The foundation for a house made of gas blocks. Foundation for a house made of aerated concrete blocks Foundation for aerated concrete block 1st floor

In terms of the ratio of functionality / construction costs, this type of foundation is preferable to the more well-known analogs - tape or pile. However, in low-rise construction, the slab foundation is mounted much less frequently. The main reason is the poor awareness of private developers about all the advantages, features and specifics of the arrangement of the monolith. The article will fill the knowledge gap and allow you to choose the best option for a reliable support for any structure, combined with reasonable economy.

There are several names (floating, solid) and modifications of such a foundation. It all depends on the option and installation scheme. In construction, slabs are known monolithic, prefabricated, "Swedish", ribbed, box-shaped, with reinforcement (or without it) and a number of others. It makes no sense to consider all engineering solutions. For an individual developer, a monolithic reinforced concrete slab is more interesting, which is the best suited for small private structures. Therefore, attention will be focused on it, especially since the technology of its construction is one of the simplest.

Peculiarities

Advantages:

1. Increased bearing capacity. A monolithic slab creates a slight pressure on the ground due to the uniform distribution of the entire load, regardless of the thickness of the fill. An excellent option for a house made of timber, aerated concrete, even brick.

2. Spatial rigidity. This eliminates the likelihood of subsidence in certain areas (for example, a tape) and the appearance of cracks in concrete, on walls or separated joints.

3. Versatility in application. The slab foundation is suitable for any soils, including those called problematic.

4. Simplified construction technology. The construction of a monolithic slab does not require voluminous earthworks, which significantly saves time.

On a note! This does not apply to the option when the project (scheme) provides for a basement (basement, technological) room. In this case, the cost of a monolithic foundation can reach ⅓ - ½ of the entire construction estimate.

5. Possibility of high-quality insulation. Options - laying under the base of expanded polystyrene, introducing special / additives into the solution.

6. Reduction of concrete consumption. Although this is true only for cases of arrangement of an unburied monolithic slab.

Disadvantages:

Many of them are relative, but it is worth noting them as well.

1. Complexity of calculations. This applies to the thickness of the future slab. If we are talking about a building with a basement, then it is better to choose another base option. First, the cost of construction will rise sharply. Secondly, calculations for a monolithic slab will become significantly more complicated.

2. High costs. Much depends on the specific scheme, but it is indisputable that with such construction, savings are achieved on other materials. If the slab foundation is shallow, of small thickness, it can be impressive.

3. Labor intensity. The question is how well the construction work is organized. For example, the use of "automatic mixer" greatly simplifies the technology of pouring concrete and saves time. The same applies to the accuracy of calculations of the thickness of the monolithic foundation.

4. Certain difficulties with individual projects. First of all, when implementing a scheme with a basement and during construction on relief ground.

Calculating the thickness of the slab

It is pertinent to give only general instructions and recommendations, since much depends on the characteristics of construction - soil characteristics, number of storeys of the house, materials from which it is being built, and a number of other nuances.

Initial data for calculating the thickness of the foundation:

Soil type.
The configuration of underground aquifers.
The level of soil freezing.
The presence of a drainage system on the site and its scheme (if installed).

What is determined:

1. Thickness of concrete reinforcement elements (bar, mesh).

2. The size of the cells of the reinforcement and the interval between its layers in the monolith.

3. Distance of the bar from the upper and lower cut of the foundation.

Advice. If you save on anything, then just not on calculations. In the instructions on thematic sites dedicated to this issue, only a general recommendation is given on the optimal concrete thickness - in the range from 200 to 400 mm. But this does not take into account the specifics of the construction of a monolithic foundation for a specific structure in a specific area.

The difference in this parameter of the foundation for buildings of the same type can be significant. For example, the thickness of the slab for a wooden house varies within fairly large limits and depends precisely on the characteristics of the soil, although this is a relatively light construction of 1-2 floors.

* Dimensions - in "mm".

Bar section - 12.
2 reinforcement levels, the interval between which is 70.
The distance of the reinforcement from the cuts of the concrete monolith is 50 each.

Calculation: 12 x 2 + 70 + 50 x 2 = 194.

Rounded - 20 cm. For example, this is the minimum slab thickness for aerated concrete house. But subject to the construction of a shallow monolithic foundation on good, dense soil. That is why it is advisable to entrust all calculations to a professional.

