The optimal price of a cottage made of lightweight concrete: what can you save on? Comments. How to reduce heat loss through masonry joints

2.1.1. Do-it-yourself erection of a self-supporting wall from aerated concrete blocks Unlike her, self-supporting structure(wall) is not a support,

Production of window blocks The design of window blocks includes binding and a box. Those window blocks, which are intended for installation in showers and toilets, it is advisable to do with one cover. Moreover, in buildings that are not equipped with a heating system, it is best

Erection and waterproofing of walls made of lightweight concrete 1. The wall is erected from ready-made blocks on cement mortar with mandatory dressing of the seams (Fig. 15) or in a monolithic way in a removable formwork from wooden panels. Blocks can also be made construction site,

1. Production of window blocks Production of window blocks with separate covers. For the production of elements of window blocks, it is planned to use lines for cutting lumber, processing bars, cleaning surfaces and processing along the perimeter of edges

2. Production of door units

Lightweight concrete houses

From 10,000 - 15,000 rubles per sq.m. warm circuit

Any size and shape

Investments are determined by the Project

All from lightweight concrete last century built barges, landing stages, ships. They served faithfully for a long time. Today, the good old surface technology is gradually mastering the land "to the maximum." And what is no less interesting, at a modest cost, realizing absolutely fantastic compositional color and pictorial ideas...

See for yourself. Everything ingenious is simple. You are not limited by anything in the choice of colors and shapes.

We “knit” a structure of reinforcement and meshes on the foundation, spray concrete from a pneumatic ladle, taking into account insulation (for insulation, you can use not only “chemical” polystyrene foam, but also materials from the earth - heaters from basalt and fiberglass), mount communications, taking into account heat conservation, we finish, we realize decors of varying degrees of complexity (optional), and the house is ready.

The convenience of light cements lies in the fact that decor work can be carried out after settling into the house in full readiness. If you want to avoid the hassle of decor - use vertical gardening(in our case it is more appropriate to call it "spherical"). Also, you are not limited in creating man-made stones and rocks on your site, on which pines or plums, cherries and other amazing trees beautifully bloom in spring.

As you can see, making any fancy organic shape for your home is easy.

And it's absolutely easier than ever - to make a classic domed house-sphere.

Attention!

Modern grids and fittings are produced along with metal - composite. Meet!

Polymer composite meshes have many advantages over metal ones http://yazk.ru/

Complete absence of corrosion

less thickness,

Low thermal conductivity - 0.46 W / m2, about 100 times less than metal, metal - 40-60 W / m2

The same thermal expansion module as concrete and DSP,

Is a dielectric

non-toxic

Projected durability of at least 80 years,

The cost of equal-strength replacement is cheaper than metal up to 1.5 times.

Examples are shown in the photographs. At will - we build from composite grids and fittings. This is good for ours, to varying degrees depending on the meta of residence, but in general a harsh climate. Concrete is easy to work with. To implement all the most incredible and "luxurious" ideas for decoration and decoration, it is enough grinding machines and resistant inexpensive paints for walls and floors (acrylic or water-based). Similar lightweight concrete allows you to amazingly decorate areas around the house, adding convenient and beautiful elements - garden sculptures, paths, water storage and reservoirs, garden ponds, campfire sites and much more. Among other things, concrete is convenient for imitating wood, natural stones and many other materials.

Recall that houses made of lightweight concrete are distinguished by the highest strength and seismic resistance up to 9 points.

Click to enlarge

3D PANELS FROM FERROCEMENT OWN HANDS

See example instructions for self construction houses of "ordinary" rectangular shape with polystyrene foam padding.

The device of 3D panels and the construction of a house from them with your own hands. Characteristics and work with the material.

Prefabricated energy-saving houses, which are not afraid of cracks and deformations, are built from reinforced panels - meshes filled with polystyrene foam. During installation, the panels are “packed” into a kind of concrete shell. So the walls and ceilings are combined into a monolithic structure with insulation inside, light, but surprisingly strong.

The panel, called 3D by experts, consists of a three-dimensional wire frame and a lightweight core made of expanded polystyrene foam.

The strength of this design is additionally given by transverse diagonal rods welded to the mesh of reinforcement from all sides.

A standard panel measuring 3 by 1.2 meters weighs an average of no more than 20 kilograms.

The weight standard panel(3 x 1.2 m) - only 20 kg.

After mounting the panel, concrete is applied on both sides of it with a special shotcrete method with a layer of at least 5 cm. The total thickness is approximately 25 cm. With this thickness of the panel, sound and heat insulation is equal to brick wall 1.5 m thick (!).

Pros and cons of shotcrete technology and construction from 3D panels

Internal arrangement of 3D panels

Expanded polystyrene was not chosen as the core by chance. This is an environmentally friendly and durable material that provides not only high sound protection and thermal insulation, but also excellent resistance to fire, and hence fire safety. It has a good price-quality ratio and is completely indifferent to moisture. The lightest polystyrene foam "stuffing" of the panel consists of air almost one hundred percent (more precisely, 98 percent), which implies its main properties.

