What type of foundation is the most reliable? A guide to pouring your own home foundation. Factors for choosing the type of foundation

The foundation is the foundation of the house, and this is not a figure of speech at all. The durability of the building depends entirely on how correctly the type of foundation is chosen and how it is executed. Leaning houses and cracked walls of the dacha only once again convince of the increased responsibility of the work associated with the design and arrangement of the foundation. The first thing everyone who starts construction should do is choose the type of foundation for a private house, and for this you need to take into account a lot of factors and know key features all types of bases.

No. 1. Types of foundation by type of prefabrication

Depending on whether factory elements are used during construction, or whether they are all formed directly on the site, foundations are divided into:

monolithic. For their manufacture, formwork is arranged into which it is poured;
prefabricated monolithic obtained by filling finished component elements with concrete;
prefabricated foundations are constructed from factory-produced reinforced concrete products.

Naturally, monolithic foundations are much stronger than prefabricated monolithic and, even more so, prefabricated foundations, but they require more time and effort for arrangement.

No. 2. Types of foundation by design

All foundations used in private construction can be divided into four groups:

strip foundations- this is a continuous canvas made of reinforced concrete (much less often from), which is laid under all the load-bearing walls of the house and has the appearance of a closed contour or ribbon, which is where the name comes from. The most common type;
slab foundations also called “floating”, they are a solid monolithic concrete slab, which allows the load to be distributed most evenly;
columnar foundations, as the name suggests, are a system of pillars made of concrete, brick, stone, less often wood, and located at an even distance from each other in the locations of the load-bearing walls and corners of the future house. For reliability, the pillars are combined with a grillage (a frame that connects all the pillars), but they can do without it. This type of foundation is suitable for small, lightweight houses;
pile foundations consist of supports that are screwed or driven into the ground (the supports of a columnar foundation are installed in holes) to a relatively great depth. Piles can be reinforced concrete or metal, and are used on loose and heaving soils.

The choice of the type of foundation for a house depends on the number of floors and dimensions of the latter, the materials of the walls and ceilings, as well as the type of soil, the level of its freezing, the depth of groundwater, the presence of underground water, and the need to equip the basement.

No. 3. Strip foundation for a private house

The most common type of foundation When building a private house, it is considered to be strip. It is a strip or frame made of concrete, which is laid under load-bearing walls. A sand and gravel cushion is formed under the concrete, which allows for a more even distribution of the load on the soil and eliminates the need for more serious soil preparation before laying the foundation. The sand and gravel cushion acts as drainage and protects against the effects of groundwater. The foundation requires and.

The main advantages of a strip foundation include:

the ability to withstand decent loads, so it is used in the construction of both relatively light and 2- and 3-story brick buildings;
the ability to use such a foundation for arranging a basement;
The shape of the strip foundation can be any (with the exception of prefabricated structures);
minimum amount of excavation work.

Cons:

Strip foundations come in two fundamentally different types:

monolithic;
made.

Monolithic strip foundation formed by arranging formwork and pouring sand-concrete or rubble concrete mixture. It can be of any shape, and due to its integrity, excellent thermal and waterproofing qualities, as well as strength, are ensured.

Prefabricated strip foundation They are created from ready-made ones, which greatly simplifies and speeds up installation. Individual parts are fastened with cement with reinforcement, the structure is inferior in strength to a monolithic one, and its main disadvantage– insufficient waterproofing at the junction of blocks, which in areas with increased level groundwater and in marshy areas may lead to premature resolution of such a foundation. Much less often prefabricated foundations are equipped made of brick, but their service life is shorter than that of concrete ones.

It is worth highlighting intermittent strip foundation, which is laid not as a continuous line, but in separate sections, but clearly under the load-bearing elements. This design allows you to save a lot of money when constructing lightweight buildings.

In those cases when there is weak soil under the strip foundation, its base needs to be expanded, and this is done by formation of ledges, resulting in a stepped design: the wide part (sole) will bear the main load. It is also possible to form a foundation trapezoidal: The lower wide part will become the main support. If groundwater located at a shallow depth, it is recommended to use and additionally protect it with bitumen mastic.

As is clear from the above, strip foundations can be erected from the following materials:

Based on their depth, foundations are divided into:

shallow(depth 50-70 cm) - option for slightly heaving soils, i.e. those that are little susceptible to frost heaving;
deep-seated laid at a depth of 20-30 cm below the soil freezing level. Used for the construction of heavy structures and in places with difficult soil.

No. 4. Slab foundation for a private house

The slab foundation is being equipped in areas with loose, heaving and moving soil. A monolithic concrete slab, located under the entire future building, prevents the negative effects of soil movements and allows you to evenly distribute the load of the house on the soil. Under the influence of swelling of the soil, this type of foundation is able to evenly rise and fall again (that’s why it is called floating) – cracks do not appear in its structure and the load-bearing walls of the house.

