Gas silicate building blocks are a building material universal significance. It is an artificial porous stone. This structure is formed by a natural chemical reaction between aluminum and lime. During the reaction, these two components break down and form hydrogen.

Gas silicate blocks undergo heat treatment (up to +190°C) under a pressure of 10-12 bar. Thanks to this material, additional strength is imparted, and thermal conductivity and frost resistance are improved.

was developed in Sweden at the beginning of the last century, but gained popularity only recently. It has undergone virtually no changes over time, which speaks of its convenience, simplicity and reliability.

Types of gas silicate blocks

All gas silicate blocks can be divided into three types:

Aerated concrete represents fake diamond. Its array contains closed air cells no more than 3 mm in diameter. The main components are: sand, cement, a set of gas-forming components. Air pores significantly increase its thermal conductivity.

Foam concrete- This is a material similar to aerated concrete. The differences are in the production method. Cells are formed due to the introduction of foaming additives. The main components are: quartz, lime and cement.

Gas silicate– a building material formed by autoclave hardening. Its components are: crushed sand and lime, aluminum powder. Lighter in weight and best performance thermal conductivity.

Video about what you need to know about gas silicate blocks as a building material:

Classification by area of ​​application

Wall blocks Designed for laying walls with minimal seams. In the manufacturing process of this material, new technologies are used, which include the use of cement, quartz sand, water and lime. Aluminum powder is used to form pores.

Depending on the density of the material, they can be used both for insulation (density 350 kg/m3) and for low-rise construction (400-500 kg/m3). Wall blocks are larger in size, which reduces material and labor costs.

Today it is a very common occurrence. Such a high popularity of gas silicate blocks is due to their low cost and thermal conductivity, which allows for energy-efficient buildings.

Partition blocks can be used for the construction of partitions and walls. For interior walls apartments, blocks 10 centimeters thick are suitable. The height and width of 100 mm blocks are not significant.

Average sizes of partition blocks for interior walls 200*200*400mm, there are also very thin blocks with a thickness of 50 mm.

They are easy to install and have a number of advantages:

• Good sound and thermal insulation properties;
• Economical;
• Light weight;
• Low cost.

In addition to the advantages, these blocks also have disadvantages:

• Difficulty in processing;
• Low strength;
• High costs for further operation.

This is only a small part of such a building material as gas silicate. In this article you can get acquainted with a more detailed list.

Types of blocks depending on size and strength categories

• Dry laying using glue. Blocks with 1 accuracy category allow deviations: in size up to 1.5 mm; in straightness of edges and edges – up to 2 mm; broken corners – up to 2 mm; broken ribs – no more than 5 mm. (Standard size of gas silicate block is 600x400x200)
• Laying with glue. Blocks of the 2nd category of accuracy can differ in size by up to 2 mm, have deviations from the straightness and squareness of edges and faces up to 3 mm, broken corners - up to 2 mm, and edges - up to 5 mm.
• Mortar laying. Accuracy category 3 can have deviations from the block dimensions of up to 3 mm, rectangularity and straightness - up to 4 mm, broken edges - up to 10 mm, and corners - up to 2 mm.

Tongue-and-groove silicate blocks, unlike smooth surfaces, have hand grips. Their scope of application: monolithic frame construction, as well as the construction multi-storey buildings.

When laying, they have a thermal locking function and a guiding function. This system construction can save on adhesive solution.

The picture shows tongue-and-groove gas silicate blocks

Composition of gas silicates

The main component in the production of gas silicate blocks is lime. And therefore, increased demands are placed on it: activity and purity of the composition. The final result directly depends on the quality of this component.

In addition to lime, gas silicate blocks include a mixture of quartz sand, water, cement and aluminum powder. The last component reacts with calcium oxide hydrate, carrying out the process of gas formation. Gas bubbles begin to form even in the initial stages of production, right up to the placement of blocks in autoclaves.

In many ways, the composition and production technology determines the future and operational properties of gas silicate blocks.

Gas silicate grades

Structural grades reflect the purpose of gas silicate blocks:

• D1000-D1200 – intended for the construction of residential, industrial and public buildings and structures;
• D200- D500 – for insulation building structures;
• D500-D900 – structural and thermal insulation products;
• D700 – wall products using the autoclave method.

Depending on the density of the material, gas silicate blocks can be used for the construction of low-rise buildings and multi-storey buildings (up to 9 floors) and differ in the following grades:

• 200-350 – thermal insulation materials;
• 400-600 – for carriers and non-carriers load-bearing walls in low-rise construction;
• 500-700 – for buildings and structures with a height of no more than 3 floors;
• 700 and above – for multi-storey construction using reinforcement.

Regardless of the brand of blocks, before you start building walls made of gas silicate, you need to know the features and.

Gas silicate or foam block

Both of these building materials have the same origin: concrete solution and porous structure. There are differences in the technology for the appearance of bubbles. During the production of foam concrete, bubbles are formed by the interaction of aluminum dust and lime, which release hydrogen.

