Building a house, like any other building, requires the adoption of many important decisions. And one of the most crucial moments is the choice of the optimal building material.
Currently, houses are built from a variety of various materials, the most popular of which are brick and aerated concrete blocks. To understand which material to choose, you need to separately consider the main features of brick and gas block, and then compare their most significant characteristics for the developer.
Features of brick as a building material
Two types of bricks are used for construction, namely silicate and ceramic. The first type of brick is made from lime, sand and water. The process of their manufacture is quite simple: special forms are loaded into an autoclave, where they undergo heat treatment. Such processing is carried out at a temperature of about 200 ° under the influence of saturated steam of water under pressure.
Silicate brick is made from lime and sand and is one of the most ancient building materials. The main advantage of such a brick is that it is environmentally friendly, durable and has excellent sound insulation performance. Silicate brick is ahead of ceramic in density, and its frost resistance and strength are noticeably higher than that of currently existing lightweight concrete grades. To make it clearer, construction companies guarantee that the walls, for the construction of which such bricks were used, will stand for at least 50 years. At the same time, the building will be resistant to various atmospheric phenomena, unpretentious in maintenance and undemanding in repair. Walls will retain their original color for a very long time, unless they are exposed to prolonged exposure. high humidity.
With all these advantages, silicate brick is characterized by low heat and water resistance, so it is not suitable for the construction of furnaces and chimneys, sewer wells and foundations.
ceramic brick has also been on the building materials market for a long time. Mankind learned to make it more than 4 thousand years ago. In Russia, burnt brick became known much later - around the beginning of the sixteenth century. Throughout its history, ceramic bricks have earned a reputation as a reliable and durable building material. The production technology was improved and changed depending on the requirements of the time. This material is valued primarily for its durability and high strength.
Made using clay. Depending on the composition of the feedstock, ceramic bricks can be of several types. The clay is fired in a special drying chamber. For each clay, individual firing technologies have been developed, the duration and temperature of which determine the frost resistance and strength of the finished product.
There are 2 types of such bricks: ordinary and front. The method of making an ordinary was given above. The front one is made in accordance with special technology. Special conditions make it possible to obtain high-strength bricks with excellent resistance to adverse external influences.
Each of the considered species is highly resistant, durable and frost-resistant. Clay ceramic brick practically does not absorb water, and if it does, it dries out rather quickly without accompanying deformations. In addition, it is characterized high density which makes it capable of withstanding heavy loads.
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The main features of the blocks
The gas block is rapidly gaining popularity in the building materials market. Blocks have many advantages, but before considering them, you should understand what constitutes given material.
Aerated concrete blocks are made of aerated concrete - one of the varieties cellular concrete, which is artificial material and has air pores throughout the body. An ordinary gas block is made from cement, lime, sand, water and aluminum powder. There are technologies that allow the production of blocks using various industrial waste: slag, ash, etc. This contributes to a significant reduction in the final cost of the gas block, but worsens its quality.
Blocks are very easy to make. The composition prepared in accordance with the instructions is mixed with water and poured into molds. Aluminum powder reacts with lime, hydrogen begins to be released, and it is due to this that pores form. As a result, the mixture rises like yeast dough and gains firmness. This mass is cut into separate blocks. They are sent to the autoclave, where they finally reach under pressure.
The gas block is a relatively young material. The blocks have a porous structure, which provides good thermal insulation qualities. These characteristics significantly exceed those for bricks and heavy concretes. The blocks have physical properties, which allow you to compare them with wood. It is a warm, environmentally friendly and breathable building material. It can be drilled and sawn without difficulty. Unlike the same tree, the blocks are resistant to fire and decay.
Aerated concrete blocks are characterized by fairly high strength and can be used for the construction of various structures. Gas blocks allow you to build walls of various thicknesses and with different thermal conductivity. However, it is impossible to build buildings above three floors exclusively from blocks.
On average, the weight of a gas block is 22 kg. Its dimensions are much larger than bricks. To get masonry of the same size, you will have to take about 64 kg of bricks. At the same time, gas blocks have a much higher rate of sound insulation. The material does not burn and does not emit toxic substances when heated.
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Comparison of the main technical characteristics
To make it easier to understand the choice, you need to consider the main characteristics of each of these materials and compare them. To the number significant characteristics include the following:
- Ultimate compressive strength. For aerated concrete blocks, it can reach 50 kg / cm². According to this indicator, ceramic bricks are almost 2 times ahead - 110-120 kg / cm².