The slab foundation is made of several layers:

geotextiles;
sand and gravel cushion;
insulation layer:
concrete with reinforcing reinforcement frame.

The thickness of the main concrete layer ranges from 30 to 100 cm, only monolithic structures , so the concrete is prepared and poured into the formwork on site. In rare cases, ready-made concrete precast slabs, but this method is only allowed when constructing small, lightweight buildings, since the strength of such a foundation is not very high.

A sand and gravel layer is used to level the base; sometimes it is replaced with low-strength concrete. It is imperative to use when organizing such a foundation. If you need to build a large house, then it is recommended to build it on a concrete monolith expansion joints– the foundation is simply cut into several smaller parts. This helps prevent cracks from occurring.

Advantages of a slab foundation:

Cons:

inability to arrange a basement;
high cost, this is the most expensive of all types of foundation for a house, so its use is justified only in areas with loose soil;
the need for flat terrain, otherwise the site must be properly planned.

No. 5. Columnar foundation for a private house

A columnar foundation consists of pillars equidistant from each other, sunk into the ground. The pillars may be:

concrete with reinforcement;
brick;
wooden;
stone;
rubble concrete.

The most durable are concrete and rubble concrete, they can withstand heavy loads, brick pillars are inferior to them, and wooden pillars can only be used as a foundation for small wooden buildings (, etc.). To increase strength and reduce mobility, the pillars can be connected on top with reinforced concrete strapping beams.

It is recommended to install a sand layer about 50 cm thick under a columnar foundation - it will prevent heaving. The pillars are installed at a distance of 2-3 m from each other along the contour of the house, in the corners of the building and in the locations of load-bearing partitions. A columnar foundation can be:

monolithic. All supports are created on site, reinforced concrete or rubble concrete and wooden formwork are used;
made. For its construction, factory-produced concrete supports are used. They are installed on special “glass cushions” about 0.15 m thick.

The number and depth of pillars are calculated taking into account the type of soil and structure. If the building is small and light, then it is even permissible to use a shallow foundation (this is about half the standard depth) and a non-buried foundation (40-50 cm).

Advantages columnar foundation:

relative simplicity and low cost of arrangement;
Ideal for building small houses on stable soils.

Flaws:

No. 6. Pile foundation for a private house

It consists of a system of piles, long pointed posts that are driven or screwed into the ground directly or at an angle. The large length of such elements allows them to be used in areas with weak and loose soil, because they are installed at such a depth as to rest on stronger and denser layers of soil that do not freeze in winter. This principle allows the use of pile foundations even in the most difficult conditions. Connected from above with a concrete slab or beam - grillage. This type of foundation is used for the construction of wooden, panel and other lightweight houses, as well as fences According to the installation technology, piles are:

Among the main advantages of a pile foundation:

Possibility of installation on any type of soil, no dependence on groundwater level;
reducing the amount of concrete consumed;
reducing the amount of excavation work;
relative speed of installation.

Flaws:

No. 7. What is important to consider when choosing the type of foundation?

It is better to entrust the calculations and design of the foundation to specialists, especially if we are talking about a large house with heavy load-bearing walls and ceilings. If a private house or small dacha are built on their own and are light in weight, many people prefer to do without detailed calculations, which is not entirely true. To avoid mistakes, it is necessary to take into account a lot of factors, and the basic principles for choosing the type of foundation for a house and its arrangement are:

on very heaving soils, the foundation must be equipped below the soil freezing level. In conditionally non-heaving, the depth of the foundation can be 0.5-1 m;
The average and maximum depth of soil freezing are variable values, and they are not always easy to determine. The organization that owns the land must have the relevant data, along with other soil characteristics, otherwise you will have to conduct your own research. The most unreliable way is to ask the neighbors on the site, but the soil may be heterogeneous, so such data is not always accurate;
the more dense and moist the soil, the more it freezes in the cold season. The most difficult in this regard is clay soil, which not only swells, but also unevenly. The most effective way to prevent possible deformations is to replace difficult soil with sand or create a sand cushion;
sandy soil It is considered ideal for constructing any type of foundation and building houses made of brick and other materials; it allows water to pass through well and almost does not swell. Rocky soils practically do not swell, do not freeze and do not change their properties under the influence of external factors, but it is also difficult to organize a foundation in them due to their increased hardness. Clay soils require either the construction of a sand cushion or the use of piles;
if there are other massive structures located near the proposed construction site, then you should definitely take into account total load on the ground;
on silty and heaving soils it is better not to use strip and columnar foundations;
a pile foundation is justified only when other options are not suitable at all - it is expensive to construct.

The foundation will last for many years if you don’t forget to also take care of its waterproofing and insulation. Much also depends on the quality of the materials used and the responsibility of those who build the foundation.

At the design stage, the question arises as to which foundation is best to choose for the future home. The solution to this issue is important for the developer. The cost of the foundation of a building can be a third of the total estimated cost of construction, so you need to choose the most reliable and durable foundation. When determining the best foundation, the owner of a future home should always be guided by the price and quality of the foundation.

