Aerated concrete or foam concrete, which is better: characteristic features, how aerated concrete differs from foam concrete. Foam concrete or aerated concrete - what to choose for building a house? Aerated concrete and foam block, which is better?

A fairly common question on the Internet is aerated concrete or foam concrete, which is better? Why does he care so much land owners who Are you developing a project for your future home and deciding on the choice of materials for its construction? How fundamental is the difference between these very similar materials?

It should be immediately noted that both aerated concrete and foam concrete belong to the group of cellular concrete, that is, building materials that have in their structural structure many tiny air cavities that reduce the density and increase the thermal insulation qualities of the blocks. What unites them general concept"gas silicates". However, these materials still differ significantly from each other in their characteristics, which should be studied before choosing one.

Production of building materials from cellular concrete

To understand the differences between aerated concrete and foam concrete, it is first worth considering their production technology. The fact is that it is during the manufacture of the material that its specific qualities are formed.

Production of aerated concrete

Aerated concrete is an artificially created mineral that has a uniform cellular structure.

Thanks to its structure, gas concrete blocks They are characterized by their low weight, so the construction of the walls of a house or other structures can easily be carried out without the use of lifting equipment. The blocks lend themselves well to processing, and if necessary, reduce their size - the material is easy to saw hand hacksaw. In some cases, to speed up this process, a grinder or an electric jigsaw can be used.

The manufacturing process of aerated concrete blocks is as follows:

Materials prepared in certain proportions (sand, cement, lime) are poured in and mixed dry in a special mixer for 4-5 minutes. Then a water-based suspension of aluminum powder is added there.
During the mixing process, lime enters into an active reaction with aluminum, resulting in the formation of free hydrogen. Due to the abundant gas formation throughout the entire volume of the mixture, bubbles with a size of 0.5 to 2 mm appear in the raw material mass, which are evenly distributed in the solution.
The prepared solution is poured into special molds preheated to 40 degrees. Filling is carried out to approximately ½ volume of the mold capacity.
After the solution is poured into the mold, it is sent to the maturation chamber, where final pore formation occurs, as a result of which the mass almost doubles in volume and gains transport strength. To activate the reaction in the solution and better distribute the composition, the molds are subjected to vibration loads.
After the solution has reached pre-hardening, the resulting irregularities are cut off from the surface of the frozen mass using stretched wire strings.
After pouring, the finished array is sent from the maturation chamber to the cutting line.
The next stage of work is to send the hardened products into an autoclave.

Aerated concrete is often denoted by the abbreviation AGB, that is, autoclaved aerated concrete, since its production is carried out using this equipment. And the autoclave itself, figuratively speaking, is a kind of large “pressure cooker” in which a pressure of 12 atmospheres and a temperature of 185 are injected and then maintained ÷190 degrees. Aerated concrete blanks are kept in such an atmosphere for 12 hours.

Prices for aerated concrete

aerated concrete

After ripening in an autoclave, the blocks are additionally separated, since during their processing they can join in some places.
Further, finished goods packaged in heat-shrinkable material or polyethylene - this is necessary to maintain a certain humidity in the structure of aerated concrete before construction begins.

The finished material can be stored until it arrives at construction sites for two - three years.

Here it is necessary to clarify that aerated concrete is not produced using an autoclave method. In this manufacturing option, the solution hardens under natural conditions, so high-tech modern equipment is not required for the manufacture of blocks.

However, such a material will not have the characteristics that manufacturers of autoclaved aerated concrete claim. The shrinkage of the material during the operation of the built house will be 3÷5 mm/m, while the blocks that have undergone treatment required temperature and pressure are only 0.3÷0.5 mm/m. If we compare the strength, then this parameter for autoclave blocks is 28÷40 kgf / m² versus products manufactured using a non-autoclave method, which have a value of 10÷12 kgf / m².

So, when choosing aerated concrete blocks, it is never a bad idea to clarify by what technology it was produced.

Production of foam concrete

The production of foam concrete blocks uses a simpler technology. However, to obtain a product with high performance, it is necessary to use high-quality materials.

Foam concrete, like aerated concrete, has a homogeneous porous structural structure, which is formed by artificially creating air bubbles in the mixture. This effect is achieved through the use of special substances included in the foam concentrate.

There are two ways to make foam blocks - cassette and sawing. The cassette method involves pouring the finished solution into separate molds. And sawing technology, therefore, consists in the processes of filling one large container with a mixture, and after it hardens, cutting this resulting mass into separate blocks of the required sizes.

So, for the production of foam concrete, cement grades M 400÷M500, sand purified from clay impurities, a certified foaming agent, calcium chloride and water. The foaming agent mainly determines the quality of the foam, so a carefully dosed, proven composition is used to make blocks. Poor-quality foaming can not only slow down, but even completely stop the hardening process of the finished solution. In addition, the composition of the foaming agent must meet the requirements of sanitary and hygienic standards, that is, it cannot contain toxic components.

The production process of producing blocks using the cassette method includes the following steps.

The first step is to mix cement-sand mortar. Its preparation is not particularly different from mixing ordinary concrete.
Next, in concrete mortar A foaming agent is added, after which the entire composition is mixed well until smooth. It is important to achieve the required air entrainment for high-quality foam formation.

The next step is to pour the foamed concrete solution into the molds under pressure.
Hardening of foam concrete occurs under natural conditions, but the duration of this process, unlike conventional concrete, is twice as long. It will take even several months for foam concrete to gain its final strength. If hardening takes place at temperatures below +10 degrees, the process will take much longer. On the production line, blocks can only be removed from the molds after two to three days. To speed up the hardening process, calcium chloride is added to the solution in a volume of 1÷2% of the amount of cement involved in the mixture.

The second version of foam concrete blocks, just like aerated concrete ones, is produced by cutting or sawing. Cutting of finished foam concrete according to linear dimensions is carried out using special equipment.