And the porous structure of gas silicates is achieved by adding a special foaming agent. Both materials harden faster than the air leaves their structure. If in the first option the bubbles try to leave the mixture and rise up, then in the other case they are held by the foaming agent.

When its action stops, the bubbles burst and compact the structure. Therefore, both materials differ in hygroscopicity. It is easier for moisture to get into foam concrete than into gas silicate.

Foam block, unlike gas silicate, has a perfectly smooth surface. It is more difficult for moisture to penetrate into it. If we compare blocks with the same strength, then gas silicate will have less weight. This is explained by its greater porosity.

Table 1

Gas block and gas silicate

A gas block is an artificial stone having cells with a diameter of 1 to 3 mm. They are evenly distributed throughout the entire structure of the material. It is the degree of uniformity of these bubbles that affects the quality of the final material. When producing aerated concrete blocks, the basis is cement with autoclave or natural hardening.

Gas silicate is a material based on lime. In addition to it, the composition includes: sand, water and gas-forming additives. The blocks are autoclaved. The mixture for gas silicate is poured into a mold and undergoes furnace heat treatment, after which the finished block is cut with a string into smaller blocks of the required size.

Aerated blocks have a lower noise insulation coefficient. If gas silicate absorbs moisture and its structure suffers as a result, then the gas block passes it through itself, creating a comfortable microclimate in the room.

Due to their uniform porosity, gas silicate blocks are more durable. And they are more expensive than less durable gas blocks.

table 2

Gas silicate blocks or expanded clay blocks

Important advantages of gas silicate blocks are safety: environmental and technical. The low coefficient of thermal conductivity allows you to withstand contact with natural phenomena and fire, and at the same time retain heat even in severe frosts.

The absence of radioactive substances, heavy metals and other components hazardous to life and health in gas silicate blocks allows the construction of any buildings without fear for one’s health. The strength of the blocks makes it possible to erect 2-3 storey buildings.

But, despite its advantages, gas silicate has a competitor - expanded clay concrete. Its tongue-and-groove structure makes it possible to lay out walls without seams. Such construction eliminates the occurrence of cold bridges and saves adhesive solution.

The porous structure of expanded clay blocks retains heat in the room better than gas silicate blocks. And in terms of frost resistance, it is 15 cycles more than that of competitive material. The cost of these materials is almost equal.

Gas silicate and expanded clay blocks have almost equal physical and chemical properties. They are unrivaled compared to wood and brick - this is also shown by statistics on developers. Gas silicate blocks are more in demand on the market building materials due to its availability and low cost.

Cellular concrete is a type of lightweight concrete of artificial origin. The material is used for the construction of cottages, bathhouses, garages and insulation. Builders have particular confidence in aerated concrete blocks, the technical characteristics of which will be discussed below.

In factory conditions, the material is produced according to the technological documentation adopted at the enterprise, in accordance with GOST. Finished blocks can be produced with locking elements, special pockets for gripping, technological non-through and through voids.

Aerated concrete block size

The standard size is set in accordance with the functional purpose of the product:

• smooth block – length – 600.00 mm, height – 200.00 mm, width – 200.0/250.0/280.0/300.0/360.0/400.0/500.0 mm;
• block for partitions – length – 600.00 mm, height – 200.00 mm, width – 75.00/100.00/120.00/150.00 mm;
• jumper block – length – 500.00 mm, height – 200.00 mm, width – 250.0/300.0/360.0/400.0 mm.

The maximum permissible width of any products is 625.00 mm, width – 500.00 mm, height – 500.00 mm. If the blocks belong to the first category, deviations in geometric dimensions do not exceed 1-3 mm, for the second - 3-4 mm. Products can be produced at the request of the consumer non-standard sizes, but subject to maximum deviations.

Thermal insulation blocks have a density grade of D300-D500, structural and thermal insulation blocks - D500-D900, structural blocks - D1000-D1200. In order to build a house with good thermal insulation and bearing capacity, it’s better to take the D500

Labeling example

Block I/600х300х300/D500/В2.5/F20 GOST 31360 2007

Explanation: block of the first category, height 200.0 mm, length 600.0 mm, width 300.0 mm. Medium density grade D500, class B2.50, frost resistance – F20.

Average density

If we consider factory-made aerated concrete, the density, based on standard indicators, can vary from 200 to 1200 kg/m³. In product labeling, this parameter is marked with the letter D, that is, the material is standardized by brand. In private construction it is advisable to use D400-D600.

The load-bearing capacity of the material is enough to build an object up to three floors However, the installation of a special reinforced concrete armored belt will be required and this, in principle, is not recommended. The master will be forced to use denser aerated concrete with lower thermal insulation. The result is an increase in construction costs.

