mix the sawdust concrete mixture. The proportions of the components are set individually, depending on the purpose of the final product. The more load will fall on the blocks, the higher their brand.

If sawdust concrete is kneaded properly, then when compressed in a fist, the mixture will form a plastic lump, on which, in the absence of water drops, dents from fingers will be visible. This is considered the main indicators of a properly prepared mixture.

Compound

As the name implies, the defining element of this material is sawdust. In addition, the composition of sawdust concrete includes sand, cement, as well as clay or lime. Due to favorable sanitary and hygienic indicators, the material is optimal for the construction of residential walls.

The density of the building material depends on the ratio of sawdust and sand. The more sand and binders in sawdust concrete, the greater its density. In this case, the material has high strength, but low thermal characteristics. With an increase in the amount of sawdust, the strength decreases. Together with it, the frost resistance of the material and its water resistance decrease, which, in turn, adversely affects the corrosion resistance of steel reinforcement. Reinforcement is used when laying walls. From the foregoing, we can conclude that before you start building a house from sawdust concrete, it is necessary to study the features of the influence of the composition of the material on its properties

When choosing one or another composition, it is worth taking into account the thickness of the walls, the number of storeys of the building and the purpose of the walls (internal, external or load-bearing)

Pros and cons of sawdust concrete

Sawdust concrete is increasingly being chosen to create country houses. Its use can bring certain advantages, since the following positive qualities can be distinguished in the material:

• the load on the foundation is noticeably reduced;
• increased thermal insulation is observed;
• construction cost is lower;
• walls are resistant to frost and do not ignite;
• there is protection against the effects of microorganisms;
• the house has excellent sound insulation;
• you can clad the walls with different materials.

However, like other building materials, sawdust concrete has some disadvantages that must also be taken into account during construction:

• bearing capacity is low;
• blocks are able to absorb moisture;
• it is necessary to clad the walls;
• the material shrinks.

Comparison with other materials

For the erection of a residential building or an outbuilding, it is very important to choose the right building components. But you should know that there are no good or bad materials, there are only suitable and not very good ones.

Expanded clay concrete. As well as wood concrete, it is an environmentally friendly material and belongs to the class of lightweight concrete. It consists of expanded clay (baked clay or shale), cement, sand and water. However, claydite blocks have a thermal conductivity index (0.5 - 0.7 W / m K), that is, slightly worse than that of wood concrete. Therefore, for the house, from the point of view of heat preservation, it is better to choose wood blocks. Despite the higher strength, expanded clay concrete may not withstand excess pressure.This is due to the hollow space inside the product.

• sawdust concrete. In composition, this material is very similar to wood concrete. In both cases, wood waste is used. Just like wood concrete, it is considered an environmentally friendly building material, has high heat-shielding qualities and is resistant to stretching, bending and impact.
• Aerated concrete. The cellular composition consists of sand, cement, water and a blowing agent, due to which the characteristic porosity appears. Unlike wood concrete, the gas block has a clear product geometry. The material is characterized by high water resistance and brittleness. If we compare this material and wood concrete, then aerated concrete wins in many respects.

• Polystyrene concrete. This is a type of lightweight concrete, consisting of Portland cement, expanded polystyrene granules and air-entraining additives. It has high structural strength. It shrinks, but much less than gas blocks and foam blocks. As well as wood concrete, it has good thermal insulation properties. Polystyrene concrete blocks do not need additional insulation.
• Straw blocks. They are a building material consisting of environmentally friendly raw materials - pressed straw. Straw blocks have a better thermal conductivity than arbolite (0.05 - 0.065). But they also have disadvantages such as high moisture absorption and low fire resistance.

• Bar. It is a highly environmentally friendly breathable material made from glued boards or logs. It has excellent thermal conductivity and high strength. It is a worthy competitor to wood concrete.
• Gas silicate. This cellular material is obtained from a solution of fine sand, lime, gas-forming additives and water. It is similar in structure to aerated concrete, but there is a difference in composition and, consequently, in properties. It is characterized by good thermal conductivity, high brittleness and increased moisture absorption.

