The best foundation solutions for your home. Which foundation is better than tape or slab

Content:

Construction of any house in mandatory starts with creating a foundation. The strength and reliability of the base guarantees a long service life of the building.

Modern building technologies allow the use of different types of foundations. Piled, tiled, columnar or tape base - each of them has its own pros and cons.

Which foundation is better to choose? What determines the choice? What factors should be considered?

Before choosing one or another type of foundation, it is necessary to weigh a variety of factors. Sometimes you have to do real research. The main factors that will influence the choice of the type of foundation, experts include the following:

• First of all, you need to determine the type of prevailing soil in your area.

It depends on this to a greater extent which foundation is best for the house. For example, if the soil is saturated with water, then it is better to stop at the pile option;

• The next important parameter is the depth of soil freezing. As a rule, the lower level of the foundation should be located 20-30 centimeters below this indicator. But modern technologies allow you to make a shallow base. In this case, it is not necessary to go below the freezing level.

For example, it is possible to upload strip foundation with a tapered profile, the upper part will be narrower than the lower one;

• Another important factor is the depth of the groundwater... The closer they are to the surface, the more resistant the foundation should be to ground movements. In addition, it is necessary to use more moisture resistant materials during construction.
• And of course, we must not forget about the structure itself. Depending on the number of storeys and area of ​​the house, the load that the foundation must withstand will also change. You should also take into account the materials from which the construction is carried out. In this regard, frame houses look very beneficial. Such structures weigh little, therefore, the foundation is not required so powerful.
• Another factor is the desire to have a basement. Such additional area not always possible. Much will depend on the proximity of groundwater and the characteristics of the soil at the site. But if these parameters allow, then the appropriate type of foundation should be chosen. For example, the pile or columnar option is absolutely not suitable.

The most common types of foundations

Now it's worth talking about the very varieties of foundations for the house. Over the centuries, people have invented a wide variety of types of foundations. Each of them can be ideally suited to certain conditions. Let's start the story with the most popular one - strip foundation.

Strip foundation

This type of base is used when building a house from any material. The most important thing here is the characteristics of the soil. If the soil has sufficient bearing capacity, then tape structures can be used. For difficult soils that have high humidity or are unstable (floating), this type of foundation is not recommended.

At its core, the strip bases for the house are a monolith of concrete. At the site of future construction, a trench or foundation pit is being dug (in the case when it is intended to build a basement). Then formwork is made, reinforcing structures are laid, and pouring is performed concrete mix.

The strip foundation is different:

• reliability and long service life;
• high strength;
• the ability to carry out all the work independently, without the involvement of specialists

The biggest disadvantage of this type of foundation is the large amount of work performed. It takes a lot of work to build such a foundation. Plus, for a full set of concrete strength, it takes about a month, and according to many experts, even several times more.

Pile type of foundation

If you are thinking about which foundation to choose for "difficult" soils, then many professionals will advise the pile type. In this case, wood, reinforced concrete or metal piles are used. With the help of special equipment, they are driven in or screwed in to the level of stable soils. Therefore, this type of foundation is suitable for almost any site.

Piles are installed at the corners of the building, at the intersection of the load-bearing walls, as well as at certain intervals on long sections. After installing the supports in their places, they are "tied" together using a bar or channel. After that, you can start building the house itself.

The pluses of the pile foundation include the following:

• speed of construction;
• saving material;
• the ability to use on any type of soil;
• long service life

In this regard, much will depend on the chosen material for the piles. If you use wooden logs, then such a foundation is guaranteed to last no more than ten years. When using reinforced concrete piles, we can safely talk about a hundred or more years of operation.

The downside is the complexity of the work. You are unlikely to be able to build such a foundation on your own. Firstly, it is necessary to carry out preliminary calculations, which can be quite complicated. Secondly, the use of special equipment is required. Another disadvantage is the lack of a basement.

Column foundation

A kind of symbiosis of the first two variants of the foundation is the columnar type. In this case, shallow pillars are used, which are located in the same places as the piles in the previous case. This type of foundation is used in the construction of timber or frame houses. Such structures do not require a foundation that can withstand heavy loads.

For the construction of pillars, you can use wooden logs, brick or rubble masonry, poured concrete. The choice of material will depend on the properties of the soil at the construction site.

For example, if the soil has a high moisture content, then it is better to use rubble masonry or concrete structures.

The pluses of the columnar type of foundation include a small consumption of material. In addition, the construction itself will not take much time and your efforts. But it is worth remembering that such a foundation cannot be erected on too "difficult" soils and during the construction of houses that exert a heavy load on the base.

Slab foundation

Another fairly common type of foundation is monolithic or slab. If your site has subsiding, mobile, heaving or clay-sandy soils, then this type of foundation can be considered one of the best. The foundation is a poured concrete slab.