Construction procedure

1. Marking the territory.

It is made after its complete cleaning in accordance with the construction scheme and in the most acceptable way - the "golden triangle", along the diagonals, etc.

2. Earthwork.

The depth of the pit is determined by the total thickness of the slab foundation and "cushion". For the latter, this parameter is selected within 350 mm. If additional warming of the base with Penoplex is assumed, then the volume of soil removed accordingly increases.

Opinions vary widely regarding the structure of the "pillow". There are recommendations to fill ASG, someone advises to use sand interspersed with rubble. It should be taken into account that the less the bedding absorbs moisture from the soil, the longer the foundation will last. Based on this, it is preferable to pour coarse sand under the monolith, compact its layer, and already on top - gravel, which is also compacted.

On a note! Before arranging the "pillow", the maximum compaction of the soil in the excavation is required. The reliability of the monolithic structure directly depends on this. In addition, it is advisable to line the bottom with geotextiles.

3. Installation of formwork.

If the foundation is shallow, then you can limit yourself to only narrow boards made of boards, which are laid out along the perimeter of the pit and knocked into a single structure. As an option - expanded polystyrene plates as non-removable formwork.

4. Waterproofing.

In this case, it is advisable to use a monolithic canvas. Such seamless moisture protection is much more effective than roll materials, the strips of which still have to be bonded.

5. Thermal insulation layer.

Not necessary, but when laid under the Penoplex monolith, the floors of the 1st floor will be much warmer.

6. Reinforcement.

The first mesh is installed not on waterproofing (insulation), but on special devices called "concrete protection". Their height determines the thickness of its layer from the reinforcement to the bottom cut of the slab. There are various options for such stands on sale, so it is not difficult to choose (or make yourself).

7. Pouring solution.

There is nothing complicated in this operation, if you foresee something in advance.

When choosing concrete, you need to focus not only on its brand (at least 300th), but also on the size of the filler fractions. The larger they are, the more difficult it will subsequently be to compact the solution. And given the small thickness of the slab, this will have to be done manually.
Work cannot be left the next day. The monolith is poured immediately, completely. Therefore, you will need at least 1 assistant, even if the foundation is small in size.

Aerated concrete is a popular material for individual construction. It is strong enough, reliable, easy to install and allows you to plan architectural delights. Aerated concrete cottage is considered a stone structure, and it needs a solid foundation. The question of which foundation would be better for building a house from blocks is very relevant. The recommendations of experts and feedback from practitioners will help to understand this matter.

What you need to consider when choosing

All the time of its existence, mankind has been looking for the most durable and comfortable building materials. Aerated concrete block is an artificial porous stone made from quartz sand, water and gas formers. A low-rise house made of this material is heavier than a wooden one, but lighter than a brick one. When choosing a base for a cottage, several factors should be taken into account:

The approximate weight of the building, floors, roof and future furnishings.
Geological features of the site: heaving of the soil, the level of groundwater, the depth of soil freezing, depending on the climatic zone, plus the bearing capacity of the soil.
The relief of the construction site.

Experts advise several types of proven bases that can withstand the weight of a block building:

slab foundation;
monolithic tape at different depths;
columnar base.

Below we take a closer look at each of these options.

Common mistakes when building a foundation

Usually a person learns from his mistakes, but in the case of a foundation, a tiny error can leave the owner without a new home. The most common mistakes are:

Incorrectly calculated depth and width in the case of erecting a base in the form of a continuous tape. In the reviews, the owners of future houses complain that different builders recommend them different tape sizes. In fact, real professionals calculate the dimensions according to a well-known method, taking into account the resistance of the soil.
Depth of occurrence. It is logical to assume that if an aerated concrete building is lighter than a brick building, then the foundation for it is not built so deep. Error! The depth depends on the water table.
Self-construction without sufficient experience. The authors of the mass of articles and videos with the headings: "Do-it-yourself foundation" talk about the ease of work and offer to do everything yourself. Of course, you can try your hand at a bathhouse or a barn. But any unaccounted for trifle in the construction of a two-story cottage can turn into unpleasant consequences.

Monolithic reinforced concrete slab

Solid slab construction is considered the safest solution for a block building. It has a number of indisputable advantages that visitors to construction forums agree with:

when the soil moves, the slab vibrates with it, protecting the house from deformation;
such a foundation is stable on the most difficult soils and in all climatic zones.