- Weight 1 m³ wall. The walls of the gas block will weigh from 200 to 900 kg. If the wall is made of bricks, the weight of 1 m³ will reach 1.2-2 tons.
- Thermal conductivity. Aerated concrete blocks have a thermal conductivity of 0.09-0.12 W / mK. For a brick, this characteristic is 0.32-0.46 W / mK.
- Frost resistance index. Aerated blocks can withstand an average of 50 freeze and thaw cycles, and bricks - about 80-100 cycles.
- Water absorption. Aerated concrete has a water absorption index equal to 20% of the mass, brickwork - about 8-12% of the mass.
- Fire resistance. This setting is the same. Both gas blocks and brickwork are of the lowest class, i.e. one.
- Single item size. The size of a standard gas block is 20x30x60 cm, the size of one brick is 6.5x12x25 cm.
- Number of products in 1 m³: 28 blocks of aerated concrete, brick - about 380 pcs.
- Masonry weight. A cubic meter of gas block masonry will weigh an average of 400 kg. Similar - about 1800 kg.
Given these characteristics, you will be able to navigate and understand which material is best for you. It is important to take into account not only the affordable budget and ease of use, but also the conditions in which the building will be operated. For example, between summer cottage in the southern regions and a solid three-story house somewhere in the north, the difference is very large, as are the requirements for building materials. Each of the listed indicators to one degree or another will affect stability, durability and other important characteristics. finished building so they all need to be taken into account.
Starting construction capital house, each developer is trying to determine for himself the economic component of the construction and choose the most suitable building material for this. After all, I want the house to stand, and at the same time fairly new building materials were used. Today, most often choose aerated concrete or brick for construction. Materials of block type, but having different technical characteristics in most parameters. Therefore, in the material we will try to figure out what is better and more profitable to build - houses made of brick or aerated concrete. We will evaluate the properties of materials and consider all the nuances of building from one type of block or another.
Gas block and brick: definition and production technology
Brick is a block building material made from clay with the addition of plasticizers. As a result, the resulting clay mass goes through the firing stage, which strengthens the finished brick hundreds of times. Brick blocks have been used in construction for more than 300 years, and therefore the result of durability, resistance and bearing capacity can be determined today by buildings built of brick more than 100 years ago. That is, brick is a fairly predictable building material.
Important: while aerated concrete was first used in construction a little over 80 years ago. Therefore, it is difficult to accurately determine the durability of the material. No one knows how he will behave in 100-150 years.
Aerated concrete is produced from a mixture of cement, sand, lime and gas-forming substances with the addition of water. As a result of the reaction cement mixture foams and pours into molds. Then the blanks are dried at a certain temperature. As a result, the formed pores of the gas are preserved, which makes the blocks of aerated concrete relatively light.
Having understood the production technology of both types of materials, one can have an idea of the formation specifications blocks. And understanding them, you can determine for yourself what is better in construction.
Comparative characteristics of both types of blocks
It is possible to compare building material in the form of brick and aerated concrete according to numerous parameters, such as moisture resistance, strength to mechanical stress, frost resistance and thermal insulation, mass, etc. Let's try to take everything apart in order to form our attitude to aerated concrete and brick as building materials.
Mass of blocks
First of all, the weight of the building material is of great importance. After all, laid out in a box, it will form a sufficient mass, and that, in turn, will put pressure on the foundation. From here it is necessary to lay the bearing capacity of the basis at the design stage of the house. So, aerated concrete is lighter, since it has a porous structure. It is worth noting that 1m3 of a laid aerated concrete wall will weigh 400-900 kg, depending on the thickness of the masonry. Thus, when building a house, it is possible to arrange a lightweight type of foundation - a shallowly buried strip or columnar one, which will save the construction budget. Yes, and labor costs for distillation of walls from aerated concrete will be less. Here, a box at home can be driven out within a month.
Brick has a large mass, unlike aerated concrete, due to its dense structure. So, the mass of 1 m3 of a brick wall is 1300-2000 kg, also depending on the thickness of the masonry. Thus, it becomes clear that brick house it is required to mount a strong recessed strip foundation or slab monolithic. Since light bases will not withstand the load of such a house. Hence the construction costs.
Important: the volume of the material also matters. So, in 1 m3 of aerated concrete - 28 pieces, while bricks with the same volume - already 513 pieces. Accordingly, the labor costs for laying a brick wall will be large. Such a box is built within 3-4 months.
