Houses from foam blocks characteristic. Foam concrete blocks: production technology, pros and cons, types and characteristics of the material. There are options

12.05.2020

Habitual brick walls, which can be seen in multi-storey and private construction, are losing their inviolability and relevance. In the construction of residential buildings are increasingly beginning to be used building blocks made of lightweight concrete.

Such products have greater thermal insulation, are much cheaper than solid bricks, and are convenient in terms of installation. The building material has a relatively low weight, which significantly reduces the load on the foundation, respectively, allows you to save on its pouring.

The modern construction market offers the consumer several varieties of wall blocks. To avoid difficulties when choosing a material, consider the advantages and disadvantages of wall blocks used in construction.

Foam concrete blocks

This is cellular lightweight concrete, the main component of which is a cement-sand mortar with the addition of foaming additives. According to experts, this is the most practical and affordable material for the construction of wall structures, which is steadily growing in popularity.

Advantages	disadvantages
High strength combined with low density Low structural weight due to honeycomb structure Excellent thermal insulation of interiors High degree of street noise absorption Fire resistance - the material does not ignite and does not support the spread of fire Wet environment resistance Good frost resistance budget cost	Foam concrete is subject to shrinkage over time, which should be taken into account during construction Non-homogeneous structure: internal pores do not have the same size Difficulties in interior decoration - foam concrete is unable to hold conventional fasteners (nails, self-tapping screws) Low bending strength, cracks easily

The material is often produced in an artisanal way without observing the technology. It is almost impossible to determine a fake visually, so you need to responsibly approach the choice of a manufacturer.

Aerated concrete material for building walls

As in the previous case, gas silicate blocks have a porous structure. For production, a silicate base is used with the addition of binders and foaming additives.

Advantages	disadvantages
The exact geometry of each block, which simplifies the process of erecting wall structures and allows you to accurately calculate the consumption of glue. Presentable appearance. Ease of processing: you can cut aerated concrete with a regular hacksaw. High level of fire safety. Environmental safety: chemically active and toxic substances are not used in the production. The large size of the block - allows you to reduce the time for the construction of walls.	Low strength - the gas block is not used in multi-storey construction. After completion of work, shrinkage is observed up to 1.5 mm for every meter of height. According to this indicator, gas silicate blocks are considered the worst among lightweight concretes. Low frost resistance - only 10 cycles freezing/thawing. Therefore, the walls of this material necessarily need additional insulation. Humidity dependent. Aerated concrete perfectly absorbs water, which leads to the destruction of the structure of the block.

In terms of thermal insulation, aerated concrete blocks are close to solid bricks, so additional insulation is a must. However, the blocks have a minimum weight, which significantly reduces the load on the foundation.

Sand blocks made by volumetric vibrocompression

This is a universal option, equally used in multi-storey construction and the private sector. In the manufacture of building material, a cement-sand mixture is used with the inclusion of additives in the composition. Products are pressed in special forms, dried with infrared radiation.

For optimum strength, blocks are stored at room temperature in well ventilated areas.

For walls made of foam blocks, the cost of insulation will be significantly lower than for concrete or brick structures.

Heatblock - a multilayer wall element with a facing layer

This is a composite material having a three-layer structure.

The first layer is called the facade and is an imitation natural stone. The second - insulating, consists of high-density polystyrene foam. The third - supporting, is made of expanded clay concrete.

Heat blocks appeared on the construction market relatively recently, but have already gained popularity among professional builders.


High speed of building walls. Each block is both a decorative and load-bearing structure and has a layer of insulation. Excellent indicators of thermal insulation. Block, thick 42 cm similar in terms of two-meter brickwork. Acceptable cost. Good competition for gas and foam blocks. Light weight. You can significantly save on the foundation.	The weight. Blocks are considered easy, but to cope alone with laying stones, weighing 24 kg, will be difficult. Low resistance to dynamic loads. Not suitable for buildings high more than 3 floors. Geometry. The correct forms are found only from trusted manufacturers. If the block is made in a handicraft way with laying, there are guaranteed to be problems.