On the reverse side of the medal the following characteristics:

long, laborious filling;
the highest price of all existing types of base structures.

Advice. Under the block structure, the thickness of the foundation must be at least 40 cm, and 10 cm are in the ground, and the above-ground part is 30 cm. It is recommended to use 2 layers of waterproofing and 2 layers of reinforcing mesh with a reinforcing bar thickness of 12 mm.

The construction technology involves the participation of 2-3 people and the use of special equipment:

first, a pit is dug, then a thin concrete slab is poured;
on it - waterproofing and wooden formwork with reinforcement;
concrete is poured into the formwork with a solid slab in layers of 150 mm. At the same time, long temporary breaks between the next filling should not be allowed;
each layer is leveled, then tamped with a bayonet shovel to remove air;
the formwork is removed after the entire mass of concrete has hardened.

This design should be upheld from 3 to 6 months.

Strip foundation for the entire area of the house

Monolithic tape is considered the most economical design. The choice of its deepening depends on the structural features. If you are planning a two-story mansion with a basement or basement, then the tape needs to be deepened by 1-1.5 m. For a one-story house of a small area, a shallow structure is quite enough.

Attention! Work on the installation of the strip structure can only be carried out in the warm season. If it is necessary to fill the foundation in winter, use concrete heated with heat guns, and thoroughly insulate the formwork.

Stages of construction of a shallow foundation:

along the perimeter of the building and under all the ceilings specified in the project, a trench with a depth of 70-80 cm is being dug;
a sand pillow with a depth of 40-50 cm is filled up;
a wooden formwork is hammered together, and reinforcement is fixed in it with a distance between the rods of no more than 30 cm;
the structure is filled with concrete.

The strip base for the building made of aerated concrete is excellent for erecting even on fine and medium-loamy soils.

Column foundation for a building without a basement

The base of the columnar foundation, that is, the pillars, are installed at a level exceeding the depth of soil freezing. It is not recommended to use it on weak, loose and heaving soils and on relief, uneven areas.

Attention! For any foundation design, it is very important to use waterproofing, because aerated concrete perfectly absorbs moisture.

The number of necessary supports for the structure is calculated, depending on the intersections of the partitions of the house. 4 pillars go at corners, then one for each intersection and one (if necessary) at the points with the expected highest load. The maximum distance between the posts is made no more than 2.5 m.

The pillars themselves are made of brick, stone, concrete or reinforced concrete. Some practitioners advise building them extending downward to maximize stability.

The pillars are installed vertically to a depth exceeding the freezing depth. It can be a meter or 1.5 m. The space between the supports is covered with sand, then the pillars are tied with a reinforced concrete belt.

Of the three types of foundations listed, such a structure is considered the cheapest.
When performing any type of foundation in accordance with all the rules and building codes, aerated concrete cottage will be stable, reliable and durable.

Aerated concrete house foundation

When deciding which foundation is best to choose for a house made of aerated concrete, several factors must be taken into account. First of all, the design features are influenced by the properties of the wall material. Foundations for houses built from aerated concrete must take into account some of the distinctive characteristics of this material.

Features of aerated concrete blocks

Here we will consider those characteristics that have a direct impact on the foundation for a house made of aerated concrete. Before choosing a type, consider the following features.

Gas blocks are piece material. Even with the correct choice of the masonry mortar and the observance of the technology for performing the work, they are weakly connected with each other. This factor translates into the fact that the walls of the building are extremely sensitive to various deformations of the base.

If the foundation for a house made of aerated concrete sags or, conversely, rises from the ground, cracks may appear on the walls of the building. Cracks in most cases will be oblique. The opening width and length depend on the scale of the displacement of the building support. To prevent the occurrence of damage, it is required to provide reliable supports that will resist various kinds of displacement. The structure should connect the wall from separate blocks into a single system.

The task of the foundation is to prevent such phenomena

The foundation for aerated concrete is needed less powerful than for a brick house. This is due to the lower density of the material, and, accordingly, the mass. For comparison, the density of gas blocks is from 350 to 700 kg / m3, while a brick wall will have a density of 1800 kg / m3. Blocks with a minimum density cannot be used as structural elements; the material of load-bearing walls has a mass of 500 to 700 kg per cubic meter.

Despite the advantages of blocks in comparison with bricks, it is worth remembering that the material is inferior to wood. Also, the building will be heavier than the frame house. When choosing foundations for houses made of lightweight aerated concrete, this feature must be taken into account.

