What is the difference between gas blocks and gas silicate blocks. Which is better: foam blocks or gas silicate blocks. Advantages and disadvantages of aerated concrete and gas silicate blocks

The choice of aerated concrete or gas silicate is still of concern to many novice builders. After all, these materials have been widely used relatively recently. Nevertheless, both of them are representatives of cellular concrete, and their main advantages, as well as disadvantages, are quite predictable. It remains only to understand the nuances that distinguish gas silicate from aerated concrete.

To begin with, it would be good to understand how related these two species are. After all, gas silicate is often called autoclaved aerated concrete, and confusion arises. But the difference becomes obvious, one has only to determine the composition and technology of obtaining materials.

In terms of composition, foamed concrete, which is used in both cases, has little difference. The only question is the binder. Aerated concrete blocks are made with the addition of lime (about 24%), while only cement is present in aerated concrete. This is where the differences end:

• in both cases, the filler is sand;
• large fractions such as crushed stone are not introduced - they are partially replaced by lighter blast-furnace slag;
• foam-forming components based on aluminates are introduced, providing a porous structure to gas blocks.

The next difference, which led to the separation of gas silicate and aerated concrete into two different groups, is the production technology, or rather, the process of mortar hardening:

1. Aerated concrete blocks are cut from non-autoclave foamed concrete, that is, normal hardening. Although it is better and more expedient to use aerated concrete for the installation of monolithic structures. The solution is poured into the formwork or mold and there, for the prescribed 28 days, the hydration process takes place.

2. Gas silicate blocks are also cut in parts, but from blanks of a limited, standard size. The setting of the solution poured into the molds takes place in special ovens (autoclaves) under certain conditions of temperature and pressure. As a result, the blanks have less shrinkage and an almost unchanged geometry.

The difference in the curing speed of autoclaved and non-autoclaved aerated concrete is simply huge, because gas silicate, under the influence of hot steam, gains the necessary strength after 12 hours. And even if the hardening of non-autoclaved concrete is accelerated by thermal and moisture treatment, this will not reduce the hardening time to those shown by its “opponent”.

The heating of the mixture in autoclaves occurs not only at an elevated temperature of about +180 .. +190 ° C, but also under a pressure of 12-14 atm, which is provided by the supply of superheated steam. As a result of such processing, aqueous calcium silicate (tobermorite) is formed in the massif - an artificially recreated analogue of a natural rare mineral. Thanks to him, gas silicate very well holds high loads, "unbearable" for blocks of ordinary aerated concrete, and acquires increased crack resistance. This significantly expands the possibilities for its application in construction.

Of course, autoclave technology has its drawbacks, and very significant ones:

• The energy intensity of production and, as a result, the rise in the cost of products. Moreover, it is quite inexpensive to make a mixture for home production of aerated concrete.
• The inability to produce products of any size, as their dimensions are limited by the size of the furnace. This difference with normal hardening technology is not very significant in the production of individual blocks. But it is precisely this that does not allow the use of more durable foamed concrete in some construction works.

Like this: a slight change in the raw material composition, the creation of other hardening conditions - and at the output we get two completely different materials with a huge difference in characteristics. However, aerated concrete can also be loaded into furnaces, but gas silicate of good quality cannot be obtained without the use of autoclaves.

Feature Comparison

Aerated concrete, in comparison with gas silicate, is less susceptible to moisture and, accordingly, frost. The reason for this is the closed pores of the surface. But this does not play a big role, since all cellular concretes need reliable protection from water. And after cutting the foamed monolith into blocks, these advantages will be vanishingly small at all. This can be seen by comparing the water absorption rates for both materials - the difference is not significant.

It is much more important in construction to take into account the differences in strength and thermal insulation characteristics. After all, in order to choose the right material, you need to find the optimal combination of reliability and comfort.

The construction of a house from aerated concrete requires careful calculations regarding the bearing capacity of the foundation and walls, as well as their resistance to heat transfer. And in rough finishing work, it is better to focus on the economic component and choose what is cheaper.

It is worth considering the technical characteristics of both materials well, as the difference between aerated silicate and aerated concrete becomes obvious. The first has a large range in density, which allows you to choose on the market not only a structural, but also a “warm” option. The greater number of pores in lightweight blocks makes them an excellent insulating material.

