Gas silicate blocks - disadvantages and dubious qualities. All the advantages and disadvantages of gas silicate blocks Gas silicate blocks pros and cons

Gas silicate block is a fairly new “representative” of the construction industry, it became known not so long ago, but has already been able to establish itself as an inexpensive, “people’s” building material that can be used in the construction of any construction project.

It’s a pity, but, alas, the perfect building material has not yet been invented. Any of the existing building materials has both positive and negative indicators. We propose to dwell on the main advantages and disadvantages of these blocks, without trying to present them in a better light.

Advantages gas silicate blocks

Thermal and sound insulation. They occupy first place among materials with low thermal conductivity and low sound transmission. This is due to the presence of a bubble structure in their structure. After all, it is a known fact that air is one of the strongest heat retainers. Indeed, as the number of bubbles (density) increases, the thermal insulation of the material increases.
Durability. This material is not of interest to rodents, which cannot be said, for example, about wood and various types bricks In this regard, walls made of gas silicate are not afraid of destruction caused by these animals.
Environmental friendliness. Gas silicate blocks environmentally friendly. They do not contain dangerous chemical components. Walls made from them do not pose a danger to the health of residents. In addition, the construction of dwellings from this material does not cause much harm environment, when compared, for example, with wood, for which forests are cut down.
Low cost. Building houses from this material is cheaper than using wood or brick. The solution for creating a block has a fairly simple composition and is unpretentious to work with. Accordingly, the price of the resulting product is very reasonable.
Ease of processing. Gas silicate blocks lend themselves well to cutting and, in some cases, drilling due to their light porous composition. The process of building the wall itself is also not difficult. The blocks, although voluminous, are not heavy. Therefore, the raising of the walls is quite intensive and with minimal labor costs.
Low weight. Since a gas silicate block has a porous composition, it is much lighter in weight than, for example, a brick. Despite this, builders do not advise saving too much on laying the foundation, believing that the process can actually be made quite cheap. A gas silicate block requires a reliable strip base to ensure optimal foundation of the walls.

Flaws gas silicate blocks

Fragility. The inside of the block is not too dense, the reason for this is the porosity of the composition and the presence of air bubbles. These units should be transported, moved and used very carefully. Alas, even a minimal blow can split the block, cracks form and the material becomes unsuitable for construction. In addition, builders advise using a reinforced concrete belt as insurance, which will provide additional durability.
Low-rise construction. Gas silicate blocks are afraid of heavy loads. For this reason, this material is not used in the construction of multi-storey buildings. The building should be no higher than 1-2 floors.
Fear of moisture. One of the significant disadvantages of the material is moisture resistance. Because of it, the gas silicate block loses its strength characteristics and collapses. In this regard, block walls must be finished inside and outside. The best way- plastering using thermal insulation material.
Building restrictions. It is impossible to build from this building material, for example, a bathhouse, sauna, etc. This is due to the fact that the material is afraid of increased moisture. In this case, it is more appropriate to use brick.
Shrinkage. Walls made of this material may shrink after some time. As a rule, shrinkage appears 20-25 days from the moment the wall is built. Until this point, the wall should not be plastered. This is due to the fact that if Finishing work carried out directly after installing the blocks, splits and ruptures may occur as a result of shrinkage.

Gas silicate blocks are...

As you know, a gas silicate block is essentially foamed concrete, the structure of which resembles cells. The production of this block in the industrial sphere is carried out in a special autoclave oven, where cement, sand, lime and aluminum chips are mixed, after which the mixture hardens at a certain temperature and pressure. By the way, it’s pressure that plays a role main role in obtaining a strong and dense structure of this block.

From the above it is clear that gas silicate blocks, despite all the disadvantages, have a huge number of undeniable advantages. All the shortcomings of the material can be easily eliminated by using the latest materials used for finishing. Thanks to gas silicate blocks, it becomes possible to build a warm, reliable and strong house at a very attractive price!

