Which foundation is better for a house made of aerated concrete? Criterias of choice

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Foundation for a house made of aerated concrete

It is not for nothing that professional and amateur builders love aerated concrete. It is lightweight, quite durable, does not require special operating conditions and is relatively cheap.

Its main advantage is its flexibility in processing. In addition, aerated concrete provides good insulation against noise and heat loss.

However, compared to wood, brick or standard concrete, aerated concrete is quite fragile. Therefore, before starting construction, the question involuntarily arises: “Which foundation is better for a house made of aerated concrete?”

Foundation for an aerated concrete house.

Any building will be more durable if you carefully consider the construction of its foundation. The construction of a foundation intended for a residential building should be taken even more seriously than the construction of floors and walls.

Foundation depth for a one-story aerated concrete house.

Diagram of a foundation assembly for a house made of gas silicate blocks.

Therefore, those who are planning to build a house from aerated concrete should work hard on choosing a base.

For a building made of aerated concrete blocks, the foundation will cost slightly less than the foundation for a brick building.

What determines the choice of foundation.

The type of foundation is influenced by several factors:

• features of the site in geological terms (bearing capacity of the soil, heaving, groundwater level);
• expected load on the floors, walls and roof of the house;
• the terrain where construction is planned;
• temporary load (interior items and furniture in the house).

Taking into account the geological features of the site, you can choose the right foundation for aerated concrete construction. So, for example, for heaving soil, a good option would be a variety such as shallow-depth strip, using bored piles and a monolithic grillage. The choice should be determined as follows: the foundation for a one-story house must have good strength and provide the structure with the necessary rigidity.

Some builders believe that aerated concrete is a rather fragile material, despite its fairly high performance qualities. Even with a slight deformation of the base, cracks can spread throughout the entire structure of the building.

Types of foundations.

Foundation for a one-story house made of aerated concrete.
Scheme of a shallow strip foundation.

Basically, foundations for houses made of aerated concrete blocks are made of reinforced concrete. The base for a one-story house can be chosen as follows:

• recessed tape;
• monolithic slab;
• shallow belt (used for heaving soils);
• bored pile with reinforced concrete grillage;
• Shallow-buried strip strip.

The most popular of these types can be called a shallow strip foundation. If the geological conditions are not difficult, the house structure will be provided with sufficient stability. The design of shallow foundations is as follows. The base strips under all walls should be combined into one system, which is a frame with a horizontal arrangement, which will help redistribute uneven deformations of the foundation. A slight deformation is acceptable if it is much less than the limit.

The nuances of creating a strip foundation

Depending on the type of soil and its properties, a special foundation is prepared for the foundation. It can be sand, crushed stone and even concrete.

It allows you to obtain a more uniform surface with the same strength parameters. On such a cushion, the foundation will not experience stress overloads from the weight of the house and ground movement.

Preparing the foundation

So:

• Sand pillow. Thickness 20-30 cm. Made from construction sand of large fractions. The advantage is low price and simple device. Disadvantage: in the presence of groundwater, it requires the installation of a drainage system. In addition, the sand bed is not intended for heavy buildings. Can only be used for one-story houses.
• Crushed stone pillow. Thickness is from 20 to 25 cm. The size of the fractions is 20-40 mm. It is more durable and suitable for multi-story construction. Before laying a layer of crushed stone, it is necessary to lay a tightly compacted 10-centimeter cushion of coarse sand on the ground. Maximum reliability of the foundation can be ensured by a cushion whose width exceeds the width of the concrete strip by 0.3-0.4 meters. It is used for the highest quality compaction of the sand cushion located below. First, sand is laid, then a layer of crushed stone (as an option, crushed stone is mixed with sand), and compaction is performed. Also, instead of crushed stone, AGS (ready-made sand and gravel mixture) can be used.
• Another option for weak and important soils is concrete footing, or concrete preparation. It is made in the form of a 5-centimeter layer of lean concrete. Reinforcement is not applied. Its main task is to provide sufficient rigidity to the base and protect the horizontal waterproofing layer from damage.
• Concrete pad. Unlike the two types of foundation cushions described above, this option can be used on any type of soil, and for a house of any weight and number of floors. Before laying it, a rough layer of compacted crushed stone 10 cm thick is created. Then formwork is created, the upper edge of which will serve as the level of the base of the future foundation. The same rules apply to the construction of a concrete pad as to the foundation, that is, for reinforcement, compaction, etc. When constructing a foundation on foundation blocks (FBS) on a heaving type of soil, special support plates (FL) must be used as a cushion.

