Examples of prices for pile-screw foundations:

Example 1	Example 2
Pile foundation for a bathhouse 6 x 6 Price: 36,000 rubles	Pile foundation for frame-panel house 6 x 8 Price: 48,000 rubles
Example 3	Example 4
Pile foundation for a log house 6 x 9 Price: 60,000 rubles	Pile foundation for a house made of foam blocks 6.5 x 6.5 Price: 68,000 rubles

Many people wonder on what foundation it is most rational to build a house. First of all, it is necessary to determine the type of soil at the construction site. In some areas, additional strengthening of foundations is required. These include mobile, floating and highly heaving soils.

The most widely used foundation is made of screw piles, which is the best option for construction on all types of soil (except rocky). This is one of the most reliable and simple technologies. Screw piles are used in the construction of buildings of various types and purposes. Pile foundations are especially important for objects that are being built in difficult areas. Screw piles are the best option for:

• lowlands and banks of reservoirs;
• slopes with varying elevations.

The technology involves the procedure of screwing screw piles into the ground to a depth below the freezing level. As they deepen under the blades, a so-called cushion is formed. It becomes compacted as the piles deepen. Upon reaching solid layers of soil with good load-bearing capabilities, the “cushion” becomes as dense as possible. Further penetration is no longer possible, which means that the support structure is installed correctly.

Stages of installing a screw foundation

The foundation made of screw piles is one of the simplest. Installation of structures does not require the use of expensive construction equipment. The pile can be screwed in either manually or using a special machine. With the support of professional builders, a foundation on piles can be built very quickly.

How are screw piles installed? This process includes several stages:

• Screwing in piles can be done either manually or mechanically. The method does not in any way affect the quality of the foundations, since after the formation of a rigid cushion, further deepening of the pile is impossible even when using powerful equipment.
• Trimming to the same level. Foundations on screw piles are not affected by elevation changes or other terrain features. Trimming can be done at any level, and the height of the base of the future house depends only on your desire.
• Filling the internal cavity of the piles with cement-sand mortar. This is done to displace oxygen, which eliminates the occurrence of corrosion inside the piles and increases the service life of the structure.
• Welding of “heads” or tying with channels. We can offer you the installation of caps with holes for subsequent fastening of timber or tying with a channel, which provides additional strength to the load-bearing walls of the house and evenly distributes the load on the screw piles. It is often used for heavy buildings or for additional strengthening of load-bearing structures of light houses. A foundation on piles is suitable even for the largest and most complex objects.

Advantages of a foundation on screw piles

Screw piles are widely used in construction for a number of reasons. First of all, this is the affordable price of the structures. Also, a screw pile helps save time and money, based on its other advantages:

• Using a screw pile, you can build a house on the day the foundation is installed, which significantly reduces time costs. The fact is that the foundation on piles is ready to take the design load immediately, unlike other concrete-based solutions.
• The cost of a pile-screw foundation is another important advantage. The low cost of the products themselves and the absence of concrete work when installing the foundation greatly saves the budget.
• Turnkey installation of a pile foundation allows you to completely eliminate the need to rent heavy construction equipment, which greatly reduces the cost of work. Piles with a diameter of up to 133 millimeters can be easily screwed in by hand. In this case, the quality will be even higher compared to the use of mechanization.
• Low requirements for soil and surrounding landscape. Screw piles allow the construction of foundations on slopes, peat, and also on heavily waterlogged soils. In addition, the presence of nearby trees with a developed root system and the passage of infrastructure communications are not a hindrance. Thus, buildings can be erected on stilts both in dense urban areas and in the open air, without damaging the environment.
• Possibility of further modernization. The building can be easily expanded in the future if necessary. For example, if you want to add a bathhouse to your dacha.
• Piles are an ideal choice when constructing wooden houses. This solution provides excellent ventilation of the underground, which prevents dampness and rotting of the wood.
• Unlike strip or tile foundations, screw foundations can be easily repaired.
• A high-quality pile treated with anti-corrosion substances can last more than half a century.