IN Lately Gas silicate blocks have become very popular, the pros and cons of which depend on their characteristics. This finish has properties similar to artificial stone, but at the same time differs in some parameters in better side. Strengths gas silicate blocks helped them gain distribution in the building materials market.

Composition and types of gas silicate

Gas silicate block is a material that can be used for the construction of main and additional walls, fences and other structures. It belongs to the type of cellular concrete and is made on the basis of the following elements:

Binding mixtures.
Powder containing aluminum.
Special fillers.
Water.

Lime is added to the composition of such blocks, which guarantees interaction with the foaming agent. Finished products cut into shapes with different sizes: length is usually 60 cm, height can vary from 10 to 50 cm, thickness approximately 20 cm.

Gas silicate can vary quite a lot depending on density. The following options exist:

Structural grade D700 or higher. This type is used in the construction of main walls.
Structural and thermal insulation with level D500-D Can be used for the construction of fences and walls of 2-story buildings.
Thermal insulation grade D is used not for the construction of walls, but to improve the heat capacity of already constructed surfaces.

Gas silicate-based blocks can be used for private construction of low-rise buildings and buildings production type, insulated houses, combined structures.

Advantages of using gas silicate

The advantages of gas silicate blocks include the following characteristics:

These advantages helped the material become widespread. But gas silicate blocks also have weaknesses.

Disadvantages of using gas silicate

Despite a large number of This material also has advantages and weaknesses that will definitely need to be taken into account during construction. The disadvantages of gas silicate blocks include:

Cement-sand mortars cannot be applied to the surface of such material. They will not adhere well to such a surface and will fall off. Experts recommend using gypsum compounds, but you will need to take into account a certain nuance. Such plaster mortar will not be able to hide the seams on the walls, and with the onset of winter, the surface will begin to crack. This is due to the fact that the gypsum mixture is not protected from humidity and changes in temperature.

Pros and cons of houses made of gas silicate blocks

Manufacturers of such building finishing claim that buildings based on gas silicate can be compared with wooden buildings in terms of microclimate. At the same time, the construction procedure is not particularly complicated or labor-intensive, so all work can be completed without the involvement of specialists and in a short time.

This material is able to guarantee an acceptable rate of heat and air exchange, this is possible due to the porous surface of the gas silicate. It’s quite warm inside the building during cold weather, but waterproofing will be necessary to maintain the temperature. To ensure that the surface can breathe, you will need to cover it using foam plastic.

The simplicity of construction procedures depends on the geometry of the material. If the blocks are smooth, then erecting the building is quite easy. During the construction process you will need to use special glue. Application cement mixture will lead to the formation of large seams. Because of this, the thermal conductivity and strength of the surface will be significantly reduced. Due to the heaviness of the blocks, it will be quite difficult to do the work yourself; you will need help.

During construction you will need to take into account a number of the following nuances:

This material is ideal for the construction of 2-story buildings, but no more. If the load on the blocks is too great, the material may not withstand and collapse.
After constructing the first floor of the house, it is necessary to make a monolithic strapping belt. Only this will allow the weight of the second floor and roof to be evenly distributed across lower levels. The 3rd row of finishing will need to be reinforced using a mesh based on metal or sheets.
Monolithic strip foundations must be used as the basis for such substrings, so it will not be possible to save money during the construction process.
The constructed walls shrink over the course of a year. This nuance must be taken into account when planning internal lining surfaces. Due to shrinkage, plaster can quickly crack, so it is preferable to use drywall.

Aerated concrete in last years has become one of the most popular materials for masonry walls. The blocks are used both in private construction and on an industrial scale. Individual developers use them to build houses, garages, bathhouses, and utility rooms for various household needs. In the second case, gas blocks are used to construct partition walls between rooms (premises) inside multi-storey buildings.

