Do-it-yourself construction technology from sawdust concrete. Building a house from sawdust concrete with your own hands The minimum thickness of the supporting wall of sawdust concrete

So, in this article we are building a house from sawdust concrete - the features of this material will be considered in sufficient detail and the installation instructions will be covered in detail.

Let's start with an overview of key issues.

What is sawdust concrete and is it worth making a house out of it

In fact, sawdust concrete (aka wood concrete) is not a new material - it was invented during the Soviet Union, but has not yet been used very widely.

Basically, this concrete is made up of cement, sand, lime and sawdust. It happens in the form of ready-made blocks and in the form of a mixture.

The more sawdust in the composition of such concrete, the better its thermal insulation qualities. However, if there is a lot of sawdust and little sand, then the overall strength of the material decreases - this should always be remembered.

This material is used for the following purposes:

for the construction of load-bearing walls and partitions in low-rise construction;

Please note that due to not very high compressive strength, it is not recommended to use sawdust concrete for the construction of buildings whose height exceeds one floor.
But if you are building a cottage, and you really want to use the material, then it’s better to “cheat” a little - build the first floor from strong stone, and already the second from sawdust concrete.

for erecting fences and gazebos;
for ;
for insulation of foundations and floors.

As for the specific properties of sawdust concrete, there is definitely something to think about.

Advantages:	Flaws:
1. Relatively low price of the material.	1. Not very high. And if it is increased by reducing the amount of sawdust and increasing the proportion of sand, then the thermal insulation advantages are lost.
2. High thermal insulation qualities. In terms of its heat-shielding characteristics, a sawdust concrete wall is equal to a one-meter-thick wall made of brick.	2. The fragility of the blocks. The material is unlikely to withstand strong mechanical shocks - it will simply crack.
3. The material is easy to work with due to its light weight. And the finished blocks can be sawn with an ordinary hacksaw for wood.	3. High level of moisture absorption. But this is easy to fix - just do not leave sawdust concrete without an additional protective layer of plaster or putty.
4. Raw materials for self-preparation of concrete are easy to get - sawdust is not a scarce or expensive commodity, you see.	4. It is difficult to make a mixture with the correct proportion of all components on your own. That is, in order to achieve optimal strength of sawdust concrete and normal thermal insulation qualities, you need to know exactly how much to add to the solution.
5. High sanitary and hygienic qualities, due to the presence of lime and sawdust in the solution.
6. Fire resistance. The wood inside the cement-sand mortar does not ignite.
7. Sawdust concrete has a relatively low weight, which makes it possible to make an economical version of the foundation.
8. The material has excellent vapor permeability. That is, simply put, the walls of such a house will “breathe”, and thanks to this, there will always be a comfortable microclimate in the room.

As you can see, the advantages are much greater than the disadvantages. So the conclusion here is very simple - it is quite possible to build small houses from the material. By the way, a sawdust-concrete bath is also quite possible - it’s cheap to build it with your own hands from such a mixture, and the heat inside will be perfectly preserved.

Now let's look at another popular question.

Which is better to use: blocks or monolith

Of course, each technology has its own distinctive features, which are as follows:

Block house:	Monolithic:
1. The good thing is that you can build gradually, slowly - so to speak, when there is time.	1. It is better to pour the monolith as quickly as possible so that there are no junctions of the mixture poured into different time did not turn out to be fragile.
2. Any wall configuration is possible. It does not require any formwork.	2. It is quite difficult to create a complex configuration of the wall line - you have to tinker with the formwork. But on the other hand, the formwork for an ordinary rectangular perimeter is mounted in a matter of hours.
3. Blocks can be stored for a long time.	3. If it is far from the start of construction, then the components for concrete mix better not to buy in advance. Cement can, under the influence of moisture, turn into strong large blocks, and sawdust can rot.
4. Building walls from blocks is not a very fast task. Because it’s impossible to lay a lot of stone at once - you must definitely wait until the mortar dries in the seams of the previous rows.	4. Pouring the mixture into the formwork can be done literally in one day. Everything here, in fact, depends only on the speed of preparation of the solution.

In principle, it turns out that each method is good in its own way. However, experienced craftsmen recommend (if possible, of course) still use the option of pouring walls. At least because there will be no seams between the masonry, which will significantly increase the thermal insulation qualities of the house.