Thermal conductivity of blocks
An important factor that affects the role of the choice of the developer. After all, I want to build not just a house, but warm house at lower cost. Therefore, when choosing, keep in mind that the thermal conductivity of aerated concrete is much lower than that of bricks. That is, aerated concrete blocks perfectly retain heat in the house and do not conduct it outside. brick more cold material and therefore for construction it is enough warm walls you will need to make masonry at least 50 cm thick, which increases material consumption. An aerated concrete wall with the same thermal conductivity as a brick wall of 50 cm can have a thickness of 35-40 cm. That is economical consumption building material in the form of aerated concrete is available.
Water permeability of the material
But here we also pay attention to the water absorption of the blocks. So, brick is a more moisture resistant material due to the absence of a porous structure. Note that brick absorbs moisture only by 6-16%, while aerated concrete absorbs water by 100%. That is, blocks of aerated concrete must be additionally protected from the outside. facade decoration, and this is an additional cost for construction. Brickwork does not need outer cladding because brick blocks are not afraid of water. By the way, the feature of aerated concrete to absorb water makes its own adjustments to the construction. So, work can only be done in a dry and relatively warm weather or securely defend construction site rain canopy.
Important: if aerated concrete is not protected from moisture, then mold and fungus will grow in the blocks over time, which will lead to the destruction of the house in the future.
Frost resistance of blocks
Based on the water absorption of the blocks, one can also talk about their frost resistance, that is, the number of freezing / freezing cycles. This factor also affects the durability of the building. Note that a brick is able to survive up to 50 cycles without loss for the structure, while aerated concrete blocks survive only 25-35 cycles without any problems. Therefore, if your goal is to build a house for several generations, then you should choose brick as a building material. Or it is reliable to insulate the walls of aerated concrete from the outside, which again will require additional investments in construction.
Block masonry strength
Even a novice master understands and knows that the strength of porous aerated concrete blocks is much lower than that of brick ones. So, brickwork has a strength of 50-150 kg / cm2, and the strength for foam concrete is only 5-20 kg / cm2. That is why building high buildings from concrete blocks is prohibited by the SNiP regulations. Such a building material simply cannot withstand the load of the walls of a house above two or three floors during cottage construction, although the regulations say a maximum of 14 floors. A brick house can be built at least 30 floors, this will not affect the strength of the building in any way. By the way, even during construction two-story house from basement, with a wall height of each floor of 2.5 meters and in the presence of slab reinforced concrete floors walls made of aerated concrete most likely will not withstand such a load and will crack. In this case, it is better to choose a brick.
Tip: if you want to save on construction, you can drive the lower floor out of bricks, and the second one out of blocks.
Fire safety of brick and foam concrete
Here, both types of building materials have a high degree of fire safety and comply with building codes and requirements. The same non-combustible will be a house made of both brick and aerated concrete. Both types of blocks can easily withstand a direct flame for 2-2.5 hours.
Shrinkage of building material
An important factor is the percentage of shrinkage of the house after construction. Thus, porous foam concrete tends to shrink within two years after the end of construction by about 0.3 mm / for every meter of height. Such an indicator can lead to the formation of cracks on the walls. Particularly susceptible to shrinkage is foam concrete located in dry and warm places, such as chimneys, etc. Brick does not shrink at all even for for long years house operation.
Mechanical resistance of the material
It is also worth paying attention to the susceptibility of blocks to mechanical stress. Here, brick is a more complex and unyielding material, while aerated concrete is similar to wood (easily cut and sawn). But at the same time, it is worth considering what to mount in foam concrete wall fixings for shelves, cabinets or brackets under household appliances it will be more difficult. In an aerated concrete wall, you will have to additionally arrange fixation. Brick in this regard is much more reliable and convenient.
Environmental friendliness of the material
If you want the walls of the house to breathe and provide microcirculation of air, then both types of building materials are equally good. And clay brick, and porous concrete they pass air equally, preventing rotting of the walls inside and outside the house. At the same time, neither one nor the other type of material evaporates harmful compounds into the air.
Material cost
In order to finally have an idea about the economic component of the construction, it is necessary to check the price of the material. So, in the Moscow region, the prices for brick and aerated concrete will be approximately as follows:
- Ceramic brick - about 80 USD/m3.
- Foam concrete - 45-50 c.u./m3.
That is, given the volume of material in 1m3 and its cost, we can safely say that a box of foam concrete blocks will cost less. But in any case, you will have to additionally clad the house to protect the blocks from water. And in general, to determine which is better - a house made of aerated concrete or brick, you can only fully calculate all the parameters of the construction and the features of the operation of the house in the future. After all, not always good house is an expensive house. You can successfully use new generation building materials, but at the same time competently approach the choice of finishes and construction calculations. Remember building technology do not stand still and once a brick was a newcomer among the materials.