Experts have mixed opinions about the pros and cons. The difference in assessment is due to the relative short term its mass application. Therefore, it is too early to make generalizations. No basic research behavior of aerated concrete blocks over several decades. Observations and measurements are carried out relatively recently. The overall picture is formed by reviews of private developers who do not always comply construction technologies and blaming “poor quality material” rather than their own unprofessionalism and negligence.

At the same time, the quality of gas blocks that were produced 5-8 years ago and modern ones is radically different. Now there are dozens of companies on the market offering truly reliable building materials. One thing is certain: modern blocks is an affordable and reliable wall stone, quite suitable for the construction of objects with a service life of about 50-80 years.

General overview and features

First, you should study the composition of aerated concrete. Blocks are produced based on the following components:

cement (from 50 to 70%);
sand (20-40%);
lime (5%);
water (less than 1%);
special additives (0.05-0.1%).

The mixture is poured into molds heated to 40 °C and sent to the autoclave. Aerated blocks suitable for masonry are manufactured only in large enterprises where there are chambers in which a pressure of up to 12 bar is created and a temperature of about 2000 ° C. The mixture contains aluminum powder, which activates rapid gas formation. It is this additive that makes autoclaved aerated concrete a cellular (porous) material. Air bubbles in the structure of the stone determine the thermal insulation characteristics and allow it to “breathe”.

After the aerated concrete mass has completely hardened, it is cut using strings into blocks of certain sizes and configurations. High-quality stone, produced in compliance with technology, is characterized by ideal precision of lines. Regular parallelepipeds stacked on top of each other provide thin seams between the rows of the wall being built. Cold bridges can be avoided, thereby significantly reducing the heat loss of the building.

Blocks that have not been autoclaved are also sold. They are dried in hydration boxes under conditions of elevated temperature and humidity. Accordingly, the strength of concrete is 3 times less than that obtained using the autoclave method. This type aerated concrete is suitable for insulation, but not for masonry.

And the quality of blocks made by hand is very low. Reviews about them are a continuous stream of negative statements. But, given the fact that in each of the three production options ready material is called “gas block”, consumers make a generalization. Accordingly, an opinion is formed that there are much more minuses than pluses. In fact, high-quality aerated concrete has very few disadvantages. Experts in their reviews indicate that with the correct arrangement of the foundation and compliance with technology, the operational parameters of the blocks are not much inferior to brick or cinder block.

Technical characteristics of blocks

1. Dimensions.

Standard linear dimensions parallelepiped blocks:

length – from 500 to 600 mm;
height – 200 mm;
thickness - from 75 mm to 500 mm.

2. Configurations.

They are produced in the form of parallelepipeds with 6 smooth surfaces or with grooves and ridges on 2 end faces. U-blocks are also produced for arranging armored belts.

3. Strength of aerated concrete.

The material is lightweight, but at the same time has good strength. Depending on the brand, the compressive strength coefficient ranges from 1.5 to 3.5 kgf/cm².

4. Classification of grades depending on the density of aerated concrete:

D300-D500 – thermal insulation;
D500-D900 - an intermediate option used for structural and thermal insulation work;
D1000-D1200 – structural aerated concrete.

Advantages and disadvantages

All of the above properties of aerated concrete blocks should be taken into account during construction. Depending on the type of future building (house, bathhouse, garage), you can use wall stone various sizes and density.

Of course, there are pros and cons aerated concrete blocks, produced both by autoclave and obtained by drying in hydration chambers. But in the first case, the declared properties practically coincide with the operational ones, and in the second, the material may behave “inappropriately”. After all, the parameters are designed for one climatic conditions, and developers make their own adjustments, not taking into account expert reviews on construction from aerated blocks.

1. Advantages of aerated concrete:

Ease of processing.

Using a tool, gas blocks can be easily processed manually. You can saw, make recesses, grind surfaces.

Thermal insulation properties.

Using D500 and D600 brand blocks, the developer achieves two goals at once: constructing the frame of a house or bathhouse, as well as thermal insulation of these buildings.

