Today, the construction of walls for various buildings is carried out from a large number of materials. One of them is aerated concrete, which is beneficial, primarily in thermal conductivity. It becomes possible due to the use of aluminum powder in a conventional mixture of concrete. But the strength of such a material will be somewhat lower. Today we will tell why for the construction of a house, aerated concrete blocks will be an excellent solution.
Pros and cons
To understand whether it is worth building walls from a firefoot in general, it is necessary to analyze which pluses and cons.
So, if we talk about the pluses of aerated concrete, then it is necessary to allocate:
- good ability to retain heat;
- The material is very easy to process even with the help of a hand tool;
- The desired size and rigidity of the masonry can be easily compliance due to the highest accuracy of the geometry;
- A significantly larger size of blocks rather than the brick makes it possible to significantly reduce the timing of the object;
- The material has a small weight, which makes it possible to significantly reduce the load on the foundation of the construction, and therefore extend its life;
- Aerated concrete blocks are a completely fireproof material, which benefits from its analogs;
- Even with the correct implementation of waterproofing and strengthening procedures, the cost of one square meter of the aerated concrete wall will still be lower than that of similar materials.
But as in any building material, aerated concrete has certain disadvantages that do not allow you to call it an ideal solution.
We are talking about such aspects:
- Porous structure of aerated concrete blocks is the cause of light water absorption. That is, when using the material for the construction of walls, it is necessary to very carefully consider the moment of waterproofing.
- It must be borne in mind that the block substance is in baked condition. For this reason, in places where elevated loads are observed, it can start cracking. Because of this, before the start of the construction of the facility, it is necessary to correctly calculate the minimum size of the thickness of the walls of the future buildings. And in places, the most at risk, it is necessary to build masonry by reinforcing.
In general, how can you make sure the material in question has yet more advantages than flaws. But the latter, with the right work on waterproofing and strengthening easily eliminated.
Thanks to not too much weight, if we compare blocks with red or silicate bricks by weight, and fire-resistant, frost resistance, good sound and heat-insulating characteristics, aerated concrete is used to build various elements of constructs of different types, ranging from partitions and carrier parts of residential buildings and ending with elements Country cottages and garages.
If we talk about the types of aerated concrete, then this material is several categories:
- D300 – D500. Such blocks are considered lungs and have a low density coefficient, as well as good thermal conductivity. Usually they are used as insulation.
- D500 – D900. This category of blocks will be significantly stronger. But their mass will be significantly more, and they will spend heat better. Most often, they are used as the main material for the construction of walls.
- D1000 – D1200. Such gas blocks are considered severe by weight. Their density will be the maximum among all existing categories. They are used for the construction of buildings that require the formation of a solid design.
Types of fuel-concrete blocks can also be divided by classes into three groups:
- In 2.0 – such a gas concrete is used to form a bearing wallpaper for buildings whose height is not more than two floors;
- At 2.5 – is used as a material for bearing walls if the height of the structure is not higher than three floors;
- 3.5 – can be used to form a bearing wallpaper for buildings having high-rise in five floors.
The construction of buildings using various cell concrete groups to which aerated concrete is regulated by a hundred per number 501-52-01-2007.
If we talk about the main points on the use of aerated concrete, then it should be noted:
- Restriction of the maximum height of buildings. Of the various categories of cellular concrete, you can create for buildings of the bearing type wall, the height of which is up to twenty meters (five floors). If we talk about the height of the walls of the self-supporting category, then it should not be more than nine floors or thirty meters. Focoblocks are used to create a bearing wallpaper, whose height is not more than three floors or ten meters.
- To create self-supporting walls, you need to use blocks of category in 2.5. If we talk about buildings, where there are more than three floors, and in 2.0, if the buildings have a height of three floors.
- The regulatory document regulates concrete strength depending on the number of floors in the construction. If you need to build an external or inner walls of the 5-storey building, then you need to use blocks with durability at least 3.5, and the type of solution itself should not be worse than M100. If we talk about three-storey buildings, then the class of concrete must be at least 2.5, and the solution – M75. And for the facilities in two floors – B2 and M50.
- This regulatory document also requires calculating the most permissible height of the walls from the specified concrete only after the calculations.
It should be noted that this standard regulates only the strength of concrete, but absolutely does not give any explanations in the issue of thermal insulation of the room. Observe the requirements of regulatory documents should legal entities first and foremost. Individuals can only use them as recommendations or guidelines when building a garage, a country house or any other building.