Anyone who wants to build own house I had to make a choice of building materials. Someone recommended buying a brick, someone liked aerated concrete elements, there were those who recommended combining both materials. For the construction of the box, which is better - brick or aerated concrete? To find the correct answer to the question, it is necessary to study the features and characteristic differences of these materials. The fact is that even professional masters do not have a common opinion. Each type has positive and negative points that are recommended to be taken into account.
Before choosing "brick - aerated concrete", consider the characteristics of the first of the materials. It is environmentally friendly, has a sufficient level of strength, can be used for a long period. A brick building will last at least a hundred years. As ceilings on such walls are used reinforced concrete slabs, allowing you to arrange large rooms and build multi-storey buildings.
There are two types of brick material - silicate and ceramic.
The first option is made from sand, lime and water. Production molds filled with raw materials are placed in an autoclave and fired under pressure.
The silicate material produced on the basis of technology is distinguished by its high density, strength and ability to withstand cold and precipitation.
Ceramic brick material made from clay. Firing is carried out in temperature chambers, the strength of the material and resistance to frost depend on this.
Ceramic brick happens:
- private;
- facial.
Characteristics of aerated concrete
Comparison of brick and aerated concrete is possible only if all the features of the blocks are known. Today they have become popular in the construction industry.
For production use:
- quartz sand;
- aluminum powder;
- cement;
- quicklime;
- water.
Some manufacturers, in an effort to increase revenues, mix slag, ash and other industrial waste into the feedstock.
During the manufacturing process, the components are mixed, water is added, and the finished mass is poured into molds. Due to water and aluminum, a reaction occurs, the result of which are numerous pores. The mixture at this time increases in volume, begins to harden. The blanks are cut into blocks and sent to autoclaves for final strength.
The porosity of the structure makes it possible to exceed the brick material by several times in terms of thermal insulation qualities. The blocks are light, so a brick and aerated concrete wall will be the best choice.
Aerated concrete blocks have good soundproofing ability. By its characteristics, the material is similar to wood - it breathes, keeps heat, and is environmentally friendly.
Advantages and disadvantages
For the final choice between brick or aerated concrete, it is recommended to compare their positive and negative qualities.
Silicate brick material is different:
- environmental cleanliness;
- excellent soundproofing properties;
- resistance to low temperature conditions;
- long service life;
- assortment color shades, which allows it to be used as a finishing raw material.
The disadvantage is the low level of resistance to water and high temperature.
The material is not used in the construction of stoves, wells, chimneys, foundations, fireplaces.
The brick ceramic well resists to frosts, protects from extraneous noise. Its advantages include low moisture absorption, high-quality adhesion to plaster and putty layers. The material is durable, resists external influences, has many textures and colors.
It costs a lot. For this reason, the question - which is cheaper, brick or aerated concrete, does not even arise.
When administering facing works the brick used must be from the same batch.
Aerated concrete blocks are environmentally friendly, the ability to retain heat and protect against extraneous noise. The material is durable, does not shrink, and is easy to process.
As minuses, fragility and the ability to absorb water are noted. Blocks are recommended for use in low-rise buildings, as load bearing capacity brick and aerated concrete is significantly different.
To finally decide which is better, aerated concrete or brick for building a house, it is necessary to compare these materials.
Compressive strength index
This parameter will determine the strength of the object under construction and the maximum load that the walls can withstand. For bricks, this value is from 110 to 220 kg per cm2. And aerated concrete can boast only an indicator of 25 - 50. From this it is concluded that the foam block for the construction bearing wall does not fit.
Ability to conduct heat
The thickness of the wall of brick material must be at least fifty centimeters. This will be enough for the thermal insulation to be within the normal range. To increase this parameter, it is allowed to arrange an insulating layer.
Block walls with a similar effect are forty centimeters thick. And if you have to live in regions with cold climatic conditions, then you can easily understand which house is better, made of aerated concrete or brick.
Low temperature resistance
This value is characterized by the ability of a building material to retain its original properties during numerous freeze and thaw cycles and in a state of high humidity.