High-quality heat blocks have absolutely correct geometry, therefore it is allowed finishing without additional alignment of the walls. During the installation of blocks, through joints are formed that need high-quality sealing.

If the construction technology is violated, high thermal efficiency indicators will be reduced to zero.

Polystyrene concrete

The block is a monolithic structure, where the main component is high-quality cement. Quartz sand, foamed polystyrene, plasticizers are used as a filler, which increase the strength and frost resistance of finished products.


The best thermal insulation on the market. Allows to save on heating of internal rooms in the winter period. High strength. The material is highly resistant to compression and bending, and has virtually no shrinkage. Excellent vapor permeability. The walls of such blocks have the ability to "breathe", which is guaranteed to prevent the appearance of mold. Ease of installation. The blocks are easily subjected to additional processing, have a large size and the correct geometry. Frost resistance. The product can withstand up to 150 cycles freezing / thawing without loss of original properties.	Direct dependence of quality from the manufacturer. Violation of manufacturing technology leads to the formation of internal microcracks. Difficulties interior decoration. The surface of the block has poor adhesion with plaster solutions. The porous structure "does not hold" nails and self-tapping screws.

Polystyrene concrete blocks are considered a non-combustible material, but when exposed to high temperatures, they begin to release phenol, a substance harmful to human health.

Expanded clay concrete - actual material comes from the 60s of the last century

The composition of such a block includes cement, expanded clay and sand, mixed in predetermined proportions. In the manufacture, the vibrocompression method is used, which provides finished products with a fairly dense structure.

Despite the obvious disadvantages, expanded clay blocks are considered the most common building material in Russia.

Arbolit - material from wood chips and mineral binder

Composite blocks created on cement base with the addition of water, sand and sawdust. This ratio of components makes the unit resistant to any aggressive environment, while finished goods have a high margin of safety.


Thermal insulation. analogues wood concrete blocks not yet available on the building materials market. Ease of installation and manufacture. You can handle the work on your own. Environmental Safety. The composition does not contain harmful and toxic components. Minor weight. There is no need for a reliable and solid foundation. Democratic price. Considered one of the most available materials On the market.	Destroyed by prolonged exposure to a humid environment. Attract rodents. Due to the inclusion in the composition of wood, the material burns.

Blocks are not suitable for multi-storey construction, intended use: private sector.

Cinder block - it can't be cheaper

The material attracts the attention of buyers with a surprisingly low price: the use of production waste is allowed in the manufacture. Products are compacted by vibrocompression, the main binding component is cement.

Unlike previous materials, cinder blocks are hollow and monolithic, which greatly expands the scope of their application.

Advantages	disadvantages
Absolute incombustibility even at long influence of high temperatures. Long service life - at least 50 years old without losing original qualities. Wide range of. The variability of fillers allows you to choose a product for any type of construction work. Ease of installation. Ability to make at home.	Humidity dependent. It causes inconvenience when summing up engineering communications. Low rates of sound and heat insulation. Lack of environmental safety: the slag contains sulfur and acids that are harmful to health.

Given the significant drawbacks, cinder blocks are more suitable for the construction of utility structures than residential buildings.

Keramoblock - a worthy replacement for hollow bricks

Great alternative to regular brick. Blocks appeared on the market relatively recently, but are rapidly gaining popularity in the private construction sector. The block is based on burnt clay, finished products have a hollow, cellular structure.

Advantages	disadvantages
Absolute environmental safety. Excellent indicators of thermal insulation. Minor weight. High vapor permeability. Reliable soundproofing of internal premises. Ease of installation: the elements are joined by a tongue-and-groove locking connection.	Overcharge. Unreliable ends. Relative fragility, which makes it difficult to transport. Dependence on strict adherence to laying technology. Difficulties in interior decoration: the hollow structure will not "hold" screws and nails.

Difficulties may arise during additional processing: it will not work to split a ceramic block like an ordinary brick, you will have to use a grinder.