Due to the increased density, aerated concrete does not retain heat so well, but at the same time, the difference in strength is clearly not in its favor. And the reason is the change in the mineralogical composition of the gas silicate, which has already been mentioned.

Not the last role in such a large gap in characteristics is played by the degree of homogeneity of the resulting structure. Aerated concrete, if you look at the cut, has pores of different sizes, unevenly distributed in the body of the block. But the gas silicate, subject to the manufacturing technology, is better structured - it turns out to be more homogeneous with the same air cells with a diameter of 1-3 mm.

Despite such an abundance of differences, aerated concrete blocks have some similar properties to gas silicate ones. But only in terms of water absorption and breathability.

Summary: what to consider and what to remember

Studying the difference between foamed concrete and gas silicate, most come to the conclusion that it is better to choose the second option for building a house. That is why autoclaved concretes are more widely used in our country, and the price difference scares off a few. But in some cases, you can’t do without aerated concrete, so before you finally choose a building material, you need to weigh everything.

For each of them, it is better to determine the scope where all its advantages will be manifested.

Aerated concrete blocks and monolithic structures:

• Used where price matters, not quality. For the construction of small facilities that do not experience special loads, it makes no sense to buy expensive gas silicate. It is wiser and cheaper to choose aerated concrete.
• The non-autoclave method of production also opens up wider possibilities. Light and warm screed for the floor, monolithic internal partitions cannot be laid in the oven. Therefore, such structures are made only by the non-autoclave method.
• The monolithic method will also come in handy when building small foundations, which are always better done cheaper. The closed pores will be protected by a smooth concrete surface, while the silicate is a mineral sponge on the outside.

Gas silicate blocks should be used where their strength is required: in the construction of load-bearing walls and floor slabs, in structures that require additional reinforcement. It can only be supplied as individual prefabricated elements. But the dimensional accuracy and easily predictable volume make it possible to make them more complex, for example, with tongue-and-groove locks.

Aerated concrete, although much cheaper, is used much less frequently in the form of blocks. But it is indispensable in the manufacture and monolithic products of non-standard shapes or sizes.

When choosing the best option for a building material, the question arises of gas silicate or aerated concrete, which is better? Such porous concrete blocks are often used for the construction of building walls and ceilings. They have many common properties, due to which they compete with each other. For this reason, people are wondering when choosing aerated concrete or gas silicate, what is the difference? Their differences are due to the method of preparation.

Features of aerated concrete and gas silicate

It is worth considering in more detail the distinctive qualities of each of the materials:

• Aerated concrete is a composite material, which is made according to classical schemes, when its hardening process occurs in natural conditions. The products are characterized by the presence of a porous structure, when air sections having a spherical shape, as well as a diameter of 3 mm, are evenly located in them. The binder is Portland cement, the amount of which in the composition of aerated concrete blocks exceeds 50%. Based on its concentration, the color of the product and the main properties of the material are determined;
• Gas silicate products also have air cells. The main elements that are used to create them are quartz sand, as well as lime. Usually the ratio of components is 3:1. For the process of gas formation, aluminum powder is added to the composition, as well as water, in order to bring the solution to the desired consistency. Then the mixture is filled with a special form, which the finished building material should receive. Production is carried out according to autoclave technology, when products are subjected to heat treatment, placed in special chambers where high pressure is injected. At the end, the array is cut to the required dimensions of the silicate aerated concrete block.

Given that both types of building materials are porous concrete, each of them has its own characteristics, which determine how aerated concrete differs from gas silicate.

External difference

An unprepared person, seeing such building materials nearby for the first time, will not be able to give an exact answer, where is the gas silicate block, and where is the aerated concrete one. But they have their own visual differences, which are due to their composition and production technology. For example, Portland cement is not used in the manufacturing process of silicate products. But in the creation of aerated concrete, it is needed, as it is its binding element. This factor affects the color of products, which is the external difference between gas silicate blocks and aerated concrete:

• So, the first ones are created by the autoclave method and contain a large amount of lime, due to which they are white;
• In the second products, the acquisition of characteristics occurs under conditions of natural solidification using Portland cement, which gives them a gray tint.

By changing the amount of binder in the materials, there is a deviation of their color from other similar products. So, with an increase / decrease in the content of cement in aerated concrete, its color can vary, ranging from dark gray to light gray. But in silicate variants, the color scheme starts bright white and ends with a grayish-white color. In addition, the difference between similar building materials lies in the different level of hygroscopicity:

• Gas silicate at high humidity absorbs it faster, due to when there is a sharp temperature drop, this leads to a violation of the integrity of the blocks;
• Liquids are more difficult to get into aerated concrete products, due to the closed air pores. Due to this, such materials have good strength and moisture resistance.

