Which foundation for a house is better: types and purposes

How to choose the right foundation for a house? Perhaps this is one of the first questions that an independent developer faces. The reliability and service life of the building depend on the correct answer to this question, because the foundation is the foundation. And if this foundation is chosen and made incorrectly, then it will not be able to support the weight of the house.

The consequences, unfortunately, can be very sad. From constantly occurring mesh cracks in the finish, to the appearance of large through cracks and destruction of walls. The house can also tilt like the famous Leaning Tower of Pisa.

We will tell you what types of foundations there are for a private house and for what soils and houses they are best suited.

General information about foundations

If you start building walls directly on the ground, then most likely, even at the construction stage, the brick structures will crack and fall apart, and the wooden or frame structures will tilt and warp. This will happen due to the fact that the soil underneath will subside. The only exceptions will be walls built on rocks.

Houses made of heavy materials such as brick, cinder block or reinforced concrete require soil studies and the correct choice of foundation. Don't take risks and build a foundation at random

The fact is that the soil on the surface has a low bearing capacity, which is not enough to support the weight of a residential building. At the same time, in the overwhelming majority of cases, the deeper into the ground, the greater its bearing capacity becomes.

The main task, so to speak, the essence of any foundation, is precisely to transfer the weight of the building to those layers of soil that can support it. To do this, depending on the type of soil, a suitable foundation depth is selected, as well as its type: strip, pile, columnar or slab

In addition to the load-bearing characteristics, the soil has three more parameters that determine which foundation to build for the house:

• soil freezing depth;
• the upper mark (level) of groundwater;
• heaving of the soil (increase in volume when freezing).

Heaving soils are the worst for construction. Such soils absorb and retain moisture, which increases in size when it freezes in winter. At the same time, the soil bulges upward with enormous force, pushing out and breaking any buildings installed on it. To avoid such consequences, the foundation must rest on layers located below the freezing depth, which is different for each region. Here lies the answer to the question of how deep the foundation should be for a house. The foundation must be buried below the frost depth.

The map of soil freezing depth clearly shows how much this indicator differs in different regions of Russia.
The more the soil can freeze, the deeper the foundation must be laid. In addition to freezing, the choice of foundation is also influenced by the soil’s tendency to heave when frozen. The higher this indicator, the more responsible you need to approach the selection and construction of the foundation. The presence of groundwater aggravates the situation with heaving, and also limits the use of columnar and strip foundations, making the construction of a basement expensive or impossible. In such conditions, slab or pile foundations look more appropriate.

By the way, if before building a house you make a well on the site for overhead water, then the depth of groundwater can be determined with very high accuracy by the water level in it.

Another option to avoid the harmful effects of soil expansion is to take measures against heaving, for example, insulating the blind area and basement. This works great with shallow strip foundations.

In order to choose the right foundation for a house and not overpay for excessive strength, it is necessary to take into account the characteristics of the soil in the construction area.

The best solution for building a reliable foundation is to study the soil and develop a project based on it in a specialized organization. This will save you from mistakes and excessive costs.

Factors influencing the choice of foundation for a house

The characteristics of the soil foundation are determined by what the groundwater level is, how deep the soil freezes and what its composition is.

1. Composition of the soil base

Depending on the bearing capacity, there are 3 types of soils. Next, we will look at the features of each of them.

• Weak soil foundations
  Weak soil foundations include peaty, clayey, and sandy soils. For example, it is not recommended to build houses on peat bogs, because such a soil foundation is unreliable. If the building stands on clay soil, you may encounter heaving, when the volume of the soil increases greatly due to saturation with moisture.

  As a result, the foundation will be pushed out from under the ground. The same thing happens to the foundation of a house when the soil freezes.

  Read also:  An option for a durable and inexpensive foundation for a house is a columnar foundation

  Since weak sandy soils have low bearing capacity, the structure will sag and the foundation will be destroyed. If you plan to build a house on such soil, you should lay a pile foundation with a grillage or monolithic reinforced concrete slabs on or without piles.

• Rocky foundations (rocky soils)
  This type of foundation is considered the most reliable. In this case, the foundation can be monolithic strip or prefabricated reinforced concrete. You can also make a columnar support with a grillage.
• Dense soils
  Dense soils are formed from cohesive rocks that can withstand high loads and are resistant to heaving. What kind of house foundation is best in this case? The best option is a strip monolithic or prefabricated reinforced concrete base. In addition, columnar foundation supports can be used. Any type of foundation can be built on dense soil.

Strip foundation for a house

What is strip foundation?

This is the most popular foundation for private housing construction today. A strip foundation is a strip poured from concrete or assembled from blocks, the shape repeating the location of the load-bearing walls of the house. In fact, a tape foundation is the same wall, only located underground and has high strength and resistance to moisture.

Monolithic (left) and prefabricated (right) foundations are made using different technologies, but both are of the strip type. The shape of the monolithic base is determined by the pre-set formwork into which concrete is poured. The contours of the prefabricated tape are set directly when installing the blocks

The sole of the tape should rest on soils lying below the freezing depth, which can reach 0.8-2.4 meters and depends on the climatic conditions of the region, as we discussed above. The exception is shallow foundations, which are discussed below.

What is the foundation sole?

The sole is the lowest part of a strip or column foundation, which rests on dense layers of soil. It is the sole that is responsible for transferring the main load from the weight of the building to the ground. The weaker the soil, the wider the sole needs to be made, thus increasing the support area. In this case, the tape itself can be significantly narrower than the lower support, which greatly saves concrete consumption.

The width of the foundation is selected according to the characteristics of the soil, the weight of the house and the features of its design. The lower the bearing capacity of the soil, the wider the tape or its base should be. This is necessary to evenly transfer the load to the ground and eliminate uneven subsidence.