Structure of strip foundation

Making reinforcement

After the formwork is made, you can begin to create a reinforcing frame. A strip foundation for a house made of aerated concrete (see photo) requires full reinforcement.

To do this, you need to use a metal rod with a cross-section of at least 10 mm. The frame must be mounted in such a way that the reinforcement in the volume of concrete does not reach the edges, bottom and top of the foundation by 5-10 cm.

Reinforcement of the foundation for a house made of aerated concrete

It is best to fasten frame elements by welding, although in some cases they are simply twisted with steel or copper wire. Welding creates a more rigid and reliable structure, which is very important for a house made of aerated concrete blocks.

Should I order concrete or make it myself?

After everything is ready, you need to decide how the formwork will be poured. You can make the foundation yourself if you have all the conditions and equipment for this. The pouring process does not have to be continuous. You can arrange several hour breaks.

By the way, the instructions in the video in this article indicate what and how to choose, and what difficulties await those who are planning to pour the foundation themselves.

Pouring strip foundation

Also, do not forget that when looking for an answer to the question of what kind of foundation is needed for a house made of aerated concrete, you should not only select its correct type and design, but also the brand of concrete to be poured. Therefore, the easiest way is to order ready-made concrete from a company that produces it. Fortunately, the price of this issue today is not so high.

Note! Before starting to lay the blocks, do not forget to perform high-quality horizontal waterproofing. After all, aerated blocks are very hygroscopic and can very quickly absorb moisture from the concrete mass. To do this, you can apply mastic or a special mixture to the top layer of the foundation, and lay two layers of roofing material or fiberglass on it.

Do-it-yourself waterproofing of a strip foundation

Concrete grade

When ordering concrete from a manufacturer, you may not even know about the selection of concrete grade. However, when making it yourself, you need to have an idea of ​​what grade of concrete should be for a house made of aerated blocks.

According to SNiP 2.03.01-84, the strength of concrete structures is determined by the class designated by the Latin letter “B” and the numbers following it, and is measured in megapascals. However, in practice, the GOST nomenclature is more often used.

This is the well-known marking of concrete, for example, M200 concrete. The higher the grade of concrete, the higher its quality and the properties of the product that depend on it (strength, water and frost resistance, etc.). In private housing construction, as a rule, concrete grades -300-500 are produced or ordered.

Concrete preparation table

Types of formwork

Homemade formwork for strip foundations

In private housing construction, two types of formwork are used - removable and non-removable. The first are made from suitable available materials - boards, plywood, the second are ready-made industrial blocks based on polystyrene foam with internal reinforcement, or concrete blocks with through vertical voids for installing reinforcing bars and pouring concrete.

The main advantage of permanent formwork is simple installation and good thermal insulation of the foundation. In addition, there is no need to waste time dismantling the formwork, and a strip foundation for a house made of aerated concrete will be erected much faster.

Monolithic foundation.

Aerated concrete is a very lightweight material, making installation quick and simple. The monolithic base has increased resistance to loads, so the deformation will not be very pronounced. This type of base is unique - it can be used on any type of soil. It is able to withstand the harshest climate conditions, even if the soil moves, it will not create significant distortions. To build a house from aerated concrete blocks, the foundation must be built with a slab thickness of 40 cm - of which 10 cm is underground, 30 cm above the surface. It is this thickness that will be optimal for long-term operation.

Scheme of a monolithic foundation.

A monolithic foundation should be made only of high strength concrete. To perform reinforcement, you need to choose rods 12-14 mm. A monolithic foundation on a sand bed is good in quality - it can withstand temperature fluctuations and soil movements. The slab variety is considered very convenient - it ensures uniform shrinkage deformation, which is minimized. For areas with heaving soil, this option is ideal.