Please note that, in general, it is possible to use blocks without heat loss as a result. Only then such walls will then have to be additionally insulated.
Moreover, it is very desirable to do this with mineral wool - if you use expanded polystyrene, then one of the main advantages of sawdust concrete is lost - vapor permeability.

So, as a good example, we are building a monolithic house from sawdust concrete.

House made of monolithic sawdust concrete

It should be noted that we will consider the shortest and most a simple circuit works, but it is not universal! Specifically, in your situation, there may be a lot of nuances, because of which you will have to do something completely differently than in the instructions published below.

Remember this.

We will not describe the foundation device, because there are many types of this design and which one to use for you is a topic for a separate discussion.

Suppose that in our case this is the most common option - a strip base and we will only analyze how to fill the walls with sawdust concrete.

Installation of formwork and installation of a frame of reinforcement

Walls, in fact, are made very simply - in the same way as from any other concrete.

A reinforcement frame is mounted, formwork panels are installed on both sides of it, and all free space is poured with concrete.

Important!
Try to foresee where in the walls there should be holes for pipes, niches for windows, etc.
If this is not done, then later you will have to get acquainted with such work as cutting reinforced concrete with diamond wheels.

Everything is done in approximately the following order (let's look at the example of assembling one wall):

Reinforcement bars of the required length are cut.
If the metal was not released vertically from the foundation in advance, then it is necessary to drill holes in the concrete and hammer the reinforcement bars into them vertically (to the height of the future wall). The distance between them should be about half a meter. If the foundation is very strong and it is impossible to make holes, then pay attention to such a service as diamond drilling of holes in concrete - in theory, everything can be drilled with a professional tool.
If the reinforcement is installed vertically, then it is necessary to attach transverse horizontal rods to it. So that you get a kind of grid with a cell size of about 50 by 50 cm.

If everything is done, then you can start assembling the formwork. This is done very simply.

On both sides of the previously mounted vertical reinforcement frame, wooden sheets, plywood, for example, must be installed (on edge). In order for the formwork to hold vertically and not fall, it is usually supported with triangular timber racks.

After that, they proceed directly to concrete work.

Filling sawdust concrete

This is just the easiest step.

The mixture is being prepared (or brought on a mixer) and the whole mass is poured into the space between the sheets.

It is very important to prevent the formation of voids. Therefore, you need to try to compact the entire filled mixture very carefully - you can even do this with an ordinary chopper.

In addition, if the pouring does not take place “at a time”, then remember one rule: it is impossible for the “docking” of the frozen concrete and the fresh one to pass vertically. It is better to lay the mixture in horizontal rows - so the walls will be more durable.

In principle, if the walls are filled, then after the mortar has dried and the formwork has been removed, you can proceed with the installation of the roof. It is done in the same way as in any other house.

That's all. Let's summarize.

Conclusion

We briefly figured out how a monolithic sawdust concrete house is built and what this material is. We hope that the general principle of technology is now clear to you and you will be able to apply the knowledge gained in practice. Well, if you want to get acquainted with additional information on this topic, then be sure to watch the video in this article.

Each developer is trying to make sure that the house he builds is as cheap as possible, prefabricated, warm and comfortable for living. One of the materials for building a house, taking into account all the above characteristics, is sawdust concrete.

In fact, sawdust concrete is a sawdust-sand-cement mixture, and its manufacture does not require much experience. You just need to follow a simple process. It is for this reason that this material is very convenient for building with your own hands, both block and monolithic walls.

Both sawdust concrete itself and building a house from it with your own hands have their pros and cons, which we will consider further.

The advantages of building from sawdust concrete with your own hands

For the production and construction of buildings from sawdust concrete with your own hands, the following advantages can be distinguished:

components for production are publicly available, they can be purchased right the day before the start of production of the final material, which is very convenient if you do not have the opportunity to store all the components for a long time;
relatively cheap components, from which the low price of the finished building material follows. It is difficult to talk about the exact price, since it will depend on the cost of all components in a particular region. It can only be said for sure that per cube of the described building material will be 3-4 times lower than that of most other lightweight concretes, especially since the requirements for their production imply a more high-tech process;
high construction speed allows you to "build" a house from scratch in a season (often in 2-3 months) and this is mostly done alone;
buildings can be erected both monolithic and from pre-prepared blocks. Each of the options is convenient in its own way, but the flood technology is still more popular due to the possibility of faster construction, and there is less fuss with the product of blocks. Also, monolithic technology eliminates the formation of cold bridges on the walls;
construction both from pre-prepared blocks and the pouring method excludes materials that could not be lifted, moved or assembled by one man, the same applies to technological processes. Additional labor will be needed to create floors and roofs.