During construction, it is necessary to take into account that during operation, the humidity of aerated concrete blocks is changed, which increases their thermal conductivity.
Calculation of the thickness of the design
The thickness of the outer aerated walls can be calculated by itself. You should take a regulatory impeller for thermal transmission for a specific area and block heat transfer index.
This figure can be calculated if you multiply these indicators to each other. To ensure comfort, heat transfer resistance should either be equal to or be larger than the number of the nominated index, which is calculated by the addition of the coefficient of the degree-day of the heating period and the ratio of the usual time.
If it is necessary to determine the coefficient of degree-day of the heating period, it can be determined by multiplying degrees for the heating period by number of days for a specific place.
In addition, when the thickness of the gas-concrete wall of the carrier group is determined, the thermal conductive material index is necessarily calculated, which directly depends on the density. What it will be more than its thermal conductivity.
If we talk about cottage construction, there are most often used aerated concrete M500. Such solutions are heat-insulating-structural. M600 models with high thermal conductivity have high strength, which indicates that they will produce a lot of heat from the building.
For thermal insulation, use the option M400. Here, the ratio of pores in general weight will be higher than the indicator of 75 percent. This suggests that the material will keep warm. But its strength will be significantly lower. The best for the creation of aerated concrete outer walls according to the properties of thermal insulation are the brands of aerated concrete D300 and D400. Their thickness is in the range from 20 to 45 centimeters. Despite such indicators, these materials contain a large amount of air pores and a little solution that bears load.
The highest strength, but large wall thickness (from 1 meter or more), needed in order to maintain heat inside the room, will be distinguished by aerated concrete brands D800 and D1000. As a rule, such brands are used in the construction of trading pavilions and public buildings, as well as structures where there is additional insulation and a large load. But the golden middle, from which you can make internal and interior walls, will be the D500-D600 blocks, which is usually used in the construction of cottages, residential buildings, as well as other buildings. They have the best ratio in terms of strength and thermal conductivity.
How to cook glue?
Aerated concrete masonry is made on the adhesive compound, which is created from a dry solution with special characteristics, and consists of sand, cement and various kinds of water reducing, plasticizing and hydrophobic type. The minimum suture thickness must be 2-5 millimeters, but to make masonry on such a mass possible with a suture thickness of 8-10 millimeters. Aerated concrete can be put on the sand-cement mortar with a medium suture horizontally than 12 millimeters and vertical – 10 millimeters.
When placing on the Specialties, it is necessary to take into account that it reduces the resistance of the thermal transmission of wall partitions. It is for this reason that in dry and hot weather the material used during masonry is best pre-wedged with water.
Creating an adhesive solution for the construction of wall partitions from aerated concrete should be started directly before carrying out.
Moreover, cooking should be made clearly according to the instructions:
- First, pour a certain amount of water specified on a pack with a mixture into a bucket made of plastic.
- Now we carefully fade there in the necessary proportion dry solution, constantly stirring. It must be left for 10-15 minutes, and mix again.
- In the process of masonry, it is necessary to stir the mixture several times in order to ensure that its consistency remained at the desired level.
- To carry out the masonry in a cold period of time, it is better to use a glue solution that contains in its composition antiorrosal additives.
How to put?
Put rows from aerated concrete is better for glue. First, it is necessary to pour the cooked solution into the container, and using the Kelma or scoop, carefully smeared it along the entire length of the first row of the wall and align with a special gear spatula. After that, aerated concrete blocks should be put on top of glue. Their horizontal progress should be no more than 5 millimeters. Seams need to be carefully filled with glue so that the blocks keep better. Also observe dressings. Vertical seams should shift no more than 0.4 block heights, or about 9-11 centimeters. Glue that is squeezed during this, you must immediately delete so as not to allow him to grab. Now it remains only to check how much laying was performed exactly and produce straightening, using a rubber hammer.
Help make the construction of walls easier can various kinds of fixtures. We are talking about rail-coaches, which make it possible to designate masonry angles. To use them, you need to install them in a vertical position, put tags that will correspond to the height of the masonry rows. After that, between the friends it is necessary to pull the rope-mooring to put the following row of gaskets was significantly more convenient. Now, focusing on the pupil rope, you can simply align aerated concrete. For this, only you need to knock a little by Cyan until the moment until the glue fell completely.
As a number completes, you should create a reserve block that must be in the last. It should be aware of which it must have the sizes to cut the element of the required length, and losing it with a gluable solution from two sides, after which it is put on the required place.