Also, the width of the tape increases with a large mass of the house to give it the necessary strength. For example, for a two-story brick house with reinforced concrete floors, the tape should be wider than for a one-story house made of timber. The width of the tape is also increased if it is necessary to cladding the house with brick.

Structurally, strip foundations are made of two types:

• Monolithic;
• Made.

Below we will tell you what types of strip foundations there are for a house.

Monolithic foundation tape

What is a monolithic foundation?

This is a strip foundation made by simultaneously pouring concrete into pre-set formwork that follows the shape of the building and load-bearing partitions. Due to the fact that all the concrete is poured at once, after hardening it turns into a single strong structure - a monolith.

A strip foundation made of monolithic reinforced concrete has increased strength and is able to withstand the weight of a building made of any material. When assembling the formwork for pouring the foundation, the most important thing is to ensure its strength. To do this, the formwork is fixed to the ground as firmly as possible, and is also abundantly tightened with pins. If the strength is not enough, then the heavy concrete will simply crush the formwork and leak out. The higher the foundation, the stronger the formwork should be

A monolithic foundation is the strongest type of foundation and successfully withstands all impacts placed on it. When using the appropriate grade of concrete, the monolith is very resistant to water.

The main stages of pouring a monolithic foundation are as follows:

• Preparation of a pit with mandatory vibration compaction of the soil;
• Carrying out markings for the foundation;
• Installation of formwork;
• Laying and tying of reinforcement;
• Pouring concrete.

The formwork can be either removable or permanent, the latter acting as insulation for the foundation.

Reinforcement is installed into the assembled formwork to give the structure bending strength. Metal reinforcement is used, sometimes fiberglass, but it is better to give preference to the former - it stretches less under load. The main reinforcement should be on the top and bottom rows. They are the ones who experience the maximum load if the soil shrinks or heaves.

You can quickly calculate the volume of concrete, reinforcement and formwork for pouring a strip foundation using our online calculator

Concrete is poured without interruption; this is the only way to obtain a monolith. The concrete must be vibrated to release air bubbles. This will increase strength and eliminate pores in the concrete.

Advantages and disadvantages of a monolithic strip foundation:

* Suitable for any home, if soil permits

*High construction speed

* Absolutely any foundation shape and tape width

* High load-bearing capacity, which can be easily adjusted by increasing the width of the sole without changing the width of the tape itself

* Depending on the depth of the foundation, when pouring the foundation, you immediately get a basement, semi-basement or basement

* When properly waterproofed, completely waterproof

*May not be suitable for weak or uneven soils with a heavy house

* At high groundwater levels, 100% waterproofing is required, the achievement of which is problematic and expensive

* If made unprofessionally, there is a risk of destruction or serious deformation of the formwork with leakage of concrete

* For light-weight wooden houses and frames, it is more expensive than screw piles

In general, a monolithic foundation is a universal solution for construction: a monolithic strip is suitable for most soils and buildings.

Prefabricated strip foundation

What is a precast concrete foundation?

Prefabricated strip foundations are ready-made FBS or FBP foundation blocks, which are stacked on top of each other in the form of a strip in a pre-prepared foundation pit.

The main difference from a monolith is the lack of unity of design. Here it consists of a set of cubes. The width of the blocks is from 200 to 600 mm in increments of 100 mm. Height from 280 to 580 mm in increments of 100 mm. Lengths 580, 1180, 1780 and 2380 mm. There are other block sizes, but they are less common.

Due to the availability of blocks of various sizes, a prefabricated foundation can be given almost any shape. Such a foundation will have to be installed using a crane. Blocks made at the factory from graded concrete themselves are not afraid of moderately damp soil, and coating waterproofing only enhances this effect for a while. To make a prefabricated foundation fully waterproof, expensive comprehensive waterproofing is required.

Typically, prefabricated foundations are used on stable soils, so they are not reinforced. But if desired, you can lay reinforcement when pouring the base of the foundation, between rows of blocks, or install an armored belt on top of the blocks.

The indisputable advantage of a prefabricated foundation is the speed of construction and the ability to load it almost immediately after installation. That is, construction is going much faster

To carry out installation work on the assembly, you will need a crane or manipulator, since the foundation blocks cannot be lifted manually.

Remember above we told you what the base of a foundation is? So, to increase the load-bearing capacity of the prefabricated tape, you can use special wide FL blocks for the sole or fill in a wide reinforced monolithic sole.

The use of trapezoidal FL blocks makes it possible to double the area of ​​foundation support and reduce the load on the ground. At the same time, there is no need to make the entire foundation wide, which significantly saves the budget

Pros and cons of a prefabricated foundation:

* Speed ​​of construction

* No heavy work during self-construction (no pouring or vibrating of concrete, no risk of destruction or deformation of the formwork)

*High load-bearing capacity

* Factory-made blocks are guaranteed to have the correct reinforcement and the required grade of concrete

* High price

* The need to use special equipment that cannot go everywhere

* Uneven shrinkage in poor soils and lack of reinforced belts

The prefabricated tape is suitable for good soils and all types of buildings, and is also quick to install.

As you can see, the main factor influencing which foundation is better to make, monoline or prefabricated, is soil stability.

Types of bases

Correct analysis of the soil composition allows you to make the optimal choice of construction foundation. The most common varieties are:

• ribbon – is a concrete frame in the form of a ribbon passing under all load-bearing structures;
• slab - looks like a monolithic reinforced slab laid on the ground;
• columnar - most often used for wooden buildings and consists of pillars sunk into the ground, which can be of a collapsible system;
• pile - uses various types of piles that provide a durable system.