Cons of construction from sawdust concrete

As in any business, do-it-yourself construction, in addition to pluses, is fraught with the following minuses, which, rather, are even just features:

you need to clearly select the composition of sawdust concrete for building a house, since it can be of different density and, accordingly, different bearing capacity and thermal conductivity. Correct calculation will help you to obtain a material with the required load-bearing capacity at the lowest possible thermal conductivity, even for block walls, even for flood walls;
it is necessary to carefully study the technology chosen for the construction of walls, whether it is a block or monolithic version, since due to inexperience you can get very curved walls that will barely carry their own weight, or errors will lead to very difficult wall cladding, it happens;
again, it is necessary to strictly adhere to the technology regarding the introduction of substances that mineralize sawdust into the composition of the material, otherwise the high water absorption of sawdust concrete will significantly reduce the service life of a house built from it and negatively affect the comfort of its operation.

To summarize all of the above, sawdust concrete is almost the best thing you can choose for building a house with your own hands, especially alone. The advantages of both the flood method and the block method are simply undeniable, and the disadvantages can only be conditionally called such, and with the proper approach, they are simply excluded.

Video

Sawdust concrete is a material widely used in monolithic construction before the advent of foam concrete. Today, sawdust concrete is most often used to produce wall blocks, which are suitable for the construction of buildings up to 3 floors high.

This article provides instructions, following which you can make sawdust concrete with your own hands. We will also consider the purpose of the material, its specifications, Advantages and disadvantages.

1.2 Testing sawdust concrete blocks (video)

2 Sawdust concrete production technology

The raw material composition of sawdust concrete consists of 4 components - Portland cement, sawdust, sand and water. Also, lime can be added as an additional binder, but there is no real need for its use. Cement mortar is an alkaline medium, when it enters sawdust, sugary substances are released from the sawdust, which adversely affect the final strength of the material.

To exclude negative processes, sawdust must be pre-treated. The easiest way to do this is to stand the sawdust in the open sun for 2-3 months, however, due to the duration of this method, its use is irrational. The most efficient method is soaking sawdust in lime mortar (concentration 1.5%) for 3-4 days with regular stirring. For a cubic meter of material, it is necessary to use 200 liters of water, in which 2.5 kg of lime is diluted. This treatment also protects the blocks from rotting in high humidity conditions.

The proportions of the mixed components depend on the required density of the manufactured material (the data in the table are indicated based on the preparation of a cubic meter of sawdust concrete):

The amount of water varies between 250-350 l/m 3 of the mixture. The specific choice is made based on the initial moisture content of the sawdust. If the moisture content of the material is 35-50%, then you need to add the maximum amount of water (350 l), it ranges from 50 to 100% - the minimum amount.

There are two sequences for mixing the solution:

Initially, cement is mixed with sand, after which sawdust is added to them and water is poured.
Sawdust is poured with water and cement is added, the mixture is stirred to a homogeneous consistency and sand is added.

Lime is always used last. If the production of sawdust concrete is carried out without special equipment, then it is preferable to use the mixing procedure No. 2 due to its lower labor intensity. Note that it is quite difficult to prepare such a solution using a gravity-type concrete mixer, since the water will flow down the tank, and the sawdust will remain on top. Ideally, you need to use a forced concrete mixer, the cost of which starts from 50 thousand.

Handicraft production can be carried out without any special equipment, preparing a solution in a trough. In this case, it is necessary to mix sand and cement with a shovel, then add and mix sawdust and introduce water. The solution must have such moisture that when compressed in a fist, it does not crack, but also does not drain with water.

With the use of such a solution, a sawdust concrete screed can be poured or monolithic construction can be carried out. If the ultimate goal is to make blocks, then you will need to make molds from sheet metal or plywood.