For its construction, a foundation pit is being dug. Its depth will depend on the mass of your home. Further, the bottom of the pit is compacted and a sand and gravel cushion is erected on it. Then a layer of concrete of 5-10 centimeters is poured. After its partial solidification, a frame is made of reinforcement. After that, the rest of the foundation is poured.

The slab type of foundation is highly durable. Therefore, it can be used in construction multi-storey buildings, including the use of heavy materials (brick, stone, and so on). Since the monolithic foundation is a single whole, it easily tolerates ground movements. Plus, you can easily make such a base yourself.

But a monolithic or slab foundation has its drawbacks. First of all, it is worth mentioning the high cost. You will need to use a large number of concrete mix, and of high quality.

Each type of foundation has its own positive and negative sides... Of course, most private developers will want to minimize their costs and do as much of the work as possible without the involvement of specialists. But here, first of all, it is worth starting from the properties of the soil on the site.

If the soil at the construction site is stable and has a high bearing capacity, then the best (and most used) type of foundation will be strip. He is able to withstand heavy loads.

And if the house is made of light materials, for example, from a wooden beam or frame structures, then it is quite possible to choose a columnar base. In this case, you can significantly save time and materials.

It is quite another matter if the soil is "difficult". If the site is dominated by clay soils or loam, then it is better to give preference to the pile type of foundation. Of course, such a foundation will require the involvement of specialists, but your house will be more stable, which means it will stand much longer.

Video: The correct strip foundation for the house

What type of foundation to choose

Construction is a complex and costly business that requires a scientific, rational approach. Therefore, before choosing the type of foundation, you will have to answer several important questions:

• what will the house be like? (material, number of storeys, will there be a basement)
• what are the geological conditions at the construction site?
• to what depth does the soil freeze in winter?
• at what depth is the groundwater?
• how much do you intend to pay?

Reliability and quality are not quickly executable, especially in construction, where each stage depends on the previous one, and a lot of calculations are needed to complete at least one of them in a short time.

The foundation performs a buffer function - it minimizes the possibility of soil subsidence, displacement of the walls of the house and provides. The future house depends entirely on the type of foundation, since it is its foundation and support.

How deep to lay the foundation is calculated, taking into account the climate of the area. Our country is characterized by cold winters, so waterproofing and thermal insulation are a must. Therefore, it is better to build efficiently, thoroughly, and in one season.

The wrong choice of the type of foundation and the subsequent precipitation of the building are the reasons for skewed porches, verandas, terraces, problems with opening doors, and sometimes even more large-scale disasters: breaks in communications (water supply, gas pipes, sewers),.

It is not worth saving on the basics, even if the costs for them amount to 20% of the total cost of the house, because subsequent repairs will cost an order of magnitude more. The loss of finances is not yet the worst thing, sometimes it is impossible to restore or fix the structure.

The bases can be tape, slab, columnar and pile.

Slab (monolithic) type of foundation

Monolithic, also called floating, are some of the most reliable foundations for buildings. different kind located on a site with poor geological conditions:

• high groundwater table
• heaving / subsiding soil
• waterloggedness

Consist of monolithic reinforced concrete slabs located on bulk soils. Reinforcement is carried out not only along the perimeter, but also over the entire area of ​​the structure. This provides rigidity, strength of the foundation, which in turn helps in the fight against deformations. These qualities are especially important in autumn or spring, when the soils are unstable due to temperature changes.

Also, slab foundations are used in the construction of basements or basements: they protect well from moisture. Thanks to Swedish technologies and modern hydro- and heat-insulating materials, insulated boards are becoming very popular.

If, for example, a garage is planned under the house, then it is better to use a slab foundation for this.

The construction of a monolithic base begins with digging a pit with special equipment (or manually, if the volume is small). The pit should be slightly larger than the foundation itself around the perimeter. The bottom is carefully tamped down and layers of sand and gravel are poured - making a "pillow". Each of the layers is separated by geotextiles. Then the slab is poured into the formwork: first, a thin layer is poured, then it is reinforced and the remains of concrete are added. After that, a monolithic tape is arranged on such a slab under the walls, and the slab itself can serve as a floor for basements. The thickness of such a structure rarely exceeds 0.2 m.

Advantages of a monolithic foundation:

• the reinforced slab does not deform and moves with the ground, thereby ensuring the stability of the entire building
• the slab is reinforced not only outside, but also inside, which is the reason for the strength, stability and durability of the foundation
• resistance to temperature extremes, thawing and freezing, as well as high humidity
• moving soils are not scary
• can be used in places where groundwater washout is high. Provides waterproofness

Benefits of a slab foundation

Disadvantages:

• the cost of floating bases is high due to the large number earthworks and mandatory reinforcement.