Brick resists sharp temperature fluctuations up to five dozen cycles, for aerated concrete this figure is 25 - 30 periods. It turns out that in this respect the brick lasts longer.
moisture absorption
This parameter determines the duration of the object's operational period. With significant absorption, water accumulates in the pores, fungus and mold appear. For an aerated concrete block, this figure is 100%, while a brick boasts a value of 6 - 14%. It is possible to reduce the absorption of water by the block by finishing the surface of the walls waterproofing material and plaster mortar.
Construction work of this nature is carried out exclusively in dry weather.
fire resistance
All considered materials belong to the group of non-combustible with the assignment of class A.
Shrinkage
Aerated concrete blocks are subject to this characteristic, from which cracks may appear on the surface of the walls. For a brick wall, this phenomenon is not typical if a solid foundation is prepared.
Weight of a cubic meter of masonry
The mass of the building is the determining parameter in choosing the type and parameters of the foundation. Walls built of brick material are significantly superior in weight to aerated concrete counterparts, so the base for them will be massive.
Brickwork of 1 cubic meter exerts a force equal to 1.2 - 2 tons, for an aerated concrete block this figure is 0.2 - 0.9 tons. It turns out that with the same size building an object made of foam block is lighter brick building six to ten times.
So, which is better, a brick house or aerated concrete? Blocks store heat better, differ in vapor permeability. However, the brick material is distinguished by its compressive strength, it wins by its resistance to water and low temperatures. Therefore, its operating period is much longer.
However, a house made of aerated concrete or brick - the choice is yours. The fact is that the shortcomings of the blocks are removed with a high-quality lining that prevents the process of getting wet. In addition, wet aerated concrete retains heat poorly.
The blocks are large in size, which allows you to build a box quickly, and the geometry of the material is better. Only the seams between the block rows should be made thin to reduce heat loss.
If a house is being built from aerated concrete blocks, then it is recommended to perform reinforcement. For brickwork, this feature is not characteristic.
The conclusion suggests itself that there is no unambiguous solution to the problematic issue related to the choice of material.
Before starting construction, one of the main issues is the choice of a durable, reliable and inexpensive building material, so you need to figure out what is better to choose - brick or aerated concrete. Before making a choice, you need to decide on the parameters of the future building, its size and operating conditions, only after that you can choose a building material that will meet all the requirements, and decide what to choose - aerated concrete or brick.
Modern construction market presented big amount variety of materials used to build various buildings, but it is not always worth believing advertising - it is better to understand their properties and only after that make a choice. Most often, brick or cellular concrete is used for construction, one of the best is aerated concrete. Often the owner of the site is faced with the question of which is better - brick or aerated concrete - and which material to give preference to.
To do right choice, you need to familiarize yourself with the characteristics and features of brick and aerated concrete, only after that you can choose the material that will best meet your requirements.
brick features
This material has been used for construction for a very long time, and over time its characteristics have improved significantly.
Such a building material has high strength, it has a long service life. If we talk about the price, then with the same volume, aerated concrete is cheaper, brick is more expensive. For its manufacture, ordinary clay is used, which is fired. For different kind bricks use different compositions, they have different dispersion, the strength and price of bricks will largely depend on this.
After the clay is mixed with water and dried in special forms, it already holds its shape quite well. Then it is fired, in which the brick acquires the necessary mechanical characteristics. Roasting is a rather complex and lengthy process, during which the temperature changes dynamically, and a strictly set temperature must be maintained in the drying chamber.
For each clay composition, they develop their own firing technology, from the quality of this technological operation the strength and frost resistance of the brick will depend.
Depending on the composition of the mixture that was used for its production, the brick can be silicate or ceramic.
Benefits silicate brick are its high frost resistance and strength, but it has high thermal conductivity and absorbs moisture well, so ceramic bricks are more common.
This type of building material is washed out worse precipitation, it has lower thermal conductivity and higher sound insulation performance. A brick house will be stronger, but it will take more time to build it, since the latter wins when comparing the sizes of brick and aerated concrete.
It should be noted that the strength of brick is higher, so it is used in the construction of multi-storey buildings, while aerated concrete is usually used for the construction of private houses and cottages, this must be taken into account when comparing brick and aerated concrete.
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Features of aerated concrete
A feature of such a material as aerated concrete is its cellular structure, due to which it has excellent thermal conductivity and sound insulation characteristics, and a fairly low weight. Despite its cellular structure, aerated concrete has sufficient strength, it can be used in the construction of buildings up to 3 floors high. If we talk about what material to give preference to in construction high-rise building- aerated concrete or brick, then here you need to choose a brick.
In order to build a house from aerated concrete, foam blocks from the specified material are used. For the manufacture of aerated concrete are used:
- cement;
- lime;
- water;
- sand;
- aluminum powder;
- slag, ash and other production wastes can be added.