For the installation of fixed elements of the formwork of floors and walls, special foamed polystyrene with a density of 15 to 25 kg / cu. m and thickness for external walls from 1 2 cm, for internal at least 5 centimeters.

Encased in concrete reinforced slabs turn into a reliable monolithic design.

3D panel device

1. Shotcrete 55-60 millimeters, usually not lower than B20
2. Reinforcing wire mesh d = 3 mm, cell size 5 x 5 centimeters
3. Expanded polystyrene foam
4. Diagonal made of galvanized or stainless steel wire d=4 mm

How panels are concreted

Panels are concreted using the shotcrete method: a mixture of cement and sand is fed through a hose and sprayed onto the wall surface at high speed under pressure. Due to the bombardment, the applied mixture is compacted.

In one pass, by shotcrete, a layer with a thickness of 12-15 millimeters can be obtained.

What is shotcrete

Shotcrete (from the Latin "tor" - plaster and the Latin "cret" - compaction, compacted) is a type of construction during which the building concrete mixture is applied in layers directly onto the wall. Shotcrete is carried out with special equipment: a hopper sprayer (bunker gun) or a shotcrete installation.

The physical and mechanical properties of shotcrete differ from the properties of a conventional solution; higher density (about 2400 kg / cubic meter), mechanical strength(40-70 MPa), water resistance and frost resistance (at least Mrz 300). The high adhesion of shotcrete allows it to be laid using even one-sided formwork.

2 ways of applying concrete when shotcrete

Depending on the equipment chosen, concrete is applied to the walls in one of two ways. During dry shotcrete, a dry mixture is supplied through the hose, at the base of the nozzle it combines with water and is ejected under pressure onto the surface to be treated. You do not need to pre-mix the mortar, and you can apply a thicker layer of concrete in one pass. The coating turns out to be rough and requires mandatory finishing, but it has high strength and is securely fixed on any base.

Despite the name, the "wet" method of shotcrete, in which a ready-made concrete mixture is fed through a hose, is much cleaner: there will be less dust and dirt on the construction site. The composition of the concrete is more uniform, and the wall covering looks neater than with dry shotcrete. In addition, concrete prepared for shotcrete can then be used for other work and applied by hand, by hand, where it is needed.

Fixed formwork from 3D panels

The technology of building houses using reinforced panels to create fixed formwork allows you to build houses in a short time.

The shotcrete structure is more reliable than conventional reinforced concrete structures. 3D panels are classified as non-flammable and do not require additional protection, and the expanded polystyrene insert is reliably protected from melting from both sides by concrete. The low weight of the panels makes it possible to build warm and cozy houses even on moving soils (sandy and swampy soils), in seismic zones, and also to build floors on finished buildings without strengthening the foundation.

Do-it-yourself installation of panels on the 1st floor of the house will take 3-4 days, depending on the amount of work and the number of those “hands”.

Internal communications

Installation of internal engineering networks in houses from "3D panels" it is much more convenient and therefore takes less time than in any other houses built using other technologies.

Channels to enter all engineering communications are laid immediately after the completion of the installation of the panels between the mesh and the polystyrene boards.

All channels for the input of all engineering communications are laid immediately after the installation of the panels between the grid and the polystyrene foam boards: they are easily burned inside the boards with building hair dryer. Laying holes for communications is carried out after the installation of the panels, but always BEFORE shotcrete.

But the same expanded polystyrene prolongs the life of the house, because it is resistant to decay and temperature extremes. By the way, from light panels you can not only build load-bearing walls, but also a plinth, roof, floors. Interior partitions made of 3D panels have excellent sound insulation; you can hang shelves and mirrors on them without strengthening the structure.

Do-it-yourself house from 3D panels - construction progress (photo)

1. First, the foundation is poured: slab or tape, monolithic. Mark the position of the reinforcing bars (these are outlets from the foundation with a diameter of about ten millimeters) and install them from the inside of the load-bearing walls in increments. Do this, of course, until the concrete has hardened. Reinforcing rods serve to facilitate the installation of wall panels and prevent their displacement.

2. After the end of the first stage, the panels are cut to the right sizes: first cut the mesh from the reinforcement, then cut the foam itself located inside.

3. Installation starts from the corner of the building. The panel is attached to reinforcing bars, which are installed around the entire perimeter of the foundation, using soft wire. To ensure rigidity, the joints of the panels are covered with connecting meshes using a knitting wire and an air gun.

4. The panels are fixed with temporary supports for stability.

5. Cut through window and door openings. The corners are fixed with a mesh at an angle of 45 degrees, and the perimeter is further reinforced with reinforcement on both sides.

6. Upon completion of the installation of the walls of the first floor, a monolithic reinforced concrete floor is erected from the same panels. The base plates are reinforced with clamps with d = 8 mm and with a step of 20-25 cm. The horizontality of the overlap is provided by temporary spacers, they also prevent the structures from moving when shotcrete is sprayed. After the concrete has hardened, the spacers are removed.

7. Before pouring the walls, they once again check the accuracy of the design parameters, lay communications. Shotcrete is then applied to the surface.