During the operation of any building, the soil is subjected to high loads. The most durable in this regard is the strip type of base, which is a reinforced concrete strip that takes on all the loads. On stable soils there is no need to deepen it. If your site is unstable or too wet, experts advise building on a slab option. Before choosing the right foundation for your house, you should consider the following factors:

• the foundation must provide sufficient strength for your structure with the possibility of expansion;
• at the same time, it must minimize heat transfer from the room to the ground and vice versa;
• its service life should be higher than that of walls and other structures, since it is not always possible to repair it;
• it is necessary to provide for the possibility of creating cellars, garages and various utility rooms;

For private construction, efficiency is important, but loss of quality is unacceptable. Each of the considered types of bases has its own advantages and disadvantages. It is impossible to call any model the best, because they are all used for different situations. Let's take a closer look at the most commonly used types.

Strip foundation

It is distinguished by its versatility. It can be used both for frame buildings and for permanent stone structures. The only limitation is the possibility of erecting it on dense rocks without severe heaving. At the same time, the area should have fairly flat terrain. The main advantages of this type are:

• high strength, able to withstand brick buildings;
• Great opportunities for using interior spaces.

Disadvantages include a low level of heat resistance and moisture resistance. Therefore, it is not recommended to install it in areas with high humidity. This base is installed around the perimeter of the entire house. It is also necessary under internal load-bearing walls. Its construction is accompanied by a lot of earthwork and most often requires the installation of formwork. Moreover, this type of foundation is considered one of the simplest to construct. With this foundation, you can easily create high-quality and spacious basements. At the same time, the concrete strips themselves serve as walls in the lower rooms. However, during construction it is necessary to take into account the groundwater level.

The service life of the tape type depends on the material from which they are built. So, brick structures last 40-50 years, concrete ones 60-80. If they are made of monolithic concrete, they can successfully perform their functions for several centuries. It is worth noting that longevity also depends on the quality of raw materials, soil conditions and other factors. Such foundations can be monolithic, prefabricated or combined. The first type is made directly on site by pouring concrete. To increase strength they are reinforced. The prefabricated one is assembled from individual reinforced concrete blocks, which are then secured to each other using concrete and reinforcement. Depending on the material used, such bases are divided into:

• rubble - made from large stones of natural origin;
• rubble concrete - smaller material filled with concrete is used;
• brick - is a regular masonry made of moisture-resistant brick;
• concrete - poured into a pre-prepared form.

Slab foundation

This is one of the most expensive types of foundation. It allows you to build reliable and durable buildings. The basis is a monolithic reinforced slab, which is laid on a sand and gravel bed. To obtain the necessary properties, a combination of technologies is often used and slab-strip and slab-pile constructions are erected.

Sometimes, to simplify construction, several slabs are used instead of one. However, after laying them you will still need a strong cement screed on the surface. The best foundation for a house of this type is a solid monolithic surface.

When deeply buried, this variety can serve as a floor on the basement floor. To ensure the required strength, reinforcement is carried out over the entire area of ​​the reinforced concrete product. This protects against cracks, even with poor-quality soil. The main advantages of using the stove are:

• possibility of operation under any load;
• There are practically no restrictions regarding soil;
• good thermal insulation performance;
• moisture resistance.

The disadvantages are:

• the need for a perfectly flat surface;
• high price;
• If the location is shallow, there is no possibility of constructing underground premises.

To confirm the service life of a monolithic foundation, you can refer to history. Egyptian pyramids, installed on a similar foundation, have been standing for several millennia. This is the most durable material. However, when using slabs it is not always possible to achieve such results. Complex structures require complex load calculations. When used on problematic soils, the slightest imperfections can affect the durability of the product.

It is worth noting that slab varieties are able to compensate for significant horizontal and vertical soil vibrations. That is why it is often used in bulk, heaving and permanently frozen layers of earth. It also protects the building from groundwater, but there must be a well-thought-out drainage system, hydro- and thermal insulation.

Pile foundation

In this type, the main supporting element is piles. They evenly distribute the load from the building and are not afraid of uneven shrinkage, to which tape is very sensitive. This type is the only one possible for use in some types of complex and moving soils. In addition to ensuring the stability of buildings, pile structures can strengthen the soil. There are several types that are used depending on the requirements for future construction.

Screw piles are suitable for low-rise buildings on low-moving land. Also, to use them, groundwater must lie at a depth of more than 3 meters. They are a metal pipe with a drill at the end. Therefore, when choosing them, you should pay attention to the quality of the metal. It should be remembered that even corrosion-resistant metal products lose their properties over time if they are in an aggressive environment. Among the obvious advantages is the possibility of installing such products without the use of special equipment.

Reinforced concrete piles are highly durable structures that are resistant to aggressive environments. They are able to withstand enormous loads for a long time without changing their properties. At the same time, thanks to different types of concrete and reinforcement, it is possible to create reinforced concrete elements with different characteristics.

Bored products are considered the most reliable and can successfully withstand both vertical and horizontal loads. However, they are very expensive and their use in low-rise construction is not always economically justified. Working with such structures requires the use of a large amount of complex equipment. You will also need a lot of high-quality concrete and reinforcement. The choice of foundation type for a pile-type house is based on careful survey work. Its main advantages are:

• high resistance to various mechanical influences;
• resistance to aggressive substances;
• long service life;
• a large margin of safety, which is especially important for private housing construction, when residents are constantly expanding their buildings.

Among the shortcomings are noted:

• high installation complexity;
• during installation, neighboring buildings may be damaged;
• high price.

However, despite all its shortcomings, this type is often used in both individual and multi-apartment construction.