Shallow tape foundation

This type of foundation is located around the perimeter of the structure. It has the same width throughout its length and is more commonly used for stone, wood and concrete walls. If future home is large, it is advisable to use a strip foundation.

Light one-story stone, chopped or frame buildings are best installed on shallow foundations (less freezing depth). This type is used for stable geological foundations (weakly heaving), but if you make reinforcement and prepare a "cushion" of sand, then it can be arranged on any soil.

The material for a strip foundation with shallow depth is not only concrete (monolithic or prefabricated), but even stone or brick. But it is undesirable to use a brick, since it is short-lived - it absorbs water.

Strip foundations are monolithic and prefabricated.

Under the monolithic strip foundations (in the trench), formwork is first installed, already in which the reinforcement strapping is poured with concrete. Such a foundation is strong and can withstand fairly high loads of complex-shaped buildings.

Interesting fact!
Modern trends in construction are gradually leading to the idea of ​​ending the use of wooden formwork. Everything construction companies trying to achieve greater smoothness of the ends of concrete bases for greater frost resistance, and wood does not solve this problem. Yes, and all the time it is necessary to erect wooden formwork in a new way. Instead, they are now using reusable metal formwork, which makes it possible to obtain neat foundations.

The popularity of individual blocks has subsided somewhat, and in European countries they have not been used for a long time. Such blocks are produced in specialized factories. They are placed in the pit with the help of cranes, and already there they are fastened together with a solution of cement. Perhaps this technology is simpler than pouring concrete into the formwork, but practice confirms that the quality of such foundations is worse. Monolithic structures are much stronger than prefabricated ones.

Advantages of strip foundations:

• even distribution of the acting load. Durability and reliability
• saving money and materials
• ease of reconstruction

Disadvantages:

• the need for a simple architectural layout

Screw pile foundation

The pile foundation is effective for construction on swampy soils, problem soils (for example, the city of St. Petersburg).

It is a pipe with pointed tips. Such piles are screwed into the soil layer. They will serve as a support for the reinforced concrete slab overlapping them from above.

Piles are screwed in to different depths, depending on the mobility of the soil, this is what distinguishes the pile foundation from the columnar type.

The pile material can be different:

• metal
• wood
• reinforced concrete

Reinforced concrete pile structures are nevertheless more durable, the possibility of their operation reaches more than 100 years.

Summing up, it turned out that given type foundation is low-consumable in materials, effective on difficult soils, but requiring special small-sized equipment and complex engineering calculations.

It is a set of pillars installed at the main nodal points of the building with a distance of no more than 3 meters from each other. The material for columnar foundations is concrete, stone (natural), brick. The posts are overlapped with strapping beams (made of metal or wood), which makes the base stiffer.

Also, the distances between the posts must be covered with connecting walls - (it has its own design with ventilation holes, base). It can be done from bricks, rubble masonry or concrete with a thickness of at least 0.1 - 0.2 meters.

It can also be monolithic or prefabricated.

A monolithic construct is used provided that the groundwater is deeper than 1 meter. During its construction, holes for pillars are dug (drilled). Concrete is poured into the previously prepared formwork, and the distance from the formwork wall to the pit wall should be more than 0.1 meters. Reinforcement must also be provided, otherwise the foundation will not have the required strength.

Reinforced concrete prefabricated bases are erected on damp soils. These pillars are attached to the base plate. This type of building is not intended for moving layers, otherwise the entire building may collapse.

Benefits of the columnar type:

• material consumption and labor costs are 2 times, and in some cases even 5 times cheaper, even (the most inexpensive of the above) strip foundations

The disadvantages of a columnar foundation are:

• mandatory device basement floor
• the inability to use in areas with elevation differences is dangerous, as overturning may occur
• not used for heavy buildings on sandy (sandy-clay) rocks

What is the best foundation on clay soil?

The clay type of soil is characterized by the presence of a large amount of water in its composition (due to the fine dispersion of particles), freezing, it expands, and as a result, swells - deforms. The base breaks, under the influence of forces, and the building itself suffers.

There are several varieties of clay soils, but on all of them the choice of foundation should be in favor of:

• tape recessed
• slab
• pile

When erecting any of these foundations on clayey rocks, it is necessary to use special technologies and rules.

For example, a tape base on such soils should be laid on a thick sandy base, and itself made of insulation (foam). Often the cross-section of such structures is trapezoidal (the base is one-third wider than the top). To remove excess water from the foundation on clay, a drainage system is used.

What is the most reliable foundation?

Its grip on hard ground provides maximum stability and strength to any structure. Sometimes you have to drill deep enough.