8. Exterior and interior wall decoration can be any. It is better to apply a massive finishing coating on the walls immediately after shotcrete, it will be securely fixed on the facade of the house.

Important: Reinforced panel structures need a grounded loop!

Note: Grounding is not required if you are using composite reinforcing materials.

NATURAL MATERIALS FOR WARMING AND DECOR

If we love natural materials of natural origin, we will use them to insulate the house. These include: straw concrete, sawdust concrete, adobe, hemp concrete, as well as lightweight concrete - foam concrete, aerated concrete, gas silicate blocks, foam fiber concrete, stone wool etc. We will give strength to the house with an armored concrete structure, the thickness of which can be small with high strength, resistance to reagents and durability as a concrete mixture. This reduces the cost of concrete mortar, but increases the strength and durability of the aesthetic qualities of the house. Also, reinforced concrete structures, with their low cost and ease of execution, allow you to create any kind of garden sculpture on the site, model an unlimited number of types of finishes and create a wide variety of small architectural forms for an atmosphere of comfort, convenience and beauty around the house

PRINCIPAL DIAGRAM OF KNITTING REINFORCEMENTS AND MESH

Among wall materials made of lightweight concrete, gas blocks are at the peak of popularity. Today, a private developer chooses not so much the type of blocks as the manufacturer. You can buy a quality block more expensive, but you can save money. Both options are viable. How not to overpay when building a house from wall blocks? Advice is given by professional builders and architects.

On the Russian market building materials today there are about two dozen varieties of wall blocks made of lightweight (cellular) concrete. From the "veteran" cinder concrete to the still little-known vermiculite concrete. A survey conducted among Yekaterinburg architects and builders showed that in the segment of materials for the construction of private residential buildings today gas blocks are in the lead (they also include gas silicate, gas-ash blocks), foam blocks are the second most popular, followed by lightweight concrete with wood chips filler (arbolit, brisolite) and some other products. The once popular expanded clay and cinder blocks are now used mainly for outbuildings.

In addition to the type of material that wall "products" consist of, important role plays the technology of their manufacture.

Alexey Rusakovich

Private developers usually use aerated concrete blocks autoclaved with a density of 500-600 kg. per cubic metre. This is very a good choice. The “monsters” of the gas block are such enterprises as Porevit, Aeroc, INSI-block, Knauf.

In addition, Yekaterinburg builders speak positively about the products of the Betolex, Betfor, and Teplit factories. These enterprises make wall blocks using autoclave technology. Aerated concrete hardens in autoclaves at high temperature, humidity and pressure. As a result, the strength of the blocks is much higher than if hardening took place under atmospheric conditions. In addition, autoclave blocks practically do not shrink during operation. Whereas the dimensions of a block ripened on the street can change by 2-3 cm. The mentioned factories give certificates for their products, which indicate its characteristics, primarily density, strength and thermal conductivity.

In addition to stable physical characteristics blocks from responsible manufacturers have the shape of an almost perfect parallelepiped. Or a parallelepiped with grooves and ridges, if we are talking about a tongue-and-groove mounting system.

Alexey Zykov

At the same time, there are a large number of gas and foam blocks on the market made by incomprehensible manufacturers in a garage or in similar conditions. It is clear that the characteristics of such products are a great secret. It is not always possible to distinguish a quality block from substandard by eye. You can check the product in a special laboratory, but some research can really be done on your own. Pay attention to the state in which the blocks arrived. If they are of high quality, then the corners will be intact and there will be no cracks. For the second test, you will need an axe. Autoclaved aerated concrete is very difficult to cut. Well, the simplest test is to screw a wood screw into the block. From a quality product, it will not work to pull it out by hand.

Block "from the garage" is also good

The chief engineer of the ASR company, Alexei Rusakovich, notices that for the construction of one two-story house usually the bearing capacity of gas blocks made "in the garage" is enough. True, before deciding to use such material, it should be tested, and preferably not only on your own. In Yekaterinburg, there are several organizations that have the opportunity to determine the strength characteristics of wall blocks (LLC Stroy-Expertiza, LLC PIK Construction Quality Center, etc.). The cost of such a service starts from 2–2.5 thousand rubles. If you also need to determine the moisture content of the blocks, then the price tag will increase by about 2.5 thousand rubles.

Alexey Rusakovich

We had cases when the customer asked to design a house from some strange blocks, which he got by chance or on account of a debt. We sent blocks for research. And on the basis of the test report, the project was corrected. If there are concerns about strength, it is possible to strengthen the house with load-bearing columns, provide for a monolithic unloading belt, or other measures. By the way, the monolithic strapping under interfloor overlap and under the rafters is also necessary if the house is being built from the highest quality gas blocks.

Builders admit that most of the gas and foam blocks made in the garage, despite their low quality, are suitable for building a cottage with not very high ceilings and a second attic or semi-attic floor. Even without load-bearing columns and other additions. The cost of "garage" gas blocks is almost half as much as autoclave ones from a trusted manufacturer. The first cost from 2 thousand rubles. per cubic meter, the second - from 3.5 thousand cubic meters.

If the customer is forced to save money, then he is tempted to build a house from the cheapest blocks. It is believed that after plastering inside and applying a facade finish on the outside, block defects will not be visible. Experts believe that such a point of view has a right to exist.