Columnar foundation

It consists of pillars installed according to the calculations carried out. It is suitable for small buildings not exceeding 2 floors in height. The construction of such a foundation does not require earthworks, and its cost is the lowest. However, this type should not be used in the following cases:

• in areas with moving soil in a horizontal plane or high levels of humidity;
• if you are planning to build a large house with brick or reinforced concrete walls;
• with a significant difference in height.

The columnar foundation is made of wood, brick, concrete and other materials. The service life of supporting structures depends on the choice of raw materials. Even for treated wood, the service life does not exceed 30 years. However, reinforced concrete pillars have an almost unlimited service life.

To increase durability, products are treated with various compounds that protect against moisture, rodents and other factors. For wooden supports, you should select durable wood. For a long time, rubble stone has been used as a material for the construction of columns, which has a long service life. This type is repairable and, if necessary, you can replace the damaged part with minimal labor costs. Depending on the depth of the pillars, such a foundation is divided into:

• not buried;
• shallow;
• buried.

Shallow strip foundation

Let's figure out what a shallow strip foundation is?

This foundation is a subtype of the strip foundation and can be either monolithic or prefabricated.

Its main difference is that the base of the foundation is located above the freezing point of the soil. The shallow belt is mounted on sand and gravel preparation at a depth of only a few tens of centimeters

Such foundations are attractive due to their price, which is several times lower than their counterparts, buried to a depth of 2 meters. However, this also causes its main drawback. If soil heaving occurs under the foundation, this will lead to a violation of its geometry and integrity. The same fate will befall the walls of the house.

Due to the shallow depth of installation, as well as the small volume of excavation and concrete work, a shallow strip foundation is simple and quick to install. However, in most cases, the surface location requires taking measures against soil heaving such as insulation and drainage. It is also possible to construct such a foundation with complete replacement of heaving soils underneath with non-heaving soils up to the freezing depth

A shallow foundation performs well in warm areas where the soil does not freeze, or on non-heaving soils (rock, hard clay, sand). In areas with frozen soil, a shallow foundation requires mandatory drainage, as well as insulation and the presence of an insulated blind area. Thermal insulation prevents the soil under the foundation from freezing and pushing it upward.

Pros and cons of a shallow strip foundation:

* Low construction cost

* Possibility of self-production

* Not suitable for all types of soil; on heaving soils it requires mandatory insulation
* Even with insulation, the soil under a house left without heating for the winter can freeze and damage the structure

* In most cases, low load-bearing capacity due to reliance on the upper weak layers of soil

Shallow tape is suitable for not very heavy houses. These can be one or two-story wooden or frame buildings, as well as houses made of foam blocks, wood concrete and similar materials. For the construction of heavy brick buildings with reinforced concrete floors, this foundation is not always suitable.

Conclusions. On foundations with good load-bearing capacity, a strip foundation is suitable for any home. If the groundwater is located high, the foundation will require reliable waterproofing, and therefore will cost more.

For light houses it is cheaper to make a pile foundation rather than a strip foundation. Shallow foundations are cheaper, but are only suitable for houses with low mass and require insulation on heaving soils. If you need a house with a basement, then tape is an ideal option.

You can quickly calculate the volume of concrete, reinforcement and formwork for pouring a shallow strip foundation using our online calculator

Which foundation is better for a house made of timber?

Nowadays, the construction of houses made of wood is becoming increasingly popular. This is explained by the fact that the latest wood processing technologies are used. For example, it will be possible to build high-quality walls from profiled timber quite quickly. Such a house will be light and resistant to deformation. Thanks to these properties of the wood used, the requirements for the foundation are simplified. Let's take a closer look at what is the best foundation for a wooden house.

1. Pile This type of foundation has many advantages: it can be erected on any soil, and this will require a minimum of time and labor.
   However, it is worth noting that if you build a wooden house on stilts, you will have to spend a large sum. An alternative solution is screw piles; they are quite reliable and easy to install. Such a base can be used both on homogeneous soil and on loose soil. The project can be designed in such a way that the piles will support all the walls of the house or only the load-bearing ones. The installation of the structure is carried out in a short time. You will need construction equipment, but you can install the piles yourself, with the help of a group of builders.
2. Columnar
   Which foundation is better for a one-story house if your budget is limited and you need a solid foundation? The right solution is a columnar foundation, which is suitable for both residential buildings and outbuildings. The main thing is that the soil is stable and has a high bearing capacity.
3. Strip
   The strip foundation is ideal for buildings made of timber. It is made in the form of a concrete strip that fits into the base of the walls. This base is suitable for both a small house and a two-story cottage. Despite significant advantages, strip foundations have disadvantages. For example, high labor costs when working with soil (when it is necessary to equip a basement), as well as high costs for the purchase of material. This type of foundation can be built on dense soil.
4. Tiled
   In some cases, a strip base is not suitable. For example, due to the fact that the soil has insufficient bearing capacity. The only correct solution in such a situation is to pour a monolithic reinforced concrete slab. This base will be strong and highly stable. Among the main disadvantages are the high cost, large labor and time costs when creating a pit and moving earth.

   The plate weighs quite a lot, so it needs to be balanced. When the calculations are made incorrectly, the slab will hang on one side. In addition, it is unprofitable to use a monolithic base when constructing buildings made of timber. This option is suitable only if it is impossible to equip another type of foundation for technical reasons.

Which foundation for a house is better? To answer this question, it is necessary to take into account the difference in elevation in the house plan, the likelihood of shifts and landslides in the nearby area.

Taking into account the features of all the above reasons, it should be noted that:

• if the soil is clastic or rocky, the house must be built on a strip or columnar foundation (shallow or shallow);
• when the soil is sandy, the base should be columnar and shallow. If a basement is required, the foundation must be strip;
• if the soil is clayey, a columnar base is suitable, which is buried below the freezing level. A foundation on piles or a strip foundation is also suitable if you need to equip a basement;
• when the soil is weak, dusty or waterlogged, the base should be slab.