Heat-efficient Balaev blocks

A relatively new building material resembling heat blocks. Products have a three-layer structure:

filler;

Cement, lead and expanded clay are used as the main components. In the manufacture, vibrocompression technology is used in combination with the clamping method. The result is a fundamentally new building material.

The material is on the market in 2009, therefore, did not have time to manifest itself from the negative side. However, the obvious disadvantages can already be attributed to the high cost.

Specification comparison table

Comparison of blocks by construction cost

Often, the price issue is the key when choosing a building material. The diagram above shows the comparison of block prices relative to each other in percentage terms. The most expensive block of Balaev was taken as 100%.

Depending on the region of the country, and over time, this ratio may change.

Block cost is not a key indicator. For example, Balaev blocks are the most expensive material, but they do not need additional finishing and warming. The final estimate of the work performed will be much lower than when building walls from expanded clay concrete blocks.

Brief conclusion

Ideal building materials does not exist in nature. Therefore, when choosing building blocks, you need to focus not only on the price of the product, but also on the scope and technical characteristics.

The best thermal insulation properties of all building materials for the house is wood, and the most durable and fireproof is stone. Attempts to connect beneficial features wood and stone, in the end, and allowed to create a series modern materials, one of which is foam concrete.

Porous concrete

The thermal insulation properties of the material, as a rule, are given by its structure, or rather, the amount of air that is held inside. Mineral wool, fiberglass, foam plastic, polystyrene - they are all characterized by a fibrous or cellular structure. The air contained in the pores just gives the material thermal insulation properties.

Foam concrete is identical in composition to ordinary concrete, but is produced by a different method. In its manufacture, foaming additives are used that form a cellular structure. Unlike aerated concrete, foam concrete is characterized by closed pores, which reduces the vapor permeability of products made from it, but also contributes to a higher resistance to moisture.

Foam concrete is characterized by the qualities of both wood and stone.

Strength - depending on the density index, products can be used in different capacities: from a heat-insulating layer to a structural material.
Lightness - low compared to ordinary concrete or brick. Density gives foam blocks greater lightness, which, in turn, contributes to a significant simplification of the work of builders and a reduction in the period of work.
Thermal insulation - depends on the density of the material, and its range allows you to choose a foam block with the required thermal conductivity.
Fire safety - the material is non-combustible and is absolutely safe.
Inertness is very high, both in relation to chemical aggressive environments, and in relation to biological ones - mold, fungi, rot, and the like.
Affordable cost is also one of the very important user qualities.

The foam block differs in only one negative feature - low mechanical strength. Therefore, during the construction of a house, especially from large blocks, care should be taken.

What products does the market offer?

For a long time, the foam block was produced in almost a single size: 200 * 300 * 600 mm. The parameters were considered standard, and the foam block was called universal and was used equally for the construction of both external and internal partitions of the house.

To date, there are no standard sizes as such. The specified “universal” is still the most popular, however, the release of foam blocks with other parameters made it possible to divide the products into groups.

For the construction of the outer walls of the house, experts recommend using larger blocks. On the one hand, this facilitates the work of the builder, especially since the outer walls of the building should consist of two rows of foam blocks, on the other hand, big sizes reduce the number of vertical seams, which in turn contribute to the formation of cold bridges. Product parameters: 250*400*600 mm, 250*375*600 mm. Which dimensions are optimal is determined by the builder himself.

The large dimensions of the block not only speed up the construction of the house, but also helps to reduce other costs. For fixing it, a smaller amount of cement is required, for finishing - a smaller amount of plaster. The alignment process is also facilitated, as fewer elements need to be adjusted. If the dimensional parameters do not match, the blocks are very easy to correct: the material is sawn and polished without the slightest difficulty using mechanical tools.

For internal partitions, foam blocks of smaller dimensions are used: 100 * 250 * 600 mm or 125 * 250 * 600. As a rule, blocks with a minimum height of 75 * 250 * 600 mm are used for walls in bathrooms. This is due to the fact that the inner walls of the house are much thinner than the outer ones, but at the same time they should have a smoother surface.

