Aerated concrete is a porous building material made on the basis of siliceous aggregate and a cementitious component. It acts as one of the varieties of lightweight concrete. The material is used for thermal insulation, insulation of reinforced concrete floors and attics, as well as in the role of an insulation layer of wall structures of buildings for various purposes. It can be used for thermal insulation of surfaces of pipelines and equipment at temperatures up to 400 degrees.
Recently, cellular concrete is gaining popularity as a structural wall material. Private houses and multi-story buildings erected from it have higher thermal characteristics compared to brick ones. This was achieved thanks to the correct geometry of modern blocks, due to clear dimensions, the deviation from the standard of which can be 2 millimeters in both directions. Products can be laid on special glue, which allows you to form seams with a thickness of not more than 3 millimeters.
If we consider blocks made of cellular concrete, then they should be divided according to their functional purpose. They can be heat-insulating, while the bulk density varies from 300 to 500 kilograms per cubic meter; structural and heat-insulating (the mentioned parameter is in the range from 500 to 900 kilograms per cubic meter); as well as structural - their bulk density is not more than 1200 kilograms per cubic meter. The last of these materials is used for the construction of agricultural buildings and structural elements for residential use.
Characteristics of non-autoclave foam concrete blocks
As one of the varieties of cellular concrete products are foam blocks that are able to retain heat well. If we compare with a brick, then this material has a 3 times lower thermal conductivity coefficient. The weight of these products is negligible, compared with expanded clay concrete, it is 2.5 times less. Aerated concrete blocks are easy to transport and assemble, this is their advantage over conventional building materials.
Using them, you can build houses without equipping the first stage with a heavy, deep foundation, which positively affects the speed and simplicity of construction. We are talking about low-rise buildings, while in high-rise buildings, the foundation must still be solid. Blocks of foam concrete are worthy of durability. For example, from products of the D900 brand, load-bearing walls of three-story houses can be laid.
Positive features of foam concrete blocks
Aerated concrete blocks are resistant to frost. Inside there is enough space for water, which can expand freely when freezing, without damaging the structure of the products. That is why at low temperatures there will be no bursting inside and out. Foam concrete is chosen because of its fire resistance. Under the influence of open fire, the material can remain for 4 hours, while it will not be damaged, the structure will not be covered with cracks and explosions will not occur.
Biostability and environmental friendliness are also on top. Foam concrete blocks do not rot, and eventually do not deteriorate at all. During installation and operation, foam does not emit harmful substances. Compared to gas silicate, the latter is less safe in this regard. This is because in the autoclave, when foaming, the small elements of aluminum and lime react, resulting in the formation of hydrogen. It is released in a small amount later, while foamers are used for the production of foam blocks, which do not contain hazardous gases. The pores of this material are hermetic, therefore, in structure they resemble foam cells.
For reference
Aerated concrete blocks can be used in the construction of monolithic buildings. They are made on site, for this it will be enough to use special equipment. With the help of the compressor, pressure is created, and the material is transported to the place where construction work is carried out.
Ease of processing
It is very simple to process foam concrete; it is easy to crush, cut and drill. Special tools for this are not required, as well as physical effort. Due to its lightness, the material can be transferred from place to place, which makes it possible to carry out construction work by one person.
The cost of foam concrete blocks
Wall blocks made of foam concrete are quite affordable. If we compare with other building materials, their price will be significantly lower. If you take into account that during the construction of the house a light foundation will be laid, then the work will be financially economical. For some consumers, this factor is crucial. Thus, cellular concrete (blocks), the price of which is 89 rubles. per unit, have the following dimensions: 600x300x200 millimeters. For a cubic meter you will have to pay 2500 rubles. With dimensions of 600x300x250 millimeters, the price rises to 112 rubles apiece. When resizing to 600x400x200, one product will cost 120 rubles.
Characteristics of aerated concrete blocks
If you are interested in aerated concrete wall blocks, then you can consider the characteristics of gas blocks, which have outstanding qualities. Despite the lightness, the material has high strength. Aerated concrete is considered a compromise between optimal thermal insulation, strength and lightness. Depending on the brand, the compressive strength can vary from 1.5 to 3.5 kgf / cm 2 . Aerated concrete blocks of grades D600 and D500 are successfully used as heat-insulating and structural material.
Products have low thermal conductivity, which allows the walls to provide reliable thermal protection even in the coldest time. In the summer, buildings made of aerated concrete do not overheat, while the optimum temperature is maintained inside. Like foam concrete, aerated concrete is flame resistant. Houses and enclosures built from it belong to the highest degrees of fire safety.
Dimensions of cellular concrete blocks
Blocks of cellular concrete (GOST 21520-89) can be wall and partition. In the first case, the sizes vary from 400x200x200 millimeters to 600x500x200 millimeters. If we are talking about partition products, then the sizes range from 300x400x150 to 600x400x100 millimeters.
Masonry blocks
Masonry from aerated concrete blocks should begin after waterproofing the base, which is carried out by any suitable roll materials, for example, bicrost. Before mounting the first row of blocks, it is necessary to apply a layer of mortar or adhesive, only after which you can start laying. The dimensions of the waterproofing layer should be slightly larger compared to the width of the foam concrete block. Regardless of whether you will use a cement mortar or adhesive during the laying process, laying the first row is carried out on a traditional mixture of cement and sand. It is worth remembering that small blocks of cellular concrete will slow down the construction process.