It makes sense to make the form under standard size wall blocks 390 * 190 * 188 mm, but at the same time its height should be 5 cm higher, which is necessary for tamping the mixture. Also, the form should not have a bottom and side handles should be present. For ramming, a separate metal plate is made corresponding to the dimensions of the mold section.

Block production technology is quite simple. Initially, you need to prepare a site on which the blocks will withstand until completely hardened, all work is carried out on its territory. The mold is filled with sawdust concrete, the lid used as a press presses the mixture, which leads to compaction of the block. Further, the form rises by the handles and the block remains lying on the floor. The product will receive working strength after 2 weeks.

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

DIY manufacturing

Blocks of sawdust concrete can not only be purchased, but also made independently, for this you will need:

organic filler such as sawdust or shavings;
sulfate alumina or lime;
Portland cement M300;
water;
mineral additives, namely: liquid glass, calcium chloride, sodium sulfate and ammonia acid.

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

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

pre-measured shares of sand, cement, lime and filler are mixed;
all prepared mineral additives must be dissolved in a container with water;
the solution that was obtained must be added to the prepared dry mixture;
the whole composition is thoroughly mixed.

It should be noted that the prepared components should not crumble in the hand. If this still happens, you need to add astringents to it and mix everything thoroughly again. The hardening and solidification of the prepared blocks is slow, in order for them to gain their strength, several months must pass.

As a rule, stones of various sizes can be made from this material. To do this, you need to have special forms that have a removable bottom. Then the prepared mixture is poured into them in layers and constantly tamped; after completion of work, everything must be left until completely solidified. Next, the blocks will need to be removed and sent to a place where the sun's rays and moisture do not fall, where they will finally harden and gain the necessary strength.

Manufacturing rules

In order to make high-quality sawdust concrete, you need to follow certain rules:

Sawdust is added to the water only after the binders and dry sand are thoroughly mixed. Moreover, water is poured only in small portions from an irrigation funnel with small holes.
The main thing in adding water is its quantity, since if it is missing, the material will be damaged. And in case of an excessive amount, drying and hardening will not go as it should.
Then you need to check the quality of the substance. If everything was done correctly, then when squeezed in the palm of your hand, the material will not fall apart and will give off light moisture.
After the block has completely hardened, its surface should be well rubbed on all sides with cement or gypsum. Formwork can be removed after 5 days have passed.
In order to increase the service life of walls made of this material, you can replace the plaster with a brick cladding.

Quality

Exists different kinds building materials, which are used for the construction of houses, sawdust concrete is especially distinguished among them, which has its own unique advantages:

this raw material can be classified as lightweight concrete;
the material has fairly good thermal insulation properties;
a wall of such blocks of 40 cm in its thermal conductivity can be easily compared with a brick wall of 1 m;
sound insulation performance is significantly higher than that of standard concrete;
this material is frost-resistant, fire-resistant and vapor-permeable (it can withstand temperatures of 1100-1200 degrees for about 2.5 hours), which is why it belongs to the group of slow-burning substances;
ecologically pure;
among all types of lightweight concrete, it has the lowest thermal conductivity.

Sawdust concrete has all these positive qualities. Reviews of builders indicate that this material also has disadvantages, which include hygroscopicity. Its water absorption is from 8 to 12%. But this shortcoming can be smoothed out. Exterior walls must be overlaid with brick or in another way to finish the facade, thereby protecting the walls from excess moisture.

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

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

Classification

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

1. Usage:

intended for laying internal and external walls;
partition parts are used only for the construction of partitions.

hollow - have through holes, which are formed during the manufacturing process (this is done in order to give the block the necessary performance characteristics);
corpulent - partition or wall parts that do not have internal voids.

3. Dimensions:

in accordance with the above GOST, bricks for laying walls can be of the following sizes: 288x138x138 mm, 288x288x138 mm, 290x190x188 mm, 390x190x188 mm, 90x190x188 mm and 190x190x188 mm;
dimensions of partition parts: 390x90x188 mm, 590x90x188 mm and 190x90x188 mm.

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

Price

Wooden stone, or stone tree, as sawdust concrete is called, is also a fairly cheap material. Sawdust concrete, the price of which is low, is considered the most affordable when compared with other materials. For example, one that has dimensions of 390x190x188 mm, made from sand and screenings, costs approximately 23 rubles on the market. A stone that has the same dimensions, but is already made of sawdust concrete, will cost 3-4 rubles cheaper, and at the same time it is lighter and warmer.

