The modern market for building materials pleases consumers with its rich variety. Relatively recently, aerated concrete began to be used in private construction. Blocks made from such raw materials have many positive characteristics for which many buyers choose them. Today we will get to know more closely this practical and popular material, as well as find out what types of aerated concrete blocks can be found on the construction market.
Modern consumers face a huge selection of building materials for any wallet. Especially popular in recent years, block products that are flexible in work. Moreover, from such elements in a short time you can build a full-fledged house with one or two floors.
Reliable and durable dwellings are obtained from aerated concrete, which it is quite possible to build with your own hands, without resorting to the services of specialists.
Aerated concrete means stone of artificial origin, which is made of concrete with a cellular structure. Many consumers believe that aerated concrete blocks are an analogy of foam blocks. In fact, this opinion is not true. Gas blocks are completely different materials. Voids are formed in them during chemical reactions that occur as concrete hardens. Foam blocks acquire a cellular structure due to the foam component added to the solution.
There are several varieties of aerated concrete blocks. You can choose the right product for a variety of purposes. It is worth noting that from gas blocks not only cottages are built or small private buildings. This material can be safely attributed to universal, since it also makes neat arbors, original fences and even such non-standard objects for building materials as garden beds.
Advantages and disadvantages
Houses and cottages built of aerated concrete are found with enviable frequency today. The prevalence of such constructions is due to the fact that gas blocks have quite a lot of positive qualities, for which buyers choose them.
Let's get acquainted with the advantages of this material:
- One of the main advantages of aerated concrete is its optimal density. This parameter can be from 400 to 1200 kg / m3. If in construction work you use high-quality material with a small specific gravity, then it will take you a little time to build this or that object.
- These materials are moisture resistant. Even if they are located in high humidity, their performance from this varies slightly.
- Aerated concrete has another significant advantage, which is especially valuable for building materials - it is fire safety. Gas blocks are not flammable materials. Moreover, they do not support combustion.
- These materials are not afraid of low temperature indicators. Due to this quality, relevant for our country, it is possible to apply to such blocks even if construction work is planned to be carried out in severe climatic conditions.
- Aerated concrete is an unpretentious material that does not have to be regularly lubricated with antiseptic or any other protective compounds. On such blocks, mold or rot does not appear. In addition, they are completely uninteresting in insects and rodents. Not all building materials boast the same characteristics.
- If you made a high-quality installation of aerated concrete blocks, then they will not create at the junctions of cold "bridges", so the house will not be able to leave the heat.
- Aerated concrete is a durable material. Erection made from it can last more than a century.
- These types of blocks are environmentally friendly. They do not contain dangerous and harmful compounds, so you can not worry about the health of households. Experts say that only natural wood can compete with aerated concrete in environmental friendliness.
- Aerated concrete is distinguished by noise insulation properties. Thanks to them, in gas-block dwellings, annoying noise from the street is usually not heard.
- Aerated concrete is also characterized by excellent thermal characteristics (no worse than that of brick). Houses made of this material, in some cases, can not be insulated at all.
- It is impossible not to mention that aerated concrete is a very strong and strong material. If you provide him with quality reinforcement, then you can safely proceed to the construction of buildings with several floors.
- Aerated concrete blocks are “obedient” materials. If necessary, you can cut them or give them a non-standard shape, as evidenced by many reviews of the masters.
- These products are also popular due to their affordable cost.
- In the production of such blocks, a very small amount of cement is spent.
- Aerated concrete blocks have a very modest weight, so it is not difficult to transfer them from place to place, as well as carry out various construction works.
- As mentioned earlier, aerated concrete is a multitasking material from which it is not only possible to build houses, but also other useful objects such as fireplaces and arbors.
- Dwellings or outbuildings made of aerated concrete are built very quickly, since such blocks are large with light weight.
- Aerated concrete has good vapor and air permeability characteristics. Thanks to these features, there is always a natural air circulation in the living room, which forms the most comfortable microclimate of the home.
- Aerated concrete blocks are affordable materials that are manufactured using high-tech equipment. These materials pass strict quality control.