Evgeny Davydov

From blocks Low quality it is possible to erect walls of a house with acceptable strength and thermal characteristics, however, in this case, the question of qualification of masons becomes fundamental. It is more difficult to lay out even walls from such blocks than from factory ones, plus the time for production of work increases, and due to the increase in the thickness of the seams (to level the dimensions of the block), the thermal characteristics of the wall decrease. In addition, it is necessary to correctly carry out the bearing armored belt, to which all loads from overlying structures (walls, roofs, interior decoration and furniture), snow and wind. Blocks "from the garage" have poor geometry and low strength characteristics. Volume weight, compressive strength and thermal characteristics of such blocks may vary depending on the batch and the conditions for their strength gain.

As Aleksey Zykov, director of Magistral LLC, notes, the box of the house, lined with high-quality autoclaved blocks, has good rigidity. It will retain its geometry even if the foundation is weak. A house built from "garage" blocks will not have such a margin of safety.

High-quality block - saving on masonry

As for the money side of the issue, as the builders notice, trying to save money on buying blocks will result in overspending on other materials. First of all - on the glue for masonry. When laying blocks with poor geometry, the consumption of glue increases by 2-3 times. That is, due to the "extra" glue, the cost of 1 cubic meter of masonry will increase by 100-150 rubles.

Alexey Zykov

Instead of a special adhesive for cellular concrete, some take a cheaper cement mortar. It is not a pity to put it in a thick layer when laying curved blocks. However, this is a bad decision. Gas-foam blocks have a different coefficient of thermal expansion than cement mortar. The durability of such masonry will be lower than when using glue, the characteristics of which are specially selected for blocks of lightweight concrete.

Evgeny Davydov draws attention to another aspect of using a solution instead of glue. If the masonry, as expected, is made on glue, then it is easy to lay channels for engineering networks on the inside of the walls - just run a special tool along the markings. If the masonry is made on a cement mortar, then when chasing, you will have to use a perforator to punch through concrete joints.

... And on the interior decoration

The curved geometry of blocks from "garage" manufacturers leads to overspending not only of masonry adhesive, but also to additional costs for interior decoration.

Evgeny Davydov

A wall laid out of uneven blocks must be plastered from the inside along the beacons with a layer of at least 15 mm. The cost of this work with materials from 450 rubles. If the wall is made of high quality blocks with ideal geometry, then you can do without plastering the internal walls. Enough putty. However, this is rarely done. Usually visual plastering is used. Cost including materials - from 260 rubles. per sq. m.

Insulation and facade

The low strength of the "garage spill" blocks can become a problem when installing insulation and facade decoration.

Oksana Kosinova

Blocks made of cellular concrete have low thermal conductivity. In the Urals, with an aerated concrete wall thickness of 40 cm, it is theoretically possible to do without additional insulation. However, to insure against possible masonry defects, I usually use a layer of basalt or mineral wool. 5 cm is enough. If the wall thickness is 30 cm, then the mineral wool layer will be 10–15 cm. The insulation boards are attached to the wall with “mushrooms”. If the wall blocks are of very poor quality, then the "mushrooms" will not hold. The facade will start to fall off.

More big problems are possible if the customer intends to use a hinged ventilated facade. Hanging elements (siding, porcelain tiles, etc.) are attached to the wall with anchors. Even a wall made of high-quality lightweight concrete is capable of carrying only light versions of a hinged facade (plastic or metal siding). With gas blocks "from the garage" it will not work to organize a hinged facade. Or, as Aleksey Rusakovich advises, it is possible to provide for embedded parts in the wall for mounting hinged panels even at the design stage.

Alexander Bonetsky

In my opinion, a good option for exterior wall decoration from a gas block is lining with facade bricks. The load from such an outer layer will not fall on the wall, but on the foundation. True, you will have to increase the dimensions of the foundation in order to fit the outer layer of bricks. Consequently, the cost of the zero stage of construction will increase. On the other hand, the outer layer of brick will not allow intruders to open the wall with a crowbar or sledgehammer. For some customers, this is an important point.

According to Evgeny Davydov, Director of Vertical Group, in terms of price / quality ratio, one of the best finishing options for a house made of lightweight concrete is wet plaster. The expert advises using the materials of the Ceresit (Ceresit) line: primer, glue, mesh, rough and finishing plaster, as well as paint. Plaster on the grid is applied over the thermal insulation boards, which, in turn, are attached to the wall of gas blocks using not only “mushrooms”, but also glue. As Aleksey Zykov, director of Magistral LLC, notes, if a plaster facade is used, the installation of thermal insulation must be carried out using glue in order to defeat the thermal expansion of materials.

Alexey Zykov

With a thickness of a gas-foam block of 30 cm, 5 cm of insulation is enough. But then, during its installation, it is necessary to adjust the plates so that the joints between them do not coincide with the joints between the blocks. Therefore, the following scheme is often used: 5-centimeter plates are mounted on top of the wall in two layers with an overlap. This fully guarantees against through cracks.