By the way, it can replace 7 bricks (the cost of one is 5-7 rubles). It is easy 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, to build a box of a house 8 by 8 meters, 20,000 bricks will be needed, the owner will have to pay 140 thousand rubles only for stones, the same amount to give to craftsmen for masonry and 40,000 rubles for sand and cement. If you use sawdust concrete, then the price of such a building will vary from 100 to 150 thousand rubles. Agree, a tangible benefit.

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

Manufacturing technology

In order to properly prepare sawdust concrete, the proportions must be observed according to the recipe. All ingredients can be purchased at any building supply store. The basis is chips, or any waste from woodworking enterprises. In order to prepare stones of the M20 brand, 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 manufacture of blocks, wood components must be sifted, and if necessary, further crushed. For sifting, you need a sieve with cells of 10x10 mm. Then the prepared ingredients must be soaked in salts to remove the adverse effect of the sugary substances that make up the wood filler on the cement stone. Also, such impregnation will give the material non-combustible properties and protect against damage by rot and fungi. For these purposes, you can use sodium sulfate, lime, aluminum, sodium, potassium, or

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

In order to determine whether the mixture is ready or not, you need to squeeze it in your hand. Ready can be considered a mixture in the form of an elastic lump without excess moisture. The prepared mass should be laid out in forms and carefully compacted so that excess air is completely released. All this must be done quickly enough, since after 1.5 hours the mixture will already set.

There are no strict requirements for the size and shape of the prepared blocks. The width is most often determined by the size of the wall, and the height remains a multiple of several rows of bricks (taking into account the mortar between them). This will become especially convenient if, at the end, brick lining is applied to sawdust concrete. Feedback from builders suggests that very large blocks should not be made, as they will dry for too long, and the deformation during shrinkage will be significant. In order to avoid such troubles, several holes are made in them. Forms for the manufacture of large stones are prepared single or double.

For blocks small sizes it is best to use molds that can be filled with 4 to 9 stones. For their manufacture, boards with a thickness of 30 mm are most often used, then they are upholstered with tin, plastic wrap, plastic, linoleum or other material whose adhesion with cement will be negligible. Outside, the form is pulled together with U-shaped ties with nuts at the ends. For large structures it is necessary to provide additional screeds or a stiffener.

Reviews

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

Environmental Safety. This material is made only from natural ingredients (sand, sawdust, cement), which ensures its high environmental friendliness.
In terms 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 sawdust concrete house will be warm enough.
Small specific gravity allows you to reduce the cost of transportation and installation of the foundation.
Ease of processing greatly simplifies construction. Such blocks can be sawn, very easy to drill, and it will not be difficult to drive a nail into a sawdust concrete wall in the future.
The material has high bending and tensile strength.

Despite all the advantages, builders can also hear negative reviews about this material. The disadvantages include the following points:

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

How to build a block house

A house made of sawdust concrete in terms of all sanitary and hygienic indicators will have good sound-proofing and heat-shielding qualities. Thanks to the presence a large number air pores that are inside this material, the walls will firmly retain heat and guarantee natural ventilation of the premises, thereby maintaining optimal humidity.

From sawdust concrete, it turns out to be quite budget-friendly construction of a house (the price of the material was discussed by us above). In addition, blocks, in addition to what can be purchased at any hardware store, are easy to make on your own. You need to know that this material must be prepared in advance for laying if you did it yourself. To do this, it should be dried for several months.

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

As we said above, sawdust concrete is characterized by increased moisture capacity. Therefore, after construction, the walls must be plastered, but this is best done after complete shrinkage (this process will take approximately 8 months).

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

A large number of craftsmen use sawdust concrete for their work. Reviews of builders about this material are very good and will be useful if you are going to make it yourself. In order to produce high-quality blocks, it is necessary to take into account a number of recommendations:

for thorough drying 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 must be well compacted; for this purpose, builders often use a manual rammer;
it is better to dry the prepared blocks in drafts, due to this, the solidification time will be reduced;
you must not forget that it can rain, if there is no canopy, polyethylene should be prepared in order to have time to cover the material in case of bad weather.