The dependence of physical and technical parameters on density is considered in tabular data:

Characteristic	Density, average value, kg/m³
	350	400	500
Strength, MPa	1.00-1.50	1.50-2.00	2.50-3.00
Thermal conductivity (coefficient), W/m C	0.090	0.110	0.120
Frost resistance, in cycles	15.00	25.00	35.00
Sound insulation, db 150-450 mm	50.00	55.00	58.00
Fire resistance, h at a thickness of 175 mm	4.00-5.00	4.00-5.00	5.00-6.00
Environmental properties of aerated concrete blocks	2.00	2.00	2.00
Weight of 1 m² wall, kg	145.00	180.00	240.00
Wall thickness with equivalent heat transfer resistance, m	0.350	0.40	0.450

Flexural strength

Aerated concrete has low bending strength, the material is practically devoid of elasticity. The slightest deformation of the base can lead to cracks in the entire structure. House from cellular concrete requires the construction of a monolithic foundation or good base made of heavy concrete. If construction is planned small house, this is simply impractical, and the construction of another foundation generally deprives all actions of any meaning.

Compressive strength

The strength of non-autoclaved and autoclaved aerated concrete is characterized by classes. According to the current standards for the material, they are set as follows - B0.35, B0.50, B0.75, B1.0, B1.50, B2.0, B2.5, B3.5, B5.0, B7.5, B10.0, B12.5, B15.0, B20. For private construction, the compressive strength class must be at least B1.5.

Stable characteristics of strength and density are determined by the coefficients of variation (SN 277, GOST 27005/R53231). The density indicator should not exceed 5%, and the strength indicator should not exceed 15%.

Frost resistance

Taking into account winter temperatures, grades of material are assigned and controlled for frost resistance.. This indicator allows you to understand how many freezing and thawing cycles the block can withstand after water saturation. For aerated concrete, the frost resistance grade can be F15, F25, F35, F50, F75, F100.

Maximum frost resistance is achieved in dense aerated concrete. This is not thermal insulation, but construction material, requiring insulation costs

• F25 – for products used in external walls (GOST aerated concrete blocks);
• F15 is for others.

The ratio of brands and frost resistance classes is shown in the table:

Type of cellular concrete	Mark, D	Autoclaved cellular concrete
		Class, B	Frost resistance, brand
Thermal insulation	200.0	0.350/0.50	—
	250.0	0.50/0.750
	300.0	0.750/1.00
	350.0	1.00/1.50/2.0/2.50
Structural and thermal insulation	400.0	1.0/1.50/2.0	25.0
	500.0	1.50/2.0/2.50	25.0/35.0
	600.0	2.0/2.50/3.50	25.0, 35.0, 50.0, 75.0
Structural	700.0	2.50/3.50/5.00	25.0, 35.0, 50.0, 75.0, 100.0
	800.0	3.50/5.00/7.50
	900.0	3.50/5.00/7.50/10
	1000.0	7.50/10.0/12.50
	1100.0	10.0/12.50/15.0
	1200.0	15.0/17.50/20.0

Vapor permeability and thermal conductivity

All parameters are indicated in the table data:

Aerated concrete	Mark, D	Thermal conductivity	Vapor permeability
Thermal insulation	200.0	0.0480	0.300
	250.0	0.060	0.280
	300.0	0.0720	0.260
	350.0	0.0840	0.250
Structural-insulating	400.0	0.0960	0.230
	450.0	0.1080	0.210
	500.0	0.1200	0.200
	600.0	0.1400	0.160
	700.0	0.1700	0.150
	800.0	0.1900	0.140
Structural	900.0	0.2200	0.120
	1000.0	0.2400	0.110
	1100.0	0.2600	0.100
	1200.0	0.2800	0.090

Based on the thermal conductivity parameters, it can be understood that optimal thickness walls – at least 0.64-1.07 m. Of course, an individual developer can build thinner walls, however, under stable moderate climate conditions, without thirty-degree frosts.

Other characteristics of gas silicate blocks

If the master is building from gas silicate blocks, the technical characteristics discussed below may be useful:

• radiation - specific effective activity of radionuclides should not exceed 370 Bq/kg;
• fire hazard - the material belongs to the non-flammable group;
• shrinkage upon drying should not exceed 0.50 mm/m (aerated concrete blocks GOST 31360 2007).

When building a house, it should be taken into account that blocks made of cellular concrete cannot be used as the main material for the walls of bathrooms and toilets.

Holiday humidity

The parameter under consideration should not exceed the specified values ​​(% by weight):

• 25 – sand-based aerated concrete;
• 30 – made with oil shale ash;
• 35 – block of cellular concrete based on ash.

Marking

Wall blocks made of cellular concrete, produced in accordance with the current standard, must have the following markings:

• Business name;
• trademark;
• Class;
• density/frost resistance grade;
• batch number;
• technical control mark.

Storage and transportation

The material is transported on pallets, secured in shrink film or steel tape. Storage is carried out on pallets or linings. The conditions of keeping the material must exclude its moisture. The blocks are stacked.

What aerated concrete sellers are silent about

Despite such high technical characteristics, the material also has disadvantages, which manufacturers and sellers prefer to remain silent about.