The cost of installing thermal insulation on the wall, taking into account the price of "mushrooms" and glue - 180-350 rubles. per sq. m., the cost of a 5-centimeter insulation is 80–120 rubles. per square. The price tag for exterior plaster, taking into account the application work, is usually in the range of 600–800 rubles. per sq. m. Decorative plaster ("bark beetle" and similar textures) will cost 2-3 thousand rubles. per square. Exclusive Options coatings can cost many times more.

Can be done without insulation

As already mentioned, according to calculations, a wall made of lightweight concrete (with a density of 500–600 kg per cubic meter) 40 cm thick in the conditions of the Urals has sufficient thermal insulation properties. Theoretically, a house built from 40-centimeter blocks can be simply plastered. In practice, this is rarely done. As Aleksey Zykov explained, even if the masonry is done by a qualified master, he cannot always ensure the complete absence of vertical slots. The side surface of the block is large enough. When it joins with an already lying block, the air does not have time to leave the gap and a bubble forms in the thickness of the glue on the vertical seam. It is impossible to see him.

To a certain extent, blocks with a tongue-and-groove system can solve the problem of vertical seams. When they are installed, the vertical seam is not through, but broken. A large bubble cannot form, and a few small isolated voids cannot become cold bridges.

Oksana Kosinova

A gas block house will have good thermal characteristics, but only under conditions of good quality masonry. Also, do not forget about the strapping reinforced belt, on which the floor slabs rest. This belt is made of monolithic concrete and is a cold bridge. If it is decided to build a house without external insulation, then the belt is made a little narrower than the width of the wall - not 40 cm, but 30. The remaining 10 cm thickness is covered with polystyrene foam. So we eliminate the bridge of cold.

Tab. 1 Cost of 1 sq. m. walls of gas blocks of different quality (rub.)

* The cost of blocks is indicated close to the lower limit of the market. Autoclaves - from 3500 rubles, "garage" - from 2000 rubles. per cubic meter.

** When calculating the cost of masonry, the average prices for masonry blocks in force in Yekaterinburg in March-April 2015 were taken, namely, 1200 rubles. per cubic meter of blocks. In general, the range of prices for such work in the specified period is 600-2500 rubles. per cube

Other lightweight concretes

In addition to gas and foam blocks, expanded clay blocks and polystyrene concrete blocks are used in the construction of private houses in the Urals. But their popularity is relatively low.

Alexander Bonetsky

The bearing properties of polystyrene concrete are much lower than those of aerated concrete. It can only be used as a protective material. In addition, polystyrene concrete blocks from some manufacturers are afraid of fire - they simply burn. I checked myself. As for expanded clay blocks, I have not come across their use for a long time. Perhaps they are on the market, but in small quantities.

Somewhat more common today are lightweight concretes, the aggregate in which is crushed wood chips. This is primarily arbolite and brisolite. Arbolite blocks differ little from their counterparts made of gas-foam concrete, although “sawdust bricks” are much less common. Brizolit is a fixed formwork system also made of sawdust concrete. Repair.Divandi will tell you more about this material in one of the upcoming publications on construction using fixed formwork.

From the line of wall products made of lightweight concrete, heat blocks are worth mentioning separately. They are sandwiches, in each of which are assembled together: an element of the outer facade cladding, a layer of thermal insulation (expanded polystyrene) and a supporting "brick" (usually made of expanded clay concrete). Interviewed Renovation.Divandi builders and architects are wary of this material. In their opinion, when laying heat blocks, it is difficult to ensure the tightness of through seams.

Oksana Kosinova

Good quality masonry from heat blocks is possible only with their ideal geometry. After all, no flaws to hide the exterior finish will not work. We had to deal with such products in which the geometry was broken. For example, skewed facade element, because of the fragile tendrils that attach it to the block of thermal insulation. In addition, the laying of heat blocks is a very time-consuming process. In order not to form through cracks, in addition to the masonry mortar, it is necessary to use mounting foam. The bricklayer turns into a juggler with a huge number of objects in his hands.

Private developers are also deterred by the limited choice of facade finishes. Manufacturers offer almost exclusively imitation of masonry made of stone bricks with the texture of torn rock. Only the color of the "stone" differs.

At the same time, many people are attracted to the heat block by the fact that a house can be built from it faster than using other lightweight concrete products. And the price of such a building will be quite democratic.

Lightweight concretes include all types of concrete whose density is below 1800 kg/m³. But this is the maximum figure, while the average density of lightweight concrete ranges from 500-800 kg / m³. Key Feature material - high porosity - up to 40% of the total volume. It is a natural result of the high content of aggregate in the composition - fine gravel, tuff, pumice, expanded clay, perlite, vermiculite, etc.
Types of lightweight concrete is a complex issue because there are at least 5 possible classifications. The most useful one can be called the one that offers to do them as intended for:

1. heat-insulating- retain heat well as a result of high porosity: the density of this type is only 500 kg / m³, there are many voids inside that create " air cushion»;
2. structural and heat-insulating- characterized by an optimal combination of density (1400 kg / m³), ​​strength (class M35) and thermal conductivity (0.6 W);
3. structural– with maximum density for its class (1800 kg/m³), strength (M50) and high frost resistance (F15).