Such blocks require finishing due to their porous outer surface. To create with their help comfortable conditions in the premises, it is required to carry out their correct external and internal decoration.

Benefits of gas silicate

This type of building block is popular. It is produced by using lime as the main binder and processed by the autoclave method. Its advantages are the following properties

• Strength. Thanks to the technology of creating blocks, they are uniformly distributed throughout the volume of air bubbles, which allows the gas silicate to have high strength characteristics. It is slightly prone to cracking and shrinkage.

In the presence of the same density indicators, gas silicate products have a 1.5 times higher level of strength than aerated concrete.

• Noise isolation. Due to the presence of an increased number of pores inside the materials, it has good soundproofing properties;
• Specific gravity. Due to the smaller mass of such blocks, for their use there are less requirements for the bearing capacity of the foundation. This allows you to reduce the cost of construction when using them;
• Block shape. Due to the fact that after autoclaving the material is cut to obtain the desired dimensions, the permissible deviations do not exceed 3 mm;
• Aesthetics. Buildings built from white gas silicate have a more attractive appearance.

Advantages of aerated concrete

Even taking into account the lower strength indicators and thermal insulation parameters, there are differences between aerated concrete and gas silicate, which speak in favor of the first material:

• Moisture absorption. Such products have a low level of moisture absorption, which is due to the smaller pore volume in the structure of the products. But when using them, it is required to create a special protective coating;
• Price. The most significant factor influencing the choice of material is its cost. In this regard, aerated concrete is more accessible;
• Frost resistance. Aerated concrete has an increased resistance to negative temperatures, which is necessary for the use of building materials in regions with a harsh climate. This is due to its ability to withstand repeated freezing followed by thawing without losing its integrity;
• Fire resistance. Given that gas silicate also has good resistance to fire, aerated concrete has the best resistance to elevated temperatures, as well as open fire.

Considering the difference between gas silicate blocks and aerated concrete blocks, it is worth noting that both types of materials, when used correctly, provide a long period of operation of the building.

Which block to choose for construction

Determining what is best for building a house, experts recommend choosing gas silicate, which is superior in many respects to aerated concrete. This is due to the fact that silicate materials are made at special enterprises, where product quality is closely monitored. For this, special equipment is used, as well as laboratory tests. But this affects the price, which makes the material more expensive.

Many multi-apartment developers, due to greater availability and low hygroscopicity, prefer aerated concrete. It is used for the construction of walls in monolithic frame structures. The use of each material is possible for the same purposes, subject to compliance with technological requirements. In total, such products are used in the following areas:

• Low-rise housing construction;
• Construction of industrial or commercial facilities;
• Construction of sports facilities;
• Construction of public buildings.
• The scope of such blocks is determined by weight and strength:
• Heavy options with a high density can be used to build solid walls or partitions in low-rise construction;
• Average in terms of product performance is structural and heat-insulating. Therefore, they are used for the construction of private small houses or cottages;
• Products with low strength are preferably used to create thermal insulation, and their use for the construction of loaded structures is prohibited.

The difference between aerated concrete and gas silicate is the technology for creating such blocks and their main characteristics. Everyone determines for himself which building material is more preferable for the construction of a particular building. It is important to be based on the technical characteristics of materials and financial possibilities.

The construction of a house is associated with a constant choice: the project, the number of storeys, the materials used, etc. The reliability of the family hearth will depend on the correctness of the decisions. A cold house with an ever-leaking roof can become a constant strife in the family. To avoid unpleasant situations, a preliminary consultation at the initial stage of construction with architects and other specialists who will help you choose the material will help.

Recently, cellular concrete has been increasingly used. It is suitable for those who want to build a heat-saving and reliable housing in the shortest possible time. Among the variety of this material, foam block and gas silicate are distinguished, so it will be useful to find out what are their similarities and differences.

Differences

gas silicate blocks include Portland cement, sand, calcareous lime, water, blowing agent- aluminum powder and surfactant - sulfonic acid C. To obtain this product, only production conditions and high-tech equipment are used. From the above components, a monolithic layer of a given thickness is formed, and then it is cut into blocks of the desired size.