Pile foundations properties:

• simple installation - despite the need for special small-sized equipment, it is constructed several times faster than other types of foundations. Unlike other varieties, the pile base does not require heavy construction machines and a large number of workers.
• work is carried out by 2-3 specialists
• piles are durable, not afraid of corrosive destruction and water
• versatile, as they can be used absolutely in any areas, especially with problem soils

In second place in terms of reliability is the floating type.

This type, despite its high cost, withstands the impact of poor geological conditions of the site: it retains high strength qualities. When building on clay rocks, it requires a sandy "substrate" and high-quality reinforcement.

Is it necessary to choose a pile or slab foundation type for the construction of private residential buildings? Of course not. Specialists will always find the best option in terms of finance and security.

Today we will consider the advantages and disadvantages different types foundations used in suburban cottage construction... There are many types of foundations used in low-rise cottage construction. For a competent choice of the type that is right for your future structure, it is a good idea to know their advantages and disadvantages, their differences and similarities, as well as their areas of application to find out what is the best foundation for the house.

Monolithic slab foundation.

This foundation is not very common in cottage construction, since it requires a lot of costs for its construction. The essence of this type is the construction of a single monolithic slab under the house.

The slab is made directly at the construction site of the future cottage by pouring a liquid concrete mixture into a previously built one to obtain the desired shape formwork containing a reinforced frame inside.

Monolithic reinforced concrete foundation in the photo

Often, to reduce costs, instead of a monolithic slab, a monolithic reinforced concrete lattice is made, which can also be attributed to a slab type of foundation.

Such a foundation has a large mass, fits well on the ground, evenly distributing the load of the entire mass of the building on the ground. Accordingly, the scope of its application is heavy structures (for example, brick cottages), as well as places where it is required to obtain a good distribution of the building's load on soft ground.

The foundation is tape monolithic reinforced concrete.

The structure is very similar to the belt assembly. The same tape is being built. However, it is not based on ready-made building units of material, but liquid concrete poured directly on the construction site into a pre-reinforced formwork.

In the photo, the formwork device for the strip foundation

In this regard, a monolithic tape is similar to a slab. With respect to the national team, this type has both its pros and cons. The absence of seams in the monolithic tape is a plus for the prefabricated type.

On the other hand, monolithic construction takes, as a rule, longer: construction of formwork and reinforced cage, delivery of ready-mixed concrete to the site or its production directly on its site, curing the concrete for a long enough time to gain the necessary strength.

The distribution of the load of the cottage on the ground is uniform. The foundation has large area bases (sole), thanks to which such a foundation is suitable for construction on not very hard soils.

Construction of a pile foundation.

It is usually not used in the construction of cottages due to the complexity of its implementation, the need for a pile driving machine and the lack of a special need for its construction.

The basis of such a foundation is driven or rammed piles. Such piles are installed with one end deep into the ground. The idea is to reach solid ground with high bearing capacity.

It is on this solid ground that the cottage rests after construction thanks to the piles. Accordingly, this type of foundation is typical for use on soils where there is a large upper layer of soft soil.

It can also be used on wet soils with a large frost penetration depth. In this case, the piles are always driven below the freezing depth.

Piles are more economical in terms of consumption building material a tool, however, its use without the use of special expensive equipment seems to be little real.

Pile-screw foundation pros and cons.

One of the acceptable options in cottage construction can be considered a pile-screw foundation, in which ready-made special piles with a pointed end and a special screw blade are screwed into the ground.

For this, you can use special hand tools. You can independently bury such a pile in 1-2 hours to the required depth (usually 1.5 - 2.5 meters).

Typically, a pile has a relatively small cross-sectional area. You can increase the area to reduce and more evenly distribute the load of the cottage on the ground in the following way.

First, an increase in the total number of piles. In this case, the total supporting area of ​​the foundation increases and, accordingly, decreases specific gravity buildings on the ground.

Secondly, an increase in the cross-sectional area of ​​the pile itself. In this way, the total number of piles used can be reduced.

Both the pile and pile-screw foundations are characterized by the absence of a basement. Both types are not used on hard soils such as debris or rock.

Read more about this type of foundation

Column foundation for the house.

This foundation can be either prefabricated, when it is based on pillars assembled from ready-made or individual cast blocks, or monolithic, when the basis is made up of cast pillars at the installation site.

Thus, the cottage rests on these pillars. Accordingly, the pillars are located at the intersection of the cottage walls, under the most loaded places of the building, as well as along the entire perimeter.

The distance between the nearest pillars, their total number and the cross-sectional area of ​​each of them are calculated manually on the basis of strength materials or using engineering programs.

It is quite simple to build such a foundation, it is cheap, therefore it is often used in construction, but only for light buildings. A cottage, as a rule, is not one of these.

By the type of deepening, it can be not deepened or slightly deepened. In any case, such a foundation will be located above the freezing point of the soil. Therefore, he will not be able to withstand the heaving of the soil in winter. Hence, the limitations of its use are understandable: usually these are not heaving solid soils.