The video demonstrates the use of foam blocks.

Density and thermal insulation

An equally important issue in the construction of a house is the thermal conductivity of the material associated with its density. Which foam blocks to choose for construction depends on the purpose of the building and the area of residence.

Material with a density index up to 500 kg / sq. m. is a good heat insulator, and is recommended for appropriate work. However, its strength is insufficient and it is impossible to build a load-bearing wall from it.

Foam block with a density in the range of 500–900 kg / sq. m. withstands very significant loads and can be used for construction external walls Houses.
Product with a density of 900 to 1200 kg/sq. m. is applied without restrictions. However, its thermal insulation properties wish the best. In the photo - samples of materials with different densities.

Foam blocks have high thermal insulation, are light in weight and have sufficient strength. Due to these qualities, they are increasingly used in construction. It is very important to choose the correct weight, density, dimensions of foam blocks for bearing walls.

Consider the types and characteristics of the material, standard dimensions, what you need to pay attention to when buying, how to calculate the number of blocks in 1 cubic meter.

Properties of foam blocks

Foam blocks can withstand from 15 to 75 freezing cycles

To purchase quality material to build a house, you need to study its main characteristics:

Density is determined by the ratio of the mass of a material to its volume. Foam blocks are marked with the letter D and numbers, the higher the number, the higher the density of the material.
Resistance to sub-zero temperatures, the indicator is determined by the number of freeze and thaw cycles. This material is able to withstand, depending on the brand, from 15 to 75 cycles.
The mass is determined by the density of the material in the block at normal humidity levels. The foam block weighs from 8.5 to 47 kg.

Wall blocks are selected depending on the parameters of the future building and the climatic conditions in which it will be operated.

Scope of application

Foam blocks can also act as a heater

Foam concrete blocks can be used:

as a heater for walls and floors, heat-insulating blocks of the brand from D 150 to D 400 are used;
installation of partitions and walls that do not perform the function of bearing, perform structural and heat-insulating material grades D 400, D 500;
construction of load-bearing external and internal walls and floors are made with structural foam blocks of grades from D 600 to D 900, suitable for mounting buildings on 1-3 floors;
for buildings with a height of more than 3 floors, structurally porous foam blocks of the grade from D 1000 to D are used

It is important during construction to choose the best material grade in terms of price-quality ratio.

Kinds

Grades of foam concrete blocks lower than D400 are not subject to rationing by strength class. Most often they are used to insulate walls that do not have a load-bearing load.

Types depending on the production technology:

Consider in the table the classification of wall blocks by grade and their characteristics:

brand	Coefficient of thermal conductivity	Weight, kg	Strength per cm3	Frost resistance	Application
D400	0.12 W/mºС	11	9 kg	Not standardized
D500	0.12 W/mºС	19,4	13 kg	Not standardized	For insulation of interior walls
D600	0.14 W/mºС	23,3	16 kg	15-35
D700	0.19 W/mºС	27,2	24 kg	15-50	For the installation of load-bearing walls in low-rise buildings (up to 3 floors)
D800	0.24 W/mºС	31,7	27 kg	15-75	For the installation of load-bearing walls in low-rise buildings (up to 3 floors)
D900	0.29 W/mºС	35,6	35 kg	15-75	For the installation of load-bearing walls in low-rise buildings (up to 3 floors)
D 1000	0.36 W/mºС	39,6	50 kg	15-50
D 1100	0.36 W/mºС	43,6	64 kg	15-50	For installation of ceilings and load-bearing walls
D 1200	0.36 W/mºС	47,5	90 kg	15-50	For installation of ceilings and load-bearing walls

The strength of the blocks depends on the temperature and humidity at which foam concrete is produced. An approximate indicator of strength (with a margin) can be found by dividing the brand number by 20. Material with a frost resistance of 15-75 can be used in the northern regions.

Block sizes

Foam concrete blocks are most often made in standard sizes. Each size corresponds to the purpose of the material:

Some manufacturers produce blocks in sizes: 200x200x600, 200x400x600, 240x300x600, 80x300x600.