In order to find out how durable the material turned out, you can conduct a test. To do this, the prepared block is dropped from a height of 1 m, if it remains intact, it means that it is of good quality.

Construction of a monolithic house

Today, rapid construction is considered very fashionable and convenient. Masters often use monolithic sawdust concrete. For the construction of this type, it is necessary to lay two layers of roofing felt waterproofing over the foundation. In the case of a low plinth, several rows of brickwork must be completed. Then the formwork is mounted, the material for which can be steel sheets, lumber, moisture-resistant plywood.

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

At the end of the pouring, the 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 fix the crate during cladding.

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

After the pouring is completed, a belt of timber is laid out on top, which will later 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 lined.

It won't cost much 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 built from this material will not require insulation, and masonry of 40 cm will provide protection from frost even at -35 degrees.

The sawdust concrete used in the construction of houses is commonly called a type of wood concrete. The building material was created a long time ago, but real popularity has come to it only now. Sawdust concrete is a type of wood concrete, a building material made from sawdust and chip residues, cement, chalk, sand, clay, etc. For the first time, sawdust concrete was used more than half a century ago, but it became really popular against the backdrop of the construction boom of the “zero” years. The material is widely used in construction country houses and utility rooms.

The peculiarity of sawdust concrete is that everyone can work with it. Build a barn or country house with the help of sawdust concrete blocks, even people without serious building experience can. Working with the material does not require special knowledge, skills, use of complex tools and equipment.

Sawdust concrete has many advantages, but the highest level of heat capacity is considered the main one. Having built outer wall 300 mm thick, you can be sure that the house will be warm. However, experts still recommend using a profile with a thickness of 400-500 mm.

Sawdust concrete is a fairly durable material with good resistance to mechanical stress. The strength of sawdust concrete makes it possible to build structures from it with a height of 2, and even 3 floors.

When building houses, two main methods are used:

production of sawdust concrete blocks and construction of the building using the block method;
application of the technique of monolithic construction using different types formwork.

Both methods involve the preparation of a concrete-sawdust mixture using the same technology.

Video instruction: how is sawdust concrete prepared?

Another huge plus of sawdust concrete is the ease of preparation of the parent composition. Both a summer resident and a novice builder can make a mixture. The main thing is to have a sufficient amount of feedstock and equipment for effective mixing of the composition. To prepare the mixture you will need:

a metal, plastic or wooden container of large volume (it is in it that the solution will be mixed);
a mixer for construction or a stroyperforator with a nozzle designed for efficient mixing;
mixture ingredients: cement, sand, sawdust, chalk, water, lime, etc.

An excellent assistant in the preparation of the solution will be a construction concrete mixer. To determine the correct proportions of the mixture, you can use construction scales, or you can get by with a table that approximately determines the amount of ingredients needed:

Sawdust concrete grade M5 with a density of 500 kg / m³: for 80 buckets of sawdust, 4.5 buckets of cement M400, 3 buckets of sand, 14 buckets of clay or lime.
Grade M10 650 kg/m³: 80; 9.5; 12; 10.5.
Grade M15 800 kg/m³: 80; 13.5; 21; 7.
Grade M20 950 kg/m³: 80; eighteen; thirty; 35.

Please note: in the above table, the amount of sawdust is unchanged, and the amount of other components of the building mixture depends on the brand of sawdust concrete. In turn, the brand is determined by the density of the material.

Its building qualities depend on the density of sawdust concrete. For example, M5 sawdust concrete is an excellent heat insulator, but its strength is low. For the construction of walls, material of higher grades is required, with a much higher content of cement. Based on the table, you can calculate the approximate amount of ingredients per 1 cubic meter of sawdust concrete.

The manufacture of concrete-sawdust mixture requires compliance with a certain technology. First, in two containers, you need to prepare two solutions:

dry mix: sawdust, cement, sand; mix all components thoroughly;
dissolve clay and lime in water.

At this stage, you can do without a concrete mixer by mixing the ingredients of the mixture with a shovel. Nevertheless, you will have to try, because the mass must be homogeneous and plastic. A high-quality mixture is quite dense, it does not spread, but at the same time, when compressed, it does not fall apart into pieces. To achieve optimal density and strength, you can add table salt, calcium nitrate, or some water glass to the mixture. By the way, these ingredients will increase the resistance of the finished material to the effects of fungus and mold. For block sawdust concrete, the same proportions are used as for monolithic.