Prices for foam blocks

foam block

This version of the foam block manufacturing technology has a number of advantages, which include the following:

The edges and corners of the blocks have a clear geometry, without chips or flaws, which reduces the labor costs for their “commodity” processing.
The ideal geometry simplifies masonry work when building walls.
There is no lubricant on the surfaces of the blocks, which is used to lubricate each of the molds when concrete is poured into them. This approach significantly improves the adhesion of the material with the masonry mortar, as well as with the finishing material.
It is possible to cut blocks of different parameters, since the equipment can be configured to the required step.

It is these factors that contribute to the fact that many manufacturers are switching to this technology for the production of foam blocks.

So, let's emphasize fundamental difference in manufacturing aerated concrete and foam concrete:

- Aerated concrete – the porous structure is ensured by the active release of gas caused by a running chemical reaction. The resulting gas tends to escape to the surface, “pushing its way”, which determines the open, non-isolated nature of the cells. The increase to the specified volume occurs after filling out the forms.

- Foam concrete – the porous structure is ensured by the formation of foam with the entrainment of air (something similar happens when using soap or detergents). The bubble turns out to be isolated from its “neighbors”, that is, it is created closed cell air-filled structure. The solution immediately reaches the required volume, and after pouring into the molds it may sag somewhat rather than rise.

Characteristics of materials

In this section, we will try to compare the features of materials, determined by the specifics of their production, and talking about some of their advantages and disadvantages.

To begin with, let’s talk about the quality of the products themselves. Of course, you cannot sign for all manufacturers and all batches of material, but nevertheless...

The production of aerated concrete blocks in most cases is carried out in a factory environment, since this process requires special equipment. Therefore, production technology is monitored.

Foam concrete products can be produced both on high-tech equipment and in almost artisanal conditions. Naturally, very often there is a complete lack of proper control over how the solution is made, what material is used to mix the mixture, and the established by technology maturing time of foam concrete.

Density of materials. The structural density of foam concrete and aerated concrete is classified by grade of material. For both materials, this parameter varies from 300 to 1200 kg/m³.

It must be remembered that the higher the density of the material, the lower its thermal insulation qualities, and accordingly, the higher the thermal conductivity. The density of gas silicates classified as thermal insulation does not exceed grade 600. Next come thermal insulating structural and structural block products. Construction blocks high density manufactured for special purpose objects.

Strength for compression. The strength of foam blocks can vary and range from 0.75÷12.5 kg/cm², while for aerated concrete this figure is in the range of 1.5–3.5 kg/cm². the specific value depends on the brand of density.

Aerated concrete has the same strength throughout the entire block. And foam blocks may also have a non-uniform internal structure - due to the uneven distribution of the foaming agent when mixing the solution. Both materials have low flexural strength. Therefore, if they are chosen to build a house, special requirements are placed on the reliability and stability of the foundation - it is necessary to prevent uneven shrinkage of the structure.

Prices for gas silicate blocks

gas silicate blocks

Maturation (strength gain). Aerated concrete. due to features chemical composition and autoclave processing, reaches maximum strength already in the first stages of production. But as the walls are stored and used, it becomes lower.

Foam concrete gains the necessary strength after 28 days from the date of manufacture - this factor is very important to begin with construction work. To be sure that the material has good strength, it is recommended to purchase blocks in advance, a month before the start of construction, and store them on site. Walls built from fresh foam concrete has not gained strength, after construction they will shrink significantly and may crack. If it has already gained the required strength, then it will increase during its operation - the older the walls made of this material, the stronger it is.

Block sizes

It is impossible to say unambiguously about the sizes of both some and other blocks, since each manufacturer can produce them in different linear parameters. Although there are certain standards. For laying external walls, blocks of 200×300×600 mm are most often used, and for internal partitions - products measuring 100×300×600 mm.

By the way, the range is not limited to thicknesses of 200 and 100 mm. The table below shows other sizes of standard blocks.

Linear parameters of blocks, mm	Number of blocks per 1 m³, pcs.	Number of products on a pallet, pcs
100×300×600	55	80
120×300×600	46	64
150×300×600	37	48
200×300×600	27	40
250×300×600	22	32

The weight of products made from foam concrete and aerated concrete is almost the same, and the weight differences of the blocks depend on the type of material. The table below shows the weight of standard wall and partition blocks for reference:

Block sizes, mm	D300	D400	D500	D600	D700	D800	D900	D1000	D1100	D1200
200×300×600	11.7	15.6	19.4	23.3	27.2	31.7	35.6	39.6	43.6	47.5
100×300×600	5.8	7.8	9.7	11.7	13.6	15.8	17.8	19.8	21.8	23.8

To know the exact dimensions of the material, they must be requested from the manufacturer who it is planned to purchase building materials. In addition to the sizes indicated in the table, other options can be manufactured. Accordingly, the weight of block products will depend on the linear dimensions.

Quality and accuracy of linear shapes. Materials made by cutting or sawing have more accurate dimensions - this applies to both foam blocks and gas blocks. This quality allows you to reduce the thickness of the masonry joint to a minimum, literally to 2-3 mm. Very useful quality, since masonry joints become cold bridges, since the solution has significantly more high coefficient thermal conductivity.

Moisture absorption . Due to the fact that aerated concrete has a structural structure with open pores, it is a hygroscopic material, that is, it absorbs moisture well. Unlike aerated concrete, foam concrete absorbs moisture 8–9 times less.

So, if you immerse two materials in water for some time, aerated concrete will absorb moisture by 45–47% of the total volume of the block, while foam concrete will be moistened by no more than 5%. This method can be used to determine exactly what material the seller is offering, since at first sight sometimes it is impossible to determine whether it is aerated concrete or foam concrete.

Aerated concrete will become much heavier, foam concrete will practically not change its mass. Naturally, it will be difficult to check the material in a retail environment, so to check the seller’s honesty, you should buy one block, place it in water at home, leave it for a day, and then split it. If it is aerated concrete, then it will be saturated with water halfway into the depth of the block. Foam concrete will get wet no more than 15÷20 mm.