Consider, based on the table, the dimensions of the foam blocks for the construction of load-bearing walls of the D 600 brand and the weight of one piece of material:

Dimensions	Weight of one piece, kg	Number of pieces per cube. m
80x300x600	8,5	70
100x300x600	11	56
200x200x600	14	42
160x300x600	17	35
200x300x600	22	28
240x300x600	25	23
200x400x600	28	21

Blocks of grades D 1300-1600 for multi-storey construction can be made to order according to individual sizes.

Compound

The constituent components of high-quality foam blocks are determined according to GOST "cellular concrete" 25485-89.

Composition of foam blocks

The mixture must contain at least 70% silicate

The composition includes such components:

Portland cement containing in its composition 70-80% calcium silicate;
sand with a content of 75% quartz, silt and clay impurities should be less than 3%;
water corresponding to TU and GOST 23732-79;
synthetic and natural foaming components: caustic technical sodium, scrubber paste, skin glue, pine rosin, bone glue.

The addition of synthetic components allows you to get cheaper products with insufficient environmental safety and less strength. When using natural components, the cost of production increases, but the material is obtained fully meeting the requirements.

Advantages and disadvantages of foam blocks

Foam concrete blocks have many advantages over other materials:

heat saving indicators are 3 times higher than those of bricks;
environmentally friendly;
the material is light, in comparison with expanded clay concrete, has a weight 2.5 times less;
not subject to rotting and deterioration from atmospheric and biological influences;
frost resistance, due to the porous structure, does not change its shape with sudden changes in temperature;
withstand exposure to open flame for 4 hours;
easy to process, easy to cut, can be made directly on the construction site.

The disadvantages include:

the possibility of shrinkage during operation with high humidity;
able to absorb moisture, therefore, finishing with moisture-resistant plaster or water repellent is required;
nails will not hold in the walls of foam concrete blocks; special dowels must be used. For more information about the pros and cons of the material, see this video:

For complete drying and strength gain, foam concrete blocks must stand in dry rooms for 28 days.

Calculation of the number of blocks

Consider how to calculate how many blocks are in 1 cubic meter.

For example, let's take a wall block measuring 200 x 300 x 600 mm.

It is necessary to calculate the volume of one block by multiplying the dimensions of the sides: 0.2 * 0.3 * 0.6 = 0.036 m3.
We calculate how much material in 1 cu. m. by dividing: 1/ 0.036 \u003d 27.7 pieces. Round up to 28 pcs.

How to get quality material

Cells must be sealed

In order for the building to serve for a long time, you need to take a very responsible approach to the choice of building materials.

What to look for:

Availability of certificates and other related documentation.
Production must be carried out in a heated covered room.
Cells must be sealed. If you split a block, its structure should be the same inside and out. Cells should be round without chips or cracks.
The color of foam concrete blocks should be grayish, uneven coloring is allowed.
An important role is played by the correctness of the geometric shapes of the wall blocks. This can be checked by placing blocks on top of each other. They should fit snugly and not wobble. It is better to check the geometry of the material in advance from all sides.
The material is fragile, so it must be transported and unloaded carefully.
To prevent the appearance of cold bridges, the blocks can be mounted on a special glue. The seam in this case is 2-3 mm.
If you are lining foam concrete blocks with bricks, leave a gap between the materials, as they have different air permeability. For more information on how to build a house from a foam block, see this video:

The material is divided into 2 grades:

Grade 1 meets the requirements of GOST, it includes high-quality material with the correct geometry;
in grade 2, small chips are allowed on the surface and in the corners.

If you're not sure you're getting aged material, then leave it in a dry room for 3-4 weeks to dry and complete set strength.

Foam concrete blocks are a high-quality material with many advantages. Knowing its basic parameters will allow you to choose the best suitable material for any climate zone.

As soon as possible. This material has conquered domestic builders with its operational qualities, therefore its range and the number of manufacturers is constantly growing. Unfortunately, the percentage of foam blocks produced in a handicraft way without taking into account any standards is also increasing, so it is becoming increasingly difficult to choose high-quality material. Which foam blocks are suitable in each case and what to look for when buying to get really high-quality, strong and durable material?