Note!

When a house is being built on a steep slope, the lateral pressure of the soil on the pillars and walls should be taken into account. Over time, soil (with the exception of rock) acts on the foundation in the same way as liquid, that is, it pushes out the buried foundation. And if the house is on a slope, it overturns. Therefore, in this case, the best option is screw piles, because they have a developed anchor part, the strapping is quite rigid, and the trunk is thin.

Pile foundation

What is a pile foundation?

This type of foundation is a set of piles screwed or driven into the ground (pile field), united at the top by a concrete, metal or wooden grillage. Walls are built on top of this grillage and the ceiling is installed.

Sometimes in everyday life you can come across the terms grillage or pile-grillage foundation. Let's figure out what we're talking about.

What is a grillage foundation? This is a foundation consisting of columns or piles (no matter what), which are connected from above into a single system by timber, a metal channel or a reinforced concrete belt. What is a pile-grillage foundation? This is a grillage foundation consisting of piles and a grillage. As you can see, these concepts are almost the same. Why do you need a grillage? You know that houses in most cases are built from piece materials (bricks, blocks, boards). To install wall materials, a flat surface is required, and piles sticking out of the ground are definitely not a surface. So you need a grillage to create a foundation for the masonry. In addition, the grillage connects all the piles to each other, making the base a single structure.

Foundation piles are reinforced concrete or metal pins that are driven or screwed into the ground. Bored piles are also used, where reinforcement is inserted into a pre-drilled hole in the ground and concrete is poured. It is the type of piles used that determines the types of pile foundation: screw, driven or drilled.

Driven and drilled piles are an excellent solution when strong layers of soil appear at great depths, and therefore construction of a belt is expensive and impractical. Screw piles are more often used for lightweight houses, so it is enough for them to be drilled with the screw part just below the soil freezing level

The length of the piles and, accordingly, the depth of their laying depends on the strength of the soil underlying the house and the weight of the building. The task of the pile is to overcome weak soils and, resting on strong layers, transfer the load from the structure to them.

Pile foundations can be effectively used in the following cases:

• Insufficient soil strength to support the weight of the building on a strip or slab. Or there is a high risk of uneven settlement when supporting the foundation on different soils at the same time;
• If it is impossible to build a belt due to high GWL (groundwater level);
• As a support under a tape or slab on poor soils;
• For light houses without a basement.

Pile grillage foundation, what is it from the developer’s point of view? This is an opportunity to make a reliable foundation on soft soils at minimal cost.

Depending on the load and soil characteristics, different piles are used. Below we will talk about the most common types of pile foundations.

Metal and concrete screw piles

Let's figure out what screw piles are. In fact, everything is simple - these are metal pipes or monolithic concrete rods, the front part of which is made in the form of a thread (screw).

Thanks to the presence of a screw, the rotating pile is screwed into the ground, plunging deeper and deeper. The process is similar to how a screw is screwed into wood.

Metal screw piles are most widespread in private construction

Structurally, it is a simple pipe with a diameter of 57 to 159 mm with a cone-shaped tip and blades located at an angle. The length of the pile is selected according to the type of soil and starts from 2 m. To install the piles, a recess is dug with a shovel. Then a pile is inserted into it and begins to rotate using a pipe. The work needs to be done by two people.

The operating principle of metal and concrete screw piles is the same. Metal products have greater elasticity, but are less resistant to corrosion, so during transportation and installation you should try not to damage the coating. Concrete piles do not rust, have greater compressive strength, but are also more fragile, so care must be taken when loading

The piles are twisted at the corners of buildings, as well as at certain intervals under all load-bearing walls. After screwing the piles, they are all cut off at the same level, and the heads are welded on top of them. Next, a beam is screwed onto the heads, on which the house is then assembled. Also, before installing the heads inside the piles, you can pour concrete, which will give them additional strength and protect them from internal corrosion.

The ability of the pile to transfer load to the ground is ensured by blades drilled into durable layers to a depth below the freezing point. Thanks to this, the pile foundation is not afraid of frost heaving. In addition, piles can be used at any water level, but the presence of water will accelerate metal corrosion.

Both concrete and metal piles can be driven into the ground either manually (left) or using machinery (right). The second method, although more expensive, will significantly save effort and time on building a foundation.

The undoubted advantage of this technology is the possibility of self-installation without the involvement of special equipment and concrete work. And the strength of the piles is enough to support wooden and frame houses. The main disadvantage is that the piles can only be driven into soft soils. If the soil contains rocks, the pile may stop going deep.

In addition to metal ones, there are also concrete screw piles on sale. What are concrete screw piles? They have the same principle of operation, but they are more durable and less susceptible to corrosion. The only drawback in installation is the heavy weight, which, however, simplifies the screwing procedure.

When all the piles are mounted, a wooden or metal grillage (frame) is installed on top of them, on which the house is then assembled

Screw piles advantages and disadvantages:

* Easy DIY installation, no special equipment or concreting required

* Not susceptible to frost heaving, can be installed at high ground water levels

* Large selection of diameters for different loads

* Low price compared to full-fledged tape

* Not all primers can be screwed into

* Not suitable for heavy stone houses, the metal will eventually be destroyed by corrosion in the ground

* There is no basement, the basement must be additionally covered and insulated

Screw piles are ideal for wooden and frame houses and soils without rock inclusions. Although the advantages of a foundation on screw piles make it possible to use it for heavier buildings.

Driven piles

What is a pile-driven foundation?

This is another type of grillage foundation, the base for which is concrete wedge-shaped piles driven into the ground.