Which is better: monolith or blocks?

The plastic mortar fits well, so it can be used both for creating walls from block fragments and for a solid concrete structure. But which way is better? When choosing building technology must take into account the most different factors because each has its pros and cons.

Let's look at the aesthetic side first. Buildings from blocks look much more interesting than monolithic ones. The fact is that the monolith requires the movement of the formwork and it will not work to create absolutely even horizontals. Blocks can be folded even and beautiful walls. The only exception is fixed-type formwork made of expanded polystyrene. The use of such formwork is the key to building a beautiful house.

In addition, sawdust concrete blocks are more convenient to install. The builder simply assembles them like a constructor. Manufacture of a monolithic structure - complex technological process requiring certain skills and knowledge.

The disadvantage of blocks is the complexity and duration of their creation. It takes much more time to create sawdust concrete blocks than when making blocks from concrete or slag. Unlike other building materials, sawdust concrete takes months to reach the required strength. The standard drying time for blocks is 3.5 months.

If you decide to build a building from sawdust concrete blocks own production, building material will have to be prepared in advance.

Additional thermal insulation of the blocks will give voids. In addition, this will reduce the amount of material spent on the manufacture of each particular block.

In monolithic construction, the use of sawdust concrete has one serious problem: the formwork will have to be constantly moved, since the mass solidifies quickly enough and after that its movement becomes problematic.

The key disadvantage of both block and monolithic construction methods from plico concrete is that the material is hygroscopic, it strongly absorbs water. The outer walls will have to be carefully finished, completely protecting the sawdust concrete base from moisture. During construction, blocks or mortar for the monolith must be kept under an awning, protected from rain.

Folk builder Andryukha: House made of sawdust concrete

Construction features and pitfalls

Sawdust concrete is a rather specific material, therefore, when building a house from it, it is necessary to follow certain rules, to act in full accordance with the recommendations of experienced builders. Even a slight deviation from the recipe or violation of features construction works may reduce the quality of the final structure.

On forums on the Internet, you can often find discussions about whether it is possible to use sawdust concrete for building a foundation. The answer is unequivocal: of course not! The base is built of concrete, stone, brick. There are also metal pile foundations.

V in general terms, the construction of a house from sawdust concrete has the following features:

The base must be raised above the ground in such a way that the water contained in the soil does not reach the walls of the building; foundation waterproofing should be carried out with all responsibility.
A prerequisite for building quality home from sawdust concrete is the reinforcement of corners; it will not be superfluous to reinforce the walls. The best option it is considered the installation in the corner parts of the house of protective "casings" made of concrete or wood.
Openings of doors and windows must not be left open: they must be enclosed in a reinforcing cage, placing jumpers on top.
If the outer walls are erected using a frameless method, an upper trim is required in the form of a monolithic concrete belt with the addition of metal reinforcement. The belt will relieve the load of the roof on the sawdust-concrete structure. If a frame construction technique is used, then sawdust concrete acts as a filler between the racks. In this case, it is necessary to build a harness from a bar.
The roof of the house made of sawdust concrete also has its own characteristics. Overhangs should be wide: this is necessary to protect the walls from moisture. It is very important to build a thoughtful drainage system with water flowing into a reliable drainage or storm drain. It is impossible for water to collect under the walls of the house.
Sawdust-based concrete structures require strong external protection. The hygroscopicity of the building material can cause serious trouble, so the top coat must be continuous and completely waterproof.

Watch the video: how to rearrange the formwork. The house is looming!

Pros and cons of sawdust concrete

Sawdust concrete is a rather unusual building material with a large number of advantages. However, it also has disadvantages, and they are no less than advantages. To decide what is more significant, everyone will have to independently and taking into account the specific construction situation.

Let's talk about the pros first. The key advantage of the material is its low cost. A sawdust concrete wall will cost much less than a brick or cinder block wall. Laying sawdust concrete blocks is as easy as other piece building materials.

Another serious plus of sawdust concrete is the ability to use it not only for the construction of block walls, but also for the construction of monoliths. A house made of this material is close to a wooden frame in its microclimate - it is, as they say, breathable. In the summer season it is cool in the house made of sawdust concrete, in the winter cold it is warm. Sawdust "delays" sounds, providing excellent sound insulation.