Construction of a foundation on piles: how to choose the right products for installation?

It all starts with a study of the soil on the building site - the structure, the depth of soil freezing and the groundwater level. Timely detection of soil heterogeneities will save a lot of time and money in the future.

Based on the information obtained, the number of pile structures, the depth of immersion, and the distance between them (which should not exceed three meters) are calculated. It should also be understood that each pile has several important characteristics that should be considered. We list the most important of them:

• Pipe diameter. This parameter is determined by the design load that the pile foundation will experience. The most commonly used products are those with a pipe diameter of 108 mm.
• Length. In most cases, piles are buried approximately 2-2.5 meters, but the specific depth must be determined during test drilling.

Turnkey pile-screw foundation from "ZSK"

Do you need a foundation on stilts? contact us!

we know interesting facts about pile-screw foundations and dispel several myths about this technology.

There are several opinions about pile-screw foundations. Some consider this option ideal for relatively light frame houses and log houses, while others criticize it, citing their own arguments. Let's together understand the myths that exist about foundations on screw piles.

Pile-screw foundation

Myth one: a pile-screw foundation is unreliable

In fact, there are reviews from homeowners that a house built on screw piles wobbles, sways, and the piles themselves begin to protrude. So, unreliability is not a myth at all, but the pure truth? Not really. If problems arise with a house built on a pile-screw foundation, it means the construction technology was violated! We wrote about what the optimal size of screw piles should be. In addition, the reasons for instability of the house may be:

• Insufficient depth of piles;
• The diameter of the piles is not large enough;
• Excessively deep pit;
• Small number of piles;
• Weak-bearing, too soft soil;
• Errors in calculating the load on piles.

If all technologies were followed, calculations were made accurately, and installation was carried out by professionals, there will be no problems with the pile-screw foundation! In this case, it will be possible to say for sure that the unreliability of such a foundation is a myth.

Myth two: a pile foundation can be erected in just a day

Of course, installing screw piles is much faster than pouring a concrete foundation. However, this is not to say that you can cope in just a day! This is not always the case. Firstly, professionals always carry out test drilling and test screwing. This is necessary to find out the characteristics of the soil.

It may be weak-bearing, too hard or rocky. The presence of stones in the soil will seriously complicate the screwing of screw piles, and in some areas the soil can be so strong that even metal will not withstand. In addition, sometimes it is impossible to use a drill and other special equipment on the site. In this case, the construction time for the foundation is also delayed.

Myth three: screw piles will rust within 10 years, the house will not last long

Experts say that a correctly selected screw pile will last at least 50 years. Service life depends on the following parameters:

• steel grades;
• metal thickness;
• quality of metal protection - painting, galvanizing, anodizing;
• soil aggressiveness.

In saline and acidic soils, metal rusts faster. In addition, special paint should be used to protect it and an anti-corrosion coating should be provided. You should not use cheap compounds.

Myth four: during installation, the blades of the pile may break off, causing it to sag

This can only happen in two cases - low-quality screw piles were initially selected and the installation technology was violated. If the soil is strong, rocky, and the installation was carried out harshly, then, of course, the blades can be broken. However, if you choose high-quality piles and do everything according to the rules, there will be no problems.

Myth five: you can install a pile-screw foundation only in the warm season

Not true! In winter, the soil, of course, freezes, but a small top layer can be removed using a chipper and you can easily install piles. Experts say that in winter it is often even easier to work, and no potato beds interfere with the plot.

Myth six: screw piles are a new technology, not yet proven by time

In fact, pile foundation construction has been known since ancient times. True, then the piles were driven into the ground. In 1833, Irish civil engineer Alexander Mitchell patented a device called the "screw pile". Unlike conventional piles, screw piles are screwed into the soil. Initially, such piles were used for the construction of piers and lighthouses, then the scope of application expanded significantly.

In Russia, screw piles have been known since the beginning of the last century, in particular, they were widely used in the field of military construction, in permafrost conditions. That is, we are not talking about any new product!