Driven piles are manufactured in factories from branded reinforced concrete. Installation of such piles occurs using a special pile-driving installation and is not possible with your own hands. The task is the same as for screw piles - to reach dense soil. For this purpose, concrete piles range in length from 3 to 36 meters (composite piles).

The most common type of driven piles is square section. The piles are installed using special equipment. Recesses are pre-drilled into which piles are inserted and driven in with a special installation

Unlike screw piles, driven piles can be mounted on almost any soil. If it is known that there is a layer of dense rock along the path of the pile, then before driving it, a well is drilled through this layer.

In private housing construction, this technology is not often found, since for small houses such strength is in most cases excessive. Installation is also quite expensive and requires special equipment and professionals.

Depending on the material of the walls of the future house, the driven piles are connected to each other with a concrete grillage or wooden frame

Advantages of driven piles and their disadvantages:

* High strength, not afraid of corrosion

* Can reach great depths (36 m)

* Not afraid of heaving and groundwater

* Expensive installation

* Special equipment required

*No basement

Driven piles are suitable even for very heavy and critical buildings; they allow construction on almost any soil, except rocky ones.

Bored (cast) piles

What is a bored foundation or a bored foundation with a grillage?

This is an ordinary pile foundation, only the piles are not screwed or driven in, but are poured from concrete into pre-drilled holes in the ground.

These piles are poured directly into the soil at the site. To do this, holes of a given depth are made at points in the ground established by the project using a mechanical or hand drill. Asbestos or plastic pipes are then inserted into these holes. The reinforcement is immersed into the pipes and concrete is poured.

The process of manufacturing bored piles using TISE technology using a hand drill. This method is suitable for small houses and loose soils. If there are a lot of piles to be poured under the house or the soil contains large stones, then it is better to resort to the services of an auto drill

To enhance the load-bearing capacity of piles during manual drilling, a drill is sometimes used, which can widen the bottom of the hole. This widening significantly increases the size of the pile base.

What is the TISE foundation?

TISE is a pile foundation made using a special drill that makes expansions in the lower part of the boreholes.

Drilled piles have become widespread because they are very easy to install. You can often find a combination of them with a shallow strip foundation.

Bored piles, like their screw and driven counterparts, end in a beam or grillage. Also, such piles are often used as a support for the grillage of a shallow strip foundation. However, in this case, you need to make sure that in winter the forces of frost heaving will not lift the grillage along with the piles

You can calculate online the volume of concrete and reinforcement for the manufacture of a pile-grillage foundation using our calculator

Pros and cons of drilled piles:

* Easy DIY installation

* Low cost

* Not subject to heaving and the influence of groundwater

Cannot be used on all types of soil

Bored piles are suitable for the construction of light and medium-sized houses and are easy to make yourself. In combination with a shallow tape, they are also suitable for heavier houses.

Conclusions. A pile foundation will be an excellent solution if the bearing capacity of the soil does not allow it to support the weight of the house with a strip or slab foundation. The piles are simply screwed or driven to the depth of strong soils. Screw piles can be installed with your own hands, and they are perfect for wooden and frame houses. Driven and drilled piles can support the heavy weight of a brick house.

Which foundation is better for a frame house?

To choose a foundation for a frame structure, you should take into account the dimensions of the house, the number of floors, the groundwater level, the depth of soil freezing, the need for equipment in the basement and ground floor.

• Columnar foundation
  Which foundation is better for building a house on a frame basis? If the soil is stable, the optimal solution is a columnar base. It is erected in the same way as a foundation on piles, but the depth will be less. The main advantages are ease of installation and repair, low cost. The pillars can be made of stone, brick, rubble; it is also permissible to use asbestos pipes or pour concrete.
• Strip foundation with a shallow depth.
  Such a foundation is often used in the construction of frame cottages. It can be installed in a short time, and the financial costs will be small. You can equip a basement. Compared to a standard foundation, a strip foundation will be buried less.
• Slab foundation
  Which foundation is better for a private house if the soil is complex and floating? You should choose a monolithic base with reinforced reinforcement that can withstand the load from the house system. In this case, soil movements will not be transmitted to the frame, because the slab dampens them. If you choose a slab foundation, you will not need to create a foundation pit, drive piles and reinforce the floor; thermal insulation will also be easier. However, it will no longer be possible to equip a basement; in addition, the cost of such a foundation is quite high.
• Pile supports
  Which foundation for a house is better and cheaper if the soil is clay or sandy? The optimal solution is metal screw piles. Traditional concrete pillars are best used on heaving soils. Thanks to a special installation technology, it is possible to make a foundation without the use of construction equipment.

What other advantages do pile supports have:

• they can be installed at any time of the year, no matter whether it is winter or summer;
• such a foundation is suitable for an area with a large difference in height, on a slope, in a hard-to-reach place;
• the cost of the support is low;
• it is easy to repair piles, as well as replace them if necessary;
• long service life from 80 to 100 years.

Despite the above advantages, this type of foundation also has disadvantages. So, if the soil is rocky, the blades of the metal trunk may bend, which means it will not be possible to build a frame house. It is also impossible to equip a basement.

Columnar foundation

A columnar foundation is a foundation for construction made of small columns connected by a grillage

It is mainly used for the installation of outbuildings and in the construction of small light houses.

The foundation consists of columns made of monolithic concrete or blocks, which, like piles, are located under the load-bearing walls of the house at a certain interval. After installation, a grillage or beams must be installed on top of the posts to connect them into a single structure.

The most widespread is the columnar foundation made of 20x20x40 blocks. Such blocks have a low cost, they are durable and easy to install.

Cinder blocks are excellent for constructing a columnar foundation. They are lightweight and easy to transport and install, and are strong enough to withstand the weight of any wooden building.