Main factors determining the choice of foundation

Let's consider the main conditions that influence the choice of foundation for a house. The properties of the soil base are determined by its composition, the level of groundwater and the depth of soil freezing.

Soil composition

According to their bearing capacity, soils are divided into three groups:

Weak soils

Peaty, sandy and clayey soils are considered weak soil foundations. For example, peat bogs are so unreliable that the construction of any structures on them is often avoided.

Clay soils, as a rule, are susceptible to heaving. Heaving, that is, a sharp increase in soil volume under the influence of moisture saturation, can cause foundation structures to be pushed to the surface of the earth. In the same way, frozen layers of soil affect the supporting structures of the building.

Weak sandy soils do not have high bearing capacity and can contribute to subsidence and destruction of the foundation of the house. On soils of this type, pile foundations with a grillage and monolithic reinforced concrete slabs, both supported on piles and without them, are laid.

Rocky foundations and rocky soils

Rocky foundations are the strongest. On such soils, strip monolithic and prefabricated reinforced concrete foundations are erected. Columnar supports with a grillage also serve as an excellent reliable foundation for buildings on such soils.

Dense soils

Dense soils are formed from cohesive rocks that can withstand heavy loads and are resistant to heaving.

On dense soils, monolithic strip and prefabricated reinforced concrete foundations are mainly erected, and columnar foundation supports are also widely used. Dense soils are reliable and acceptable for all types of foundations.

Soil freezing depth and groundwater level

These two factors determine the depth of the foundation. To create a reliable foundation for a structure, the depth of the foundation is determined below the freezing layers of soil and below the groundwater level.

During construction low-rise buildings of lightweight structures, the foundation is made shallow above groundwater, but below the depth of soil freezing.

Guided by the calculated load from the house on the entire supporting area of the foundation, the type of foundation, its dimensions and configuration are determined.

If several types of foundations can be used for an object under construction, then the decision as to which foundation is best is made based on the cost of its construction and reliability.

Main types of foundations

Strip foundations

According to the depth of their foundation, strip foundations can be shallow and deep foundations. Shallow tapes are used mainly in the construction of low-rise buildings made of lightweight structures (foam blocks).

In other cases, foundation strips are laid below the groundwater level, creating powerful foundation structures with high load-bearing capacity. Strip foundations can be either monolithic reinforced concrete or prefabricated reinforced concrete strip foundations.

Strip monolithic reinforced concrete foundations

Strip monolithic reinforced concrete foundation is one of the most common types of foundations for buildings and structures. The construction of such a supporting part of the house requires large expenses for excavation and reinforcement work, as well as for the installation and dismantling of formwork. All this is justified by its great strength and high load-bearing capacity, which allows the construction of multi-story buildings from heavy structures.

What kind of foundation is best to lay on dense soils? The solution to the issue will certainly be made in favor of the construction of a strip foundation.

The question of which foundation is better for a house with a complex wall configuration in plan will also not raise doubts in favor of choosing a strip monolithic foundation.

Precast concrete strip foundation

Compared to monolithic strips, bases made of prefabricated reinforced concrete blocks are more economical. Installation of prefabricated reinforced concrete blocks does not require labor costs for installing formwork, reinforcing work and pouring concrete into the foundation.

Both shallow and deep foundations are installed from prefabricated reinforced concrete blocks. Factories for the production of reinforced concrete products offer a wide selection of reinforced concrete foundation blocks.

What is the advantage of prefabricated blocks over a monolithic base? Installation of blocks does not require labor-intensive work on installation and dismantling of formwork, as well as its reinforcement. The construction time for the foundation is significantly reduced due to the absence of time spent on concrete hardening. Reinforced concrete blocks are easy to transport and store.

Columnar foundations

Columnar supports are placed in plan along the line of load-bearing walls, in the corners of the perimeter of the house, as well as in places where loads from various internal loads are concentrated technical equipment Houses.

Columnar supports can be shallow or deep. Support pillars can be used instead of a strip foundation. The supports are placed in increments of 1.5-2 meters. When comparing the strip base with support pillars, the cost-effectiveness of installing columnar supports is noticeable.

The savings lie in significantly lower volumes of excavation and the absence of formwork work. However, one should not forget about the costs of installing a grillage. All doubts regarding the choice of foundation type will be resolved by a comparative technical and economic calculation.

Slab monolithic foundation

Monolithic reinforced concrete slab can act as an independent supporting structure of the building, or act as a grillage for a pile foundation.

Such structures are erected on soft soils. A reinforced concrete slab has a high load-bearing capacity, but is an economically expensive structure.

Piles

The main purpose of piles is to transfer the load from a building through soft soils to denser soil layers.

The most common types of piles:

Reinforced concrete piles;
Bored supports;
Casing;
Shell piles;
Metal screw supports;
Wooden supports.