The method of masonry wall partitions, as well as suture size must be selected depending on the category of walls. For example, single-layer walls can have a thickness of 30-42 centimeters. D300-D500 variants usually apply for their construction. If blocks have accurate dimensions, then it is better to do thin glue seams. In other cases, the heat-insulating type solution with a suture thickness of 1-1.5 cm should be used.
Thickness of two-layer blocks can be from 17.5 to 30 centimeters. For them, a lime-cement or thermal insulation solution is usually used. Aerated concrete groups 600 and 700 can be combined with glue seam. The partition made on this technique is better to insulate with a thin layer of insulating material. The thickness of the insulation in this case should be 9-14 centimeters. But the three-layer walls that are made of this type of concrete will have the same thickness as the two-layer. And the method of erection will be identical. That’s just the thickness of the insulation can be even less. We are talking about 8-13 centimeters.
It should be said that the larger the number of layers has the material, the better there will be sound insulation and noise insulation in such materials. But in general, this is characteristic of all materials.
Cellular type concrete requires great care when placing the first layer, because the strength of the walls will depend on the success of this, as well as the final type of construction. That is why it is necessary to thoroughly align the walls, and the mixture for the seams is applied only with the help of a special collector or a spatula with teeth. If the blocks have profiled grooves on the sides, then during their laying on the vertical seams there is no need to apply a solution or glue. It must be applied solely on a smooth surface, and the slits fill in with a special elastic material with sound-absorbing characteristics.
For example, polyurethane or mini-based foam. Only after the solution is driving, which was used to lay the blocks, you can start making a lobbery for communications. After that, you can start applying putty on partitions to align them, as well as improved sound insulation and vaporizolation properties. Although it should not be used for improving vapor barrier properties, but special types of plaster. Usually we are talking about cement plaster.
From the special mixer released in production conditions, it turns out better by properties and homogeneous solution.
The main components are sand, water and cement. Such a solution is usually done or from dry specials, or simply mixing the aforementioned components. Make it easy, but the quality will be extremely low. With an independent manufacture of a mortar of cement type plaster, special weight is prepared by volume of one piece of cement type M400 or higher and three to five parts of the sand from quartz.
But a good plastering solution on a cement basis can be created only from dry mixtures that are manufactured at the factory.
In such mixtures there are also additives that can:
- adjust the lifetime of the solution;
- Hold moisture in the fresh layer of plaster, not allowing it to move into the material of the wall partition;
- Improve the plasticity and ease of laying;
- Do not allow it to manifest themselves on the surface;
- reinforce the adhesion of plaster and base;
- Improve the strength and resistance of layer plaster to cracks.
Apply such a solution on the panel with a special device. Such formulations and easier to apply. Plasters for the machine method are great and to apply them manually. But in the opposite direction such a rule does not work.
Aerated concrete is an effective material for construction due to its highest thermal insulation properties. They are due to its cellular structure.
In order to fully assess the benefits of the material under consideration, some aspects should be known:
- When the walls are erected, a special adhesive solution is used, stacked on the surface of the aerated concrete block with a thin layer of a few millimeters thick. But the seams should be exactly. If they are more, then the seam will turn into the “Cold Bridge”, and the properties of the aerated concrete in the heat insulation plan will significantly reduce.
- When erected in a cold and temperate climate, it is necessary to warm the aerated concrete walls not only inside, but also outside.
- Must be applied to aerated concrete cement plaster and use materials with the highest vapor insulation properties. It is necessary to protect the material from the constant impact of moisture and protect it from the appearance of cracks. If there are still horizontal cracks, they need to be shuffled and do everything to reduce the effects of steam and moisture.
- Plates from such a material should be thoroughly missed with adhesive solution, in order to avoid the appearance of cold bridges and reduce the properties of thermal insulation of the whole building.
- To get a warm house, it is necessary not only to increase the thickness of the wall to the maximum possible value. You also need to use the right type of aerated concrete. For most climatic zones, it is better to use a D600-type aerated concrete or category B2.5, B3.5 thickness of 300 millimeters. But such a choice is best done, relying on heat engineering and strength characteristics.
In general, it is possible to build aerated concrete walls, although it is necessary to know a number of important criteria to know. But, nevertheless, such material is quite universal, because it can be used both in the house and in the apartment. Yes, and it is quite simple to work with him, so this is an excellent solution for the construction of walls.
How to make a partition from aerated concrete blocks, see the following video.