• cellular concrete absorbs moisture, which reduces thermal efficiency and causes deformations that can ruin the finish. Experts advise protecting finished design and the product itself during storage from waterlogging. It is better not to use the material on open facades;
• for implementation facade finishing Frost resistance should be 50 cycles. The most popular D500 blocks are characterized by 25, maximum 35 cycles, which is clearly not enough for such work. The builder will be forced to use more dense material, and accordingly more expensive;
• Fasteners - due to low mechanical strength - must be special, designed for working with cellular concrete. It is expensive;
• manufacturers claim that the thickness of the masonry can be 380 mm, but this is clearly not enough. Subject to all standards, the wall thickness in conditions middle zone the minimum is set as 640 mm, otherwise the owner will expect increased costs for air conditioning and heating. The thickness of the standard block is 50 cm;
• to prevent deformations, it is recommended to build monolithic strip foundations(aerated concrete blocks, Wikipedia);
• When masonry is made from aerated concrete, the internal area of ​​the house suffers, and the lime contained in the masonry initiates corrosion of lintels, fittings, pipelines, and frames.

Aerated concrete is a modern building material with a liberal price, the use of which is justified in certain climatic conditions when constructing low-rise buildings.

One of the properties of aerated concrete blocks - fire resistance - was practically tested in this video:

Gas silicate blocks are a building material of universal importance. It is an artificial porous stone. This structure is formed by a natural chemical reaction between aluminum and lime. During the reaction, these two components break down and form hydrogen.

In conditions of constant rise in energy prices, the need for building materials with high thermal characteristics is increasing. To reduce heat loss in modern projects Aerated concrete and gas silicate blocks are increasingly being used - materials of the class of thermal insulating cellular concrete. They are often confused due to general properties and the same scope. Even specialists cannot always immediately tell a potential customer which material is in front of him - gas silicate or aerated concrete, which is better, what is the difference between them and whether there is any at all. Partly, the confusion is caused by the manufacturers themselves when they define aerated concrete as a type of gas silicate or vice versa.

What is the difference between aerated concrete and gas silicate? In particular, when producing aerated concrete, natural hardening of the block is allowed outdoors, for gas silicate – autoclave ovens are prerequisite. In addition, for aerated concrete blocks the main binding component is cement, while for silicate analogues it is lime. The use of different components affects the color of the finished blocks.

If we talk about specific characteristics, you can notice the following differences:

• Gas silicate blocks have a uniform distribution of hollow cells, which ensures high strength.
• The weight of aerated concrete blocks is much greater, which requires a reinforced foundation during construction.
• In terms of thermal insulation, gas silicate blocks outperform aerated concrete blocks.
• Aerated concrete absorbs moisture better, which provides a greater number of freezing cycles.
• Gas silicate blocks have a more consistent geometry, which makes the finishing of wall structures easier.

Externally, finished products are distinguished by color: gas silicate or autoclaved aerated concrete is almost white, grey colour typical for non-autoclaved aerated concrete.

The average values ​​for each parameter are shown in the following table:

In terms of durability, the materials are identical and can last more than 50 years.

If you answer the question: “What is better, aerated concrete or gas silicate?”, gas silicate blocks have much more technical advantages. However, manufacturing technology forces an increase in the cost of finished products, so aerated concrete blocks are cheaper. Therefore, those who want to build a house from high-quality and modern material choose aerated silicate; those who want to save on construction - give preference to aerated concrete.

In this case, it is necessary to take into account the region of application: in areas with high air humidity, the service life of gas silicate blocks is noticeably reduced.

Composition and production technology of gas silicate blocks

The mixture for the production of gas silicate blocks has the following composition:

• binder (Portland cement according to GOST 10178-76, calcium lime (according to GOST 9179-77);
• silicate or siliceous filler (quartz sand with 85% quartz content, fly ash, etc.);
• lime, with a content of magnesium and calcium oxides of more than 70%, and a slaking speed of up to 15 minutes;
• industrial water;
• gas-forming additive (aluminum powder and others).

Gas silicate belongs to the class of lightweight cellular concrete. This material is a mixture consisting of 3 main components: cement, water and fillers. Lime and quartz sand in a ratio of 0.62:0.24 can act as fillers. We should also talk about the additives that give gas silicate its individual characteristics. Fine aluminum powder acts as an additive. All these components are thoroughly mixed, and under certain conditions, foaming of all these materials occurs. When aluminum powder reacts with lime, hydrogen is released. The huge number of hydrogen bubbles released makes up the porous structure, which is the main hallmark gas silicate. Its structure resembles a concrete “sponge”, since the entire volume of the block consists of cells (bubbles with a diameter of 1-3 mm).

Gas silicate blocks

The cellular structure makes up almost 85% of the volume of the entire block, so this material is very light in weight. First, a mixture of components is prepared in a special mixer for 5 minutes, which includes Portland cement, fine sand (quartz), water, lime and a gasifier (most often, this is an aluminum suspension). Hydrogen produced by the reaction between aluminum paste (powder) and lime forms pores. Bubbles ranging in size from 0.6 to 3 mm are evenly distributed throughout the material.

Basic chemical reactions take place in metal containers or molds. The mixture is subjected to vibration, which promotes swelling and setting. After hardening, all surface irregularities are removed with a steel string. The formation is divided into blocks, and then they are sent to an autoclave unit. The final calibration of the finished blocks is carried out by a milling machine.