If foam blocks are made with the addition of production waste, then this reduces the cost of aerated concrete, but it turns out to be less durable.
Aerated concrete foam blocks are made in an autoclave, their maximum characteristics are obtained. In the autoclave, increased pressure and temperature are created, so the foam blocks acquire a homogeneous macrostructure.
When comparing aerated concrete and brick, it is impossible to give an unambiguous answer about which option will be better. It all depends on what qualities the future building should have.
Both materials have their own disadvantages and advantages, so only you can make a choice in the direction of aerated concrete or brick.
If you will build low-rise building, then it is worth considering the fact that one aerated concrete foam block will correspond to 7-8 bricks, so the work is carried out much faster, less masonry mortar is required.
If we compare aerated concrete and brick, then foam blocks can be used both for structural purposes and for thermal insulation of the house, while the building, which is made of brick, so that it is comfortable in winter time, it is necessary to do additional thermal insulation.
In order to save money on masonry, it is worth giving preference to aerated concrete.
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Material Comparison
One of the main characteristics that must be considered when building a house is its mass. For brick house a more massive and, accordingly, expensive foundation is needed than for the construction of a building if foam blocks are used.
The thermal insulation properties of the house are great importance both in winter and summer time. In order to be comfortable in the house, the thickness of the brick wall should be at least 50 cm, while the thickness of the foam block wall will be only 30-40 cm.
An important indicator of any building material is its frost resistance. It characterizes how well it will retain its properties at high humidity, as well as with repeated freezing and thawing. If for aerated concrete blocks the number of cycles is about 25-35, then for a brick it is 2 times more, therefore brick building has a longer service life.
The main disadvantage of aerated concrete blocks is that they have little strength, therefore they are intended for the construction of buildings with a height of no more than 3 floors, but for the construction of a private house or cottage, this is almost an ideal material.
With increasing water absorption of the material, its service life will decrease. If for aerated concrete this figure is 10%, then for bricks from 6 to 16%.
If we talk about indicators such as environmental friendliness and fire safety, then they will be high for both materials.
Brickwork has an advantage in terms of shrinkage. Over time, shrinkage of the gas silicate sides occurs, as a result of which cracks may appear on the walls. Near dry heat, shrinkage will be more intense, while this does not happen with brick walls.
The advantage of gas silicate blocks is their simpler mechanical restoration, therefore, it is easier to install doors, windows into such walls, to produce Finishing work. However, this must be done carefully, as they are less durable. Brick walls have higher strength, they also have more options for finishing work.
Both considered materials belong to the first class of fire resistance, they can withstand high temperatures for a long time and do not emit harmful substances. The fire resistance limit of these materials is not less than 2.5 hours, while, for example, for wooden house this figure is only 30 minutes.
It is definitely impossible to compare the cost of these materials, since even within the same city it may differ. It is also necessary to take into account the distance to which delivery is required. Generally speaking, the cost of the same volume of these materials for aerated concrete will be approximately 30% less.
Since the volume of blocks is much larger, then construction works will be carried out faster. If it takes from 3 to 6 months to build a medium-sized brick house, then using foam blocks it will take only 1 to 3 months, that is, the work will be done 3 times faster.
In this article under aerated concrete we will understand the type of cellular concrete, which is obtained from a mixture of cement, sand, water and gas-forming additives that form bubbles in concrete, making the density and thermal conductivity of concrete lower.
Brick is a familiar, ceramic building material produced by firing various clay mixtures.
Both ordinary brick and aerated concrete have a number of specific characteristics by which they can be compared. Among them:
- weight;
- compressive strength;
- thermal conductivity;
- frost resistance;
- fire resistance;
- vapor permeability;
- moisture absorption.
Having information about the above indicators, you can already judge whether this material is suitable for you, taking into account the location and purpose of the future building. Therefore, we will describe each parameter in detail below.
Mass of material
The mass of individual fragments forms the mass of the walls, but it should be taken into account when choosing the type of foundation to be laid.
For these reasons brick walls require a more complex, and therefore more expensive foundation (mainly monolithic or tape), but aerated concrete walls are less demanding in this regard.
But, aerated concrete, unlike brick, has very weak bending strength, which means that the shrinkage of the foundation must be very well done.
A good foundation for aerated concrete should not shrink, and frost heaving should not move it. Therefore, great attention should be paid to the drainage of the foundation and backfilling of non-porous fillers (sand and gravel).