No. 1. Features of the production of foam blocks

The basis of the foam block is cement, sand and water. To carefully add a special foam, which is usually obtained on the basis of surfactants or foam concentrate. A homogeneous mass is cut or laid out in molds, leaving to solidify in the open air or in an autoclave.

Not the most difficult process production allows dubious firms to manufacture foam blocks, which led to the flooding of the market with products that do not comply with GOST. Factory packaging in polyethylene film, the presence and markings indicating the density, purpose and permissible errors in size indirectly indicate the integrity of the manufacturer.

AT general scheme There are some differences in the production of foam blocks, which for the most part relate to the formation of individual blocks, on which the quality and geometry of the product depend. According to the manufacturing technology, foam blocks are divided into the following types:

Foam blocks are often confused with aerated concrete.. What are the differences? The main one is hidden in the composition. For the manufacture of a foam block, a mixture of cement, sand and water is used, and the blowing agents are different. Instead of special foam, lime and aluminum dust are added to aerated concrete, as a result of the interaction of which hydrogen is released, foaming the mass. The internal structure is also different: aerated concrete has solid pores. In addition, it necessarily undergoes heat treatment, which is why it costs more.

No. 2. Advantages and disadvantages of foam blocks

If the foam block is made with high quality and in compliance with all requirements, then it receives a lot of excellent performance, for which it has gained such significant popularity.

The main advantages of foam blocks:

The main disadvantages of the foam block:

Foam blocks have more advantages than disadvantages, and if you choose right stuff, then the construction will be durable and reliable. You can build from foam blocks . To increase the strength, it is recommended to reinforce the walls.

No. 3. The size of the foam blocks

The first thing to consider when buying a foam block is its size. Today, almost all manufacturers produce foam blocks of this size:

All foam blocks in a batch must be strictly the same size.- this is a guarantee that they will fit exactly to each other. A pre-purchase check can be done by measuring the dimensions of the blocks and comparing them, or by placing the blocks on a flat surface, so you can compare the sizes of the products and see how closely they fit together. The presence of gaps and steps on the surface of the blocks is not allowed - this will not only increase construction costs, but can also lead to the formation of cold bridges.

No. 4. Density and frost resistance of foam blocks

Density is a key characteristic of foam blocks. According to this parameter, one or another brand is assigned to the material. Density is indicated by the letterD, foam blocks of brands are presented on the market fromD400 toD1200 . For different purposes, foam blocks with different densities are used:

With an increase in density, the thermal insulation characteristics of the blocks fall, as the amount of air trapped in its structure decreases.

Another characteristic of foam blocks - frost resistance, i.e. the number of freeze and thaw cycles that a material can withstand without changing its properties. This indicator is marked letterF followed by a number indicating the number of freeze/thaw cycles allowed. This indicator ranges from 15 to 75. The highest level of frost resistance is suitable for areas with extremely harsh climates.

No. 5. The structure of the foam block

No. 6. What else to consider when externally inspecting the foam block?

Since the production of foam blocks does not require special equipment, today the number of unscrupulous entrepreneurs offering products that do not comply with GOSTs is growing, so it is becoming increasingly difficult to choose a really durable and high-quality material. During an external examination of the foam block, it is worth focusing on such signs of quality material:

And finally better trust, appearing on the market for a long time - so there is a higher guarantee that the constructed structure will be durable, and the foam block will meet your expectations.

The foam block is a porous stone, a kind of cellular concrete. The concept of foam concrete and aerated concrete is often confused, considering them identical.

What is the difference between a foam block and a gas block? In principle, the difference lies in the names of these materials.

The foam concrete block is made by mechanical mixing of a mixture consisting of sand, water, cement and prepared foam. BUT aerated concrete block formed with the help of gas (hydrogen), which is released during chemical reactions. In this regard, through pores are formed in aerated concrete, and closed ones in foam concrete, which gives its waterproofing properties higher characteristics.