Gas silicate blocks are manufactured only using the autoclave method. Aerated concrete blocks can be produced both by autoclave and non-autoclave methods (natural hardening of the mixture):

1. Autoclave processing. This stage significantly improves the technical characteristics of gas silicate. Here for 12 hours at high blood pressure steam treatment is carried out, the temperature of which is almost 200°C. This heating process makes the texture more uniform, thereby improving the strength properties (at least 28 kgf/m²). Its thermal conductivity is 0.09-0.18 W (m∙K), which makes it possible to erect walls in one row (400 cm) in almost any climatic conditions, but excluding the northern regions.
2. Non-autoclave technology. Consists in the natural hardening of the mixture: moistening and drying natural conditions. In this case, it is quite possible to do it yourself, since no special equipment is required. The strength of blocks in such production does not exceed 12 kgf/m².

The first type is more expensive. This is due to significant manufacturing costs, as well as the best technical characteristics of gas silicate blocks produced by this method. They are much stronger, their thermal conductivity coefficient is lower. The pores inside such gas silicate are distributed extremely evenly, which affects the precise compliance of the material with the specified parameters.

Gas silicate blocks: characteristics

Density of gas silicate blocks

The brand and density of gas silicate blocks is indicated in the marking and determines the purpose of the block:

• structural gas silicate blocks – D1000-1200, have a density from 1000 to 1200 kg/m3;
• structural- thermal insulation blocks– D500-900, have a density of 500-900 kg/m3;
• thermal insulation D300-D500, the density of their materials is 300-500 kg/m3.

Blocks of different densities are easy to distinguish from each other visually.

There are several classifications of gas silicate blocks with certain technical characteristics. Today, the following grades of this material are used in construction work. The best option for low-rise construction is gas silicate block d500 and gas silicate block d600.

The digital designation of the brands listed earlier shows the density of the material. In particular, the d500 gas silicate block has a density of 500 kg/m³.

Gas silicate block d600

Gas silicate block d600 is used in the construction of load-bearing walls of a house. It is also recommended for use in the construction of ventilated facades, which are well attached to blocks of such density. Gas silicate block d600 has a strength of 2.5-4.5 MPa and has a thermal conductivity of 0.14-0.15 W/(m°C)

Gas silicate block d500

Gas silicate block d500 is most popular for low-rise (up to 3 floors) construction. This variety is also used in monolithic construction. Its parameters are 2-3 MPa (strength) and 0.12-0.13 W/(m°C) (thermal conductivity).

When building a house higher than three floors, you should give preference to gas silicate with a marking higher than D600 and additionally insulate the walls. Based on the value of the thermal conductivity coefficient, we can conclude that the d500 gas silicate block is 15-17% warmer than the d600 gas silicate block.

Gas silicate block d400

This type is used for arranging insulation and for working with openings during the construction of multi-storey buildings using the monolithic method. The D400 brand is also popular in private construction. With high strength, it has great heat-insulating properties. These indicators are in the range of 1 MPa to 1.5 MPa (strength), 0.10-0.11 W/(m°C) (thermal conductivity).

Gas silicate block d300

Brand D350 can only be used as insulation. This is a rather rare brand on the domestic market, due to its fragility. Strength is in the range of 0.7-1.0 MPa. But it differs in thermal conductivity, which is 0.08-0.09 W/(m°C).

Thermal conductivity of gas silicate blocks

Depending on the proportions of the starting ingredients, you can get a product with different performance characteristics. The thermal conductivity coefficient of a gas silicate block depends on its density and is determined by the marking: D300, D400, D500, D600, D700.

The thermal conductivity of gas silicate depends on a number of factors:

1. Dimensions of the building block. The greater the thickness of the wall block, the higher its thermal insulation properties.
2. Ambient humidity. Material that has absorbed moisture reduces its ability to store heat.
3. Structure and number of pores. Blocks that have a large number of large air cells in their structure have increased thermal insulation properties.
4. Density of concrete partitions. Higher density building materials retain heat less well.

Thermal conductivity table for gas silicate blocks

Types of gas silicate blocks

By appearance There are several configurations of the gas silicate block. The classification is based on the purpose of the block.

• Smooth (straight) gas silicate block with hand grip

An absolutely smooth rectangular gas silicate block with recesses for gripping by hand. The gripper is easy to use because it allows you to easily move the blocks. The presence of grip handles increases glue consumption, since the technology of laying gas silicate blocks involves filling all voids during the work process.

• Wall gas silicate blocks with flat edges

Regular rectangular shape reduces glue consumption, but creates difficulties in moving the block. In practice, when constructing load-bearing walls where larger blocks are used, preference is given to a block with a grip.

• Gas silicate blocks for partitions

They are blocks with flat edges. Partition blocks are thinner and lighter in weight. It's convenient to work with them.

You can cut out any designs on straight blocks using a screwdriver. But such decor is more likely to be used in finishing a site with the remains of blocks from construction rather than in the construction itself, since it is advisable to protect gas silicate with external finishing material.