Research in the field of application of screw piles has been carried out more than once, including in the USSR, the advantages of this technology have been proven by specialists. True, screw piles began to be used in Russian low-rise residential construction later; previously they were considered the prerogative of the construction of industrial and military facilities.

Myth seven: all screw piles are the same, they differ only in price

Absolutely false. Piles differ not only in quality, size, metal thickness, and the presence of corrosion protection, but also in their scope of use. For example, there are piles created specifically for heaving, waterlogged or permafrost soils. In addition, they can be cast or welded. So you should choose based on your needs, preferably in consultation with specialists.

Myth eight: you can screw in screw piles without a pit

Professionals consider this a violation of installation technology, recommending that a small pit be made. This is due to the fact that the top layer of soil is usually the loosest, and the blades of the pile at the first stage loosen the soil until they reach denser layers. Often, without a pit it is completely impossible to screw in a bladed pile. In addition, concrete can be poured into the pit to strengthen the structure.

Myth nine: screw piles are ideal for building a house on a slope

Yes, this option occurs quite often. However, a house on a slope can also stand on other types of foundations; before choosing a foundation, it is important to conduct geological surveys. A pile foundation may be the simplest choice in this case, but it is by no means ideal.

Myth tenth: the floor of a house on a pile-screw foundation will be cold

This myth is connected with the fact that cold air will circulate under a house standing on stilts. However, if the floor is reliably insulated, the problem can be easily solved. And ventilation, by the way, will prevent the floors from starting to rot.published

If you have any questions on this topic, ask them to the experts and readers of our project.

An inexpensive pile-screw foundation is an excellent alternative to a strip concrete foundation. Its use is especially important on difficult wet or loose soils and uneven terrain. Piles are widely used in private construction and to reduce the cost of outbuildings: bathhouses, garages, greenhouses, verandas, etc.

On what soils is a screw foundation used?

Water-saturated soils, sands, sandy loams and loams are most susceptible to winter soil heaving. At the same time, even a fairly deep foundation can begin to be pushed out of the ground. In the spring, when it thaws, it shrinks unevenly.
Reliable support is also required when building on loose soils: after all, you have to go too deep. The use of strip foundations in such cases becomes unprofitable. In such cases, piles come to the rescue.
The first cast iron screw piles were developed by the Englishman A. Mitchell in 1933 as an alternative to driven ones. They were in the form of a pipe, one of the ends of which was made in the shape of a specially shaped blade and was pointed. Thanks to this design, the pile was easily screwed into the soil, further compacting it, much below the freezing depth and was securely fixed in it.

Structure and appearance of piles

Initially, such structures were used only in the construction of bridges and temporary structures, and only then began to be widely used for the construction of foundations for residential and industrial buildings and military facilities, berths, and marinas.
In our country, they are most often used for the construction of buildings in permafrost conditions (in the regions of the Far North and Far East). In private construction, in recent years, pile-screw foundations have begun to be used in the construction of housing in wetlands, near the passage of groundwater, and for the construction of outbuildings.

Scope of application of pile foundations

There are two types of screw piles:
piles-peaks: with a pointed tip; designed for light and loose soils;
pipe piles: with a toothed crown at the lower end; used on sticky soils.

Types of piles

TO main advantages piles include:
possibility of installation on any, including difficult soils and even on water;
ease of installation, minimal time spent on their installation, no excavation work;
possibility of installation in winter;
such structures are not susceptible to buoyant loads;
if necessary, the ability to dismantle and reinstall;
high strength: depending on the type of piles, they can withstand a load of 4-18 tons;
increased seismic resistance;
durability;
economic benefit: their cost is 30-60% lower than the price of a concrete foundation.

TO shortcomings pile-screw foundation can be classified as:
the inability to install them in soils with a lime layer, peat bogs, fluid soils and rocky areas;
equipping a basement in a house built on stilts is very problematic - its insulation will be equal to the cost of the foundation itself.