If the weather changes sharply, for example, if after long autumn rains, which saturate the aerated concrete with moisture, the temperature drops sharply, the moisture in the structure of the material will turn into ice. As a result, the unprotected structure may become covered with small cracks. And such damage is quite capable of becoming the “beginning of the end,” that is, erosion and destruction of the wall.

Therefore, it is necessary to cover it with a plaster layer immediately after the masonry mortar has hardened. This finish should protect the wall surfaces from moisture penetration.

Porosity of materials. Active moisture absorption aerated concrete is explained by the fact that the pores of the material remain open. Often its cut surface resembles a sponge. Closed pores form in foam concrete, which makes the material hydrophobic, and if it is immersed in a container of water, it will act like a float. long time stay on the surface.

Thermal conductivity. Even with the same brand of block products, they have different thermal conductivities. Thus, aerated concrete is a more effective thermal insulator than foam concrete. For example, for a house that is planned to be built in middle lane In Russia, the thickness of walls (if you do not use other thermal insulation layers) built from D 500 blocks of aerated concrete will be sufficient - 450 mm, but made of foam concrete it should have a thickness of at least 600 mm.
Vapor permeability. A high level is characteristic of both types of gas silicate, but still it is not the same. Vapor permeability promotes good air exchange in the premises of the house, as a result of which no air is created on the internal surfaces of the walls. favorable environment for the appearance of fungal or mold colonies.

Aerated concrete has higher permeability. When building a house from foam concrete blocks, it is necessary to provide an effective ventilation system, since the vapor permeability of this material is somewhat lower.

In this comparative table Absolute different parameters of aerated concrete and foam concrete are presented. Based on them, you can determine which of these materials is more suitable for building a house:

Name of parameters	Aerated concrete	Foam concrete
Foaming components	Fine aluminum and lime.	Wood saponified resin is classified as a moderately hazardous substance.
Manufacturing methods	Block slicing	Cassette and rifled
Place of manufacture	Factory production only	Factory or artisanal production
Structural structure	Homogeneously porous with open pores of equal size.	Heterogeneously porous with closed pores, with a range of their sizes.
Material density, kg/m³	200÷1200	200÷1200
Compressive strength, for grade D400, MPa	2	1.2
Curing time from the moment of manufacture	Immediately upon drying	No less than 28 days after manufacture, followed by constant strength gain.
Frost resistance, cycles	25	35
Thermal conductivity coefficient W/(m K)	0.1÷0.19	0.2÷0.36
Moisture absorption, % per day of constant contact with water.	Up to 47%	0.05
Linear dimensional accuracy	Minimum errors	When sawing an entire solid poured block, there are minimal errors; when manufacturing using the cassette method, significant flaws in the “geometry” are possible.
Shrinkage of masonry, mm/m²	0.5	2÷3
Vapor permeability, mg/m×h×Pa	0.16÷0.23	0.9÷0.11

Requirements for laying materials and surface finishing

In addition to the characteristics of each material, it is necessary to have information about the features of constructing walls and partitions from foam blocks and aerated concrete.

Requirements for the foundation of a building, being built Howfrom foam concrete and aerated concrete, are the same, since both materials are light in weight. However, the base for the walls must be strong enough, especially What hygroscopic aerated concrete, even covered with a plaster layer, with high humidity the air becomes almost twice as heavy, which increases the load on the foundation. Although foam concrete does not change its weight any significantly when wet, it, like aerated concrete, quite fragile material, so a reliable basis for it will also not be superfluous.

The horizontal surface must be covered with a waterproofing layer. This way you can protect the masonry material from the capillary entry of moisture into it from the side of the concrete base, which is in direct contact with the moist soil. As waterproofing, the well-known roofing material is most often used, laid on applied bitumen mastic onto the concrete surface.

Cutting, drilling holes, scoring cellular materials are produced in the same way - cutting can be done using conventional hand saw, and drilling holes using a drill and a core drill of the required diameter. Due to the fact that the material is porous, the cutting process is quite easy.
Speed of building construction. Both materials are light in weight, and their linear parameters are significantly greater than the dimensions of the brick. In addition, the surfaces of the blocks have sufficiently high adhesion, so the walls can be raised quickly. Especially in cases where the work will be carried out with the assistance of assistants.

Mortar for laying blocks. For laying foam concrete, ordinary concrete mortar or special masonry adhesive can be used. Aerated concrete is placed on an adhesive mixture specially designed for this material - this will help to significantly reduce the consumption of the solution, since a seam of 3 ÷ 4 mm will be enough to hold the blocks together.
Conservation of the construction site. If necessary, stop work on building a house on winter period, the object is being preserved. Moreover, walls made of foam concrete will last this period without compromising their strength, while aerated concrete must be covered with a waterproof film so that the material does not even absorb atmospheric moisture from the environment. Here it is necessary to clarify that aerated concrete during conservation of a construction site requires protection from moisture at any time of the year. But the greatest damage can be caused to the material by autumn rains, a sharp drop in temperature, and spring melting snow.

Prices for ceramic blocks

ceramic block

Retention of fasteners. Both materials require a special approach in this matter. However, d For porous building materials, today in specialized stores you can find a wide range of special screws, hardware, “ chemical anchors"and other mounting options.
Finishing materials for porous surfaces. For finishing facades built from gas and foam blocks are used plaster solutions, lining, siding, etc. In this matter, with the correct layout of the “facade pie”, there are no restrictions.

Insulation materials. Due to the porous structure of these materials, they themselves are very good heat insulators. Therefore, in many cases, additional insulation of the walls of the house is not even required. However, if such a need does arise, for example, a house is being built in a region with cold winters, then insulation is used for thermal insulation. And for external insulation It is best to use basalt mineral wool, which has excellent vapor permeability.