Light and heavy concrete are equally often used in monolithic construction, but for different tasks depending on destination. Some varieties are in demand for arranging premises with a certain temperature regime. Others are suitable for building walls and ceilings. Still others - exclusively for load-bearing structures.

TBAS widely uses lightweight concrete on porous aggregates in the process of building houses from monolithic concrete. In the production process, we strictly follow the requirements of GOST, we use fillers different types, obtaining a material with a high level of frost resistance, strength and low weight. From which durable and reliable houses are obtained!

The walls of low-rise residential buildings do not experience heavy loads and building materials with relatively low strength can be successfully used for their construction. These materials include lightweight concretes prepared on the basis of local aggregates (slag, broken bricks, sawdust, reeds, straw) using cement, lime, clay and gypsum as binders.

Slag concrete. By mixing fuel or metallurgical slag with a binder, one can obtain a relatively light and durable material- cinder block. In terms of its heat-shielding qualities, it is 1.5 times more effective than solid brick, and at a cost about the same times cheaper than it. Cinder-block walls are relatively durable: correct masonry, good moisture protection and reliable foundations, their service life is at least 50 years. Usually, fuel slags are used to produce slag concrete. They are more affordable than metallurgical ones, although they are inferior to them in terms of strength. Of the fuel slags, the most durable and persistent are slags obtained from the combustion of anthracites. The slags of brown and Moscow region coals contain many unstable impurities and are of little use for this purpose. All other coals give slags with intermediate properties that allow them to be widely used to produce cinder concrete.
The slag must be clean and free from foreign impurities: earth, clay, ash, unburned coal and debris. To reduce the content of unbaked clay particles and harmful salts, fresh slag is kept for a year in dumps in the open air, ensuring free drainage of rain and flood waters during its storage.

The strength and heat-shielding qualities of slag concrete largely depend on its granulometric composition, that is, on the ratio of large (5-40 mm) and small (0.2-5 mm) parts of the slag filler. With coarse slag, concrete is lighter and less durable, with fine slag, it is more dense and heat-conducting. For external walls, the optimal ratio of fine and coarse slag is from 3:7 to 4:6, for internal load-bearing walls, where the main advantage is strength, this ratio changes in favor of fine slag, and lumpy slag larger than 10 mm in the composition of cinder concrete in this case is not included at all. For strength, part of the finest slag (about 20% of the total volume) is replaced with sand. For cinder block as binder cement with lime or clay additives is used. Additives reduce cement consumption and make cinder concrete more plastic and workable. The approximate composition of slag concrete is shown in Table. nineteen .

Table 19 Composition of slag concrete

Slag concrete is prepared in the same sequence as regular concrete. First, cement, sand and slag are mixed in dry form (large pieces are pre-moistened), then lime and clay dough, water are added and again everything is thoroughly mixed. The finished mixture is used in business for 1.5-2 hours. Monolithic cinder-block walls are erected in adjustable formwork 40-60 cm high, knocked down from thick boards (Fig. 39, "Moving formwork", 1 - cinder block; 2 - formwork shield; 3 - glassine; 4 - racks; 5 - spacer; 6 - wire twist; 7 - wedges ) .

Formwork shields are usually attached to fixed posts with a diameter of 10-15 cm, installed on both sides of the future wall through 1-1.5 m along the front to the full height. Temporary spacers are inserted inside the shields, and wedges are inserted between the posts and shields. The areas of application of various types of formwork are given in table. 20 .

Table 20 Scope of various types of formwork

Slag concrete is laid in layers of 15-20 cm with uniform compaction and bayonet. After two or three days, and in warm weather, after a day, the formwork is rearranged. The laid slag concrete is shaded from direct sunlight for seven to ten days, and in dry weather it is periodically moistened. Monolithic walls can be built with internal voids. This improves the heat-shielding qualities of the walls and reduces the consumption of slag concrete. As void formers, inserts made of lighter concrete, foam plastic, old newspapers and cardboard, milk bags, etc. can be used. However, it should be borne in mind that voids weaken the bearing capacity of walls, so the strength of cinder concrete in this case must be increased. Trim (plaster) monolithic walls it is possible not earlier than three to four weeks after their erection, when the cinder concrete is completely dry and gains the necessary strength.

A good technological solution is obtained when constructing monolithic cinder-concrete walls with an external brick cladding (Fig. 40, "Cinder block wall with brick cladding") which gives the wall a more solid appearance, does not require subsequent finishing (with brickwork with jointing), and in the process of concreting it acts as an external formwork.

To speed up construction works, cinder-block walls are made from prefabricated blocks. This not only saves time, but also allows you to immediately get dry walls, ready for finishing work. If there are no ready-made prefabricated blocks, they can be made in advance on their own in construction conditions. For the formation of blocks, wooden collapsible forms are usually used, made in the form of boxes without a bottom with two connectors located diagonally (Fig. 41, "Collapsible mold for the manufacture of reinforced concrete blocks" ) .