A slab monolithic foundation can completely absorb seasonal soil deformation and evenly distribute pressure on the ground. A reinforced slab is installed under the entire area of ​​the house, and when the ground vibrates, it can move like a monolith, preventing uneven deformations from occurring in different parts of the building. Thanks to the longitudinal reinforcement, additional protection against cracks in the walls is obtained.

The sequence of calculating the thickness of the future slab.

The initial data includes: all weight loads, including snow loads, specific pressure on the ground for a given type of foundation (reference value, depends on the type of soil), construction area. The weight of the monolithic slab itself is ignored by placing it on a sand bed. The main stages of calculation are:

• Analysis of soil and determination of optimal specific pressure on the foundation.
• Calculation of the mass of the building. The weight of walls (including finishing and insulation), floors, roof structures, furniture, and snow on the roof in winter is summed up.
• Determining the specific load on the ground by dividing the weight of the house by the area and comparing it with the standard value. The resulting difference is multiplied by the dimensions of the slab foundation, the final number corresponds to its required mass.
• Calculation of the optimal volume (dividing the previous value by the density of concrete) and thickness of the monolith.
• Rounding to the nearest multiple of 5 (no matter which way).
• Recalculate the mass of the monolithic foundation and compare it with the recommended one, the discrepancy should not exceed ±25%.

Thickness of the foundation slab for a two-story aerated concrete cottage.
The next step is to determine the optimal depth and thickness of the cushion of crushed stone and sand; these factors directly depend on the type of soil. The minimum trench height is 60 cm, but such laying is only permissible on stable soils. In all other cases, the slab foundation is placed 60 cm below the freezing level. The thickness of the backfill depends on the weight of the building, the minimum is:

• For a garage - 25 cm.
• Light panel structures – 15 cm.
• The foundation for a house made of timber is 25-30 cm.
• For a building made of brick and concrete - 50 cm (of which 20 is crushed stone, 30 is sand).

This layer ensures uniform distribution of the weight load; on difficult soils it is increased by at least 5 cm.

Columnar foundation.

Another popular option is a columnar foundation with a grillage made of reinforced concrete. Depending on the size of the house, the diameter and number of pillars are calculated. After this, their location on the territory is marked and pouring is carried out.

Foundation for a one-story house made of aerated concrete.

Scheme of a columnar foundation.

The next step is to make the formwork for the grillage. All pillars are connected into a single structure using a reinforced concrete belt.

Based on the dimensions of the future structure made of aerated blocks, the depth and width of the base are calculated. Of course, with such a choice there is no question of a basement. But such construction is not only very simple, but also cheap, and therefore attracts a fairly large number of supporters. However, no less preliminary calculations will be needed here than when choosing a strip foundation.

Pile-grillage foundation.

If we compare the types of foundations in terms of price-quality ratio, the best solution for a house made of aerated concrete blocks can be called a monolithic pile-grillage foundation. It is quite simple in design, economical, and quite reliable in operation.

You can also use a pile-slab foundation as a foundation for an aerated concrete structure. Asbestos-cement pipes are used as piles. They are installed at a depth of 2-2.5 m, the reinforcement must be tied in advance. To form a single structure, everything is poured with concrete. This approach can most often be found when building country houses.

Is it possible to build a house from aerated concrete on a strip foundation? To do this, you will need to carry out certain calculations in advance. Improper laying of such a foundation leads to certain forces or deformations that can destroy or damage the walls of the house. Laying a strip foundation to the depth of soil freezing involves the action of pushing forces on the sides of the strip. This does not pose a danger for a heavy wall - there the heaving force is balanced by the weight of the building, but for light walls it is quite dangerous.

Therefore, for an aerated concrete one-story house, it is best to choose a shallow shallow foundation on a sand cushion. The sand must be of large fractions, well compacted. In some way, this represents the replacement of heaving soil with non-heaving soil, so pressure on the foundation strip from below is eliminated.