Now you yourself can determine which foundation is better exactly for your home.

The construction of the foundation is one of the main stages of building a house. In this case, the developer must answer to main question: which foundation to choose?

An improperly constructed foundation can cause destruction of the building. Therefore, it is necessary to choose carefully.

The main purpose of the foundation is the uniform perception of the load of the house and its structural elements, the transfer of the load to the foundation.

Depending on the method of support on the ground and the shape, foundations are divided into the following types:

• tape;
• columnar;
• pile;
• slab.

After studying the material and consulting with specialists, you can choose the appropriate type of foundation and save your time and money.

Strip foundations

This type is most often used in individual construction... As a material for you can choose rubble concrete, rubble stone, brick, concrete, reinforced concrete.

Strip foundations are commonly erected in basement homes and buildings with heavy walls. This type of foundation is installed around the perimeter of the house. Its device requires a large amount of materials and labor costs. Despite the laboriousness, such foundations are technologically quite simple. If you plan to build a house with a basement, warm underground, garage and basement, then it is recommended to choose a strip foundation.

Strip foundations are monolithic and prefabricated. Which one to choose depends on a number of factors.

When building tape monolithic bases, manually or with an excavator, they dig a trench 50-80 cm wide. The width of the trench should be about 10 cm higher than the width of the foundation itself on both sides. This is necessary for the device of the formwork, to which the reinforcing strapping is made. Next, the concrete mixture is placed in it.

The main advantage of monolithic tape bases is the ability to withstand significant loads. Such bases can be used in the construction of buildings of various shapes.

Foundation masonry from different materials: a) natural stone; b) cobblestone; c) crushed stone and brick; d) brick; e) clay.

Prefabricated strip bases are reinforced concrete or concrete blocks laid on mortar and tightened with strong steel wire. Such a foundation is durable and quick to erect. Its service life is up to 150 years.

This type is used for the construction of buildings of simple shapes, since the building blocks require trimming for the implementation of complex architectural tasks.

Prefabricated strip bases are inappropriate for the construction of buildings with a basement, since the presence of horizontal and vertical joints significantly reduces water resistance. And the device for additional waterproofing requires additional costs. The construction of such foundations on deep-freezing ones is economically unjustified, since it requires an increase in the amount of work.

Such bases are suitable for construction:

• houses with several floors, except for houses whose walls are made of piece materials, such as reinforced concrete panels, bricks;
• houses with a deep basement used for swimming pool, sauna or parking.

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Columnar foundations

The main structural elements are the pillars. Their construction requires almost 2 times less material and labor costs than the construction of tape bases. This type of base is ideal for the construction of cottages without a basement with light frame, cobbled, panel or chopped walls.

As a material of manufacture, you can choose rubble stone, rubble concrete, concrete blocks, solid ceramic iron ore brick.

The posts are installed at the corners and intersections of the outer walls. The pillars are placed with a step size of 1.5-2.5 m along the entire perimeter of the building. Strapping beams are placed on top. If the distance between the separately standing columnar bases is more than 2.5-3 m, it is necessary to lay massive reinforced concrete or metal randbeams.

The minimum cross-section of the pillars depends on the material of manufacture. For example, pillars made of concrete, buta-slab or rubble concrete should have a cross-section of 40 cm.Masonry from natural stone - 60 cm, pillars of brick - up to 38 cm.

Formwork design for a strip foundation.

Columnar bases are divided into prefabricated and monolithic. Which type to choose depends on the specific conditions.

For its construction, holes are manually dug in the ground or drilled using special equipment. The posts must have a reinforcing strap. It is needed to prevent the destruction of the column during seasonal ground movements. Formwork is also required, which can be round or square. It is necessary to provide for a gap between the walls of the pit and the formwork of at least 10 cm, which will avoid the deforming effect of soil movements on the post. After removing the formwork, sand or fine gravel is poured into it.

Prefabricated columnar bases are intended for damp and wetlands. They consist of reinforced concrete pillars and base plates. Wire and metal rods are used as reinforcement.

This type of base is usually not used in the construction of houses with a basement and basement. It is not used on uneven terrain due to the possibility of overturning by soil pressure from the side.

However, this type of foundation is the cheapest. It is most effective on heaving soils with deep freezing. On moving soils, such foundations are unstable to tip over.

When erecting columnar foundations, problems arise with the construction of the basement, since it is necessary to arrange a concrete lintel between the pillars.

The merits columnar bases are:

• less laboriousness in construction compared to other foundations;
• profitability.

Disadvantages of Columnar Bases:

• the need for a basement device;
• low stability in moving soils;
• the need to limit their use in the construction of buildings with heavy walls on sandy-clay soils.