What types of foundations are used

All foundations, depending on the working conditions, can be divided into four large groups:

columnar;
pile;
tape;
slab.

Variants of the bases used

The first and second in private construction (taking into account the most popular sections) have a relatively low bearing capacity. Such elements work only for compressive loads. It is especially advantageous to make them from concrete, since this material has good compressive strength. Also recently they have become widespread.

The strip foundation takes up mainly compressive loads. When installing on soft soils, slight bending effects may also occur. If the monolithic foundation is made in compliance with the technology, they do not cause problems.

The use of a slab foundation differs in that this design works in bending and punching. Concrete does not resist such influences well. To prevent damage, a mixture of sufficiently high grades is chosen for pouring, and reinforcement is prescribed with special care. Before installing the slab, it is recommended to calculate its strength and rigidity. Only a professional designer or constructor can perform such work.

How to choose the type of foundation

Before choosing which type of support is best to use for a house made of aerated concrete, you must consider the following points:

geological conditions of the construction site, foundation strength, soil water saturation, groundwater level;
the mass of the building (when comparing buildings made of the same material, this characteristic is strongly influenced by the number of storeys);
economic opportunities.

Influence of soil characteristics

Soil moisture and soil type affect the elevation of the support. Soils on the site can be one of the following types:

coarse;
coarse sand;
medium sand;
clay;
loam;
sandy loam;
fine or dusty sand;
bulk soil.

The last two positions have very low strength indicators. It is not recommended to build on such bases (only pile foundations can be an exception). The best option would be to replace the material with medium to coarse sand.

The best soils for construction will be coarse and sandy (medium and large)... Such bases are highly durable and are not prone to frost heaving (one of the main enemies of foundations for aerated concrete houses).

Refractory clays and loams also have good strength characteristics. But all clay soils (clay, loam, sandy loam) can lead to uneven elevation of the building in winter. This phenomenon occurs due to frost heaving. In this case, the outer walls of the building rise more than the inner ones. Cracks appear on the walls of aerated blocks. When building on such bases, it is required to take timely measures to prevent frost heaving.

When building on heaving soils, it is necessary to choose those types of foundations that are buried below the freezing of the soil. The value is determined according to regulatory documents. On average, this value is within 1-2 m.

The foundation for a house made of aerated concrete (its sole) must be at least 50 cm above the groundwater level. Depending on the location of the moisture, you can use a buried structure (it goes into the ground by 1.5 m or more) or (in this case, the laying is taken to be about 70-100 cm). Also, when choosing the depth of the foundations, it is necessary to take into account the need.

Structural features of the building and load on the foundation

To choose which foundation is best for a block house, it is recommended that you familiarize yourself with the table below. The dimensions and thickness of the support part are assigned by calculation.

Soil on the construction site	For a one-story block house	For a two-story block house
Coarse soils, sands, medium and large	To save money in this case, columnar bases or tape bases with a shallow depth of laying are used.	For such buildings, pillars are used. In this case, the strip foundation under the aerated concrete house should have a T-shaped section (increased thickness from below). It is better not to use a rectangular section type due to its low bearing capacity
Clays, loams and sandy loams (most often they are water-saturated)	You can use a pile foundation made of screw supports. They are perfect even with saturated soil. A reliable monolithic grillage is made along the pile heads, which will connect the individual supports into one system. A slab base will also be an excellent option (due to the low load, the thickness of the foundation is used relatively small, about 200 mm)	In this case, the foundation for a house made of aerated concrete is assigned a tape or slab type. In this case, the tape must be laid below freezing or have reliable insulation. To protect the building from moisture, a drainage system, waterproofing and a blind area around the perimeter are designed. The tape can be made from monolith or FBS blocks. The monolithic option is preferable, since the FBS are weakly coupled. By cutting them, you still have to perform a reinforced concrete belt. The thickness of the foundation is assigned depending on the thickness of the walls. If the basement device is not planned, a shallow slab is used. This approach will reduce construction costs
Areas with a high groundwater table (marshland)	As a supporting part, you can use a monolith or FBS tape. In this case, it is necessary to observe the distance between the base of the foundation and the water level of -50 cm.With a very high rise in moisture, a slab or screw piles is used as a foundation	Screw piles have a fairly low bearing capacity. When building a house on two floors in a swamp, it is recommended to use a slab as a foundation

The answer to the question of which foundation is best to apply depends on many factors. None of them can be missed.