• Tongue-and-groove gas silicate wall blocks

The formation of a tongue-and-groove connection system, in terms of production complexity, is classified as a high-tech block processing. Therefore, they are more expensive. However, it is justified because: it increases the speed of work, reduces glue consumption ( vertical connections do not require gluing), it becomes possible to eliminate cold bridges in places of vertical connection.

If the house is not exposed exterior decoration. It is better to apply to the joint thin layer glue with front side masonry This will provide additional insulation to the seam.

• U-shaped gas silicate blocks

The purpose of U-shaped blocks is to install hidden construction elements (for lintels and monolithic belts). According to the technology, masonry of walls made of gas silicate blocks requires mandatory reinforcement of the first and every fourth of the subsequent rows. It is precisely in order to conveniently hide the reinforcement that the voids in the U-shaped blocks are intended. After laying the reinforcing metal, the space must be filled with concrete mortar or glue. In this case, you should use more cheap material for filling.

What are the sizes of gas silicate blocks?

Of course, manufacturers produce gas silicate blocks of different sizes. However, most enterprises try to follow the established standards of GOST No. 31360 of 2007. Here are the dimensions of the finished products:

• 250*250*600.
• 250*400*600.
• 500*200*300.
• 600*100*300.
• 600*200*300.

It is important to understand that according to GOST, deviations in length and diagonal values ​​are allowed, which classify finished products into the 1st or 2nd category.

Deviations in the dimensions of gas silicate blocks reduce installation time due to the absence of the need for grinding and adjustment.

• Thickness of gas silicate blocks: 200, 250, 300, 350, 375, 400, 500 mm;
• The thickness of the partition blocks is 100-150 mm;
• Length of gas silicate blocks: 600, 625 mm;
• Height of gas silicate blocks: 200, 250, 300 mm;
• Weight of gas silicate blocks: 14-34 kg;
• In 1 cubic meter from 13 to 33 pcs. (depending on thickness);
• Consumption per 1 sq.m. walls is 6.7-7 pcs.

The exact parameters are shown in the tables below:

Dimensions of a U-shaped gas block Dimensions of a gas silicate block for walls (LxWxH) different manufacturers and the number of pieces on the pallet.

Number of blocks in a pallet

Weight of gas silicate block

The structural mass of the block varies depending on the density of the finished product. Judging by the markings, we can distinguish the following weight:

• D400. Weight 5-21 kg.
• D500/D600. Weight – 9-30 kg.
• D700. Weight – 10-40 kg.

In addition to density, the fundamental factor in weight change is the overall size of the finished block.

Pros and cons of gas silicate blocks

Like any building material, gas silicate blocks have strong and weak sides. Positive characteristics include the following:

1. Gas silicate concrete belongs to the category of non-combustible materials and can withstand exposure to an open flame for up to 5 hours, without changing its shape and properties.
2. Large dimensions ensure rapid construction of wall structures.
3. The blocks have a specific low weight, which greatly simplifies the work process.
4. Only used in production natural materials, therefore gas silicate blocks are environmentally friendly.
5. The porous structure provides high thermal insulation values ​​for rooms.
6. The material is easy to process, which helps to build walls with complex geometries.

The disadvantages include the following:

1. They absorb moisture well, which reduces their service life.
2. Application for adhesion of special adhesive compositions.
3. Mandatory external finishing.

It is worth noting that gas silicate blocks require a solid foundation. In most cases, a reinforcing belt is required.

Gas silicate blocks are in great demand in residential and industrial construction. This building material is superior to concrete, brick, natural wood, etc. in many respects. It is made from environmentally friendly raw materials and is lightweight, fire-resistant, easy to use and transport. Application of this lightweight material allows you to reduce the cost of arranging a heavy reinforced foundation and thereby reduce the cost of building construction.

What are gas silicate blocks

The gas silicate block is lightweight and durable wall material, which is made from cellular concrete. The products have a porous internal structure, which has a positive effect on their heat and sound insulation properties. Such building material can be used in various fields construction industry- for the construction of country and country houses, car garages, utility buildings, warehouse complexes, etc.

How gas silicate blocks are produced

There are two main technologies for the production of gas silicate building blocks.

• Non-autoclave. With this production method, the working mixture hardens under natural conditions. Non-autoclaved gas silicate blocks have a lower cost, but have some important differences from autoclaved ones. Firstly, they are less durable. Secondly, when they dry, shrinkage occurs almost 5 times more intense than in the case of autoclaved products.
• Autoclave. Autoclave production of gas silicate requires more energy and material resources, which increases final cost products. Manufacturing is carried out at a certain pressure (0.8-1.2 MPa) and temperature (up to 200 degrees Celsius). The finished products are more durable and resistant to shrinkage.

Types of blocks

Depending on density, composition and functional purpose Gas silicate blocks are divided into three main categories.