So that the inner walls of the molds do not absorb water and are better cleaned, they are upholstered with metal, plastic or painted with nitro enamel. The dimensions of the blocks depend on the thickness of the walls, the width of the openings and walls, the ease of carrying and laying (one of possible sizes:
390x190x190 mm). With a rigid cinder-concrete mixture and good compaction, it is possible to sequentially strip the blocks immediately after their manufacture. The molded blocks are left in the shade under a canopy for two to three weeks. In dry and windy weather, they are periodically moistened in the first five to seven days. For the formation of voids, the same void formers are used as in monolithic walls.

sawdust concrete. In areas where there is waste from the timber industry, sawdust can serve as a good aggregate for lightweight concrete. In a mixture with a binder, it is possible to obtain a warm and fire-resistant material under construction conditions - sawdust concrete. In terms of heat-shielding qualities, it, like slag concrete, is much more effective than solid brick, and in terms of sanitary and hygienic indicators, of all concrete materials considered to be the most comfortable for residential buildings. At the same time, having an organic filler in its composition, sawdust concrete needs reliable moisture protection both from the outside and from the inside. On the outside, the walls are usually plastered cement-sand mortar or lined with bricks, from the inside - plastered or sheathed with boards, plywood, wood-fiber boards with a parchment or synthetic film vapor barrier. Sawdust is used as a filler conifers wood, as they are less susceptible to biological degradation. The best binder is cement. To save money, some of it is replaced with lime or clay. There are many recipes for obtaining sawdust concrete. All of them depend mainly on the quality of the binders and the composition of the aggregates. The main requirement is that the amount of binders should not be less than the dry mass of aggregates, that is, if 50 kg of sawdust is used, then the binders in total should be at least 50 kg. To increase strength and reduce shrinkage, sand is added to sawdust concrete. The approximate composition of sawdust concrete is given in table. 21 .

Table 21 Composition of sawdust concrete

Sawdust concrete is prepared in the same way as slag concrete: first dry sand, sawdust and cement are mixed until a homogeneous mass is obtained, then in small portions, preferably through a mesh watering can, water is added and everything is mixed again. Ready mix when squeezed in a fist, it should form a lump without the appearance of water. Sawdust-concrete walls are usually laid out from ready-made sawdust blocks. Sawdust concrete hardens very slowly, retaining an easily deformable state for a long time (it springs when tamping) and therefore is inconvenient to lay. Masonry walls from pre-prepared blocks are more rational. In this case, it is possible to work out the technology for producing sawdust concrete more carefully, to produce in advance strong and dry wall blocks that are not subject to subsequent shrinkage, and to significantly reduce the time directly spent on building walls. Wall blocks from sawdust concrete, as well as cinder blocks, are made in collapsible forms. But due to the fact that the stripping strength of sawdust concrete, which allows removing the mold from the product, does not occur immediately after formation, several collapsible molds are required to be used simultaneously. The dimensions of the blocks are also chosen taking into account the thickness of the walls, the laying methods and the ease of carrying. Thick blocks (more than 20 cm) do not dry well, and heavy ones (more than 20 kg) are inconvenient to carry and stack.

The thickness of the outer walls depends on the bulk density of the sawdust concrete and the design temperature of the outside air. With a bulk density of 800 kg / m 3, the thickness of the walls is taken: 25 cm - at an estimated winter air temperature of -20ºС, 35 cm - at -30ºС, 45 cm - at -40ºС. Internal load-bearing walls are laid out with a thickness of at least 30 cm. necessary cases(bearing walls and pillars) horizontal seams reinforce metal mesh from wire with a diameter of 3-5 mm with cells of 6-12 cm. Lintels over door and window openings in walls made of lightweight concrete, as a rule, ordinary ones are arranged, that is, along the course of masonry from a monolithic reinforced concrete belt 30-40 mm thick, laid on a wooden formwork, or from wooden bars 1/20 of the span high. The length of the supporting parts of the jumpers is 40-50 cm on each side of the opening. The durability of walls made of lightweight concrete blocks increases significantly if instead of exterior plaster line them with brick (Fig. 42, "Brick lining of lightweight concrete walls", a - a wall of cinder blocks; b - a wall of sawdust concrete blocks; 1 - brick lining; 2 - mineral felt; 3- cinder blocks; 4 - gypsum concrete slabs; 5 - metal bonds; 6 - sawdust concrete blocks; 7 - air gap; 8 - plaster ) .

A brick wall can adjoin directly to cinder concrete, and it should be 3-5 cm away from sawdust concrete. The ligation of the cladding with the wall is performed with metal ties made of wire with a diameter of 4-6 mm at a distance of 1-1.5 m along the front of the wall, after four to six ranks brickwork. To protect against corrosion, wire ties are coated with bitumen, cement mortar or epoxy resin. In the process of building a house, it may be necessary to erect rubble walls (most often these are outbuildings).
These walls are durable, not combustible, but they are distinguished by high thermal conductivity. They should be 50 cm thick. Brick and cinder blocks are used for laying walls. Cinder blocks are laid in even rows, carefully dressing the seams. The solution can be taken clay, lime, cement-lime, cement-clay. When plastering the walls, the laying is carried out "into the wasteland", that is, without filling the joints with mortar to a depth of at least 10 mm; wire is inserted into the seams, and so that its ends protrude from the wall. Wire braiding holds the plaster firmly.