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Slab foundations

They represent a solid or lattice slab of special prefabricated cross-reinforced concrete beams or monolithic reinforced concrete. They are usually erected over the entire area of ​​the building. Their use is optimal for heaving, unevenly compressed and collapsing soils. Because of this, the slab foundation is called floating.

It is most suitable for clay-sandy soils with a water level of less than 1 m from the surface and for the construction of multi-storey buildings on clay-sandy soil. Such bases can withstand vertical and horizontal ground movements.

Are:

• ease of construction;
• the possibility of construction in subsiding, heaving and moving soils.

The disadvantages include the relative high cost.

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Pile foundations

They consist of individual piles covered from above with a beam or concrete (reinforced concrete) slab. In individual construction, they are used extremely rarely, since their construction is laborious.

Pile foundations are intended for houses on weak soils when it is necessary to transfer significant loads from the structure to dense deep soils.

They are made from steel, wood, concrete and reinforced concrete. They can be combined. Piles lowered into the ground completely finished form, are called hammer-in. Piles made in channels drilled in the ground are called rammed piles.

The type of behavior is distinguished:

• piles-racks, which have solid ground under them and transmit pressure to it;
• hanging piles, which are used for deep burial of solid soil.

Wood piles are economical but rot quickly in wet soil. Their service life does not exceed 10 years.

The service life of reinforced concrete piles reaches 150 years. They are intended for the construction of multi-storey buildings.

The advantages of pile foundations include:

• less shrinkage;
• economy in comparison with other types due to the reduction in material consumption;
• possibility of application on soils with low bearing capacity.

Their disadvantage is the need to use special equipment during installation.

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Determination of the depth of the foundation

It is important to correctly determine the depth of the foundation.

What should be the level of the depth of the bookmark, first of all, depends on the specifics of the relief. If the building is without a basement, then the depth of the laying will depend on underground utilities, the nature and magnitude of the loads.

Foundations are subdivided into:

• buried (profile);
• shallow (shallow).

Profile foundations are mounted below the level of soil freezing. Shallow concrete foundations are installed at a depth of 50 cm.

Profile foundations are used in the construction of heavy structures made of brick or wood, clad with brick. Therefore, the cost of such a foundation is comparable to the cost of the house itself. Shallow foundations are optimal for the construction of timber frame or lightweight panel houses, garages and outbuildings.

When choosing the type of foundation, it is necessary to take into account the type of soil prevailing on the site. This can be determined by a geotechnician.

It is determined by the magnitude of the load under the influence of which the soil settles. The deformation of the soil occurs not only from the load, but also from temperature changes. When freezing, groundwater expands and pushes up the base. Each type of soil has its own draft, therefore the final decision on the choice of the type of foundation is made after carrying out geological procedures.

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Determination of the depth of soil freezing

For unheated premises, the freezing depth is taken 10% more than the average. The depth of freezing is measured from the ground, in an unheated building with a basement - from the level of their floor. For heated premises, the freezing depth will be less by 20-30%.

A foundation erected below the freezing depth cannot guarantee protection against the effects of frost heaving.

To reduce the likelihood of deformation, the following methods are used: reduce the side surface of the base, give the base a trapezoid shape with a narrowing upward, fill its sinuses with non-porous soil, create a side surface using a material with a low coefficient of friction.

It is influenced by the level of groundwater. It is determined by carrying out special engineering and geological studies by drilling pits, soil samples and chemical analysis of water. On construction sites wooden houses the depth of the wells can be up to 5 m. If a brick or stone house is being built, the depth of the wells will be 7-10 m. At the same time, it is necessary to drill at least 4 wells in the corners of the house.

When choosing the type of foundation, the main factors are the design and purpose of the house.

In the case of building a brick cottage, you need to decide on the height of the house and the thickness of the walls, the presence of a garage, basement and utility rooms. For such a cottage, it is recommended to lay out a strip foundation with a depth corresponding to the type of soil. Walls made of reinforced concrete blocks and panels are erected mainly on strip foundations. The use of slab foundations is possible in the construction of buildings on the slopes of hills, clay-sandy soils and swampy soils.

When building a lightweight wooden house or a frame-panel structure, you can save money on the foundation without compromising quality. For such a house, the use of a shallow foundation would be optimal. To do this, you need to remove the top layer of soil 50 cm thick, then lay the rubble and tamp it. Then a drainage pipe is installed around the entire perimeter. A road membrane-film is covered on top of the crushed stone layer. A layer of compacted wet sand and insulation are placed on top of it. Next, waterproofing is performed and reinforcement is strengthened. At the end, concrete is poured, which forms a solid monolith.

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Choosing the type of foundation

Here we will try to answer the question: what type of foundation to choose?