Plaster mixtures. Not all materials are suitable here. For finishing porous materials, special plaster mixtures are used, which maintain their high level of breathability. Such mixtures have good adhesion to aerated concrete surfaces, but before applying them on foam concrete on the surface of the wall is fixed with a reinforcing mesh, ensuring higher adhesion of the solution with smooth surface blocks.

What and how are walls made of gas silicate blocks plastered?

This work requires special care How plan preparation of surfaces, as well as in the choice of plaster and compliance with the technology of its application. Details can be found by following the link to the article on our portal.

Cost of gas silicate building materials

An important issue is the price of building materials. It is understandable - any future owner of a house, when building it, tries to find the most acceptable option, that is, the optimal price-quality ratio.

Therefore, you need to know that aerated concrete will cost, on average, 20% more than foam concrete. The latter is a more affordable material, since its production is not so complex and energy-consuming, and does not require high-tech equipment. However, due to the possibility of producing foam concrete even in “garage” conditions, if all the necessary components are available, very a large number of artisanal materials. Accordingly, such products do not have all the qualities of blocks manufactured in compliance with the technology in the factory.

When calculating the cost of materials for building a house, you must immediately take into account not only the price of the blocks themselves, but also the cost of the components of the solution or ready mixture, the consumption of which will directly depend on the quality of the block products. In addition, when using, you may need a steel mesh to reinforce the wall surfaces, and for aerated concrete - waterproofing materials so that you can create protection from bad weather at any time. Only by calculating everything needed for construction can you accurately determine which materials will cost less.

Now, knowing the qualities of both materials and taking into account the peculiarities of the local climate, you can choose the option that is more suitable for specific operating conditions.

And determine required amount gas silicate blocks, perhaps the calculator below will help many.

Both materials are artificial stone and belongs to the group “cellular concrete”. It is these that individual developers most often pay attention to, since this type of construction is considered the simplest and most cost-effective. Unfortunately, most articles devoted to the choice between aerated concrete and foam concrete for construction consider in detail only the characteristics of these materials, which implies “...draw your own conclusions.”

This is partly fair. But in this article we will analyze some properties, based on the advisability of using certain products in each specific case. It's clear that GENERAL recommendations will not be able to provide answers to all questions. So we will try to minimize such “gaps”, and also at the same time dispel some of the myths that are crammed into annoying advertisements.

By the way, in many articles devoted to the advantages and disadvantages of aerated concrete and foam concrete, there are paragraphs that say that these materials “do not rot,” “do not burn,” are not “corrosionable, rodent-proof,” and the like. We will deliberately skip the analysis of such “properties”, since it is simply not clear what audience such “valuable” information is intended for, when it is clear and, by definition, the materials are stone, albeit artificial.

First of all, what should you consider?

Local conditions. This is not only the climate, but also the location of the house (in a lowland or on a hill; closed by other structures, a forest belt or “blown” from all sides) and so on.
Your financial capabilities. Focusing only on the price of blocks means making a mistake. After all, a significant share of the costs is the arrangement engineering communications, finishing of the building and a number of other activities, without which the construction of houses from any type of product is impossible. From what, we have already written.

This leads to a completely logical conclusion that asking the question “which is better” is not entirely correct. Both materials have their own advantages and certain “cons”. Therefore, we will dwell on some of the features of construction, taking into account those problems that most concern the private developer.

Possibility of self-installation

Working with both materials is not particularly difficult. This is not the construction of a log house from wood, when you really cannot do without the help of a professional, at least as a work manager. Cellular concrete can be processed well and does not require special devices. Any owner can find a suitable tool. The relatively light weight of the blocks allows them to be moved manually, including to heights.

But there is one peculiarity. The process of “adjusting” aerated concrete (AC) products is somewhat more complicated. The fact is that the fastening of these blocks is carried out using an adhesive composition, while for the installation of foam concrete (FC) blocks a mortar is used. Therefore, the accuracy of product processing is important, otherwise it will increase sharply, and it is not cheap. And the formation of so-called “cold bridges” cannot be avoided.

Therefore, organizations selling GB blocks offer to immediately purchase the appropriate device for leveling the edges, which must be done after cutting the products (although you can make it yourself). But the process itself requires some skills and takes some time.

There is one more difference. It will not be possible to set up the production of GB at home (if we talk about quality), but any developer is quite capable of producing PB at the work site. Forms can be used either purchased or self-assembled from scrap materials.

There is an established opinion that since aerated concrete products are factory-made, their geometry is more correct, which allows for smoother masonry. But for some reason, no mention is made of the fact that since the foam concrete blocks are “set” on the mortar, it will not be difficult to correct or level them on such a layer even for an inexperienced craftsman.

Construction Features

We are talking about number of floors. In this regard, aerated concrete is “more reliable”, and from these blocks you can safely build 2-3 floors. But the same cannot be said about foam concrete - a number of additional measures will have to be carried out (for example, reinforcement). Therefore - plus the “nth” amount to the total expenses.

And one more moment. The foam concrete mass can be poured into formwork, that is, it can be equipped monolithic structures. For example, additional insulation, interior walls complex configuration - there are enough options. This adds an extra “plus” to foam concrete.

Exterior finishing

There is an opinion that it is not necessary to veneer it, but it is necessary to use foam blocks, since they do not have a very “attractive” appearance. It’s like looking at it - on the one hand, the aerated concrete structure looks neat, and the color is noble - white, especially since everyone has their own concept of beauty.

But there is one, and very significant, nuance. Unlike its “brother”, GB absorbs liquids well. So it turns out that, taking this factor into account, it will be necessary to “protect” the walls from precipitation. Otherwise, constant dampness in the house and destruction of the material cannot be avoided. Therefore, all advertising “propaganda” claiming that you can save a lot on finishing aerated concrete (compared to PB) is nothing more than a fiction, another “temptation” based on the incompetence of the buyer. Even if we limit ourselves only to injection (or impregnation) waterproofing, it will also require certain material investments.