The construction technology is very simple:

• Markings are made on the ground;
• In the places where the pillars are installed, the fertile layer of soil is removed;
• A sand cushion 200 mm high is filled in and compacted;
• Blocks are installed. Each subsequent row is made across the previous one, the masonry is carried out on a durable mortar;
• The upper blocks are leveled with mortar;
• A grillage is installed on the anchor.

The foundation can be used on solid, non-heaving soils such as rock, gravel or sand. But even in this case, uneven settlement of the foundation and skew of the walls cannot be ruled out. On heaving foundations, a columnar foundation behaves even worse.

To be fair, we note that there are columnar foundations that can withstand enormous weight. To do this, they are buried deep into dense rocks, and each pillar is filled with a reinforced concrete monolith with a large support area. Hence the very high price, and the main scope of application is industrial and multi-storey construction.

Advantages and disadvantages of a columnar foundation:

*Lowest construction cost

* High speed and ease of DIY construction

* Not suitable for heavy and critical buildings

* Not suitable for heaving substrates

* High probability of uneven subsidence, since each pillar lives its own life

*No basement

Results. It is better to use a columnar foundation only for the construction of small outbuildings, such as a bathhouse.

Types of foundations for a house by design

When creating country houses, the following types of foundations are used:

1. Strip foundation . It is a solid base made of reinforced concrete or brick. The foundation is laid under the load-bearing walls of the building; it is made in the form of a closed contour or strip, which is why it is called strip. This type of base is used most often.
2. Slab foundation . Another name for such a base is “floating”; it is made in the form of a continuous monolithic slab of concrete. Thanks to this solution, the load is distributed evenly.
3. Columnar foundation . Made in the form of a system of concrete, brick, stone or wooden pillars, which are located at the same distance from each other in the area of ​​load-bearing walls and corners of the building. To make the structure stronger, the pillars are combined with a grillage, which is a connecting frame. However, a columnar base can be erected without a grillage. This foundation is best suited for small and light buildings.
4. The pile foundation is made of supports screwed or driven deep into the ground, and not installed in holes, as is the case with a columnar foundation. Piles can be made of metal or reinforced concrete and are suitable for installation on loose, heaving soils.

What is the best foundation for a house? To answer this question, it is necessary to take into account the size of the building, the materials of the walls and ceilings, the type of soil, the level of its freezing, the depth of groundwater, the presence of underground communications, as well as the need to arrange a basement.

Foundation slab + USHP

USHP foundation what is it?

This type of foundation is a thick reinforced concrete slab that is located under the entire house. Due to its large area and thickness, such a foundation perfectly distributes the load on the ground, and therefore can be used even on foundations with poor bearing capacity.

The walls are erected directly on top of the slab along its perimeter. A properly made foundation can easily support walls made of foam block and wood.

At the same time, the large area and thickness determine the main disadvantage of such a foundation - its high cost. It takes a lot of concrete to pour.

Calculate the volume of concrete, the length of the reinforcement and the number of formwork boards for pouring the foundation slab in just a couple of steps using our online calculator

The most widely used foundations in the construction of private houses are USP (insulated Swedish slab). To install such a foundation, the fertile layer is removed, after which the pit is filled with crushed stone and sand and compacted. Insulation (XPS) is laid on top of the sand preparation, onto which reinforcement and formwork are installed. Before pouring concrete, all communications are carried out in the floor: heated floors, sewerage, plumbing, electrical.

Before pouring the insulated Swedish slab into the formwork, reinforcement, heated floors and all necessary communications are laid. Given the large volume of the slab, it is better to fill it using a concrete pump

The walls of the house are erected directly on the concrete slab. A building with such a foundation turns out to be without a basement, and the communications laid in the monolith are almost beyond repair if damaged.

If a building needs a basement, the slab can be buried. After installing the slab on top of it, the basement walls are built according to the principle of constructing a strip foundation. However it is very expensive.

Advantages of USP foundation and its disadvantages:

* Suitable for soft soils

* Acts as the subfloor of the first floor or basement

* With a basement-less design, there is little excavation work

* High cost of work

* Difficulty in repairing buried underground communications, as well as installing new ones

Results. The slab foundation is suitable for the construction of low-rise buildings without basements on soft soils. There is only one main drawback - high cost.

Monolithic foundations

A monolith is a solid reinforced concrete structure on which the load-bearing elements of the structure rest. Such foundations are strong, flexible, compensate for soil vibrations, do not transmit them to the walls of the structure, and eliminate the risk of deformation and destruction. They can serve as the basis for any structures, from country houses to high-rise multi-storey buildings. Suitable for soft soils, used in seismically active areas.

Disadvantages: high cost and energy consumption.

• A large amount of concrete and reinforcement is required.
• Requires the use of heavy equipment.
• Formwork is required around the entire perimeter of the structure.

The price (material + installation) of a 20 cm thick slab with a minimum distance of work is from 4 thousand rubles per square meter. The construction time for monolithic foundations, including floating and strip foundations, is at least 28 days (determined by the time required for the concrete to harden).

Frequently asked questions about foundations

In conclusion, we will answer a few frequently asked questions:

• Which foundation is best to make depends on the weight of the house and the bearing capacity of the soil. In most cases, for stone houses (bricks, blocks) a strip foundation is suitable; for basement-less frames and wooden ones, a pile foundation is good and cheap; USF is advisable on soft soils or with high groundwater level;
• What should be the depth of the strip foundation - for a traditional foundation this is the level of soil freezing (see the map at the beginning of the article), for a shallow strip foundation it is enough to dig just below the depth of the fertile layer;
• What should be the depth of twisting of screw piles - to dense soils (will have to be determined by test drilling), but not below the freezing depth;
• What kind of foundation to make if groundwater is close - shallow with mandatory insulation of the base and blind area, piles or USP;
• What kind of foundation to make on heaving soil - traditional strip, piles or USP.