Calculation of the required number of piles

The first step is to determine foundation load. To do this you need to sum up:
the weight of the building, including not only external but also internal walls, floors between floors, roof, facade decoration;
interior items located in the house, furniture, equipment, etc.;
weight of people in the house: according to SNiP for private residential buildings, data is taken at the rate of 150 kg per 1 sq. m;
snow load is determined according to SNiP depending on the area of ​​residence.

Snow load map

The resulting weight is multiplied by coefficient 1.2. To find out the maximum load (bearing capacity) of each pile, you should know soil resistance. To do this, you should use a special table (see photo).

The depth of their immersion I depends on the degree of soil freezing (this data varies for each area). For example, for the Moscow region, the depth of soil freezing is 1.4 m.

Installation of piles

The work is carried out in the following sequence:
1. Using stakes, the locations of the piles are marked in the selected area. To avoid mistakes, you should check the distance between them with the drawing, and also carefully measure the dimensions of the corners and diagonals.

2. To simplify screwing in the piles, prepare a small hole slightly wider (2-3 cm) than the diameter of the blade. The depth of such a hole is 10-15 cm. Too deep holes that loosen the soil are unacceptable.

Hole for pile

3. Piles with blades up to 300 mm can be screwed in manually without the use of machinery. For this purpose we are preparing lever arm from scrap, which is inserted into the hole in the upper part of the pile, and pieces of pipe measuring 3 m. As the screw deepens into the ground, the pipes will be put on the scrap to increase the length of the lever arm.

4. At least three people will be needed for the work. Since the pile must be installed strictly vertical, it is necessary that during its screwing in one of them controls the process of its installation.

The pile must be installed strictly vertically

Advice. If, when installing one or two piles, an obstacle appears in the way and they no longer go into the ground, it is permissible to cut off the top and leave them in that position. But in the corners of the house piles should only be installed to full depth.

Screwing in a pile manually

5. After installing all the piles, their excess length is trimmed to the level.

6. To strengthen it, concrete is poured into the hollow shaft of the pile.

Concreting

7. At the cutting site at the top of the pile the head is welded.

Welding the head

Making a grillage

Grillage is the upper part of the foundation, combining the pile heads and providing a more uniform load on the base. Thanks to such a rigid ligament, if one support fails, the weight will be transferred to the others. The grillage can be made from:
concrete;
timber or boards;
T-beam;
metal channel or corner.

Advice. If the house is made of timber, the first row of the wall can be used as a frame.

When installing a concrete grillage on top of the piles, formwork is prepared, a reinforcing belt is installed and mortar is poured. The channel, I-beam and angle are welded. The wooden grillage is assembled with bolts.

Types of grillage

This technology is used to speed up the construction of not too heavy buildings and other architectural structures. It is suitable for constructing reliable foundations even on soft soils. Its use helps prudent owners. Within the framework of this guide, we will tell you what it is like to build it on screw piles, with your own hands or with the help of specialists, what pros and cons you should pay attention to, as well as how repairs and finishing of pile structures are carried out.

Read in the article

Foundation on screw piles

When preparing to build a house, you need to correctly answer various practical questions:

• It should be determined whether a pile-screw foundation is really suitable for a building of a certain size made of.
• Information on how to select basic materials and components to implement a project at a reasonable cost will be useful.
• You definitely need to learn how to make the calculation correctly so that the created structure remains stable over a long service life.
• It is necessary to clarify how to properly mount the base, so as not to complicate subsequent construction operations, whether it is necessary.
• After determining whether piping is needed, you will have to decide what to cover the base with in order to get a good appearance and improve consumer performance.

The answers to these questions are given in this article. When studying it, one must not forget about the individual characteristics of the use of the building. For example, the load will increase significantly if the house is often used to receive a large number of guests.

For your information! We must remember that sewerage and other utility networks are installed in a residential building.

Pile foundation with monolithic grillage

This design is installed according to the following scheme:

• Calculate the loads that will be created during operation.
• Depending on it and taking into account the characteristics of the soil, products that are suitable in terms of technical parameters are selected.