Soundproofing.

The ability to soundproof directly depends on the brand of aerated concrete blocks and the thickness of the walls.

Fire resistance.

Aerated concrete blocks are non-flammable material. They have highest class fire resistance.

Environmental friendliness.

Gas blocks are safe. Aerated concrete can be harmful to health in one case - if there is radioactive elements in the base mixture. But this is practically impossible on an industrial scale when the components undergo laboratory testing. During operation, the blocks do not react to form toxic substances. According to their own environmental characteristics aerated concrete is comparable to natural materials and is not much inferior to wood.

Light weight.

It is very light, so it is easy to work with. You can do the laying yourself.

Large product size.

This option should also be considered a plus. The construction of houses made of aerated concrete is carried out much faster than similar houses made of brick.

Resistance to biological effects.

Aerated blocks are an environment unfavorable for the formation of mold, fungal colonies and bacterial growth. The material does not need to be treated with antiseptics.

2. Disadvantages and negative parameters:

Fragility.

This disadvantage of the block manifests itself during transportation, during the laying process. But the main point is the predisposition to cracking of the walls in the event of improper foundation arrangement. Small irregularities in the strip base - and after 2-3 years the blocks will begin to crack. The problem can be solved by using mesh reinforcement at intervals of 3-4 rows.

High water absorption coefficient.

It can be reduced with special impregnations, which are applied before plastering. It is strictly not recommended to leave aerated concrete walls “open”.

Problem with fasteners on aerated concrete surfaces.

Massive shelves, cabinets and other objects are very difficult to mount on the wall. The best solution– self-tapping screws. But they have their own nuance - oxidation, and as a result, loss of aesthetic appearance.

The frost resistance parameter is overestimated by sellers.

Some experts claim that the real frost resistance of D500 blocks is only 25 cycles. Although sellers declare at least 50 (this is the indicator that is suitable for exterior finishing). Frost resistance at the F50 level is observed in gas blocks of grades D600 and higher.

Presence of free lime.

This deficiency leads to active corrosion processes occurring inside aerated concrete. Lime corrodes sections of pipes, fittings, jumpers and other metal elements.

To build or not to build with aerated concrete?

This question very often arises among individual developers. On the one hand, the material has many advantages, and on the other, no fewer disadvantages. The relative cheapness of the blocks is compensated by the “lottery” in terms of the durability of the building. It is unknown how long a house made of aerated concrete will last if deficiencies in the foundation or masonry are suddenly discovered.

Developers are actively discussing the disadvantages of aerated concrete baths. These include the properties of the material to actively absorb moisture. But the use of impregnations and primers, as well as waterproofing finishing is good decision in this case.

Savings on foundations also speak in favor of houses, garages or bathhouses made from aerated blocks. For future construction, a massive monolithic slab is not required; a strip base is sufficient. Accordingly, it can be built on any type of soil.

You need to start constructing a building from aerated concrete by first weighing the pros and cons. In this case, it is important to take into account all factors (location, soil type and freezing depth, relief, number of storeys). Even in the case of a light structure (garage, bathhouse), you need to adhere to technology so that in a few years you do not witness the destruction of an almost new building.

Continuing the topic of building materials based on concrete and various additives, we will analyze such a popular material as gas silicate blocks. Many advantages, as well as versatility of use, have brought this material highly popular in many regions of the world, including in our country.

The blocks are based on high-quality cement, gypsum, lime and water. All these materials are mixed together, after which aluminum powder is added to the solution. The latter reacts with lime, causing the release of gas and the composition is filled with small pores. Modern technologies allow you to adjust the size of the pores.

After mixing the material, pouring it into molds and cutting the latter, the blocks are sent to autoclaves, where they undergo the final strengthening and impart those performance characteristics for which gas silicate is valued. However, there is also a non-autoclave production method, but in this case gas silicate blocks are less durable and less environmentally friendly.