• Structural. They have high strength characteristics. The density of the products is at least 700 kg/m3. They are used in the construction of high-rise buildings (up to three floors). Capable of withstanding large mechanical loads. Thermal conductivity is 0.18-0.2 W/(m °C).
• Structural and thermal insulation. Blocks with a density of 500-700 kg/m 3 are used in the construction of load-bearing walls in low-rise buildings. They are distinguished by a balanced ratio of strength and thermal insulation characteristics [(0.12-0.18 W/(m °C)].
• Thermal insulation. They are distinguished by increased thermal insulation properties [(0.08-0.1 W/(m ° C)]. Due to their low density (less than 400 kg/m 3), they are not suitable for creating load-bearing walls, therefore they are used exclusively for insulation.

Dimensions and weight

Wall blocks made of gas silicate have standard sizes 600 x 200 x 300 mm. The overall dimensions of the semi-blocks are 600 x 100 x 300 mm. Depending on the manufacturing company, product sizes may vary slightly: 500 x 200 x 300, 588 x 300 x 288 mm, etc.

The mass of one block depends on its density:

• structural blocks weigh 20-40 kg, half-blocks - 10-16 kg;
• structural and thermal insulation blocks and semi-blocks - 17-30 kg and 9-13 kg, respectively;
• heat-insulating blocks weigh 14-21 kg, half-blocks - 5-10 kg.

Composition of gas silicate blocks

Gas silicate is an environmentally friendly building material made from non-toxic raw materials natural origin. The blocks contain cement, sand, lime and water. Aluminum chips are used as a foaming agent, which helps to increase the void ratio of the blocks. Also in the production of the material, a surfactant is used - sulfonol C.

Material characteristics

Building blocks made of gas silicate have the following characteristics.

• Heat capacity. Products manufactured using autoclave technology have a thermal conductivity coefficient of 1 kJ/(kg °C).
• Thermal conductivity. Structural and thermal insulating gas silicate has an average thermal conductivity of about 0.14 W/(m °C), while for reinforced concrete this parameter reaches 2.04.
• Sound absorption. Gas silicate blocks significantly reduce the amplitude of external noise; the sound absorption index for this material is 0.2.
• Frost resistance. Material with a density of 600 kg/m 3 can withstand up to 35 freezing and thawing cycles (which corresponds to the F35 index). Products with more high density assigned frost resistance class F50.

Advantages and disadvantages of gas silicate blocks

The main advantages of gas silicate are the following.

• Ease. Gas silicate blocks weigh almost 5 times less than concrete products the same sizes. It makes it easier construction works and allows you to reduce the cost of transporting building materials.
• Effective heat and sound insulation. Due to the presence of internal micropores, high heat and noise insulation characteristics of gas silicate are achieved. This allows you to create a comfortable indoor microclimate.
• Environmental friendliness. The building materials do not contain dangerous toxins and carcinogens that can cause harm environment and human health.
• Fire resistance. Gas silicate is made from non-flammable raw materials, therefore it does not collapse under intense heating and does not contribute to the spread of flame in a fire.

How critical are the shortcomings?

Like any other building material, gas silicate has some disadvantages.

• Low safety factor. Material with low density (300-400 kg/m3) has relatively low strength characteristics. Therefore, during construction it is imperative to carry out work on reinforcing the walls.
• Smooth surfaces. The front parts of gas silicate blocks have a smooth surface with a low roughness coefficient. Because of this, adhesion with finishing materials, which complicates the process of finishing walls with plaster and other coatings.
• Low moisture resistance. Due to increased porosity, the material is sensitive to high humidity. Water and water vapor penetrate the internal micropores and, when frozen, increase in volume, destroying the blocks from the inside. Therefore, walls made of gas silicate require additional waterproofing.

Where are gas silicate blocks used?

Gas silicate blocks are used in residential and industrial construction. This material is used not only for construction load-bearing elements buildings, but also to increase thermal insulation, as well as to protect utility networks(in particular, heating ones).

The scope of application of gas silicate is determined by its characteristics, primarily density.

• Products whose density is 300-400 kg/m 3 have a low safety margin, so they are used primarily for wall insulation.
• Gas silicate with a density of 400 kg/m 3 is suitable for the construction one-story houses, garages, service and outbuildings. Due to its higher strength, the material is able to withstand significant loads.
• Blocks with a density of 500 kg/m 3 are optimal in terms of strength and thermal insulation properties. They are often used to build cottages, country houses and other buildings up to 3 floors high.

The most durable are gas silicate blocks with a density of 700 kg/m 3. They are used for the construction of high-rise residential and industrial buildings. But due to the increased density, the porosity coefficient of the material decreases and, consequently, its thermal insulation properties. Therefore, walls built from such blocks require additional insulation.

The process of building and testing blocks.

The prepared mixture is dissolved with water, a gas-forming agent (aluminum powder) is added and transferred into molds. All types of cellular concrete increase in volume several times due to the resulting voids. The powder comes into chemical reaction with a silicate mass, as a result there is a rapid release of gas (hydrogen), which evaporates into the atmosphere, and air remains in the hardened substance (concrete) in the form of many spherical cells ranging in size from 1 to 3 mm.

When removed from the mold, gas silicate blocks are still in a fairly soft state. Their hardening should only be completed in an autoclave oven at high blood pressure(0.8-1.3 MPa) and temperature (175-200 °C).