Basically, on good soils a shallow foundation with an insulated blind area is suitable, for more difficult soils it is better to conduct soil geology.
In any case, the choice of one or another foundation depends on the severity of the entire building, such as soil, on the depth of freezing and on the level ground water. And the calculation of all this is a complicated matter, which is best left to specialists.
Comparison of aerated concrete and ceramic blocks (video)
Geometry of gas blocks and bricks
Gas blocks are much larger and smoother than bricks, what conclusion can be drawn from this? And here's one: a gas-block box is built much faster. The seams between the gas blocks are about 2 mm, which minimizes heat loss through the seam. Note that each row of the gas block must be leveled with a grater so that the plane is perfect and the seam is uniform, this is very important. The rows of the gas block are leveled with a grater very quickly and simply, so do not be afraid of this.
Also, some rows of aerated concrete need to be reinforced. For more information about the reinforcement of aerated concrete masonry, see our article.
Aerated concrete can be autoclaved and non-autoclaved, we will immediately say that autoclaved aerated concrete is better in all respects, including the geometry of the blocks, but autoclaved is more expensive. For more information about the differences between autoclaved and non-autoclaved aerated concrete, read our article at the link.
to the seams in brickwork there are no such requirements. It is also worth noting that in a house made of aerated concrete, a monolithic reinforced concrete armored belt is required. And as you understand, the armored belt is a complex design that requires a lot of time and money. The time saved on the laying of aerated concrete will be somewhat taken away when installing the armored belt.
As you might guess, this parameter indicates what level of load the material can withstand; calculated in kilograms per 1 cm². The overall strength of the structure significantly depends on the compressive strength.
The higher the walls of the building, the heavier they are, and the load on the blocks (in compression) increases, and the requirements for compressive strength increase. Compressive strength is usually denoted by classes ( B0.5 to B60) and for aerated concrete this indicator can be in the range from B0.5 to B20.
For example, high-quality aerated concrete brand D500 compressive strength class equals B3.5 which corresponds to the load 46 kg/cm².
| Aerated concrete brand | Compressive strength class | Average strength ( kg/cm²) |
| D300 (300 kg/m³) | B0.75 - B1 | 10 - 15 |
| D400 |
B1.5 - B2.5 | 25 -32 |
| D500 | B1.5 - B3.5 | 25 - 46 |
| D600 | B2 - B4 | 30 - 55 |
| D700 | B2 - B5 | 30 - 65 |
| D800 | B3.5 - B7.5 | 46 - 98 |
| D900 | B3.5 - B10 | 46 - 13 |
| D1000 | B7.5 - B12.5 | 98 - 164 |
| D1100 | B10 - B15 | 131 - 196 |
| D1200 | B15-B20 | 196 - 262 |
Brick also has its own marking for strength (from M50 before M300). For example, brand of brick M100 corresponds to the compressive strength class - B7.5 which corresponds to the load 100 kg/cm².
Thermal conductivity
The thermal conductivity coefficient indicates the ability of the material to conduct heat through itself. This indicator means the amount of heat that passes per hour through 1 m³ of material with a unit temperature difference on opposite surfaces. That is, the higher the coefficient, the worse the thermal insulation.
The photograph from the thermal imager shows what the surface temperature is in which areas, than brighter color, the worse the thermal insulation in that area.
Table of thermal conductivity of aerated concrete
Comparative graph of thermal conductivity of bricks and aerated concrete
So, the graph clearly shows the difference in thermal conductivity between various bricks and aerated concrete, for example, the thermal conductivity of D500 aerated concrete is 4-5 times lower than that of red solid brick. But these are all laboratory figures, in fact, in masonry, the difference between the thermal conductivity changes somewhat, and the thermal conductivity will differ not by 4-5 times, but by only three.
The reason for this is the so-called bridges of cold ”, which refers to the layers of mortar between the parts of the masonry.
In the case of aerated concrete blocks, a special adhesive is used for thin joints, which reduces the heat loss of the structure, but still, the actual performance of aerated concrete masonry in terms of thermal conductivity is lower than those presented in the table above.
It should also be noted that the thickness of the seams in aerated concrete masonry should be as small as possible, ideally (1-3 mm). Thick seams in aerated concrete reduce all its thermal advantages to a minimum.
Another factor that worsens thermal insulation is the humidity of the blocks, the higher the humidity, the worse. And aerated concrete is porous and therefore absorbs water well.