Construction of the building

Naturally, since we are talking about a residential building, we will have to carry out a whole range of measures both during the construction process and during occupancy. This includes laying pipes, cables, and placing appliances (for example, a boiler), pieces of furniture on the walls, and so on. But how to attach it?

The GB holds the dowel securely, but as for the PB, there is no way to do without anchors - the material is too porous. This is precisely the big (albeit relative with a skillful approach) “minus” of foam concrete. Therefore, the choice of type of finishing for PB products is somewhat limited. For them, most often the owner chooses plaster compositions to simplify (and reduce the cost) the process external design surfaces.

Which house is warmer?

In both. The main thing is to choose the right “parameters” of materials. These are dimensions (meaning the thickness of the walls) and density. Much depends on the correct installation and thermal insulation measures. But one thing is certain - in such houses it is more comfortable than in brick ones, since both foam and gas blocks are able to maintain the microclimate at the same level both in summer and in winter.

Which construction is cheaper?

In practice, the costs are approximately the same (with all the same “parameters” - dimensions and the like). If you compare product prices, PB is cheaper. Its 1 m3 will cost approximately 2.5 – 2.9 thousand rubles, while for a GB the cost of a “cube” is in the range of 3.1 – 3.7 thousand (all other factors being equal).

But construction costs are determined not only by this. Glue (when constructing walls from GB) is laid thin layer, but the solution (for PB) is thicker. If we take into account the price of cement, then the total costs are approximately the same.

Environmental friendliness

This problem worries many; it has even become fashionable to think not only about one’s own health, but also about the environment. In this regard, many give foam blocks a “minus”, since their production technology is based on the use of “chemistry”. But for some reason, the fact is forgotten that more “ecologically friendly” GB products are installed using adhesives, which also contain various chemicals. Therefore, in reality, there is simply no point in talking about the absolute “purity” of construction.

Lifetime

It is believed that for blocks from GB it is 1.8 times greater than for PB. But these data are relative. Much depends on the quality of installation and finishing work, as well as on the regularity and correctness of preventive measures, since good care significantly increases the durability of any material.

For the thrifty owner, the information is more than complete. And which “stone” to choose – think for yourself, taking into account the stated considerations about the nuances of construction from these “light” concretes.

Construction of a residential building is a special process that does not tolerate errors, especially in terms of durability and comfort. Especially in our latitudes, where temperature regime may fluctuate within significant limits, as well as weather. Choice quality material in this case, it is an important mission, and one who knows what he is looking for can cope with it. Today we look at two widely used modern housing construction materials - aerated concrete and foam concrete, compare them and evaluate each material according to several characteristics.

Comparison of materials

Foam concrete is essentially cement, sand and a foaming agent. All this is mixed, poured into molds and left alone until completely hardened. That is, the process can be carried out directly on the construction site.

Foam block and gas block - appearance

But aerated concrete requires high temperatures and a humid environment. It consists of lime, cement, water and sand. Aluminum powder in this composition acts as a gas former. The resulting mixture is cut into blocks with strings and placed in an autoclave. There, under the influence of high pressure, the material acquires its final form and its best qualities - resistance to mechanical stress, durability, fire resistance and flexibility in processing.

It turns out that both materials are lightweight concrete, only the way to create air bubbles in them is different.

Both materials are manufactured according to the same GOST, which means they meet the same requirements. Their physical and technical characteristics almost repeat each other. But this does not mean complete identity of aerated concrete and foam concrete.

Aerated concrete with its heat treatment has some advantages, but there is no point in saying that it is superior to foam concrete. Nevertheless, it is the quality of cement and its density that determine the degree of quality and reliability of the product. The laying of these two materials is also different: aerated concrete blocks are placed on glue, and foam concrete blocks are placed on ordinary cement mortar. It is cheaper than glue, but practice shows that much more of it is required, and it is more difficult to work with.

It turns out to be a curious thing - aerated concrete with glue is more expensive than foam concrete with cement mortar, but at the same time the cost is almost the same. In addition, the glue does not allow cold bridges to form, which means warming interior spaces It will be easier, which will have a positive impact on cost savings.

Another difference between the materials is the degree of accuracy of the block sizes. However, at the factory the dimensions are observed much more accurately than at the construction site. Therefore, laying aerated concrete is easier and more pleasant.

Comparative table of characteristics of foam concrete and aerated concrete

Advantages and disadvantages

If we talk about the production of materials, then foam concrete from the point of view of the complexity of the process looks preferable. For aerated concrete, you need to build a workshop, install a powerful electrical network, and a gas pipeline. Foam blocks can be easily produced using portable equipment, which is not difficult to find - there are plenty of modifications of them on sale. Another thing is that a simplified production method often attracts illiterate manufacturers who do not strive for accuracy of linear dimensions, compliance with the level of thermal conductivity, density and strength. You can avoid encountering low-quality products by finding a competent manufacturer who has all the necessary quality certificates and periodically tests its products for compliance with modern standards.

Foam concrete and aerated concrete blocks are easy to lay, and due to their size, they save glue or cement mortar

Foam concrete can be toxic - since it is not autoclaved, chemical processes are used to create it. This also affects the strength of the product. With the same density, the degree of strength of aerated concrete and foam concrete is different. Let's take, for example, a density of 500 units. With this indicator, aerated concrete copes well with loads, while foam concrete cannot boast of high strength and is used only as insulation.

Water absorption and frost resistance - two important indicators for the material.

An aerated block can absorb more water than a foam block, but is less resistant to low temperatures. True, during the construction of residential buildings they outer side covered protective layer in the form of plaster, tiles, siding and other materials, which means that the gas block will be protected from exposure to water.