As for the disadvantages, the main and most serious is the increased hygroscopicity of the material. Sawdust easily draws in water, so the walls will have to be insulated. The material does not differ in high strength either: the maximum number of storeys of houses made of sawdust concrete is 3. The durability of the walls also leaves much to be desired, especially in comparison with walls made of brick, concrete, cinder blocks. Strong hygroscopicity leads to the need for a complex and rather expensive finish, which is also a big minus.

When working with sawdust concrete, certain points must be taken into account, and even a slight deviation from the technology will lead to problems in operation.

Sawdust concrete belongs to the category universal materials. The initial consistency is quite liquid, so blocks of any shape can be formed from it, monoliths can be built. This versatility allows builders to save a lot of money.

Watch the video online: block test

The cost of construction from sawdust concrete

Sawdust concrete is sometimes called "wooden stone". Of all the available building materials, it is the cheapest and most affordable. So, blocks for a wall measuring 390x190x188 mm will cost about 230 rubles. One sawdust-concrete stone replaces 7 bricks (the cost of each brick is about 6 rubles).

It will take 20 thousand bricks to build a box of an 8 × 8 m house: this is about 120 thousand rubles. In addition, you will have to purchase cement for 30-40 thousand rubles. A similar building made of sawdust concrete will cost about 100-120 thousand rubles. excluding cement. The savings are significant.

Watch the video: material costs

Construction of a monolithic house

Monolithic construction is convenient and fast. Recently, this technology has been used extremely widely. Used in monolithic construction and sawdust concrete. Before erecting a building, it is necessary to carefully waterproof the foundation with two layers of roofing material.

If the foundation is low, it must be raised brickwork. After that, formwork made of wood, plywood, metal sheets is installed on the plinth. The height of the formwork panels is approximately 60 cm.

Simultaneously with the pouring of the first layers of sawdust concrete, on both sides of the foundation, wooden or metal posts are driven into the ground with a height of the entire proposed wall. The columns are connected with bars, pulled together with wire. After completion of the pouring, the stakes cannot be removed; they will be needed to secure the shields when reinstalling the formwork. In addition, with the help of these stakes it will be possible to fix the crate during facing work.

The sawdust concrete mixture is poured in layers no more than 15 cm thick. Each layer is compacted with a special device. For one construction day, you can pour no more than 30 cm of material, that is, no more than 2 approaches. This is followed by a week break. Every 40 cm of height, the walls are reinforced longitudinally. As reinforcement, use a chain-link mesh or wooden slats. A "belt" of timber or brick is mounted on the finished filler structure. The "belt" serves as a support for the roof.

The moisture protection of the walls is of great importance. The builder will have to clad the facade with high quality. made with wide overhangs. Nevertheless, the cost of building a house from sawdust concrete will pleasantly surprise you: they are significantly lower than in traditional construction. The building, unlike brick and concrete structures, does not require additional insulation: 40-centimeter masonry can easily withstand 35-degree frosts.

Watch the video: how to assemble a formwork frame for pouring sawdust concrete

Building a house from blocks

If a house of sawdust concrete blocks is built in accordance with all the rules of GOST, it will have excellent heat and sound protection. The material contains many air bubbles that retain heat, allow air to pass through, and regulate humidity. According to their technical performance, houses made of sawdust concrete are close to houses made of timber or logs.

Construction belongs to the budget category (we talked about material prices above). Blocks can be made independently, but it is better, of course, to purchase ready-made ones. Sawdust concrete of different grades is sold in all hardware stores.

If you chose independent production blocks, the material must be prepared in advance for work. The basis of this preparation is drying. It is necessary to dry sawdust concrete for a long time and carefully.

In private construction, blocks of various sizes are used. The walls are light, thermally insulated and quite durable. If all technologies are followed, a construction made of sawdust concrete will last for many decades.

Despite the fact that the blocks are similar in structure to bricks and do not seem hygroscopic, it must be taken into account: the material is afraid of moisture. Walls must be plastered. These works are carried out after the final shrinkage of the house, that is, 7-8 months after the completion of construction.

If you decide to build a bath from sawdust concrete, the walls must be waterproofed especially carefully, paying maximum attention to corners and joints.

The cost of materials for sawdust concrete