When choosing materials for building a future house, you must pay special attention to the foundation on which it will stand. If the base is done correctly, the load-bearing walls will last a long time and will not crack. So, what is the right way to make aerated concrete or gas silicate for a house?

Pros and cons of aerated concrete houses

The gas block has the following positive qualities:

thermal insulation and sound insulation, buildings made of it are energy-saving;
light weight - savings on the foundation, because you do not need to create a powerful foundation and dig it deep into the ground;
the price is cheaper than brick and other old materials.

At the same time, aerated concrete is fragile. When the soil moves, cracks appear and diverge along the entire structure. Therefore, it is important to choose the type of foundation correctly.

MZLF scheme.

How to choose the type of foundation for construction

The main criteria for choosing a future foundation for an aerated concrete house:

The total weight of the structure: frame, furniture, finishing materials, household appliances, roofing material, possible precipitation on the roof;
Heaviness and freezing depth of the soil on which construction will be carried out.

Freezing of soils in Russia.

Types of foundations for a gas block house:

Shallow belt, with a height from the depth mark to the surface of no more than 10-15 centimeters. Ideally holds the structure of the building on highly heaving soil, as well as with an average depth of freezing.
Monolithic- one-piece slab of high quality metal reinforcement and concrete. Suitable for heaving soils of any complexity, you need to make a separate one. Minus - a costly option, up to 1/3 of the cost of the entire structure.
Tape on piles. Placed on particularly unstable soils of medium and strong heaving. Combines tape and pile technology, is complex in execution. The optimal location, the depth of the tape and piles are calculated, a grillage is needed to strengthen the structure. It is recommended to make drainage for the removal of melt and groundwater.

Based on the characteristics, it is better to choose a shallow strip foundation (MZLF) for a house made of aerated concrete. It consists of a sand cushion for leveling soil vibrations and general strengthening, a concrete tape with reinforcement, waterproofing, drainage and insulation.

MZLF device

Device.

To understand how to build a foundation, you need to know what it consists of. The first element is the sand cushion. It neutralizes soil vibrations, strengthens the structure.

The second part is the concrete tape itself, reinforced with reinforcement. Also important components are waterproofing, drainage and insulation.

Construction stages

1. Planning. First of all, the calculation of the total weight of the structure is made, including the useful mass and the box of the aerated concrete building itself. A drawing of the structure is being prepared, soil characteristics are being studied. After that, a diagram of the base is drawn with all corners, load-bearing walls and internal partitions.

2. Land preparation. It all starts with cleaning the area from debris and vegetation. Trees and shrubs are removed along with the root system. If reinforcement with piles and grillages is planned, you need to dig a control hole 1-1.5 meters deep in order to study the soil layer of the soil.

3. Digging a trench. The depth of the ditch will not exceed 15 cm. But you need to take into account approximately the same thickness of the sand cushion. In addition, the tapes should be 15 cm wider than the bearing walls. The bottom of the finished trench must be leveled from the bumps and grooves.

Marking and excavation.

4. Creation of a sand cushion. To do this, you need to take coarse sand, pour it on the bottom of the trench with a layer of 10-15 cm. After that, pour water and tamp it well so that the surface is even. The sand can be reinforced with fine crushed stone, up to 5 cm.

5. Formwork creation. The form is made from flat wooden boards or boards. It can be arranged at different depths. placed directly in a trench or on the surface of the earth.

In the finished structure, it is necessary to calculate and make ventilation holes.

6. Reinforcement. A necessary step to strengthen the tape on heaving soils. It is made from special metal rods or fittings. All elements are connected with a wire; welding cannot be used.

Reinforcement.

7. Drainage. Water drainage is necessary so that underground streams and moisture do not destroy the foundation. It is necessary to make a calculation of the system immediately before pouring the concrete solution, separately from ventilation.

The drainage itself is a drainage system made of pipes covered with an anti-corrosion layer. Submerged in the ground, they remove the accumulated water to the outside. It is worth contacting a specialist to plan drainage.

8. Main tape. It is necessary to prepare and pour concrete in layers. The depth of the bottom layer should not exceed 15 cm. After drying, the second layer is made, then the third, and so on. When everything is filled in, the surface is covered with a film until it is completely hardened.

Pouring concrete.