Aerated concrete blocks are not an ideal material. It has its drawbacks.
- The main disadvantage of aerated concrete is its high hygroscopicity.
- For constructions from this material, it is necessary to prepare ideal foundation structures. The slightest mistake can lead to cracks on the block walls, not only on the masonry lines, but also on the blocks themselves.
- Despite the fact that aerated concrete blocks are responsible for the formation of an optimal humidity level, moisture begins to accumulate in their structure over time. As a result, this leads to their destruction.
- As mentioned earlier, the cost of such blocks is quite affordable, but the same foam blocks are still cheaper.
- These materials have thermal insulation characteristics, but they are not high enough. In this matter, gas blocks are ahead of many materials, for example, foam concrete.
- For these materials, you must buy special fasteners.
- Finishing aerated concrete is permissible only with special materials designed specifically for blocks of this type.
- Buildings with more than 5 floors cannot be built from block aerated concrete.
- Aerated concrete blocks need to be transported carefully so as not to damage them - the porous structure makes such materials more fragile.
Aerated concrete blocks are made as follows:
- First, a mixture is prepared consisting of components such as Portland cement, quartz sand, water, lime and a special blowing agent.
- The solution is placed in a special form. It further carries out the expansion of the mixture. As a result of this process, voids form in the concrete structure.
- When the block freezes, it is removed from the mold and cut in accordance with the correct dimensional parameters.
So get aerated concrete blocks of a certain shape.
There are two main ways to make these materials:
To aerated concrete gained high strength characteristics, the blocks are treated with water vapor, and then placed until completely dry in the chambers that are in a special autoclave. So get aerated concrete blocks of the autoclave type. After a similar treatment, they gain more stable strength parameters.
Non-autoclaved aerated concrete is cheaper than the autoclave option. A similar material is made by wetting and drying the material in vivo.
It should be noted that the formation of aerated concrete blocks from a frozen mixture is considered the main difference between aerated concrete and foam concrete known to all. This fact provokes fierce debate among buyers, since the pores with this method of manufacture still remain open.
Nowadays, several types of aerated concrete blocks are produced. They differ from each other in terms of density and strength characteristics.
Let's look at the list of the most common and common varieties of such building materials:
- D350 Blocks with such markings are less common than others. This fact is explained by the fact that these materials are quite fragile. It is recommended to install them only in the role of sealing structures. Their strength level is only 0.7-1.0 MPa.
- D400 Aerated concrete blocks with a similar marking are strong and reliable. The strength parameters of these materials are usually 1-1.5 MPa. The use of these blocks is allowed both as a heat-insulating base, and as openings in buildings with several floors.
- D600 Thus, high-strength varieties of aerated concrete blocks are marked. Their strength parameters are 2.4-2.5 MPa. Due to its operational characteristics, such aerated concrete is often used in the design of buildings with ventilated facades.
Aerated concrete blocks can have a different shape, for example:
- rectangular - these instances are used in the construction of load-bearing and partition walls;
- T-shaped - these blocks are used for the construction of ceilings;
- U-shaped - such materials are commonly used in the design of window and doorways;
In addition, aerated concrete block materials are:
- heat insulating;
- structurally insulating;
Aerated concrete blocks are available in various sizes:
Knowing the dimensional parameters of these materials, one can easily calculate how much they will be needed to carry out certain construction works.
As for the density parameters, it all depends on the particular brand of blocks:
- structural variants marked D1000-D1200 are characterized by a density of 1000-1200 kg / 1 m3;
- structural and heat-insulating parts of the D600-D900 brand are available with a density of 500-900 kg / m3;
- D300-D500 thermal insulation materials have a density parameter from 300 to 500 kg / m3.
It should be noted that blocks of different densities can be distinguished by type.
Parts from aerated concrete are made with various strength classes. This indicator demonstrates how much load this material can withstand. So, for example, a block of strength class B2.5 can be used in the construction of strong load-bearing walls, the height of which can reach 20 m.
There are also materials having such classes, indicating their strength:
Aerated concrete blocks can have a different coefficient of thermal conductivity.