• Fiberboard. This is an analogue of wood concrete with a very similar composition. In both cases, wood waste is used as a component. But if in the first version there are chips, then the fiberboard uses wood fiber, which is made in the form of thin and narrow tapes. Like wood concrete, it has good thermal conductivity (0.08 - 0.1 W / m K) and needs additional protection from moisture.
• Sibit. It consists of concrete, gypsum, aluminum powder with the addition of surfactants and water. It is considered environmentally friendly materials, as an artificial stone is formed as a result of reactions. It has extremely high frost resistance (up to 250 freeze and thaw cycles), but low fracture strength. For a low-rise building, it is usually not used.
• Adobe. This is the oldest building material, consisting of environmentally friendly raw materials - clay soil and straw. Adobe has an excellent thermal conductivity coefficient (0.1 - 0.4). However, it has an important drawback - increased moisture permeability.

About the pros and cons of wood concrete, in the video below.

Final drying

Drying is the last stage in the production of sawdust concrete. For final drying, the blocks must be moved under a canopy or covered with polyethylene. It is desirable that they be in a draft. When laying the blocks, it is necessary to leave gaps between them for ventilation. As a rule, laying is carried out in the form of pillars. To begin with, a couple of wall blocks are placed on two fired bricks, then a couple more across them, and so on. After a month, the blocks will harden, dry and reach 90% strength. To make them as strong as possible, it is recommended to wait another three months before starting construction. It is up to you to ignore this rule or not, it all depends on the type of building for which the material is being prepared. For example, to build a sauna from sawdust concrete, it is not at all necessary to wait until the products are 100% dry.Fully finished blocks must be solid, strong and free of cracks. When falling from a meter height, they should not break.

Advantages of building a house from sawdust concrete

For each developer, it is important that housing is as cheap as possible, and the speed of construction and getting a warm and comfortable home is also important. It is under such characteristics that sawdust concrete falls

For the construction of buildings, some advantages of the material can be identified:

1. The composition contains components that are publicly available, so they can be easily bought, which is very convenient if there is no warehouse to store a large stock of elements.
2. The components have a low cost, so the price of the finished structure will not be too high. It is not easy to name the exact cost, since the price of components is different in each region. With accuracy, it can only be argued that the amount will be much lower than if other lightweight concretes are used.
3. You can build a house very quickly. Even if the construction starts from scratch, it will be possible to fulfill the plan already in a season.
4. It is possible to erect both monolithic buildings and from blocks prepared in advance. Each of these methods is convenient, but flood technology is gaining more popularity, since the house is being built much faster and there is no fuss with blocks.
5. When building a house in any of the ways, there are no materials that have a lot of weight, so even one person can handle it. Assistants will be needed only when creating floors and constructing a roof.

When building a house from sawdust concrete, there are also disadvantages, which, however, can be considered as features of the material:

It is necessary to correctly select the composition for the construction of the structure, since it can turn out to be of different density, therefore, this will affect the bearing capacity and heat conductivity.
It is important to thoroughly study the technology of the chosen construction option, because due to insufficient experience, the walls can turn out to be curved, barely supporting even their own weight. Such errors will make wall cladding very difficult.
It is necessary to follow the technology for introducing substances of a mineralizing type, otherwise, due to high water absorption, the service life of the building will noticeably decrease, and it will not be very comfortable to operate it .. https://www.youtube.com/embed/KCC1XoEtFq4

To summarize, sawdust concrete is the best choice for building your own home, especially if you do it yourself. There are plenty of advantages for this material, and if the approach is correctly implemented, then there will be no minuses. Moreover, many of the shortcomings are easily eliminated. The facade of the house can be plastered or clapboard can be used for cladding, and the use of other materials is also acceptable. Thus, the house acquires a beautiful appearance. If you make reliable moisture insulation of the walls, then such a house will serve for quite a long time. Sawdust concrete is an excellent option for the construction of small low-rise buildings, especially when it comes to cost savings.