9. Waterproofing and insulation. Sheets of roofing material are laid out on the base of the tape treated with mastic. When the waterproofing is bonded, you can make thermal insulation. Insulation materials for heaving soil must be selected with the help of a specialist.

Near-foundation construction.

The creation of a shallow foundation for a house made of aerated concrete provides for the calculation of a whole system to protect the foundation from adverse factors. The foundation created in accordance with the technical requirements will be able to neutralize any fluctuations in the soil. It reliably holds the structure of the house, preventing it from collapsing.

As you know, there are such large categories of foundations: strip, slab, columnar and pile. But what is the best foundation for aerated concrete? We find out.

Criteria for choosing a foundation for a gas block structure

The choice of the foundation is due to the following factors:

Geological location of the construction site: soil water saturation, ground water level, foundation strength.
The mass of the conceived building.
Your financial strength.

Most suitable soils: medium coarse. They have excellent strength and resistance to frost heaving.

Good strength near loam and hard clay... But they are less resistant to heaving. Here, during construction, you need to take timely measures to prevent frost heaving.

Construction activities should take place on those foundations that are deepened below the freezing mark. Average value here: 1-2 m.

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

Structural specifics of the building and pressure on the foundation

The following table is suggested here. It reflects the types of soil and suitable foundations for them.

Soil types	Aerated concrete house. One-story.	Aerated concrete house. Double decker.
Soils with coarse debris. Sands of medium and large parameters.	Blocked or shallow tapered.	Columnar or tape with a T-shaped section.
Clays, loams and sandy loams (most often they are water-saturated)	Pile with screw supports.	Ribbon or slab. The tape is located below the ground freezing or is powerfully insulated. Monolithic tape is allowed.
Areas with a high position of groundwater (swampy area)	Monolithic tape or tape from FBS. The distance between the sole of the base and the position of the water is 50 cm. If the moisture rises very high, a slab base or screw piles are used.	Platen

Thus, what kind of foundation is suitable for building from gas blocks? This is a tape and slab option.

Strip foundation. Shallow deepening (MLF)

Its advantages:

Reduction in the volume of earthworks.
High dynamics of construction.
Additional measures unnecessary if the groundwater position is at least 1 meter above the ground.
Laying on conditionally non-porous and non-porous soils.

According to the manufacturing method, it can be monolithic or prefabricated. For a house made of aerated concrete, the first is better suited. It is stronger and more reliable.

By the type of section, MLFs are rectangular and T-like. The former have weak bearing qualities. Therefore, preference is often given to the latter. And MLF in this situation is formed by a ribbon, a pillow with a horizontal arrangement and a vertical component.

Laying level

Before installing the MLF, it is important to study how deeply the soil freezes in your area. It is also useful to rely on the data and the table below:

It is equally important to base the work on the position of groundwater. If they are closer than two meters to the intended sole, it is better to make a buried foundation and arrange drainage technology.

Protection methods

They are essential to extend the life of the MLF. They are as follows:

The tape is insulated along the entire laying height. Material - extruded polystyrene foam.
A warm blind area is made. The material is concrete. The same insulation is laid under it. Thickness: 10-15 cm.
Vertical waterproofing is made. She lies under the insulation. Material - bituminous roll or mastic.
Water is drained from the foundation. Stormwater and drainage are being arranged.
A sand layer of 30-50 cm is made. The type of sand is large or medium.

Stages of MLF creation

They are in many ways similar to the stages of creating a buried tape. They are as follows:

The zone is marked. A trench of the required parameters is being made.
A sandy layer is being built up (see paragraph 4 above). Thoroughly rammed.
The formwork is made of polystyrene.
The structure is reinforced.
The concrete composition is poured. The work goes in one session. Desired concrete: B15-B25.
The concrete is compacted with a vibrator.
The concrete hardens. Care follows.
if necessary, the formwork is removed.
The foundation is being waterproofed.
The foundation is insulated.
Backfilling follows.
A blind area is created.

Disadvantages of tape backing

Impressive spending.
A lot of building materials are needed.
The need for waterproofing each unit.

Slab foundation (PF)

For aerated concrete construction, PF is a more reliable and durable option, especially if it is monolithic. It is suitable for erecting one- and two-story buildings. True, its cost is extremely high - almost a third of the price of the entire building. This is in the case of involving specialists. If you create the stove yourself, you can save money and create a quality foundation (if you follow the right rules).