• Products are screwed in manually or with the help of power units, to the level of dense layers.
• The levels of the pillars are cut horizontally.
• Support plates are attached to them and installed.
• If necessary, make cladding.

This part of the structure prevents water from accumulating near the building. With an efficiently operating storm drainage system, liquid will be discharged in a timely manner. It will not provoke corrosive processes that can destroy metal immersed in the ground.

Taking into account the expected loads, not only the parameters are selected, but also the material of the grillage. Below we will discuss various areas of application of this type of piles using specific examples.

For such a project, pipes with a diameter of 55 to 80 mm and a wall thickness of 3 to 4 mm are suitable. If you purchase products of sufficient length, the upper part can be used as a power frame.

In this combined version, piles from 75 mm in diameter are used. A shallow concrete grillage is mounted on them. During pouring, protruding mortgages are installed in it. A support structure with transverse stiffeners is welded on top.

Such structures are subject to strong dynamic mechanical loads, so the requirements for reliability increase.

If massive equipment is installed, then this is where additional reinforcing elements must be installed.

A wooden grillage is suitable for this type of construction. When the load increases, a metal channel is used. If the dimensions of the building exceed 10x10 meters, the walls are made of foam blocks and large piles are used. Choose a diameter of 108 mm or more with walls made of 9 mm steel.

Important! After completion of installation, the supporting screw part should be at a level below the maximum freezing of the soil in a certain region. The required values ​​can be found on the Internet, or by contacting the municipal architectural bureau.

This figure shows how standard components are modified to solve individual engineering problems:

• Different loads are distributed on piles with a diameter of 108 mm (1) and 76 mm (2).
• To strengthen the central part, steel channels (3) were added. The side parts rest on corner supports (4).
• To prevent the metal heads (5) from contacting the wood, a layer is installed on top.
• (8) with floor covering (10) rest on a wooden grillage. The log wall is mounted on strong pillars.
• To prevent deformation for a wooden house (1-2 floors), a distance between piles of 200-270 cm is recommended.

For your information! Even for a gazebo or other light structure, it is necessary to make an accurate calculation. The data provided in this section is approximate. They are adjusted taking into account the building materials, soil characteristics and other important factors.

Related article:

How to do it (detailed step-by-step instructions with photos) and how difficult such work is - these are the issues we will look into in our review. We’ll also get acquainted with useful tips and recommendations from experts.

Disadvantages of a pile-screw foundation

When studying the question of what to choose to create a support for a building structure, the negative nuances and advantages are studied together. During the comparison, they check the complexity of technological operations, durability, which is cheaper from the presented options. For domestic climatic conditions, it matters whether installation can be carried out in winter.

If the soil is classified as heaving, or frequent flooding of the area occurs, enlarged blades are used. To penetrate the frozen layer in winter, they use not a sharp tip, but a drill (the serrated edge of a pipe).

Piles are suitable for working in areas with difficult terrain. They can be used to install not only the house itself, but also a pier. They will provide a solid service life when placing the object near an open body of water. They can be installed in frosty weather, so you can eliminate the corresponding restrictions when working with pouring concrete products.

An experienced team, even without the use of power drives, is capable of driving more than 20 piles in a day.

For your information! The figure shows that for high-quality reproduction of the technique, at least four people are required. Two create the necessary forces using levers. One – supports the pillar during rotation. The manager controls the verticality of the installation and coordinates the actions of workers.

In this embodiment, a gearbox with a large gear ratio is used. A powerful drill is suitable for the drive. If there is no 220 V network on the site yet, a mobile electric generator is used.

Such equipment will allow you to quickly create a large support field. When comparing different options, all real costs must be taken into account together. Sometimes ordering specialists with equipment is cheaper than independent experiments. It should be remembered that manual technology will require assistants.