For the right choice type of foundation, you need to understand that the soil and foundation are unified system... It is necessary to have an idea of ​​the mechanism of interaction of five elements: foundation, house, soil, groundwater and air temperature.

The main planning issues for building a house are:

• what will be the load from the house, which is transmitted through the foundation, and will the soil withstand it;
• what effect groundwater will have on the ground in the warm and cold seasons.

First of all, the properties of the underlying soil are important. The durability of the foundation and the house built on it depends on the sufficiency of the bearing capacity of the soil, its ability to retain water and the presence of resistance to deformation with changes in temperature and moisture saturation.

Consider the main reasons for soil movement that affect its bearing capacity.

Settlement of the soil can occur under the influence of its own weight and external load. Unlike subsidence, there is no change in the structure of the soil during settlement. Air and water are squeezed out of the soil. Settlement can be immediate or long-term.

For example, clay settles over several years due to the fine, scaly structure that retains water. Long-term sedimentation is characteristic of porous organic soils. Under the load of gravelly, coarse sandy and rocky soils, the sediment ends by the end of construction. Subsidence of the soil with a change in the structure can occur both under the load from and its own weight, and when the saturation of the soil with water changes. For example, the crystal structure of chalky soils can weaken in the event of saturation with water or changes in the chemical composition of groundwater. As a result, the chalky soil will subside.

The movement of the soil in the form of rises and precipitation usually occurs when the volume of the soil changes:

• when their humidity changes as a result of swelling and shrinkage;
• when water freezes and ice thaws in the ground as a result of frost heaving and thawing of the ground.

Horizontal displacements occur with erosion of slopes, subsidence, large vertical displacements of soils. The deformation of the earth's surface in the form of subsidence is associated with the formation of natural or man-made underground cavities, a decrease in the level of groundwater. This is typical for clay and organic soils.

The deformations of soils in the form of subsidence, settlements, displacements in the horizontal plane occur from the application of an external load. For example, from the movement of heavy equipment, loads at construction works, loads from the house itself.

Deformations of the second type in the form of horizontal and vertical displacements of the soil (subsidence under its own weight, subsidence, expansion with moisture saturation, frost heaving) are not associated with external load.

Uneven soil deformations are dangerous for the foundation. Their reasons may be the heterogeneity of soils, the presence of lenses and large inclusions, the unevenness of their compaction during construction work, the unevenness of soil moisture, the wedging of soil layers at an angle.

To predict the safety of the foundation and structure and prevent deformations that can lead to the destruction of a house, the concept of the bearing capacity of the soil is used - the resistance of the foundation.

It is necessary to compare the bearing capacity of soils with the load from the building, wind, snow, operational loads, taking into account the safety factor.

The bearing capacity of soils increases significantly when the foundation is buried into the ground to a depth of more than 2 m due to the appearance of additional resistance to the load from the building by perpendicular forces from the lateral soil pressure. These forces are not taken into account at a depth of less than 2 m. When the foundation is deeply laid, the soil acquires the properties of a liquid: a buoyant force acts on a body (foundation) immersed in a liquid.

Foundations for houses can be very different. They are made from different materials and using different technologies. The choice is made separately for each specific case. It is impossible to say clearly which foundation is better. Even when building the same houses in different places, the type of support part and the cost of it can be radically different.

The types of foundations for a private house are chosen based on:

• bearing capacity of soils on the site;
• soil moisture and groundwater level;
• terrain;
• the need for a basement;
• number of storeys of the building and the mass of its structures.

All these factors must be taken into account at the same time. It is difficult for a non-professional to choose unmistakably what foundation is needed for construction. If possible, it is best to contact an experienced designer. At the same time, he needs to provide information about the soils on the site and the structural features of the structure.

A pit sample is the easiest and cheapest way to find out the type of soil and the depth of the groundwater

Before choosing the type of foundations, geological studies are necessarily carried out. To build a house in the private sector, you do not need to order an expensive procedure. It will be enough to roughly find out the type of soil and the depth of their occurrence. This work can be done in two ways:

1. drilling;
2. fragment of pits.

Types of foundations

To answer the question, what are the foundations, you need to consider several classifications. For the construction of a building, the types of foundations are distinguished by design and manufacturing method, as well as by material.

The choice of the foundation, depending on the material, is proposed to be made of three options:

1. wood;
2. metal;
3. reinforced concrete.

The first option is currently practically not used. Wooden piles were widely used in the past for erecting buildings in swampy areas. But the disadvantage of wood is its high susceptibility to decay and low strength. In modern conditions, it is not worth considering such types of foundation for a private house.

Another option for construction is metal. It has a limited area of ​​application. Only a certain type of foundations for wooden houses and frame buildings is made of it - pile-screw.