Reinforced concrete piles

Reinforced concrete piles are manufactured at the factory. Markings for the installation of piles are made on the support lines of load-bearing walls, in the corners of the building and in places where vertical loads are concentrated. Reinforced concrete supports are installed using pile driving equipment.

Bored piles

Reinforced concrete pipes are installed in drilled holes. Reinforcing cages are installed inside the pipes. Then pour concrete with layer-by-layer compaction. Bored piles are used in densely built-up areas. In such places, a piling installation can cause unwanted deformations in the load-bearing layers of the soil. All this can negatively affect the foundations of nearby buildings and structures.

Bored piles are mainly used in industrial construction.

Casing pipes and shell piles

Casing pipes and shell piles are used in the construction of large industrial facilities. Installation and installation of supports of this type is possible using high-tech equipment.

Screw piles

Screw piles came into civil engineering in the second half of the last century from the military industrial sector. They are indispensable for quickly forming a reliable foundation for small structures. Developers use screw piles not only on weak clay soils, but also on dense soils.

Small screw supports are installed by two people by rotating the pipe using a lever. A lever in the form of a pipe is passed through a hole in the upper part of the support and, through the efforts of two workers, the pile is given a rotational translational vertical movement.

Watch a video detailing the pros and cons of screw bases.

The pile foundation is prepared in 5-7 days, depending on the size of the construction field.

Wooden supports

Wooden posts with pointed ends are driven into the ground using hand tools or a piledriver. Most often, wooden piles are used in the construction of light outbuildings.

Before you start building a house with your own hands, it is worth asking the owners of neighboring houses about the foundation structures of their buildings. This information will help you make the best choice of foundation for your home.

To make the foundation correctly, you need to carefully study the options for construction types and their features. The construction of the underground part is carried out taking into account the following requirements:

economic feasibility;
reliability;
strength;
durability;
sustainability.

Before starting construction work, a soil study should be carried out. The choice of the right type of foundation is influenced by the total weight of the house, the strength of the soil and the groundwater level. A foundation that is carefully made and built in compliance with technology will last a long time and will not cause problems during operation.

Preparatory stage

It’s worth starting with pits or drilling. The main goal of this activity is to find out what soils are located on the site, as well as to find out the level of groundwater. The foundation must be laid in compliance with the rule: the mark of the sole must be at least 50 cm above the level of the water horizon.

How to do soil testing correctly? Two methods are used for this:

excerpts of pits (deep holes, dimensions in plan are usually 1x2 m);
manual drilling.

In the first case, the soil on the walls of the pit is examined. They also check to see if water has left the bottom. In the second option, the soil on the tool blades is examined.

Once you have determined what kind of soil is on the site, you will need to find its strength indicators. This can be done using special tables.

The cost of laying the foundation for a house can be up to 30% of the estimate for the entire building. To avoid cost overruns, you need to perform a calculation that will allow you to find the optimal design parameters that will simultaneously guarantee minimum costs, strength and reliability. For your convenience, you can use online payment.

Types of foundations

Building a foundation with your own hands involves the use of several technologies:

ribbon;
combined options.

Columnar supports have a low load-bearing capacity. It is possible to install monolithic pillars or assemble them into compact concrete blocks. Both options are great for DIY projects.

There are three types of pile foundation for a house:

driven (not recommended for private buildings due to the need to attract equipment);
(suitable for building a brick or concrete house);
(ideal for light wooden buildings).

Piles make it possible to reduce the amount of excavation work. There is no need to dig trenches or pits, remove large number soil outside the site. Thanks to this quality, installing this type of foundation is a very economical choice. The main disadvantage will be the impossibility of equipping a basement or underground for utilities. In this case, the base of the building is covered with decorative materials.

Another advantage of piles is the possibility of using them in wetlands. Even if the groundwater level is located close to the ground surface, the supports provide the necessary load-bearing capacity.

The next option is tape. It can be made monolithic or from blocks. The second option is rational to use for mass construction. Strip foundations are:

recessed (for buildings with a basement, brick and concrete structures);
(for wooden and frame houses);
non-buried (technology of pouring foundations for small buildings on a solid foundation).

Before making a tape, it is worth checking the groundwater level and compliance with the rule that the sole cannot be closer than 50 cm to the groundwater horizon. Otherwise, there is a high probability of flooding of the basement, reducing the load-bearing capacity of the foundation and destruction of the materials of the supporting part of the building.

What to do with high groundwater level? If the structure is made independently from brick or stone, screw piles will not be suitable, and for bored piles it will be necessary to lower the water level. An excellent option would be filling. In this case, a non-recessed or slightly recessed base is made. The thickness of the slab is determined depending on the load, on average 300-400 mm.

How to pour a foundation for a house

Monolithic foundation type is the best option for private housing construction. In this case, laying allows you to significantly save on transportation and installation of structures. There is no need to hire a crane to install elements in the designed position or a KamAZ truck to transport concrete blocks and slabs.