Will a typical concrete foundation be reliable without preliminary calculations? Will the base settle over time or not if it is not installed on the site? The answers to these questions are given above. But the following nuances also deserve attention:

• Piles of this type do not draw moisture from the soil, so the structure is not subject to corresponding negative impacts.
• In a building raised on supports it is necessary. It is much simpler and more effective compared to a standard concrete foundation.
• The use of this technique is not accompanied by large earthworks. Eliminating the need for level ground reduces overall costs. Compared to a typical strip foundation for a similar load, they will be 25-45% less.

For a full analysis, it is necessary to find out which is better, TISE or screw supports.

These products are created as follows:

• Using a drill, a hole is formed in the ground.
• A special lower nozzle allows you to form a dome-shaped extension in the lower part.
• A tube made of roofing felt and construction pins are installed in the well channel.
• Next, concrete is poured.

The main advantage of TISE piles is the absence of corrosion processes. But they cannot be used immediately. You need to wait until the mortar hardens, which under normal temperature conditions ranges from 7 to 10 days. On the other hand, it should be noted that reinforced concrete structures have a relatively greater load-bearing capacity.

Do-it-yourself pile foundation: step-by-step instructions, video

The video below shows the corresponding technology. But simply copying it is not acceptable. A project should be prepared. Let it not be made according to the canons of engineering standards. But even a basic support arrangement scheme is better than the complete absence of working documentation.

You need to find out for yourself what new products manufacturers offer. Some new types of piles are inexpensive, but have excellent consumer characteristics.

Laying out a site for a foundation in this case is simpler than carefully leveling a part of the land for a monolithic slab. However, we must not forget about the possibility of using high plinths to solve economic issues. You should remember the need for laying, networks and communications.

Important! Below are detailed step-by-step instructions. She will help you build a reliable foundation with your own hands without mistakes. But we must add to this description corrections that are determined by the parameters of a particular structure and its application.

Screw piles for foundation

Above were only some types of metal products in this category.

Increasing the number of blades simplifies screwing, provides greater support strength and increases load capacity. To simplify the connection of levers and other devices, holes are cut out. To simplify the connection of grillages, flat or “U”-shaped platforms are welded. A second screw is added to make it easier to maintain the vertical position.

To strengthen the structure of the head, stiffening ribs (2) are added to it. The surface is protected from corrosion by multi-layer paint coatings (3).

Such products are made from cast iron. Casting helps eliminate the disadvantages of welded joints. These tips, even without special treatment, are highly resistant to corrosion. They are not damaged when passing through dense rocks and retain excellent functional condition after decades of use.

Responsible manufacturers use GOST standards to prevent destructive oxidation processes. Cold technology is cheaper than hot galvanizing. But the second version of the protective coating is held more firmly on the surface of the base metal. Powder coating ensures a high quality layer. But if there are stray currents in the ground, it can be damaged in 30-40 years.

To extend service life, experts recommend paying special attention to the ground-to-air transition area. In some cases, it is suggested to wrap the corresponding area with a polymer film. Regular inspections with updating the paint layer are also used.

To eliminate unnecessary hassle, you can make additional investments.

The calculated value of the bearing capacity is determined by multiplying the area of ​​the screw (projection on the horizontal plane) by the soil resistance to loads. The second parameter is taken from a specialized table. It is given in kilograms per cm2. taking into account the level. For soft loams, for example, use the value: 3.5 units.

The correction factor is more difficult to determine:

• From 1.1 to 1.2 are used if the composition of the soil is determined using a comprehensive geological survey of the site. The corresponding task is entrusted to a specialized organization. Its specialists take samples at several points down to the depth of hard rock, which are tested in laboratory conditions. You will have to spend some money and time, but you will get the most accurate result.
• The second method is simpler and cheaper. A drill is used to measure dynamometer characteristics as it is immersed in the soil. If such a technique is chosen, the correction factor is set at 1.2-1.25.
• In the next option, you should increase it to 1.35-1.4. Here you will need to dig holes yourself. The soil at the final installation depth of the screw part is checked independently. For example, you can measure sand fractions and then select the appropriate soil resistance from the table.