Video: characteristics of gas and foam blocks

Home construction

Houses built from these materials will cost less than brick ones. And there are reasons for this. Firstly, aerated concrete and foam concrete are lightweight materials, which does not oblige the builder to build a massive foundation. Its light version is enough. Secondly, the heat and sound insulation of both materials is at the same level, which allows you to subsequently save money. And not only in the future. During the construction process, walls of smaller thickness can be erected, which means saving money on materials. Thirdly, savings in materials also apply to glue and cement, of which not so much will be required for large volumes of blocks.

Houses made of foam blocks and gas blocks are very reliable, because these materials are durable and non-flammable. They do not rot and are not susceptible to attacks by rodents and pests.

If you are laying internal structures, such walls will be easy to tap. And finally, the most important thing is that these walls “breathe”, which creates comfortable living conditions in the house.

In the construction of buildings, blocks from different materials. Aerated concrete or foam concrete: which is better to use? Both materials are cellular concrete. This is a composition that consists of many cells. But gas blocks and foam blocks are made in different ways.

Block characteristics

To understand the difference between foam blocks and gas blocks, you need to read their characteristics. What is the difference between foam concrete and aerated concrete? Aerated concrete is a simple material, but its creation requires high-tech equipment. During processing, it can go through an autoclave, in which the material is sintered at high temperatures. It can also be performed using a non-autoclave method. The first one will be much stronger. The same components are used for manufacturing:

Portland cement;
water;
lime;
sand;
aluminum powder.

By combining substances, you can change the characteristics of foam concrete and aerated concrete blocks. Products made from foam concrete or aerated concrete are made in approximately the same way. The foamed mass, which has acquired initial strength, is cut into blocks and dried on outdoors or in a special device. What is better: gas block or foam block? In Europe they use aerated concrete. In Great Britain it is used in the amount of 40% of the total mass of building materials, in Germany this percentage reaches 70. But all this is used only in low-rise construction.

What is the difference between a foam block and a gas block? One is created using chemical reactions, the other using special foam. These materials can be made in a special installation or using a regular concrete mixer. The solution is laid out in forms from which they are removed ready-made blocks. The forms themselves can be:

plywood;
metal.

Plywood ones are cheap products, but they have disadvantages. They quickly get wet and fail after a month or two of use. Therefore, they are not suitable for producing blocks on an industrial scale. For metal molds 4 mm thick metal is used, which is cut by laser. And such products have disadvantages. The side fastenings are very difficult to tighten, so the metal bends and the finished blocks can be humpbacked. Blocks can be poured into molds both in production and at home. And the method of pouring a slab is used mainly only in production.

Poured mass in the form large slab cut into pieces by saws the right size. The equipment is expensive; dust and crumbs remain during operation. It can be 0.5% of the total mass of the solution consumed. The difference between a gas block and a foam block is almost invisible at first glance. Both materials are very similar in appearance. But some advantages can be found in each of them. Aerated concrete blocks are easy to process and easy to process. This material is very easy to process: it can be cut and drilled even with hand tools. The blocks are used to build walls for bathhouses and houses. It is easy to make grooves in the walls of a house made of aerated concrete to place water and sewer pipes, laying electrical wiring.

Advantages of materials

Foam concrete walls for a bathhouse or house have approximately the same performance as aerated concrete. Their differences are difficult to notice. Foam concrete blocks, like aerated concrete blocks, are lighter than brick, retain heat well, and are frost-resistant and fire-resistant. Both of these materials can withstand temperatures of about 300°C and do not age or rot. They have good sound insulation; walls up to 20 m high can be built from aerated concrete and foam concrete. Does it make sense to compare these blocks if the difference between an aerated concrete block and a foam block is almost invisible? But it is better to give preference to aerated concrete for the reason that load-bearing walls it is much stronger.

Foam concrete has some advantages:

it is significantly superior in quality to wood and brick;
The block is lightweight, which allows you to avoid using lifting mechanisms during construction with foam concrete;
the blocks have the same dimensions;
the masonry is carried out using glue, which is warmer than mortar;
walls made of foam blocks do not burn;
foam blocks can be made directly on the construction site;
the material exhibits greater resistance to frost;
has a high degree of sound insulation;
a foam block does not require a frame or a strong foundation.

Among the disadvantages, it is necessary to mention the shrinkage of the walls, which occurs within a month. Surface finishing cannot be done before this date.

Walls lined with aerated concrete have their disadvantages. The main one is the fragility of the material. Throwing or hitting aerated concrete blocks is not recommended. It can only be transported on Euro pallets. Aerated concrete differs from foam concrete in that it is able to absorb moisture from the air. For this reason, it is not recommended to store aerated concrete blocks without a roof. When absorbing moisture, blocks increase in weight and lose their strength. With further freezing, the material may collapse.

When laying, the gas block is able to absorb a lot of moisture from the solution. This makes the process of building walls more difficult.

Which material to choose?

If we combine all the characteristics, we can conclude that foam concrete can be produced on a construction site, while aerated concrete can only be produced under production conditions. In terms of fire resistance, products made from aerated concrete and foam concrete are in no way inferior to each other. A comparison of foam concrete blocks with aerated concrete in terms of shrinkage will be far from being in favor of foam concrete, which is significantly inferior in this regard to walls made of aerated concrete blocks. Foam concrete products are cheaper and more accessible than aerated concrete. But you can also buy very low-quality material. What is the difference between aerated concrete? A house made of aerated concrete is much stronger. It can be used to build not only a bathhouse, but also a multi-storey building.

If you consider and compare the advantages of foam block and aerated concrete, you can find pros and cons in each building material. What is the best way to build a bathhouse, what is the difference and what is the difference between foam concrete and aerated concrete? It is better to use aerated concrete for building a house or bathhouse. It is more expensive, but much stronger than its foamed counterpart. How to distinguish a foam block from a gas block? After all, they are made from the same components, but using different technologies. Only in the production of foam concrete is used SDO (saponified wood resin), and in the production of aerated concrete - aluminum in the form of fine dust. When manufacturing materials, you can get different sizes that differ significantly from standard ones.