Advantages of gas silicate blocks

The gas silicate block has high compressive strength. It's reliable construction material, which will make it possible to obtain strong load-bearing or interior walls. Naturally, we're talking about on load-bearing structures in low-rise construction;
Ease. Aerated concrete is five times lighter than conventional concrete and has high strength. Light weight not only facilitates construction, but also makes it possible to save time and money on the construction of a massive foundation;
The material is 8 times superior to ordinary concrete in terms of thermal insulation properties. IN winter time you will spend less resources on heating even if you save on wall insulation during construction;
The porous structure makes the gas silicate block an order of magnitude more effective sound insulator than brick;
Such blocks are mainly manufactured by highly qualified professionals. So the quality of the product is usually very high. The deviations are minimal, so when correct masonry, the walls will be as smooth as possible;
For rodents, gas silicate blocks are of no interest;
Large sizes allow you to build walls much faster than with brick. At the same time, you can work independently. By following a number of simple rules, you can build a structure from these blocks without much knowledge in construction;
The material is completely environmentally friendly and is not subject to fire;
High vapor permeability allows for complete gas exchange, creating a pleasant microclimate in the premises.

Disadvantages of the material

Hygroscopicity, as is the case with other options for cellular concrete, is very high for gas silicate blocks. Having absorbed a lot of water, such a block becomes susceptible to destruction and loses its performance characteristics, and also provides the fungus with an excellent environment for reproduction. As a result, additional waterproofing measures are required;
Low strength. When attaching heavy structures to walls, it is necessary to use special dowels;
Mediocre frost resistance, which also increases the cost of protective measures;
Shrinkage of these materials can be quite significant. For this reason, every three to four rows it is better to use reinforcing mesh or reinforcement. Otherwise, the walls may crack over time;
As is the case with all porous concrete, thermal insulation properties decrease as strength characteristics increase.

Glue or cement?

Laying of gas silicate blocks is done either with a standard cement-sand mortar or with specialized glue. What to choose? First of all, it is worth noting that both fastening agents have higher thermal conductivity than the gas silicate blocks themselves.

On the cement side the cost is several times lower. The disadvantage is the large thickness of the layer, which increases the width of the cold bridges. The glue allows the blocks to be almost end-to-end, which is very good. However, to lay the first layer of blocks directly on concrete base Cement mortar will still be needed, as it will allow for the necessary leveling in this case.

Technology for laying gas silicate blocks

We will describe the construction of a foundation, which can be strip, in more detail in another article, since this topic is very large. As for the actual laying of blocks, the first row is placed on concrete mixture from the highest corner of the foundation. If necessary, we make additional adjustments using a solution. Use levels.

Important! The high ability of the gas silicate block to absorb water should be taken into account when installing the first row of blocks on the solution. To prevent moisture from the latter from being absorbed into the block, the lower part of the block is wetted with water before installation on the concrete support.

All other rows can be laid with special glue. In this case, every three or four rows the walls should be reinforced in order to reduce shrinkage.

Precast concrete slabs cannot be laid directly on this type concrete blocks due to their insufficient strength. In this case, it is necessary to build a reinforced concrete belt around the perimeter of the wall, made using the technology monolithic construction. When constructing two-story and higher houses, reinforced concrete bearing structures required. In addition, reinforced concrete belts require thermal insulation;
The strength of the block is one of the determining factors. If you are building a one-story structure, you will need a block with a density of at least half a ton per cubic meter. If we are talking about the construction two-story houses, then you need to choose options of 600 kilograms per cubic meter. We have already said that as strength increases, the insulating qualities are lost, so walls made from such a block must have a minimum of 40 centimeters in thickness. Otherwise, additional insulation will be required. It is impossible to build a base from such blocks;
Chips and other damage to the blocks are not allowed. Since the material is fragile, it must be transported, stored and handled carefully. Try to buy more blocks than necessary, as some may get damaged. Blocks need to be cut special tool and as carefully as possible.