Selection of foundation materials

To make a monolithic reinforced concrete strip foundation for a house, concrete and reinforcement are needed. According to calculations, the load on the tape was only 3.23 kg/sq.cm. Any concrete can withstand such a load. But, taking into account the proximity of groundwater, I designated the concrete grade structurally - M300. It took about 22 cubic meters. meters.

A huge margin of safety might not be justified for a house made of timber or logs. But for aerated concrete, a rigid strip structure will be the right solution. Reinforcement of the strip foundation is carried out along the top and bottom of the strip, since in these cross-sectional zones the greatest stresses arise when the structure bends due to uneven settlement.

As working loaded reinforcement, I used three hot-rolled A-III rods with a diameter of 16 mm. Transverse reinforcement of the tape was carried out with composite reinforcement with a diameter of 8 mm.

Transverse reinforcement is necessary to ensure the stability of the foundation wall, but with the loads that arise from my house, this task is irrelevant. The main function of the vertical rods in my design is to connect the concreting tiers together.

Which foundation to choose for a house made of aerated concrete?

A building made of aerated concrete blocks is lightweight compared to a house made of other materials. Therefore, you can save a lot on the construction of its base. However, it must be taken into account that the foundation for a house made of aerated concrete must be calculated correctly. The material has many advantages, but its disadvantage is the rigidity of the constructed wall. If the base sags, the facade will crack.

Strip foundation for a one-story house made of aerated concrete.

What foundation is best to build for an aerated concrete house?

The type of foundation is determined based on soil analysis and structural parameters. 1-3-storey houses are built from aerated blocks. Low-rise buildings allow you to choose a cost-effective option. The most suitable types of foundations are:

Of the listed options, the most expensive will be a strip and monolithic base. They require a large consumption of reinforcement and concrete, which increases both the cost and labor costs. It is advisable to install a strip or monolithic foundation for a small house.

However, even in this case, the costs are not justified, since, for example, a column-and-strip foundation is erected with less time and money. Thus, you can refuse to install a strip or slab base due to economic infeasibility.

There are conditions when a strip foundation is the only right choice for a house made of aerated blocks. For example, when the site has soils with a significant shift (sandy heaving) and/or a shallow foundation is needed (from 0.6 m).

The foundation for a one-story house is made of aerated concrete.

Pros and cons of the foundation

Aerated concrete is lightweight due to its porous structure , where moisture easily penetrates, destroying the structural bonds between the particles of the material. When water droplets freeze during the cold season, they expand in volume, which leads to the formation of cracks. First of all, moisture enters the walls of the house from the soil, so experts recommend raising the basement floor above ground level.

In this case, the main advantage of a pile foundation with an overhanging grillage is expressed - insulation of the structure from contact with loose and waterlogged soil. In this case, the piles provide the necessary stability and rigidity, and the grillage is responsible for the uniform distribution of loads on the load-bearing layer of the earth.

For a pile-grillage foundation, which is applicable for aerated concrete houses, the following advantages include:

• the possibility of construction in areas with difficult terrain;
• relatively low construction costs;
• durability of the structure due to the connected contour, etc.

The disadvantages of the technology include:

• complexity of engineering calculations;
• the need for high-quality foundation waterproofing;
• labor intensity and high costs of work on the construction of underground premises.

Monolithic design.

On complex soils, when there is a close approach to the groundwater surface, the choice is a monolithic concrete slab. Plates are divided into 2 subtypes:

• with stiffening ribs;
• without stiffeners.

The absence of stiffeners sharply reduces the strength of the slab, so this option is only suitable for a small building, and not for a residential building or cottage. For example, for a barn. For a house made of aerated concrete blocks, the best option on difficult soils is a shallow monolithic slab with reinforcement ribs made of reinforcement. It is distinguished by the following qualities:

• high load-bearing capacity;
• integrity during soil freezing;
• high resistance to deformation during soil shifts.

The listed parameters allow the construction of 2-3-story buildings made of aerated concrete on a monolithic foundation. This is also possible on sandy soil without heaving. It should be said that a higher number of storeys is unacceptable when building from this material.

Disadvantages of a monolithic base:

1. It is impossible to make a basement, since a solid reinforced concrete pad lies under the entire area of ​​the building.
2. High cost due to high costs of reinforcement and concrete mortar.