Monolithic foundations can be made from factory-made concrete or you can mix the solution yourself using a concrete mixer. The first option is recommended. The fact is that it is very difficult to strictly observe the proportions of the composition in artisanal conditions. For factory-mixed concrete, such a guarantor will be a passport, which indicates the verified indicators of the material.

To make the material yourself, you will need to prepare clean water, cement, sand and crushed stone (or gravel). They are mixed with each other strictly observing proportions, which depend on what grade of concrete needs to be obtained. If you add a little more sand or crushed stone to the composition than required, the strength of the supporting part of the building will suffer.

To properly pour the foundation, you need to familiarize yourself with the basic rules of concreting:

Concrete must be poured in one go at time intervals of up to 1.5 hours. If you take long breaks in work, the solution sets and concreting seams are formed, which weaken the structure. The technology allows making horizontal seams if absolutely necessary. It is unacceptable to install vertical seams on a monolithic foundation, since in this case the support of the house will not be able to resist soil deformations.
The class of concrete is chosen depending on the type of supporting part. For a columnar or pile foundation, class B 15 is sufficient. For tape, grades from B 15 to B 22.5 are needed. Construction of a house foundation using slab technology requires concrete grades B 22.5 or B 25.
After pouring, the material should gain strength. On average, this takes 28 days. Continue construction work It is possible after the structure reaches 70% brand strength.
It is better to carry out work in warm, dry weather. The ideal average daily temperature for concrete hardening is +25°C. At temperatures below +5°C the material practically does not harden. For normal hardening in this case, special additives and heating are used.
The concrete must be maintained within 1-2 weeks after pouring. It involves wetting the surface with water.
To mix the mixture yourself, you will need cement, sand, crushed stone (gravel) and clean water. The proportions depend on the strength class. The material is delivered from the factory by truck concrete mixer - it allows you to extend the life of the solution and deliver it over relatively long distances.

How to pour the foundation correctly? In general, work is performed in the following order:

installation of formwork and reinforcement cage;
laying waterproofing material in formwork;
pouring concrete;
its compaction by vibration or bayonet;
curing;
stripping works (if necessary).

To quickly complete the work, it is recommended to order a concrete pump together with a concrete mixer. Concrete manufacturers are usually willing to provide this technique. In this case, it is necessary to use a concrete mixture of grades P3 or P4 in terms of mobility. Otherwise, the equipment breaks down.

Step-by-step instructions for pouring a strip foundation

Concreting is considered using the example of a monolithic tape. To erect the supporting part of the structure, construction is necessary. To do this, use cast-offs and construction cord. You need to show the edges of the tape.

After marking, the soil is excavated. If there is no basement, it is enough to dig a trench. At its bottom you need to make a sand cushion. It performs several functions:

ground leveling;
prevention of frost heaving;

The edges of the trench must go exactly along the cord

The next stage is . For this purpose, the material included in the estimate is used: boards (removable type) or polystyrene foam (non-removable). The second option serves not only as a form for pouring concrete, but also as insulation of the underground part of the building. When installing the formwork, I raise the base to the desired height.

The reliability of any structure depends on the quality of the foundation. In today's review we will take a closer look at the classic and newest types for a private home. This information will help you choose the optimal design based on your individual requirements. Step-by-step instructions will be useful for doing the work yourself.

Read in the article

Purpose of the foundation for a private house, determination of the main criteria

This part of the structure must ensure the stability of the entire structure throughout long term services. Most often, installation with a recess is used, so the increased complexity of repair operations is understandable. It is not difficult to immediately determine two main criteria: reliability and durability.

The following facts will help clarify the requirements for the foundation design for a house:

When choosing suitable technical characteristics, one should take into account the geological characteristics of the land plot, groundwater level, freezing in winter.
It is necessary to prevent the penetration of moisture from the soil into the walls, interfloor.
It is necessary to think about the functioning of other systems, input utility networks, installation and , technological equipment.
For a correct comparison of materials, the cost of the purchase itself, transport and installation operations are checked.

Important! Even in such relatively simple situations, accurate calculations are necessary. It will help ensure a sufficient level of safety during operation.

Types of foundations used in construction - analysis of advantages and disadvantages

Tape

Monolithic is used quite often. It is created directly on construction site. As is clear from the diagram, there is no need to carefully level the surface. Taking into account the specifics of the project, it is permissible to make individual edits. allows you to increase strength. It is necessary to remember temperature restrictions when pouring concrete. You will have to wait until the mixture hardens. These features slightly increase the construction time of the structure.

For your information! The use of rubble concrete mixture will save money. Gravel, boulders, and other cheap components are added to it.

You can speed up the work if you use brick or standard reinforced concrete blocks. In the latter option, the weight of the individual elements is too large to require manual labor. There is a need to rent a crane, which increases.