This indicator is indicated as follows:
These parameters indicate the ability of a warmer space to transfer its heat to cold rooms. The higher the coefficient, the more tangible is the thermal return. To determine the material of a suitable coefficient for your home, you should take into account the level of humidity.
Another important parameter of aerated concrete blocks is their frost resistance. It is measured in cycles. For such building materials, designations from 25 to 100 are used. For comparison, you can take a brick, which can have no more than 50 frost resistance cycles.
When choosing such a material, it is important to consider its shrinkage during drying. It should be no more than a mark of 0.5 m / m. If this parameter exceeds the specified mark, then you risk getting noticeable shrinkage cracks on aerated concrete walls. For this reason, experts strongly recommend buying materials that comply with GOST.
As for the weight of m3 aerated concrete blocks, it all depends on their direct labeling:
- D300 - 300 kg;
- D400 - 400 kg;
- D500 - 500 kg;
- D600 - 600 kg;
- D700 - 700 kg;
- D800 - 800 g;
- D1000 - 1000 kg;
- D1100 - 1100 kg;
- D100 - 1200 kg.
How to avoid cracks?
As mentioned earlier, aerated concrete blocks are crack prone materials. These defects can occur for various reasons, but most often the reason is a poorly executed foundation.
To avoid such problems, you should:
- to equip the foundation of the slab or strip type, clearly adhering to the appropriate technology;
- carry out masonry, not forgetting the arrangement of the reinforced belt;
- create ring strapping.
If cracks still appear on the blocks, then do not be scared. This material has the ability to restore. For this, a high-quality gypsum-based mixture is usually used.
Where can i use it?
Aerated concrete is a practical and popular material. It can be used for various purposes.
Not only private residential buildings are built from this material, but also household buildings. Aerated concrete is also suitable for the construction of industrial and office buildings. However, it must be taken into account that it is hardly suitable for buildings with a large number of floors.
Due to its operational characteristics, aerated concrete blocks can be used in the construction of houses even in harsh climates. In addition, this building material can be used as structural, soundproof and heat-insulating substrates. It is used in the construction of various walls. These types of blocks make reliable and strong external and internal walls - they can be single, load-bearing, double or combined.
Aerated concrete blocks are excellent for installing dividing and fire walls. These elements can be filled with steel or concrete frames.
Another area of application of aerated concrete blocks is the reconstruction, as well as the restoration of old structures. For the restoration of buildings that are already many years old, the gas block is suitable because of its low weight.
This building material is often used to soundproof or heat insulate a home. It is suitable for warming both low-rise and high-rise buildings. To insulate the structure, usually use special varieties of aerated concrete, which are small in size.
Aerated concrete is used in the arrangement of staircases, floor slabs and lintels.
Recently, aerated concrete with a cellular structure has often been used in other areas. In this case, we are talking about the construction of basement walls or foundations. However, justification of the use of aerated concrete blocks usually requires additional testing aimed at identifying the reliability and durability of materials.
How to calculate the quantity?
Before you go shopping for aerated concrete blocks, you need to calculate how much you need them for. This is necessary so as not to buy too much excess material or to procure them in insufficient quantities.
To carry out the required calculations, use the following formula: (LxH-Spr) x1.05xB = V, in which:
- L is a general parameter of the length of gas-block walls;
- H is the average height of the walls of aerated concrete;
- Sпp - designation of the total area of door and window openings;
- 1.05 is a coefficient taking into account a margin of 5% for trimming;
- B is the designation of the thickness parameter of gas blocks;
- V is the volume of the required amount of aerated concrete.
If you rely on the above formula, you can make an understandable table for calculating the number of blocks in a cube.
Dimensions of gas blocks, mm
pieces in a cube
600 × 200 × 300
600 × 250 × 50
600 × 250 × 75
600 × 250 × 100
600 × 250 × 150
600 × 250 × 200
600 × 250 × 250
600 × 250 × 300
600 × 250 × 375
600 × 250 × 400
600 × 250 × 500
But it must be borne in mind that such calculations give only approximate results, which are rather advisory in nature. Today on the websites of various manufacturers you can find convenient online calculators, with the help of which you can easily and quickly make all the required calculations.