On the video - the use of foam concrete:

About what are the pros and cons of baths from expanded clay concrete blocks, as well as about the differences with the foam block, you can find out from this

Also, floors are often made from them in private houses and apartments. For greater comfort, foam concrete of different densities is used, and a layer of thermal insulation is laid between them. They are also used to decorate buildings that were built with bricks.

Despite some similarities with foam concrete, gas silicate still has high strength characteristics, which are used for thermal insulation of buildings and heating networks. It is well fastened and often ventilated facades are erected with it.

On the video - the use of gas silicate:

You can learn about which floor to use in an aerated concrete house from this

Summing up, we can say that it is more expedient to use gas silicate in multi-storey construction of capital structures. And foam concrete is better and more economical to use when laying utility rooms and cottages. Both materials can be used for interior partitions. The final decision in favor of one of them should be made after consulting with experts in their region, who will tell you which blocks will perform better in certain climatic conditions.

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When choosing one or another material for the construction of walls, it is by no means possible to say unequivocally that some of them are better and some are worse. Cellular concretes, such as aerated concrete and gas silicate, are no exception. Each of these materials has its own advantages and disadvantages, which, to one degree or another, can significantly affect the choice between them.

So, in order to answer the question - “Which is better?”, It is necessary to understand what each of the materials consists of, and then carefully study all the main comparative characteristics of both aerated concrete and gas silicate in general, which we will now do.

To begin with, it must be clarified that none of these materials is practically used in construction as monolithic concrete. As a rule, ready-made blocks of various sizes are made from them, from which walls for various purposes are built.

Structure and appearance of concrete - first comparisons

As already mentioned, aerated concrete and gas silicate belong to the class of cellular concrete. And this means that their structure is very similar, both external and internal. In most cases, because of this, they are often confused, and sometimes it is believed that they are one and the same, but this is far from the case, the gas silicate block has slightly different technical characteristics from aerated concrete.

Despite this similarity, there are still external differences between aerated concrete and gas silicate, first of all - color. The first is characterized by a whiter color, and aerated concrete has a dark gray tint.

Another important difference is their production. In aerated concrete, as in most block materials, the main connecting link is cement, which gives it a gray tint, and in gas silicate - lime.

Unlike aerated concrete, the manufacture of gas silicate without hardening in autoclaves is not permissible. The production of aerated concrete, in turn, allows the natural hardening of the material in the fresh air.

The structure of aerated concrete and gas silicate, as already mentioned, is very similar and consists of many cells with air, thanks to which the walls retain heat very well.

Attention! The grade strength of concrete directly depends on the number and size of air pores. The smaller the pores, the higher the strength, but the heat-insulating properties, in this case, are significantly reduced.

So we examined the external similarities and differences of concrete, now let's start comparing the characteristics of both materials.

Comparative table of aerated concrete and gas silicate

To begin with, let's look at the table of characteristics of both concretes, and then we will analyze all the parameters in more detail.

Since aerated concrete, as well as gas silicate, have many different grades in terms of strength and density, we will compare the average values ​​​​of the characteristics of these materials not in numbers, but using the “better - worse” method:

It is worth noting that all the main disadvantages of gas silicate blocks are very similar to the disadvantages of aerated concrete, so we will not consider them separately.

As can be seen from the table, some characteristics are better for gas silicate, and some for aerated concrete. Let's take a closer look at them:

1. Due to a more uniform distribution of pores (voids), gas silicate has a slightly greater strength compared to aerated concrete.
2. The aerated concrete block weighs a little more than its counterpart, which will slightly complicate the masonry and give an additional load on the foundation under the house.
3. The thermal insulation properties of gas silicate are also slightly better than those of aerated concrete.
4. In frost resistance, aerated concrete is significantly superior to its competitor, mainly due to lower water absorption, since water and frost are the worst friends for any building material.
5. Due to the same, more uniform distribution of cells, the thermal insulation properties of gas silicate are better.
6. The geometry of gas silicate blocks is more strictly maintained, which will slightly reduce the consumption of masonry adhesive and plaster material, compared to its competitor.
7. The color of gas silicate blocks is more pleasant, and the house built from them looks more aesthetically pleasing (of course, without external decoration).
8. In terms of fire resistance - aerated concrete has slightly better performance.
9. Durability is generally a separate issue, because both materials have become widely used relatively recently, and there is no practical evidence of durability. I think that when used correctly with respect for technology, the performance will be almost the same.
10. And finally, the financial side of the issue. Blocks of the same volume from gas silicate are more expensive than from aerated concrete. This is due to the more complex manufacturing process.