A profitable alternative is piles and pillars.

Pile and columnar foundations are characterized by economical consumption of materials, quick construction, and the ability to build on difficult soils. Both piles and pillars are installed pointwise along the perimeter of the future structure. The pillars are placed in pre-prepared holes in the ground.

They are connected from above by a grillage - a monolithic, reinforced concrete, horizontal frame. It is the grillage that combines these elements into a single structure and evenly distributes the load of the house on them. Actually, the building is erected on the grillage.

For construction on waterlogged, weak, frozen or heaving soils, choose a special type of piles - screw piles. They are also the best option for building low-rise buildings on highly heaving sandy soil. Such a foundation does not even require leveling the site. For a small building, screw piles can be installed with your own hands without the use of heavy special equipment.

Advantages of pile and columnar foundations:

• the possibility of installation in any season of the year (tubular piles are used in winter);
• reduce and more evenly distribute the settlement of the house;
• the closed contour of the grillage eliminates weak stability.

Thus, if you are building a house from aerated concrete and have difficult soils on your site, opt for a pile or columnar foundation.

What kind of foundation for a one-story house made of aerated concrete.

Features of the structure of pillars.

The pillars have a rectangular or round shape. They are made of concrete and reinforced with a reinforcement cage. For this type of base, a grillage is also made of reinforced concrete. To construct it, the solution is poured into the formwork, inside which the frame rods are installed.

The grillage is located at the height specified by the project, visually reminiscent of the foundation strip. It should be noted that the columnar strip foundation is most popular in the construction of houses made of aerated concrete.

Pile foundation

A pile foundation, if you choose special piles for this, can be installed literally in one day. It will take a few more days for the concrete to set firmly. A pile foundation has several key advantages:

• When purchasing modern piles for installation, you will not need to rent or use special equipment, but the initial costs increase slightly.
• Seismological resistance, which is ideal for regions with increased seismic activity. It is also recommended to use only this foundation option if construction is planned on difficult rocky soils with an abundance of groundwater.
• High resistance to freezing and various atmospheric influences. It should be noted that piles purchased on the secondary market must be additionally treated with special compounds in order to improve the characteristics in question, because over the years of operation they could decrease.
• Access to construction, regardless of the time of year. When you need to work with concrete, you usually choose autumn or spring, since at this time optimal conditions are created for the complete drying of concrete mixtures. But the pile foundation can be prepared in the winter so that in the spring you can start building the house itself.

Unfortunately, with such a foundation it will not be possible to build a basement or arrange a communications and utility network node on the lower floor.

What blocks can I take?

The base can be built from other ready-made blocks, which are called fbs (solid foundation block). They are a parallelepiped with a large weight, for example, 300 kg. In this case, installation is carried out very quickly. However, the base will have technological seams at the joints of the FBS. The device will also require heavy equipment. Such blocks are suitable for arranging a basement or ground floor.

Parameters for strip construction.

When a reinforced strip foundation is being erected, the important design parameters are:

The depth of the trench for a shallow foundation is 50-70 cm.

The shallow-depth strip base is suitable for buildings without a basement. If a basement is necessary, a deep foundation of this type must be made.

The standard depth of a buried foundation is 1.5 m. The level of soil freezing is taken into account: the trench should be located 0.2 m deeper. The width of the trench is determined by calculation and depends on the expected weight of the entire structure.

A value of 0.4-0.5 m is often taken.

Foundation for a one-story house made of aerated concrete.

Features of the pillar arrangement

The distance between installed pillars should not exceed 2 meters. The pillars can be:

• reinforced concrete;
• made of brick;
• stone.

For an aerated concrete house, shallow burial of the pillars, which is less than the freezing level of the soil, is suitable. Most often, reinforced concrete pillars measuring 150x150 mm are used. Before installing the pillars, install a cushion that is pre-reinforced with mesh. The pillar is also reinforced with rods marked “K”.

How does the thickness of the walls affect the parameters of the base?

Regardless of the number of storeys of the house, the thickness of its walls is taken into account when calculating. This is especially important for the construction of a tape structure.