Which foundation is better for a log house?

The popularity of cottages made of rounded logs is explained by their attractive appearance, high thermal insulation characteristics, ease of installation, cost-effectiveness and environmental friendliness. A structure made of wood has a long service life, the main thing is not to violate the construction technology, and also to apply a protective impregnation to the wood.

It is also worthwhile to properly equip the foundation of the house, otherwise the foundation will deform unevenly and the log house will skew. As a result, the doors and windows will jam, gaps will form between the crowns, cracks will appear in the logs, and the structure will eventually become unusable.

1. Monolithic foundation Since such a foundation follows the seasonal movement of the soil, it is called “floating”. Therefore, it can be used when constructing houses on any soil. Such a base can withstand even the heaviest load. Before you start creating a foundation, you need to calculate how heavy the structure will be, find out the type of soil, and the groundwater level. You should weigh the pros and cons of creating a monolithic foundation for a house made of wood. After all, you can choose a more budget-friendly base option.
2. Columnar foundation for a house
   If your budget is limited, then this is the foundation you should choose. However, it cannot be erected on heaving, unstable soils. Such a foundation is suitable if the structure is being erected on a site with differences of up to two meters. Most often, columnar foundations are used in the construction of lightweight frame houses and verandas. The pillars can be brick, wood, concrete, stone, reinforced concrete or asbestos pipes. The market also offers ready-made concrete blocks. They are installed in the corners of the house at a distance of one and a half to two meters and under frame racks in places where walls intersect.

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

Many people prefer this material due to its qualities: lightness, strength, ease of use and budget. The main advantage is that it is easy to process. But if you compare aerated concrete with wood, brick or concrete, it will be more fragile. Before you start building a house, you should decide which foundation is better.

For example, if over time a crack appears in the base of a wooden house, nothing bad will happen. However, if the structure is made of aerated concrete, the wall will be severely damaged. Many people believe that due to the lightness of aerated concrete, the base can be made more affordable. Actually this is not true.

Which foundation is better for a two-story aerated concrete house? The optimal solution is a monolithic slab, strip, columnar or pile foundation.

1. Monolithic slab

If you can’t use a strip foundation, what is the best way to pour the foundation of a house? The best option is a monolithic reinforced concrete slab. It can be used on weak-bearing, swampy, heaving soils, or if the groundwater level is high.

If the monolithic slab is made in compliance with the technology, the structure will not deform due to changes in ground level. For example, during seasonal temperature fluctuations, when the earth's surface freezes and thaws.

2. Columnar base

This option is worth choosing if your budget is limited. But using a columnar foundation for an aerated concrete house is allowed only if:

• the soil is quite strong, there is no groundwater in nearby layers;
• the foundation pillars are laid 10–30 cm lower than the soil freezing level;
• construction site without slope;
• foundation pillars are located in corners, at the intersections of walls, as well as under other structural elements of the building that experience the maximum load;
• The grillage acts as a strong tape that connects the structure. This means that it must be created in compliance with the rules of reinforcement, as when forming a traditional foundation strip.

3. Pile foundation

When groundwater is located close to the ground surface, a pile foundation is best suited. Piles, compared to pillars, have a smaller diameter but a longer length.

Such a foundation is created from standard pipes if the structure is not heavy. In this case, they are driven in with a sledgehammer or screwed into the ground using construction equipment, leveled, and trimmed so that they are at the same level. You can carry out the work yourself using special devices or construction equipment. In the latter case, all work on the construction of piles for a house, fence, terrace, gazebo or outbuilding can be completed in one day.

In addition, pipes with blades can be used to create the foundation.

The main difference between such a foundation is that it will need to be loaded with the weight of the structure in the winter. Otherwise, due to heaving in cold weather, the pipes will be pushed out. The house should be planned so that the cottage box is ready by autumn.

The dimensions of the pile foundation and the depth of the piles are determined by the gas-block structure and the type of soil. Calculations should be carried out in each situation separately. It is recommended to contact a professional to plan the construction work.

4. Tape base

If you are looking for an answer to the question of which foundation is best for a house, the right solution is strip foundation. However, despite all its advantages over other options, this foundation also has disadvantages. The depth of the foundation will differ in each specific case. It is necessary to make formwork around the perimeter of the house for pouring.

Typically, the width of the base should be 7–10 cm greater than the width of the gas-block wall. It is necessary to reinforce a monolithic strip-type foundation in compliance with the technology, no matter how deep it lies.

If you want to build a two- or three-story house, or if you plan to equip a basement and basement, the foundation must be deeply recessed. This type of foundation is suitable when the structure is located on heaving soil. In this situation, the base should be located below the freezing point of the soil.

Which foundation is better for a house made of foam blocks?

Today, many people prefer to build cottages from gas silicate blocks. Why do land owners choose this material? The reason is the special properties of porous concrete, which make the construction of houses much easier. Time and labor costs are reduced, while the structure is obtained with high thermal insulation properties.

When you plan to build a house using porous concrete blocks for load-bearing walls, it is necessary to take into account the properties of the material when creating a building plan. All stages of construction using gas silicate will have their own peculiarities, including the construction of the foundation.

Foam blocks are produced using a special technology, which produces a concrete material with a porous, cellular structure, which determines its properties. There are many materials with similar characteristics: foam concrete, as well as aerated concrete, we talked about them in this article. Even though they are similar, there are still differences. However, they do not affect the foundation design in any way. This means that the foundation for a house made of foam blocks will have the same qualities as the foundation for a building made of aerated concrete.