The laying of walls from gas silicate blocks is similar to the laying of aerated concrete on glue, it is difficult to give preference to anyone here, but still, due to the more correct geometry, it is a little more pleasant to work with gas silicate. Although in the cost of the masonry itself, as a rule, there is practically no difference.

What building material do you prefer?

Analyzing all of the above, we can conclude that gas silicate has slightly more advantages over aerated concrete, and this is not surprising. Gas silicate is produced on more high-tech equipment, and is a more modern building material. But this in no way means that aerated concrete is not suitable for building houses.

Aerated concrete also has its own advantages, such as water absorption, fire resistance and price, which, today, plays an important role in choosing between them.

I hope that this article will help you determine what is best for you - aerated concrete or gas silicate, depending on your needs and capabilities. And the choice in favor of one or another building material will be correct and logical.

The optimal solution in the field of low-rise construction is the use of economical gas silicate or aerated concrete blocks. Everyone should make a choice in favor of one or the other on the basis of a thorough study of the material, an analysis of the advantages and disadvantages.

Structure and appearance of concrete

Aerated concrete and gas silicate are cellular concretes, so both products are similar in appearance and structure. Both materials consist of a large number of air-filled pores, thanks to which the walls have high thermal insulation properties. The number of cells determines the grade of blocks in both cases - the smaller, the stronger the block. However, higher strength grades lose in thermal insulation.

The gas silicate is white in color due to the lime used as a filler. Aerated concrete has a dark gray tint due to the use of cement as a binder.

Production features

Aerated concrete blocks are made from a mixture of water with cement (50-60%), sand, lime and aluminum powder, which works as a blowing agent. Blocks harden naturally or by force. The second method increases the strength, reliability, thermal insulation of the finished product.

Gas silicate blocks are prepared from 62% sand, 24% lime with an admixture of aluminum powder during autoclave hardening.

General characteristics

The distribution of pores in gas silicate is more uniform than in aerated concrete, therefore its strength and thermal insulation properties are somewhat higher. The mass of the aerated concrete block is greater, so its masonry is more complicated and requires a more powerful foundation. Autoclaved concrete has precise geometry and is therefore considered more economical by reducing the consumption of masonry adhesive and finishing materials. Gas silicate masonry walls are smoother, easier and faster to build.

Gas silicate thermal insulation is superior. In frost resistance, it is inferior to aerated concrete, since the latter has a lower degree of water absorption. Due to the fact that it allows water to pass through without absorbing it, a favorable microclimate is created in the house. Gas silicate, on the contrary, is able to absorb moisture, from which it gradually begins to break down.

The white color of gas silicate blocks looks aesthetically pleasing, so the walls do not need additional decorative finishing. The fire resistance of aerated concrete is higher, although in terms of sound insulation it is inferior to gas silicate. The durability of both materials is difficult to assess, as they have been used relatively recently. One volume of gas silicate blocks upon purchase will cost more than aerated concrete, due to more complex manufacturing technology. Although the cost of the masonry itself from both materials is almost the same.

Material Comparison

To compare both building materials in detail, you should familiarize yourself with the main advantages and disadvantages of one over the other.

Advantages of gas silicate over aerated concrete

The raw material composition of the blocks determines their properties, which are the main parameters for comparison. The uniformity of distribution of the formed air bubbles depends on the interaction of the components of the raw material. In this, aerated concrete products are inferior to gas silicate blocks. Due to this uniformity, the strength of the autoclave block increases, so the walls from it practically do not shrink and do not crack. This quality determines the possibility of using gas silicates in the creation of load-bearing partitions, the construction of high-rise buildings. At the same time, the density of the material is 600 kg/m3 and higher. A two- or three-story house can be built from aerated concrete only if its density is 800-900 kg / m3.

The more homogeneous structure of the gas silicate product increases its noise insulation properties, therefore, when building buildings with good noise protection, this material should be chosen. Thanks to autoclave processing, gas silicate blocks have a more even and smooth surface in a pleasant white color. Wall material can not be decorated, which will save on finishing. In terms of heat and sound insulation characteristics, gas silicate is slightly superior to the second product. It also saves on consumables.