The composition of the foam block

Foam concrete blocks are a breathable material that creates the same microclimate in the room as wood. What component composition allows you to achieve such comfortable parameters?

Foam concrete mixture, according to GOST 25485-89 "cellular concrete" consists of:

1. The binder component of the mixture is Portland cement, manufactured according to GOST 10178-85, with a calcium silicate content of up to 70-80%.

2. Sand, must meet the requirements of GOST 8736-93, with a quartz content of at least 75%, clay and silt inclusions no more than 3%.

3. Water with technical requirements according to GOST 23732-79.

4. A foaming agent is used based on:

bone glue that meets the requirements of GOST 2067-93.
pine rosin - according to GOST 19113-84.
skin glue - according to GOST 3252-80.
scrubber paste - according to TU 38-107101-76.
caustic technical soda - according to GOST 2263-79.

Foaming agents, according to the basis used, are divided into:

Synthetic foam concentrates . They allow you to get inexpensive products, but the blocks of them are not of such high quality and durable. Moreover, they have a hazard class 4, that is, their use can harm human health.
natural blowing agents have an environmentally friendly basis, without a hazard class. The product becomes more durable, as the interpore partition is thicker.

It is advisable, before buying blocks, to take an interest in the basis that goes for the production of a foam concentrate.

Some manufacturers began to use other components for the production of foam concrete blocks:

Polypropylene fiber VSM (building fiber, micro-reinforcing). The use of HCM makes it possible to obtain a product with precise, non-destructive edges, and to increase its compressive strength up to 25%.
fly ash . It is the ash that is formed when burned. solid fuel at TPP. It is a finely dispersed material, with a particle size from fractions of a micron to 0.14 mm. Its use leads to a denser and harder pore wall and a 30% cement savings.

Types and characteristics of the foam block

By changing the percentage of ingredients in the composition of the foam concrete mixture, you can get different characteristics foam concrete. For example, the less sand, the higher the strength of the product.

The main physical and mechanical properties of blocks:

1. By density, foam concrete blocks are divided into the following types:

Structural: grades D1000, D1100, D1200. They are used for the construction of foundations, basement floors of buildings, load-bearing walls.
Structural and thermal insulation: grades D500, D600, D700, D800, D900. It can be used for the device of partitions and load-bearing walls.
Thermal insulation: grades D300, D350, D400, D500. This type of foam block is designed for the heat-insulating contour of the walls.

2. The thermal conductivity index depends on the purpose of the block:

Structural grades have thermal conductivity from 0.29 to 0.38 W/m °C, which is lower than the thermal conductivity of clay bricks.
Structural and heat-insulating – from 0.15 to 0.29 W/m °C.
Thermal insulation – from 0.09 to 0.12 W/m °C. For comparison: the thermal conductivity of wood varies from 0.11 to 0.19 W / m ° C.

3. Frost resistance of foam blocks is quite high. The fact is that in its micropores, water is in a bound state, and does not turn into ice, even if it is very cold outside. low temperature. It is equal to: 15, 35, 50 and 75 cycles.

You can always choose a block with the desired strength and frost resistance. Foam concrete with frost resistance F75 can be used in the northern regions.

4. According to the manufacturing method:

Cut block: a large array of foam concrete is cut to the specified dimensions by a special cutting complex. Such products have the best geometry and edge integrity, but the quality of these indicators is highly dependent on the integrity of the manufacturer.
Form block: foam concrete mixture is poured into a mold with partitions. It is cheaper than cut.

Dimensions and weight of the foam block

According to the purpose, the foam concrete block is distinguished:

Wall block. Standard foam block size: 600×200×300 mm (length; depth; height)
Wall block. Its size: 600×100×300 mm.
Many manufacturers, based on the wishes of the customer, produce products with other volumetric characteristics: 80 × 300 × 600mm; 240×300×600mm; 200×400×600mm; 200×200×600mm.