Reinforced concrete types of foundations for a house are most widespread. This is because concrete performs very well in compression. These are the loads that arise in the underground part of the building. There are exceptions, but in this case, metal fittings are included in the work. Due to the combined action of concrete and reinforcement, reinforced concrete varieties differ high reliability and durability.

When using a reinforced concrete option, the question almost always arises: which foundation to choose, prefabricated or monolithic?

The prefabricated technology assumes the use of prefabricated prefabricated elements. Such types concrete foundations can be built quickly, there is no need to wait time for material hardening. But these options are more intended for mass construction. They allow you to perform work on an industrial scale in a short time, but require special heavy-duty and lifting equipment. It will be difficult and costly to make such a foundation for a house on your own.

An excellent option for private construction will be monolithic types of foundations and their various variations. Practically no special equipment is required for manufacturing. If desired, all the work can be done manually. But still, to improve the quality of work and reduce the timing of their implementation, it is recommended to order ready-made concrete at the plant and its delivery by special mixers. In addition to the mixer, it is worth ordering a concrete pump. This technique allows the mix to be quickly and effortlessly distributed into the formwork.

The disadvantage of the monolithic technology for the manufacture of foundations will be an increase in the construction time. A stone made of this type gains strength on average within 4 weeks. All this time, it is prohibited to erect on the supporting part of the wall.

In addition to differences in material and technology, it is worth highlighting the classification by design features... Before choosing a foundation, there are four main types of foundation to consider. There are also several modifications within each group.

For the construction of buildings, the following types are used:

• tape;
• plate;
• pile;
• columnar.

Strip foundation

If you answer the question, what kind of foundation is needed for a building with a basement, then the answer will be unambiguous - tape. This is the best and almost the only option. You can also use a slab base for this purpose, but the tape will have to be used in this case as well.

What is the strip foundation made of? It can be made from monolithic or precast concrete. The device assumes the presence of three types of tapes, depending on the depth of placement:

You will also have to choose a strip foundation according to the type of section. It can be rectangular or T-shaped. The second option assumes the presence of a widening from the bottom in the form of a pillow and has a higher stability and bearing capacity. It is used for brick or concrete buildings. In the production of the tape using the prefabricated technology, special FL foundation pads are used to ensure broadening, their production is carried out in the factory.

Slab foundation

The stove is a good option for fragile soils. Just like tape, this type can be buried, shallow and not buried. The first option, due to its high cost, is rarely used.

If we compare the foundations, then the slab has the greatest bearing capacity at approximately the same labor costs. Only some types of piles can compare with it in terms of bearing capacity on weak or swampy soils. But they will cost much more and require more effort and the availability of special equipment.

Most often, in the construction of private houses, an unburied slab is used. You can also consider. It will be an excellent solution for heaving soils in the northern regions.

Even a layman can make a stove. In private construction, the thickness of the structure is usually taken as 200-300 mm. Such a base can withstand a two-story brick house... Reinforcement is carried out with meshes in two rows. If the thickness of the slab is 150 mm or less, then one row of reinforcement should be laid.
Advice: for pouring it is recommended to use concrete of grades B20-B25. This is due to the fact that the slab foundation, in addition to compressive loads, perceives bending effects, for which concrete does not work very well. To avoid the appearance of cracks, you need to take care of high-quality reinforcement and strong concrete.

The stove is used in the following cases:

• construction of a brick or concrete house without a basement on marshy or fragile soils;
• erection of buildings with a high location of the groundwater level (at a distance of at least 50 cm from the earth's surface).

Also, the slab base is used in the construction of small forms of the building, which must stand on separate foundations to prevent uneven shrinkage. These forms include:

• basement entrances;
• porch;
• terraces;
• etc.

Pile foundation

Piles are the only reasonable option when building on soils with a groundwater level higher than 50 cm from the earth's surface. They also allow you to build a house without significant effort on a fragile foundation and with strong elevation differences on the site.

In this case, there is no way to provide a basement. The plinth is covered with finishing materials, while leaving ventilation gaps and openings for free air movement under the house.

A grillage is installed along the cut of the piles. It can be made of wood, reinforced concrete or metal. The choice of material is carried out depending on the material of the walls and the piles themselves. For example, when building a wooden house, it is reasonable to use a harness made of wood, and when erecting reinforced concrete piles, it is advisable to use concrete.

Piles are classified by material, manufacturing method and immersion. I can be made of metal or reinforced concrete, both in a factory way and on construction site... There are four most common types of piles:

Column foundation

This option has the lowest bearing capacity of all. The approval does not affect special glass-type pillars, which are used as a base for columns in the construction of public and industrial facilities.

Before choosing a foundation for a house, you need to carefully study all the necessary information. Irresponsible attitude can lead to cost overruns, distortions of the building during operation or other troubles.