The main characteristics of gas blocks and foam blocks are very similar. This similarity makes the materials identical at first glance. Only accompanying documents and factory packaging will indicate the brand of material. But the difference between a foam block and a gas block can be seen upon careful observation. Upon careful examination of the compared products, you can see that the air pores on the surface of the aerated concrete block are open. The material is like a sponge. Water gets into these pores, and the weight of the material increases significantly. During the day, weight gain occurs up to 47%. Foam concrete can float in water for a month without becoming saturated with moisture.

Cutting aerated concrete blocks gives more accurate dimensions of the material. This is its peculiarity. It is better to build a house or other structure from such material. To glue blocks, you need a significantly smaller amount of glue, since its layer usually does not exceed 2-3 mm. What is the difference between foam block and gas block in terms of heat retention? It's quite noticeable. If you compare the two materials, their characteristics in this case are completely different. The difference between a foam block and a gas block is that the second material is a better heat insulator. The characteristics of a 450 mm thick wall made of aerated concrete are the same as those of a 600 mm thick wall made of foam concrete.

Conclusion on the topic

What to choose for building a house or bathhouse: wood and brick, gas block and foam block? What are the advantages of these materials, their pros and cons? What is stronger: walls made of aerated block or foam block? Which blocks should I buy? All these questions concern new developers. Foam concrete is an excellent material related to cellular concrete. It is relatively cheap. Gone are the days when houses were built only from brick and wood. Nowadays, buildings made of foam block structures are becoming more and more common. Aerated concrete structures can be built even better. If you use a foam block, it does not get wet. This ability is one of its best qualities, although the use of gas blocks and foam blocks does not make much difference.

These materials can be easily processed with hand tools. They can be sawed, drilled, tapped. They are lightweight. Aerated concrete and foam concrete: which is better? Foam concrete can shrink quite significantly, which is not typical for aerated concrete. Block surfaces can be covered with clapboard, siding, plaster, or paint. Such walls do not need thermal insulation. Walls have their own disadvantages and advantages, similarities and differences. What material to choose for personal use is up to the owner. Very reliable, but expensive material is aerated concrete. You just need to protect it from water penetration. The good quality and evenness of the blocks made it popular among developers. It is easy to install, reliable and beautiful.

Using foam concrete or aerated concrete: which is better for construction? These materials, consisting of the same components, may differ from each other. But this is quite difficult to determine. Which is better: foam blocks or gas blocks - should now be clear.

The lack of natural gas in many suburbs and cottage villages has a particularly acute effect during the heating season, when you have to pay literally exorbitant prices for every kilowatt of thermal energy. But possession own home has its advantages too. One of them is that a low-rise building can be made as warm as desired by using structural and thermal insulation materials – cellular concrete blocks – when constructing walls. They are made from foam concrete and aerated concrete, but let’s try to figure out what is the difference between them and which is better.

Blocks made of aerated concrete and foam concrete

Classification

These two types of lightweight concrete only have the same classification. The difference between foam concrete and aerated concrete lies in the density and type of materials, although in regulatory documents The thermal conductivity of foam concrete and aerated concrete at the same density is considered equal.

Thus, the lightest foam concrete blocks with a density of up to 500 kg/m³ are classified as thermal insulation. And for aerated concrete, blocks with a density of up to 400 kg/m³ are considered thermal insulating.

Aerated concrete blocks with a density of 500-900 kg/m³ are considered structural and thermal insulation and serve as building materials for self-supporting walls without reinforcement. And when laying armored belts in every fourth row, they can be used to build load-bearing walls of low-rise buildings. For foam concrete, these include blocks with a density of 600-1000 kg/m³.

Foam concrete and aerated concrete blocks with a density above 1000/1100 kg/m³ are classified as structural.

For reference! Due to the optimal strength/thermal insulation ratio, the most popular blocks are D500 and D600 (the number indicates density).

Visual difference between blocks of different densities, using aerated concrete as an example

But density and thermal conductivity are the only indicators that closely coincide for these two similar, but still different materials. And the differences between them lie at the level of composition and production technology. Therefore, to choose aerated concrete or foam concrete, which is better, you need to carefully study all the properties of both materials and the conditions of their use.

Video description

Today we will discuss how to build an inexpensive house from aerated concrete. How much does a turnkey aerated concrete house cost in the following video:

Production technology

If we consider the structure of both types of cellular concrete, we can see that even here there are differences between them. With the same density, foam concrete visually has a greater spread of cell sizes from the smallest to the largest, and aerated concrete is more uniform. This difference in structure is determined by the way the cells are formed, but this is not the only difference between aerated concrete and foam concrete.

Foam concrete production

The composition of foam concrete is classic concrete with Portland cement binder and sand filler. Moreover, filler is added only for medium and high density foam concrete, starting with grade D500. The cellular structure is obtained by mixing the prepared concrete mixture with a foaming agent or ready-made foam. This is what distinguishes the two main manufacturing methods: classical and barotechnology.

Kit for the production of foam concrete using barotechnology

Pressure technology involves adding a foaming agent directly to the mixture without using a foam generator. Usually these are mobile installations that allow you to produce foam concrete directly on site. Their productivity is low, but quite sufficient to provide building materials for the construction of a low-rise building. The disadvantage of the technology is the increased consumption of foaming agent and slightly lower strength of foam concrete compared to classical technology.

The classic technology is a little more complicated - the same prepared concrete mixture is used, but it is mixed with ready-made foam, which is obtained in a foam generator from a foam concentrate and water. The production process looks like this:

sand is poured into the concrete mixer first (to “bind” the remaining water from the previous portion);
add cement and water, mix until smooth;
a portion of foam is prepared separately in a foam generator (in accordance with the required density of foam concrete);
add foam to the concrete mixer and mix for 3-5 minutes;
liquid foam concrete is transported through a flexible hose into a mold or formwork.