How much does the foam block weigh? Its weight directly depends on the density of the product, the manufacturer and is approximately equal to:

The weight of the structural wall block ranges from 39 kg to 47 kg. Semi-block - from 19 kg to 23 kg.
The weight of the structural and heat-insulating block varies from 23 kg to 35 kg. Semi-block - from 11 kg to 17 kg.
The weight of the heat-insulating block is from 11 kg to 19 kg. Semi-block - from 6 kg to 10 kg.

Advantages and disadvantages of the foam block

The advantages of this wall material do not take:

Durability and strength. This is a practically eternal material, the bearing capacity of which does not decrease with time. Some brands of foam blocks are allowed to be used for the construction of houses up to 3 floors high.
The fire resistance of foam concrete is very high (masonry with a thickness of only 15 cm can withstand an open flame for almost 4 hours without destruction).
Low water absorption of the material provides it with high frost resistance (up to 35 freeze-thaw cycles).
Low thermal conductivity. For comparison: a wall in one foam block (200mm) will retain heat in the same way as Brick wall, 60-70 cm thick.
Low density reduces transportation costs, simplifies material handling, shortens construction time and exerts low pressure on the building foundation.
In terms of environmental friendliness, it is second only to wood. For a tree, the coefficient is 1, for a block of foam concrete it is 2, and for a brick it is already 10.
High sound insulation. For example, blocks with a thickness of 100 mm completely absorb noise from 41 to 43 dB.
Relatively "democratic" cost.
The period of active precipitation lasts 28 days. In the future, its value is insignificant.

Disadvantages of foam blocks:

In order not to worsen the performance in terms of sound insulation and thermal conductivity, it is desirable that the width of the mortar joints be no more than 2 mm. Even better - plant them on a special glue. It is clear that in this case, the geometry of the products should be almost perfect. Not every manufacturer can boast of this.
The need for finishing to give the house construction an aesthetic appearance.
It is advisable to take a responsible approach to the choice of the manufacturer. Violation technological process leads to brittleness of the material.

True, the choice of a conscientious manufacturer must always be carried out. Regardless of what you buy.

How much does a foam block cost?

Depending on the contractor and the brand of the product, the price per piece of the foam block is:

Wall, structural and heat-insulating block on average from 120 rubles. up to 140 rubles
The same semi-block is equal to about 60-75 rubles.

The cost of 1 m3 of products for this purpose is from 3200 rubles. up to 3800 rub.

Accordingly, the cost of a heat-insulating block is slightly cheaper, and a structural one is slightly more expensive than that of the above-described foam concrete product.

For curious builders

Despite the active promotion of foam concrete on the market, not all manufacturers can provide it with the proper quality. In order to understand what an ideal foam block should be, we will have to delve into the field of building physics and chemistry.

The cellular structure with a uniform distribution of foam bubbles is the basis of the heat-saving properties of foam concrete. To create it, it is not enough just to mix the foam with cement mortar. If this is done, then we will get porous concrete with a density of 750 kg/m3. This material is durable, but not warm enough.

If we reduce the amount of cement and sand and add more foam, the density of the concrete will decrease to the required value. However, this will seriously disrupt its structure. It will not become less mechanically strong, but will lose a significant part of the closed pores, which will unite into through channels. As a result, the material will change its structure, increase water absorption and turn into aerated concrete. Therefore, all handicraft industries, which are based on three units: a foam generator, a mortar mixer and a mixer, are not capable of producing high-quality foam concrete blocks with a density below 750 kg/m3.

The optimal structure of foam concrete of a heat-insulating class (from 300 to 500 kg/m3) can only be obtained using modern equipment that operates using the vibroexpansion technology. Its main difference from the old methods is the combined formation of pores in concrete. To do this, not only air-entraining (like foam concrete), but also gas-forming (like aerated concrete) additives are introduced into the mixture.

Thanks to vibration, the same size of closed pores is achieved and there is an additional strengthening of the power "framework" of the material. Shrinkage of finished blocks obtained by this technology is minimal, which is also a positive moment for construction. new material was called aerated concrete.