The walls can also be thinner (up to 40 cm), if for their cladding from the outer and inner sides, slabs of fiberboard and cinder concrete with a thickness of at least 7 cm are used. To fasten the slabs, wooden plugs or slats are inserted into the seams during masonry. On the inside of the plate, they are placed at a distance of 4-5 cm from the wall, creating an air gap. Lintels over window or doorways must be from antiseptic bars with a thickness of at least 10 cm. Their ends are insulated with roofing felt or roofing material, and also covered with bitumen. Instead of wooden lintels, prefabricated reinforced concrete can be used. It is easy to make them yourself: 8-10 bars of reinforcement with a thickness of at least 6 mm are placed in the formwork along the length of the jumper and fastened with wire with transverse bars, the number of which should be at least 10. The reinforcement is raised above the formwork by 3-4 cm and poured with a layer of concrete not less than 7 cm thick. The ends of jumpers made of any material are laid in walls (piers) to a depth of at least 25 cm.

Rubble masonry lead with obligatory dressing of seams. Larger stones should be laid at the corners and outer edges; the stones of the first row must be tamped into the ground, following the same order as with cobblestone. In order for the rows to be horizontal and of the same height, the stones should be selected with the same thickness (usually no more than 300 mm). Having laid the stones along the edges of the trench and forming the so-called "verst", resembling the sides, they put a solution into it, level it, lay large stones as close as possible to each other, and fill the gaps between them with gravel and compact it all. From above, the "verst" is poured with a more liquid solution. The second row is laid on the first row, observing the dressing of the seams, etc. Both cobblestone and rubble masonry can be carried out in the formwork, which is removed after 2-3 days or after completion of work.

Rubble concrete masonry lead at odds with the walls of the trenches, but more often - in the formwork. The first row can be laid as in rubble masonry, but it can also be done this way: first, the soil is well tamped, the concrete mass is poured with a layer of 150-200 mm and rubble stone is sunk into it in horizontal rows with a height of no more than 300 mm and a width of 11 no more than 1/3 of the width foundation. The stones must be sunk in so that they are at least 50 mm from the formwork, and the distance between them is no more than 40-60 mm. The preparation of the concrete mass and the insertion of stones into it should last no more than 1.5 hours. The top of each row is cleaned of debris and dust, moistened with water and the next row is laid.
Currently, single-layer wall panels made of lightweight or cellular concrete are used in construction: expanded clay concrete, perlite concrete, slag concrete, ash-perlite concrete. The concept of "single-layer panel" is conditional. In fact, the so-called "single-layer panel" consists of a main structural layer of lightweight or cellular concrete, located between the inner finishing and outer protective-finishing layers. The inner finishing layer is made of a heavy mortar with a density of 1800 kg/m 3 and a thickness of 15 mm to protect the main layer of the panel from dampness due to the penetration of internal air vapor into it.

The outer or facade protective and finishing layer of lightweight concrete panels is made 10-25 mm thick from vapor-permeable materials - concrete, mortar, ceramic and glass tiles providing the necessary waterproofing. The protective and finishing layer of the cellular concrete panel is made from solutions with a density of 1200-1400 kg / m 3, tiles, coated with paints. Increasing the heat-shielding characteristics of single-layer panels is carried out by reducing the density of lightweight concrete from 1400 kg/m 3 to 700-900 kg/m 3 , using cellular concrete and other highly efficient heat-insulating materials. The most widely used in the construction of residential buildings are single-layer panels, somewhat less - three-layer.

Three-layer concrete panels have two structural layers of heavy or lightweight concrete (internal and external) and an insulating layer enclosed between them. As an insulating layer, materials with a density of less than 400 kg / m 3 are used in the form of blocks, slabs or mats of mineral or glass wool on a synthetic binder, polystyrene foam, fiberboard, foam glass. They begin to use filler foam for insulation of panels, which polymerize in the internal cavity of the panel.

The thickness of the inner and outer structural layers should be taken from the ratio of 1.2:1, preventing the accumulation of moisture in the thickness of the insulation. To do this, you can also use a vapor barrier made of foil, roofing material, etc., placing them between the insulation layer and the inner structural layer. Concrete layers of the panel are connected by flexible or rigid connections, which ensure the unity of all layers of the panel and meet the requirements of strength, durability and thermal protection. Rigid connections between the layers are transverse reinforced ribs molded from heavy or light concrete. Their advantage lies in the rigid connection of the layers, the protection of reinforcement from corrosion, the ability to use heaters. various types. At the same time, rigid ribs are heat-conducting inclusions; reducing the thermal protection of the panel, can lead to condensation on the very ribs and in the zone of their influence on the inner surface of the wall. To avoid this, the thickness of the ribs is prescribed no more than 40 mm, the inner finishing layer - 80-120 mm. Due to this, the temperature distribution on the inner surface of the panel becomes more uniform and the probability of temperature drop on the inner surface of the panel below the dew point is reduced.