The width of the trench should be 10 cm greater than the width of the wall (5 cm on each side, since the wall will be located along the middle). The width of the grillage is determined in the same way.

When constructing the foundation, the bearing capacity of the soil in a given area is taken into account. You can find out this parameter at your nearest design organization. Here are tables of the bearing capacity of various types of soil. You can use them if you know the type of soil at the construction site.

How is the process of pouring concrete mortar carried out?

For concreting, use a self-prepared mixture or a ready-made solution supplied using a concrete pump. Procedure:

1. Fill the formwork with mortar.
2. Distribute the concrete mixture inside the formwork.
3. Compact the concrete surface thoroughly.
4. Plan the surface of the slab.
5. Place plastic wrap on the stove.
6. Moisten the concrete periodically.

Regardless of the thickness of the slab for aerated concrete, the hardening process lasts 4 weeks.

Calculation of the foundation for a one-story house.

For a 1-story building, it is enough to take the minimum calculated values ​​if the numbers are given in a range. For example, if for a shallow foundation it is stipulated that the depth of the foundation for a one-story house is 50-60 cm, take the parameter 50 cm. In this case, this depth includes the installation of a sand cushion.

Thus, trenches dug to a depth of 50 cm are filled as follows (from bottom to top):

• sand cushion 20 cm high;
• formwork made of boards or blocks is installed on the sides;
• the frame made of rods is laid in the formwork (2 layers in 2 rows);
• a gap of 5 cm is left between the reinforcement frame and the formwork walls;
• the intersections of the reinforcement are fastened with wire or clamps, step 30 cm;
• concrete solution is poured.

To pour the solution you need: a concrete mixer, a pump, a concrete pipeline, a concrete vibrator.

Stages of work execution

The most common option for a pile-grillage foundation is a support structure installed on bored piles. To arrange it, you have to perform a certain algorithm of actions.

Preparatory activities

The construction site is cleared of debris and vegetation. Marking is carried out, pegs are installed at the locations of the piles. The length of the diagonals must be checked to ensure equality and accuracy of right angles.

Using special machines or a manual drilling rig, wells are prepared, the lower sections of which are slightly expanded to create a support cushion. A rolled-up roofing material or plastic pipe is inserted into the prepared wells, which sets the shape of the support during concreting.

Reinforcement and pouring concrete mixture

A frame of reinforcing bars is formed on the surface. It is made in the form of a spatial lattice, the length of which is slightly greater than the depth of the well; other parameters allow the base to be easily immersed into the hole.

After installing the reinforcement, a concrete mass is poured, the grade of which starts from M200. It is necessary to remove air from the concrete, for which purpose the solution is bayoneted.

The concrete needs at least four weeks to gain the necessary strength, after which you can proceed to arranging the grillage.

Forming a grillage tape

The strongest grillage is concrete. It is poured into a formwork structure set at the required height from the ground surface. For formwork, wooden panels are used, the inner sides of which are covered with plastic film. To increase rigidity, a frame of metal reinforcing rods is laid into the formwork, which is connected to the ends of the reinforcement protruding from the support pillars.

The concrete solution should be poured at the same time. After four weeks, the base will harden and can be treated with waterproofing material.

For a two-story house, the highest calculated values ​​are taken.

The parameters of foundations for 2- and 3-story buildings made of aerated blocks are more durable. They should be like this:

• sand cushion 30 cm high;
• rods 12-14 mm for the frame inside the formwork;
• the pitch between the frame ligaments at the intersection of the reinforcement is 20 cm.

For a columnar or pile foundation, the dimensions of the pillars (piles) are different: they must be of a larger cross-section than for a 1-story building. This parameter is determined by calculations and entered into the design documentation.

In the case of a monolithic slab, the foundation height is 50 cm and 40 cm for 2-3-story and 1-story houses, respectively.

Pile foundation.

If you decide to build a pile-grillage or pile-screw foundation, you will need to make the correct calculations of the installation depth of the piles and the distance between them. Depth is calculated based on the following indicators:

• the length of the façade walls and the load on them,
• depth of soil freezing in the area.