According to heat engineering standards, warm brick walls must have a solid thickness (1 m), while for aerated concrete walls a thickness of 0.3-0.5 m is enough. For the coldest regions, aerated concrete masonry with a thickness of as much as 600 mm may be required.
In general, the thicker the walls, the thinner the seams, and the less damp the wall is, the better the heat will be retained inside the room and the more you will save on heating your home.
We repeat that aerated concrete happens different brands starting from D200 and ending D1200. Number in this case shows the density of the material. The higher the density, the stronger the block, but at the same time its thermal insulation properties are worse.
Aerated concrete grades D200-D300 is used as a heat insulator, and blocks grade D400 and above are used as structural blocks for walls.
Currently, the construction of brick walls with a thickness of under 1 m - a rarity, because it is too expensive both in terms of money, and in terms of the amount of time spent, and in terms of labor resources.
Most often, brick walls are erected in one and a half to two bricks with a thickness of 38-50 cm, and a much thicker layer is used for thermal insulation. thermal insulation materials than when laying aerated concrete walls.
Frost resistance
This indicator demonstrates the resistance of the wetted material when exposed to sub-zero temperatures. It shows how well a material can maintain its strength under repeated freezing and thawing.
Frost resistance is denoted by the letter "F", the number indicates the number of cycles that the material must withstand.
As a rule, brick has a much higher frost resistance coefficient than aerated concrete, that is, brick is a more frost-resistant material, and therefore more durable.
moisture absorption
The moisture absorption index indicates the ability of the material to absorb and retain moisture. The absorption of water negatively affects the strength of materials, and the thermal conductivity also increases.
Since aerated concrete blocks are able to absorb 4-5 times more moisture than bricks, the walls of the aerated concrete block must be additionally protected from water ingress, which, of course, is a minus for aerated concrete.
Moisture absorption testing was carried out by placing the blocks in a container of water. A day later, blocks and bricks were taken out and weighed. The difference between the initial and final mass was converted into a percentage.
For example, we took a cube of aerated concrete measuring 10X10 cm, its weight was 592 grams, which corresponds to the D600 brand. after 18 hours of soaking, the weight of the cube was 869 grams. That is, aerated concrete absorbed 277 grams of water, which is 47% of its original mass. Many manufacturers of aerated concrete write that the moisture absorption of their blocks is only 20%, but something is hard to believe in this after such testing.
Fire resistance of aerated concrete and brick
This parameter shows the ability of building materials to resist direct exposure to high temperatures from open flames. The degree of fire resistance depends on how long building construction will be able to stand until cracks appear and collapses occur during a fire.
In this regard, brick and aerated concrete do not have any special differences, since both materials are included in the first class of fire resistance (limit 2.5). Both types of materials are quite good when it comes to resisting fire.
Output
Aerated concrete retains heat better, and it has better vapor permeability than brick. But the brick is several times stronger in compression and fracture. In terms of moisture resistance and frost resistance, brick also wins. It becomes clear that brick is more durable, and a brick house can last much longer.
But many of the shortcomings of aerated concrete will be removed by high-quality facade cladding, which will prevent the gas blocks from getting wet. Moreover, wet aerated concrete retains heat worse.
Aerated concrete blocks have large sizes, as a result of which it is faster to build a box of them, and aerated concrete also has better geometry. But the seams between the blocks of aerated concrete must be very thin (1-3 mm), otherwise there will be large heat losses.
Also, in a house made of aerated concrete, a reinforced concrete armored belt is needed, and in brickwork it is not necessary.
Aerated concrete walls are very afraid of uneven shrinkage of the foundation and can crack. So it is desirable, under aerated concrete, to make a heavy and very high-quality foundation and additionally give it time to infuse so that the main shrinkage passes.
We have compiled a comparative graph of various indicators, in which the higher the column, the better.
In other words, there is no unambiguous solution to the problem of choosing between brick and aerated concrete, since both materials have their own advantages and disadvantages. When choosing, one should start, first of all, from the project of the future construction, since in some cases it will be much more efficient to use aerated concrete, while in others it may be better to use the good old brick.
But in the realities of the twenty-first century, when the price of electricity and other sources of heating is very high, we would choose 400 mm thick aerated concrete with subsequent cladding. This thickness is enough to provide good thermal insulation without using additional heaters.
In the case of brick, when laying 0.4 meters, you need to use about 10-15 cm of additional thermal insulation with foam, mineral wool or other materials. But, the brick is time-tested, and the buildings from it stand for a hundred years or more, this is due to the good frost resistance of the brick and high compressive strength.