The figure shows typical components of a strip structure. Before pouring the mixture (3), a backfill of sand (4) is made in the trench. The number “9” indicates the recommended level of soil freezing. The relevant data can be obtained from your local architectural office. A concrete blind area (8), made at an angle from the building, will prevent the accumulation of water. Between the foundation and the wall (1) there is a layer of 1-2 sheets of roofing felt. In the basement, the soil (5) is compacted, the floor (6) and wall (7) are covered with sand. The last element is required for .

Foundation on stilts for a private house

The simplest situation is shown in Fig. "A". The pile is driven to the level of solid soil, which allows maintaining the stability of the structure as a whole. The upper parts of the supports are connected with a special element. Examples “b” and “c” demonstrate the possibilities of installation in quicksand, loam, sand, and other soft soils.

Such equipment creates noise and strong vibrations. Rent is expensive. Instead, indentation can be used using specialized equipment. Printing technology is also suitable. It consists of several stages. First, a hole is created with a drill. Next, the reinforcement is installed and poured.

Timber is used in the construction of light frame and wooden structures. Other options are suitable for building the foundation of a private house made of brick.

An additional advantage is the ability to perform high-quality installation in a small area, with a minimum amount of excavation work. However, for the sake of objectivity, we must remember the increased total cost of reproducing individual technologies in this category.

Related article:

This technology is used to speed up the construction of not too heavy buildings and other architectural structures. In the article you will find step by step instructions erection of the structure and useful tips specialists.

Columnar

Non-buried structures are used in the construction of bathhouses, gazebos, and garages. They are installed on compacted sand. For heavier structures, stone and reinforced concrete are used instead of standard blocks. Lightweight supports are made from.

In the buried version, steel pipes with and without fillers are used. This solution is suitable for quick installation of fences. This implies limited loads during operation.

Slab foundation for a private house

A properly designed monolithic base with reinforcement will withstand significant loads without damage. It can be installed in areas with high groundwater levels. This solution is used to eliminate the negative impact of heaving forces in winter. It is suitable for construction on sandy and other weak supports.

A significant disadvantage of a slab foundation for a private house is its high cost. As in the case of other reinforced concrete structures, when choosing this option, it is necessary to accurately plan the appropriate time for the work. When the air temperature drops below zero, special compensation additives are used. It is imperative to meet the standard period of product readiness, taking into account the thickness, grade of concrete and other parameters. In large slabs, special expansion joints are created that prevent cracks from occurring.

How to choose the right type of foundation for a private house?

For a correct determination, it is not enough to know what foundations there are. It is necessary to combine the above information with the distinctive parameters of your own project:

An accurate calculation assumes the total load. It includes weight building structures, equipment, technological equipment.
The terrain of the site is clarified and, if necessary, earthworks are added to the plan.
They check the geological structure, levels of freezing and groundwater, the presence of underground gas and other utility networks.
If a basement is present/absent, appropriate adjustments are made in the design documentation. The main attention is paid to issues of heat and.
Separately study the features of the main building materials, which are supposed to be used when constructing the foundation for a private house.
An acceptable period of time before major repairs is established.

Analysis of soil and hydrological conditions at the site

You can do the check yourself. To do this, they dig holes on the territory of the site in required quantity to a depth in accordance with the parameters of the future foundation. Particular attention is paid to places with high groundwater levels. The corresponding areas are first determined by indirect signs (specific plants, accumulations of dew and fog).

For your information! During the inspection, it is necessary to find out the reasons for the formation of dips on the surface, cracks on pedestrian paths and roadways. These defects indicate a heterogeneous soil composition.

Calculation of the required laying depth and other parameters of the foundation design

To calculate this defining parameter, it is necessary to check the design features of the foundation for a private house, groundwater and freezing levels, and the geological section. A separate calculation is made for each of the listed points. The greatest depth is left in the project.

To simplify solving the problem, use specialized calculator programs. Accurate results can be obtained if you place an appropriate order in a specialized design office. As an example, we present the main stages of a typical algorithm for calculating the depth of a strip-type foundation under.

Calculate the standard depth (Ng) using the formula:

Ng = Pk × Тп , Where

PC – soil coefficient (for sand the value is 0.3);
Tp – temperature indicator, which is equal to the square root of all negative average monthly temperatures for the year (for the Moscow region - 4.77).

For example, for the Moscow region: Ng = 0.3 × 4.77 = 1.43 m .

The resulting value is multiplied by another tabular coefficient, which is calculated taking into account the conditions inside the rooms and architectural features. When maintaining a temperature of +20°C in the room adjacent to the outer part of the foundation, a value of 0.4 is taken. The freezing level is determined accordingly: Pack = 1.43 × 0.4 = 1.03 m . It is recommended to install the tape structure 0.15-0.2 m lower.