PF advantages:

Suitability for buildings of different heights (1-2 floors).
Suitable for houses with a basement.
There is no need to lay the logs on the floor.
The result is a powerful base that is resistant to seismic factors.
Minimal risk of water flushing.
Device in areas with difficult ground.

Usually slabs are made flat or ribbed. The second option is the most difficult for independent work. But its functionality is better and it handles building loads better. This is the best option for a two-story house made of aerated concrete.

For it, you first need to create special edges, and then the plate itself. Sand is used to fill the voids between the ribs.

And when your work site has a very difficult ground, and you want to build a medium or small house, then you better arrange a flat PF.

Stages of PF creation:

The soil is being prepared. The working area is leveled. Pours in soil. It is thoroughly rammed with a vibrating tool.
The suitable parameters of the base are calculated (thickness, length and width). The soil is removed to a depth of about 30 cm. It turns out a "container" for future filling.
The bottom of the "tank" is covered with geotextiles. Drainage is done.
The "container" is filled with a mixture of sand and gravel. The surface is watered and rammed thoroughly. It fits on - thick polyethylene. And then - extruded polystyrene foam.
The formwork is being assembled. Material - expanded polystyrene. Wall thickness - up to 25 cm.
... The fewer the reinforcement connections, the stronger the binding will be.
The end ends of the monolithic slab are reinforced.
The plate itself is reinforced. Additional reinforcement is placed on columns, walls and supporting elements.
The slab should be poured. Desired concrete: M350 - M450. Water resistance parameter - minimum W6. Concrete is fed from a mixer. First, the far side of the PF is concreted, then the near edges. We need helpers to work. Someone pours the mixture, someone compresses it with a vibrator.
The concrete sets. After a day, it is thoroughly watered. If the work is going on in the heat, the concrete is covered with thick polyethylene.
It takes 10 days for the concrete to fully harden (if the air outside is +20 C) or for 20 days (the condition of the outside temperature is + 10C)

About the monolithic foundation in the video

Material from ProfiBlok:

Pile foundation (SF)

If the zone for a building made of aerated concrete is a swampy area, a zone near the coast, a slope, a peat bog, then the best option (and the only one) is the Pile Foundation (SF).

Advantages of the Federation Council:

Excavation work is needed only for the hanging grillage.
Powerful performance - 14 days maximum.
No special equipment needed.
A pick-up is needed only for high grillages.
Complete geological analyzes are not required. Pile penetration test will determine the depth. Next, choose piles of suitable length.

Pile grillages are the optimal solution for a one-story attic building.

Cons of the SF: it is necessary to thoroughly connect all the working elements, the slightest miscalculation can lead to the collapse of the SF.

Column foundation (STF)

It should be applied when the groundwater position is 2 m from the columnar foot. Suitable areas: those with rocky, sandy or gravelly soil. For an aerated concrete structure, such a foundation is not very suitable due to its serious disadvantages.

Cons of STF:

Weak spatial rigidity.
Tendency to fall due to lateral soil movement.
The need for a large volume of operations to reduce heaving pulses.
Complete disrepair for a two-story house.

Material calculations

They follow the example of creating a monolithic LF. Basics of calculations: parameters of blocks and the house itself.

Project example

The intended living area of the house is 65 sq.m.
Roof parameters - 124 sq.m.
House parameters: 9 x 8 x 6.3 m.
There is a load-bearing partition, it divides the house into two parts
There are internal partitions. Divide these parts into rooms.
Clay soil. Freezing - 90 cm.
The occurrence of waters is 2 m.

Based on this data, the foundation is set with the following parameters:

about 45 m long,
75 cm tall,
30 cm is the minimum width according to calculations.

Calculation of materials for the sole is reduced to determining the area of the foundation: 0.3 mx 45 m = 13.5 sq. M.

Laying depth: 3/4 of the freezing mark of the ground, but at least 70 cm.

Concrete consumption

The required concrete is M150. The parameter 13.5 cubic meters is used here.This is the result of multiplying 0.3 * (0.25 + 0.75) x 45 = 13.5 m 3.

Specific weight of reinforced concrete - 2500 kg / m3. Full mass of LF and base:

2500 kg / m 3 x 13.5 m 3 = 33 750 kg.

Blocks for external walls have parameters of 60 x 30 x 20 cm, 500 kg / m3 (density). Each block weighs 20 kg.