Classic scheme for the production of foam concrete

On our website you can find contacts construction companies who offer house design services. You can communicate directly with representatives by visiting the “Low-Rise Country” exhibition of houses.

The general advantages of foam concrete production include:

simple production technology;
inexpensive equipment, including “mobile” equipment, which can be installed on site;
possibility of laying in formwork with monolithic construction walls;
variety of ways to make blocks.

Three types of equipment are used to make building blocks from foam concrete:

pouring into special molds, followed by stripping;
pouring into cassette molds;
pouring into a massive mold, followed by cutting into blocks.

Stripping, removal from cassettes and cutting occurs after the initial hardening of the mixture. When modifiers and fiber are added, this period is reduced to several hours. But the manufacturing process does not stop there - the foam blocks still have to “ripen”. It is untimely demoulding and incomplete ripening that can affect the final quality of foam concrete blocks. For example, insufficient exposure after manufacturing and before installation can lead to shrinkage of the blocks as part of the wall, and the use of waste to lubricate the molds can lead to peeling of the front part.

Stripping foam concrete blocks

Production of aerated concrete

In composition and technology, aerated concrete is closer to silicate brick, which is why building blocks made from it are often called “gas silicate”.

A lime-cement mixture is used as a binder, which consists of ¾ of quicklime, crushed to a powder.

The classic filler is quartz sand.

To obtain a cellular structure, a gas-forming agent is used – aluminum paste or powder, consisting of 90% “active” metal.

And, as with any concrete, to “mix” clean (drinking) water is added to the mixture.

The technological process for manufacturing aerated concrete blocks looks like this:

The sand is washed, water is added and ground to a sludge state so that the particle sizes are comparable to cement and ground lime binder.
Sand sludge is mixed with binder.
The gas-forming agent is diluted in water and added to the mixture of sand and binder.
Mix all the ingredients and pour into the mold.
After initial maturation is completed, the monolithic gas silicate is removed from the mold and cut into blocks.

Cutting aerated concrete blocks from a monolith

The blocks are placed in an autoclave, where, under the influence of saturated steam, the process of gas formation is completed, active aluminum is bound to the silicate mixture, and the cement stone is hydrophobized.

The output is fully “ripened” aerated concrete blocks, ready for packaging and transportation to the site.

For reference! The production of such blocks is possible only in conditions industrial production. In this case, it is almost impossible to “run into” handicraft products of low quality. This is the main difference between aerated concrete and foam concrete at the technology level.

Advantages/disadvantages of foam concrete and aerated concrete

The general advantages of these two types of cellular concrete look like this:

Availability and low cost of ingredients determines relatively low price building blocks. But with the same density, aerated concrete is 20-30% more expensive than foam concrete (in terms of 1 m³). This is due to high overhead costs - more expensive equipment and at great expense electricity for production. And when choosing, you should pay attention that many sellers get confused in the subtleties of defining technologies - quite often aerated concrete blocks are positioned as autoclaved foam concrete.

Autoclave hardening is an industrial technology, and foam concrete is most often produced in mini-enterprises

High thermal insulation properties. Each manufacturer indicates its own indicators, which may vary slightly. But foam concrete is more “stable” compared to aerated concrete and its thermal conductivity is not so dependent on the level of humidity in the surrounding air. This is explained by the closed cell structure, lower hygroscopicity and vapor permeability.
Both materials are lightweight cellular concrete, so the load on the foundation is low.
Both materials are non-flammable and environmentally friendly.

Having considered what properties foam concrete and aerated concrete have, what is the difference between them, can be interpreted in two ways - each feature has both a positive and a negative side.

The open cell structure of aerated concrete determines high breathability - this indicator is better than that of wood across the grain. But this same ability determines the hygroscopicity of gas silicate blocks - they easily absorb moisture, which leads to moisture in the structure and partial loss of load-bearing and thermal insulation qualities. Therefore, during breaks in construction, walls and partitions must be covered, and after construction is completed, the finishing of the facade must ensure the weathering of excess moisture.

Preserving a block house for the winter

In foam concrete, most cells have a closed shell. Only in blocks that are cut into solids, the top layer is characterized by an open structure. Therefore, the vapor permeability of foam concrete is almost as low as that of ordinary concrete. This means that the blocks do not have breathable properties, but their water absorption is low. And in this case external finishing is more decorative than protective.

In terms of compressive strength, aerated concrete blocks are slightly better than foam concrete blocks. So, with the same density D500, foam concrete from most manufacturers is classified as thermal insulation with strength class B1, and aerated concrete is classified as structural and thermal insulation with class B2.5.

The dimensional accuracy of building blocks is largely influenced by production culture. Gas silicate blocks, obtained by cutting from solid wood, have an absolute match in size and a perfectly flat surface. This allows them to be laid on an adhesive mixture with minimum thickness seam, which almost completely eliminates heat loss that occurs with conventional masonry techniques. Even better in this regard are walls made of tongue-and-groove aerated concrete blocks, which do not have “through” vertical joints.

Tongue-and-groove form of gas block

Foam concrete blocks produced by casting into molds do not have such precise geometry. And only blocks cut from solid wood are distinguished by their dimensional stability in one batch. In this matter, what better aerated concrete or foam concrete, the second loses significantly.

Video description

For a brief and visual comparison of gas blocks and foam blocks, watch the video:

Conclusion

It is definitely impossible to answer which is better - foam blocks or gas blocks for building a house. If foam blocks are made without violating production technology and have gone through the full “ripening” cycle, then they are no worse than aerated concrete, the only advantage of which is the absence of handicraft materials on the market. And some differences in gas permeability and water absorption have two sides - the lack of one property is compensated by the presence of the other. Therefore, choosing foam block or aerated concrete, which is better for the construction of your home, is based on an analysis of all related factors, starting from the properties land plot, to the climatic conditions in the region.