To ensure a stable position, it is necessary to ensure that the area of the foundation support area (Pf), multiplied by the bearing capacity (Nc) of a certain soil, is greater total weight buildings (S) together with equipment: Pf × Ns > Sun .

The right choice of foundation for a house under construction will help create a reliable, stable, durable building that will serve for many generations. There are several basic designs from which you need to determine the best option. This can be done taking into account certain factors, including the weight of the house being built, the type of soil, the presence or absence of basements and other criteria.

The main function of any foundation is to become a reliable foundation for the building erected on it, and this is a rather difficult task. Therefore, when choosing a type, it is better to consult with professionals. Among the factors influencing the choice the right type foundation, the characteristics of the soil on which the house will be built are decisive. To do this, you will need to conduct a geological survey of the site to obtain the following data:

type of soil and its basic physical and chemical characteristics (density, composition, humidity, etc.);
freezing depth in a given area;
availability of groundwater and its level;
relief features.

During the study, several main types of soil are identified, which require their own version of the base with special technical characteristics:

Weak. Sandy soils, clayey, silty soils, peat bogs. They have a reduced load-bearing capacity and are deformed during operation. Clay soils, in addition, are susceptible to heaving.
Rocky. This is a reliable foundation consisting of dense rocks that does not require unnecessary work on preparing the foundation.
Dense. It is quite easy to dig a trench in them, but due to their resistance to loads and heaving, they do not require massive foundations.

Particular attention should be paid to groundwater, as it can undermine the foundation and warp the building. Therefore, at high groundwater levels, waterproofing is very important. In areas with harsh climates, it is imperative to take into account the fact that the base must provide a sufficient level of thermal insulation.

The main criteria for choosing the type of foundation include:

sufficient load-bearing capacity;
high-quality thermal insulation between the floor and the ground;
strength and durability of materials ensuring long-term operation of buildings;
possibility of building dry basements and garages.

Types of bases

Structurally, there are several types of foundations for a private house. The most commonly used designs are:

Tape is a classic option.
Pile - for difficult terrain and soils.
Slab - used in harsh climates on swampy or wet soils.

Each of these types has its own advantages, so make an informed decision when choosing.

Tape

This type of foundation is used most often and is suitable for houses made of wood, brick, foam or gas blocks or stone. This is a rather expensive option, but on dense soil it is the most reliable basis. It is recommended to build such foundations on level areas; a slight slope is allowed.

The depth of the laying and the thickness of the strip base depend on the material from which the walls will be built, their thickness and the number of floors in the building. The main advantage of this type is its high load-bearing capacity. When laying it, the base must be below the freezing point of the soil in the given area. The exception is light wooden buildings, for which a shallow foundation is suitable.

The disadvantage of a strip base is poor waterproofing. To prevent the walls from becoming damp, its upper part is covered with roofing felt or other waterproofing materials, covered with bitumen, rubber compounds, etc. To protect against water, you will need a reliable wide blind area.

Technologically, monolithic and prefabricated strip foundations are distinguished. The monolithic version is poured into pre-prepared formwork, in which the reinforcement cage is previously installed.

The prefabricated strip foundation is made from FBS blocks. This technology is used when it is not cost-effective to produce or transport fresh concrete mix, in unfavorable climates, etc. The advantages of this type include high speed of construction, due to this it is much cheaper. But working with it requires professional skills, so this foundation is more complex. When installing FBS, cranes or other loading equipment will be required.

A correctly installed prefabricated foundation is not inferior in strength to a monolithic one.

Pile

Pile-type foundations are used in places with complex terrain, heaving soils, swampy, and sandy soils. They resort to it when it is not possible to make a high-quality strip base. To save money, it is used as a foundation for light buildings on any soil.

The main structural elements are screw steel piles with anti-corrosion treatment, which are connected by a concrete grillage. Therefore, it is necessary to pay attention to the quality of piles special attention. The advantages of pile foundations include:

the possibility of constructing a foundation in any type of soil, except rocky, due to the immersion of piles to a depth of up to 35 meters;
this technology allows you to equip large premises such as an underground garage or cellar;
treated piles will serve as reliable support for at least 100 years.

This technology also has its disadvantages:

the relatively small load-bearing capacity does not allow the construction of brick buildings, stone, or monolithic concrete;
buildings on a pile foundation require additional thermal and waterproofing.

In a columnar foundation, steel piles are replaced with brick or concrete columns with reinforcing mesh. They are buried below the freezing level of the ground. This type allows you to save on materials, but is not suitable for permanent buildings made of brick, concrete or stone.

Slab

A slab foundation, also called a floating foundation, is used to create a reliable foundation on difficult soils. It is used in construction on:

heaving soils;
in wetlands;
at high groundwater level.

At the heart of such a base is a reinforced concrete slab, laid behind a specially prepared cushion. Important design feature is the uniform arrangement of the steel reinforcement frame throughout the slab. The result is an exceptionally rigid and durable foundation.