It takes 660 blocks to create walls 30 cm wide. Calculation: 36 m (the perimeter of the structure) and 6.3 m (its height). The length of the block is 60 cm, the height is 20 cm. For the entire filling of the perimeter, 1890 blocks are required. Calculation: (36 m: 0.6 m) x (6.3 m: 0.2 m) = 60 * 31.5 = 1890.

Taking into account different openings, this value is reduced by almost three times.

The weight of all blocks: 20 x 660 = 13200 kg.

Blocks for internal walls have dimensions of 60 x 20 x 12 cm. Density is 300 kg / cubic meter. Each block weighs 4.35 kg. They need 560 pieces. Weight of all partitions: 4.35 x 560 = 2436 kg. For convenience, this value is rounded up to 2400 kg.

Metal for creating external doors, provided that the standard door dimensions are 2 x 0.8 x 1.6. Weight - 250 kg.

Lumber for work is selected from softwood. Their total volume is 23 cubic meters. After all, the specific gravity of such a breed is 500 kg / cubic meter. Calculation: 500 x 23 = 11500 kg.

Concrete slabs on the basement floor. Type - with voids. Their thickness is 0.22 m. The specific weight is 1.36 t / m3. Area calculation: 9 x 8 = 72 sq.m.

Volume: 72 x 0.22 = 15.84 cubic meters.

Total mass: 15.84 x 1.36 = 21542 kg.

Facing brick. Calculation of the finishing area: (9 + 9 + 8 + 8) x 0.25 = 8.5 m 2.

For 1 m, 51 bricks are obtained. Each brick weighs 2 kg. The formula works: 8.5 m 2 x 51 pcs / m 2 x 2 kg = 867 kg.

Calculation of the composition (if 0.02 cubic meters of composition is consumed per 1 square meter of masonry): 8.5 x 0.02 m 3 = 0.17 m 3.

Mass of the train: 0.17 m 3 * 1.1 t / m 3 = 187 kg.

The whole weight of the finishing: 187 + 867 = 1054 kg.

The whole mass of the building with loads

All calculations are summarized here. And without aerated concrete overlap, it turns out:

33.75 + 13.2 + 2.4 + 0.25 + 11.5 + 21.542 + 1.054 + 0.61 + + 0.25 + 0.504 + 0.096 + 0.65 + 0.25 = 86.056 tons.

Including overlap:

86,056 + 12,116 = 98,172 tons.

Snow load taking into account a flat roof: 124 m 2 * 160 kg / m 3 = 19 840 kg.

Here 160 is the average value of the snow load.

Calculate the payload from furniture and occupants: 6439 × 180 = 11682 kg, rounded up - 11700 kg.

The cumulative value of the load from the entire structure: 88.4 + 18.6 + 11.7 = 118.7 tons.

Calculation of the specific pressure (UP) under the foundation sole: P = 118.7 / 13.47 = 8.81 t / m2 (the entire mass of the house is divided by the area for this sole).

You need to look at the reference materials. According to them, the UD for clay soil = 10 t / m2. The parameter is greater than the obtained value (8.81). This means that all calculations are correct. And the LF for the aerated concrete house is well designed.

Calculations on a slab foundation

Under the same conditions as in work on a monolithic LF, it is necessary to calculate the area of the slab and its thickness. The calculation method is similar to the operations for calculating the LF. In this case, the height of the house is 6.3 m., Then stiffening ribs are required.

The parameters of the reinforcing elements are also important.

So a bar for reinforcement is suitable with a cross section of at least 2 cm. Its level is the second. The interval between the bars is 9 cm. The reinforcement leaves the slab cut by 5 cm. Calculation: 2 x 2 + 9 + 5 x 2 = 23 cm. This is the thickness of the slab for the house in this case.

Strength calculation of the base

Concrete grade - M350. Payment:

118.7 tons: 36 (perimeter) x 0.3 (wall thickness) = 10.9. Rounded 11 mPa

The parameter of this concrete grade is 25 MPa

Calculation of the bearing capacity: the mass of the slab is divided by its entire area... The result obtained is compared with the tabular data of a certain soil in your area. If the indicator is lower, then the calculations are correct.

What foundation is cheaper after all? The most profitable is the design where the least consumption for concrete is. And if according to the calculations (which is unlikely) there will be a slab, then there are no questions - we are preparing the basis for the slab structure.

An overview of all types of foundations in the video

Webinar from Gleb Green.