The piles are located in the following places:

• at the corners of the future house;
• under the intersections of facade walls and partitions;
• under places with increased load on the walls.

The depth of entry into the ground should be 30 cm deeper than the freezing level of the soil. And the distance between the pillars is 1.5-2.5 m (at corners and in places with additional load, take a smaller value, that is, 1.5 m). The height of the grillage is 0.5 m.

Expert advice from builders and reviews from owners

What is worth considering when planning the construction of a pile-grillage foundation:

1. 
   The distance between the grillage and the ground surface should not be minimal.
   Despite the fact that SNiP specifies the only requirement in this regard – from 20 cm, experts advise sticking to the value of 35–45 cm.

   In turn, the greater the height of the grillage itself, the less the risk of destruction of foam concrete from the negative effects of soil moisture.

2. Refusal of a drainage cushion, especially in conditions of moisture-saturated soil and when underground sources are close to each other, will significantly reduce the life of the house. It is advisable to lay sand or sand-crushed stone lining not only at the bottom of wells, but also along the perimeter of the structure.
3. You should not rely on the result of a geological survey for a neighboring area, because the composition of the soil, even within one square meter, can be different. When it is not possible to turn to professionals, you need to dig several holes yourself at a depth of at least 2-3 meters to determine the type of soil and its moisture content.

Before embarking on independent design, experts advise you to study special cases of construction. For example, it would be useful to discuss the choice of the number of support elements among forum participants.

Calculation of pillars.

If a columnar strip foundation is installed, the depth and quantity parameters are used as for the pile option. For the manufacture of monolithic pillars, concrete grades from M150 are used. However, it is suitable for a 1-story building with light façade cladding.

A more reliable solution would be to choose the M200. This brand of concrete is suitable for any type of foundation of a 1-2-story building made of aerated blocks. For a 3-story building, you need to choose M250 concrete for the foundation.

Here are the average parameters most commonly found in construction. Consider the individual dimensions of your building and the recommendations of the design organization.

Features of foundation calculations.

We recommend that you order a project or buy a standard one before building a house. A professional calculation of the foundation is necessary to take into account the parameters of future construction. And they depend on many indicators, even on the material of the house cladding.

For comparison: a house with plastic cladding is only slightly heavier. A building with brick cladding puts a greater load on the foundation. The choice of the type of base and the volume of materials for its construction depend on the total expected weight of the structure.

Additionally: for independent calculations, you can use the information from the following GOSTs: 25485-89, 21520-89, 31359-2007, 31360-2007.

Why do you need to calculate the thickness of a slab foundation?

Thickness of the finished slab foundation for the building
All calculations of slab foundations are always made in strict accordance with GOST and SNiP standards. If it is precisely calculated which design will be optimal for a given building, then it is possible to accurately calculate the required amount of concrete for its construction and the foundation will be very strong, just like the future house.

Before starting calculations, you need to additionally obtain the following data:

1. The general perimeter of the foundation (corresponds to the size of the house, may be slightly larger due to an additional blind area or external waterproofing layer).
2. The total area of ​​the slab, taking into account all protective layers and waterproofing.
3. The area of ​​surfaces that are in direct contact with the ground.
4. Quantity of building materials
5. Calculated loads on the soil due to the sole.

Criteria for choosing a foundation for a building made of aerated blocks.

The choice of foundation is determined by the following factors:

1. Geological position of the construction site: soil saturation with water, groundwater level, foundation strength.
2. The mass of the planned building.
3. Your financial potential.

Most suitable soils: medium coarse. They have excellent strength and are resistant to heaving during frosts.

Loams and hard clays have good strength . But they are less resistant to heaving. Here, during construction, it is necessary to take timely measures to prevent frost heaving.

Construction activities on heaving soils should be carried out on those foundations that are buried below the soil freezing mark. The average value here: 1-2 m.

What kind of foundation is needed for an aerated concrete house? If according to the norm, then it should be at least half a meter higher than the groundwater level . And depending on the position of moisture, you can use a structure that is at least 1.5 m deep. Another option is a shallow structure (70-100 cm). Also, when deciding on the depth of the foundation, it is important to take into account the need for a basement.