Help 1. Cellular concrete is produced by adding a gas-forming agent and/or a foaming agent, as a result of which they become aerated concrete, foam concrete or gas-foam concrete. Gas silicate, also known as gas silicate concrete, is a type of aerated concrete.

Help 2. The lime-siliceous mixture is called silicate because of the chemical element silicon in the composition of natural silicon dioxide SiO₂-sand. In Latin it is called Silicium. Application of aerated concrete blocks

Classification and types

Depending on the purpose, aerated concrete products can be of the following structural grades:

• D1000 - D1200 - for the construction of residential and public buildings, industrial facilities;
• thermal insulation D200 - D500 - for insulation of building structures and thermal insulation of equipment in enterprises (at a temperature of the insulated surface up to 400 ° C).
• The third class consists of structural and thermal insulation products of brands D500 - D900.
• For wall products made of autoclaved concrete, the limiting grade is D700.

Gas silicate blocks are usually used in the construction of low-rise buildings and houses up to 9 floors high. There is the following gradation depending on the density of the material (kg/m³):

• 200-350 - used as insulation
• 400-600 - erect load-bearing and non-load-bearing walls in low-rise housing construction
• 500-700 - build residential and non-residential buildings with a height of more than 3 floors
• 700 and above - used in high-rise buildings, provided that row spacing is reinforced

Dimensions and shape

A block is a product with rectangular cross-section and a thickness slightly less than its width. In shape, a gas silicate block can resemble a regular parallelepiped with smooth surfaces or with grooves and protrusions at the ends (locking elements) - the so-called tongue-and-groove blocks; May have grab pockets. It is also possible to produce U-shaped blocks. The blocks are produced in the most different sizes, but should not exceed the established limits:

• Length - 625 mm;
• Width - 500 mm;
• Height - 500 mm.

By permissible deviations depending on the design dimensions, wall blocks belong to categories I or II, within which a certain difference in the lengths of the diagonals or the number of edge breaks are not considered rejection defects (for more details, see GOST 31360-2007).

Characteristics of gas silicate blocks

Basic physical, mechanical and thermophysical characteristics of wall products made of cellular autoclaved concrete:

• Average density(volumetric mass). Based on this indicator, the grade D200, D300, D350, D400, D500, D600 and D700 is assigned, where the number is the value of the dry density of concrete (kg/m³).
• Compressive strength. Depending on the conditions of upcoming operation, cellular autoclaved concrete is assigned classes from B0.35 to B20; the strength of autoclave wall products starts from B1.5.
• Thermal conductivity depends on the density, and for D200 - D700 the range is 0.048-0.17 W/(m °C), while for grades D500 - D900 of cellular concrete (on sand) of other production methods it is 0.12-0.24.
• Vapor permeability coefficient for the same brands - 0.30-0.15 mg/(m h Pa), i.e. it decreases with increasing density.
• Drying shrinkage. For autoclaved concretes made on sand, this indicator is the lowest - 0.5, in comparison with others obtained in an autoclave, but on other silicas (0.7), as well as with non-autoclaved concretes (3.0).
• Frost resistance. This is the ability of a material to saturated with water able to withstand repeated alternating freezing and thawing without visible signs of destruction and without a significant decrease in strength. Depending on the number of such cycles, products are assigned classes F15, F25, F35, F50, F75, F100.

Distinctive features of gas silicate blocks

The presence of voids in the structure of gas silicate blocks (from 50%) leads to a decrease volumetric mass and, as a result, reducing the pressure of the finished masonry on the foundation. The weight of the structure as a whole is reduced compared to other (non-cellular) concrete blocks, bricks, wooden elements.

Thus, a block with a density of 600 kg/m³ weighs approximately 23 kg, while a brick of the same volume would weigh almost 65 kg.

In addition, thanks to their cellular structure, aerated concrete blocks have good sound insulation and low thermal conductivity, that is, houses built from aerated concrete retain heat better, thereby reducing the homeowner’s costs for thermal insulation materials and heating.

If you do not take into account the amount of initial investment in equipment, including an expensive autoclave, the technology for producing gas silicate itself does not require significant costs, and therefore gas silicate blogs are considered economical building materials.

Advantages (pros)

• They belong to the group of non-combustible building materials and can withstand open flames for 3-5 hours.
• With such impressive fire resistance, autoclave-hardening blocks at the same time have high frost resistance.
• Since one block corresponds in size to several bricks, while being much lighter and more precise in geometric dimensions, the laying process proceeds at an accelerated pace.
• Well processed by cutting, drilling, milling.
• Eco-friendly, non-toxic - only natural materials are used in production.
• Thanks to high vapor permeability, walls made of gas silicate blocks are “breathable”.

Disadvantages of gas silicate concrete blocks

• High water absorption can reduce thermal insulation properties and frost resistance. Therefore, the ambient humidity should not exceed 75% or protective plastering may be required.
• As strength and density increase, heat and sound insulation properties decrease.

Transportation

Gas silicate blocks are placed on pallets, together with which they are packed in shrink film. To ensure reliability and safety during transportation, ready-made transport packages are tied with steel or polymer tape.