This type is excellent for constructing a plinth; it has good hydro- and thermal insulation due to insulation; it allows you to build houses in areas with difficult climates, on swampy, loose soils.

During construction, a foundation pit is dug that matches the area and shape of the future building. The soil is carefully compacted and a sand and gravel cushion is made on it. Several layers of different fractions are separated with geotextiles, after which formwork is made and the reinforcement frame is welded. After this, the slab is poured, and the places where the walls will be built are marked with a monolithic tape. The advantages of such designs include:

stability and absence of deformation;
increased strength due to the solidity and strength of the reinforcement;
resistance to adverse conditions, humidity and temperature changes;
possibility of construction on moving soils;
excellent waterproofing.

The disadvantages of a slab foundation include its high cost due to the large volume of concrete and continuous reinforcement.

Comparison of characteristics

The foundation is the basis of any home, and the durability and comfort of the future building depends on its strength and stability. Some types of foundations are suitable for houses made of timber, and for brick houses two-story houses– others, with increased load-bearing capacity. To make a choice, you need to compare the main characteristics and properties of these structures, summarized in the table:

Characteristic	Tape	Pile-screw	Slab
Carrying out excavation work before construction	Yes	No	yes, but less than in tape
Construction period	4-6 weeks	1-3 days	4-6 weeks
Construction on difficult soils and terrain without additional work	No	Yes	Yes
The ability to immediately fully load the foundation and mount the house	No	Yes	No
Limiting construction to warm seasons	Yes	No	Yes
Possibility of constructing basements and ground floors	Yes	Additional technical solution required	Only for ground floors

Thus, when determining what kind of foundation is needed to build a house made of foam blocks, it is necessary to determine its weight, good option there will be a strip foundation or slab if construction is carried out on unstable soils. In this case, on dense or rocky soil, a shallow concrete strip is suitable. But for a house made of foam concrete blocks 2 floors high, they require a strip or slab foundation buried below the freezing level of the soil.

A strip shallow foundation is best suited for frame houses with low mass. Its strength is quite enough to ensure the stability of the building. The same can be said for houses made of timber with a wall thickness of 30 cm. The light and durable construction of such a house has increased thermal insulation. On complex heaving, swampy or unstable soils, it is better to erect such buildings on pile foundations, buried to dense layers, which will ensure stability.

When deciding which foundation is best suited for a log house, you need to pay attention not to the strip and pile type; slab structures are not very suitable for wooden buildings. The depth of the ribbon type depends on the number of storeys of the building; for one-story buildings, a shallow depth is sufficient.

The cheapest foundation is a pile foundation, which requires the least amount of materials. Strong metal piles are connected by a not too massive concrete grillage. A strip foundation requires much more materials; if the freezing depth of the soil is 1 m, then it will have to be buried by 1.2 m; with a width of 0.5 m, 0.6 cubic meters will be required for each linear meter. meter of concrete, with the appropriate amount of reinforcement. A slab foundation will require an even larger amount of cement, since, despite its relatively small thickness, the monolith is laid under the entire house. However, the base does not require a screed under the floor, as a result it saves significant money compared to the tape type.

Before choosing a foundation for a house, it is better to study the advice of professional experts. They will help you avoid many problems and get a reliable basis without incurring unnecessary costs.

On dense soils, strip structures buried below the freezing mark or shallow-buried options are more often used. These bases are suitable for buildings made of any material - brick, concrete, stone, wood.

When choosing which type is best to use on clay soils prone to swelling, experts advise piles that will not require additional arrangement. If the belt type is used on clay soil, it is necessary to take care of a sand cushion of sufficient thickness.

For buildings on sites in marshy areas, a slab option is used. The same type is well suited in areas where groundwater is close to the surface. This type of base will provide high-quality waterproofing and evenly distribute the weight of the house onto the ground.

Conclusion

Choosing the optimal foundation design is the key to the success of the entire construction. This choice should be based on an accurate calculation based on an assessment of the condition of the soil, the materials used for the construction of the building, and the owner’s requirements.

Shallow foundations are suitable for buildings made of wood or frame construction. They do not exert much pressure on the ground surface, ensuring the stability of the building throughout its service life. They can be strip, pile or slab type. The main advantage of such bases is their low price.

Deep foundations below the soil freezing level will be required for the construction of multi-story buildings, houses made of concrete and brick. They are characterized by increased stability and resist subsidence and cracking of walls. The type of foundation must be selected according to geological studies. For dense soils, the strip type is suitable; on heaving soils, it is better to choose pile structures; for high humidity and looseness, the use of a slab would be a justified solution.

For strips, slabs or grillages, it is better to use concrete of at least grade M300 and reinforce the structures with a welded steel frame. Pile foundations made of concrete or steel supports connected by a grillage.

If the owner does not have sufficient experience and knowledge, it makes sense to contact construction company, where experts will suggest the right solution. It will be reflected in the project according to which the building will be built.