How to put?
If at least a month has passed after pouring the foundation foundation, you should do its waterproofing. Carrying out these works is very important, since concrete does not tolerate contact with dampness and moisture.
The starting row of blocks must be laid out using a concrete mixture as a binder component. Keep in mind that the first laid parts will act as the basis for the future wall, so the materials should be installed as evenly and correctly as possible.
If you made mistakes during the installation of the first row, then over time such a block masonry can crack due to internal tension.
It is necessary to level the starting masonry using a special building level and a rubber hammer. Do not forget that the first block row must be reinforced. Subsequently, the bar should be installed every 4 rows.
All the following rows must be laid using a special adhesive solution. Thanks to this technique, the joints are made as thin as possible, due to which the finished wall will have more effective thermal qualities.
In order for the wall to turn out to be as even and neat as possible, it is necessary to use such a detail as a mooring cord. After installation, the upper part of all rows should be treated with a special hand grater (or other similar tool) in order to provide materials with higher adhesion properties.
The laying of aerated concrete blocks is being completed with the arrangement of a reinforced belt. To do this, in the upper part on the finished wall is fixed formwork, assembled from boards. Fittings are laid in it.
After that, concrete form should be poured into the formwork. Its proportions should be as follows: sand - 3 parts, cement - 1. Since the thermal conductivity of concrete is higher than that of aerated concrete blocks, this belt can not only strengthen the walls, but also cause heat loss in the interior of the premises. Because of this, it will need to be additionally insulated.
At present, many manufacturers selling aerated concrete blocks supply ready-made rigid belts to the market. They are elongated blocks with a porous structure and a groove in the middle part into which concrete mortar must be poured.
We must not forget about the reinforcement of block masonry. To carry out these works, you will need not only the adhesive composition, but also reinforcement bars and wall chasers (it will be needed when working with window and doorways of the building).
Having completed the laying of aerated concrete blocks, they should be leveled. To do this, use a planer or a special grater.
Tips & Tricks
When laying aerated concrete blocks, it must be taken into account that the length parameter of horizontal joints should be approximately 2-8 mm. If we are talking about vertical seams, then their size should not exceed the mark of 3 mm. If excess mortar appears from the seams, then they do not need to be overwritten - these elements must be removed with a trowel.
Carrying out do-it-yourself work on laying aerated concrete blocks, it is recommended to use home-made scaffolding. It will be much easier to work with them. Do not forget that the quality of the entire wall will depend on the laying of the starting block series. That is why it is so important to use the building level at the very beginning. If you notice certain inaccuracies, then you need to eliminate them as soon as possible, and only then proceed with the installation of the next row.
If you work with aerated concrete blocks, then you should use only special fasteners. Simple self-tapping screws for such designs simply will not work - they will not be firmly and firmly held in blocks.
Please note that if such parts as gripping handles are present in the blocks, then when they are installed, the consumption of adhesive can increase significantly. The reason for this is that the technology of laying aerated concrete provides for the filling of absolutely all cavities in the course of work.
Carefully transport aerated concrete blocks so as not to damage their surface. It is recommended to cover this material with plastic wrap, which will protect them from negative external factors. If during the installation of window or doorways you did not manage to get into the length of an entire aerated concrete block, then you can take a hacksaw or saw and cut off an extra part of the part. This work does not take much time and effort, since aerated concrete is a malleable material.
If you intend to use aerated concrete for the construction of a private house, then you need to be as responsible as possible about choosing a reliable and strong foundation. This is due to the fact that this material does not withstand the movements of the base. Because of this, the type of foundation should be selected based on the characteristics of the soil and the characteristics of the gas block itself.
Experts do not advise laying aerated concrete blocks, starting from two angles towards each other. As a result of such actions, it will be problematic for you to dress the rows and adjust the finish element to the required size. Before you buy aerated concrete blocks, you need to carefully inspect them. The materials should not be the slightest damage, chips or cracks. If you notice those, then it is better to refuse the purchase.
Do not look for too cheap material. An unexpectedly low price may indicate poor block quality.
In the next video, you will find the laying of aerated concrete blocks.