If the site has weak soil (swampy, watery sand, peat bogs), and the load on the foundation is expected to be high, the most reliable foundation for a house is a pile foundation.

In addition to reliability, a pile foundation has another important advantage: undemanding to the terrain. There is no need for careful leveling of the construction site. This greatly simplifies the process of installing a pile foundation with your own hands and reduces environmental damage to the surrounding landscape.

What types of foundations are there on piles?

Based on the nature of their interaction with the ground, a distinction is made between hanging piles and rack piles. The former rest on the ground with their side surface and withstand the load due to friction; the latter are installed with support on hard rocks underlying looser layers.

a) pile rack, b) hanging pile. 1 - pile, 2 - weak soil, 3 - strong soil.

According to the method of immersion, piles are:

• driven - reinforced concrete, steel or wood, driven by impact directly into the ground or into leader holes;

• reinforced concrete shell piles. They are immersed using the vibration method, followed by excavation of soil from the cavities or without excavation, with or without filling with concrete;

• for the foundation. Wells are drilled in the ground, reinforcement is placed in them and concrete is poured;

1 - immersion of the casing string into the ground. 2 - Extracting soil from the casing. 3 - Immersion of the reinforced frame into the well. 4 - Filling the well with concrete. 5 - Removing casing pipes.

• screw pile foundation.

Features of foundations on screw piles

A screw pile is a hollow steel rod with a sharp tip and spiral blades. The diameter of the rod is 10-30 centimeters, the length is from a quarter of a meter to 2.5 meters.

If more is required, the pile is increased. The upper end of the pipe (heel) can be rectangular, round, or U-shaped. The pile is screwed into the ground like a screw, hence the name.

During manufacturing, the surface of the rod is coated with special anti-corrosion compounds.

The service life of a pile-screw foundation is over half a century (50 years - manufacturer's warranty).

Pros and cons of a pile-screw foundation

The main advantage of a screw foundation is the ability to do without excavation work and pouring concrete. This dramatically reduces work time and energy consumption:

• no need for a concrete mixer or a large amount of material - concrete itself, reinforcement, ;
• no need to wait for the foundation to gain strength;
• no heavy equipment required. For small structures, the piles can be screwed in manually.

The exception is combined pile-strip foundations. When constructing them, you cannot do without concrete (sometimes brick is used instead, but this increases the energy intensity of the work).

Under a heavy brick house you will need a concrete strip or reinforced concrete belt.

In other cases, the piping of a pile-screw foundation is made of metal beams, for light houses -.

A) The foundation option is suitable for the construction of a frame, wooden block and brick house. B) The foundation option is suitable for the construction of a frame, wooden, block and brick house. C) The foundation option is suitable for the construction of a wooden house. D) The foundation option is suitable for the construction of a frame, wooden, block and brick house.

If the grillage is metal, the only way to connect the foundation parts is welding. If you have the appropriate equipment and skills, this greatly simplifies the process of building a foundation for a house.

Concrete is also needed when constructing a screw foundation: it fills the hollow cores of the piles themselves. But the amount of material and scope of work are not comparable to the construction of reinforced concrete structures.

Note!

The construction of a pile foundation of this type is possible on all soils except rocky ones, incl. on flooded soils.

The length of the rod can be chosen so that the pile passes through the unreliable soil and is secured in a stable layer.

• screw piles are used for private development and for small-sized structures. High-rise buildings with a large mass are not built on them;
• When screwing a pile, it is impossible to control its passage through the soil. Solid inclusions contained in the ground can damage the anti-corrosion coating;
• in the absence of a reinforced concrete base, arrangement of the basement floor is problematic;
• settlement of piles is uneven, highly dependent on soil characteristics within one area;
• despite the lack of excavation and concreting, the prices for a pile-screw foundation are significant due to the cost of the piles themselves.

Calculation of foundations on screw piles

To determine the required number of piles, you need to divide the total pressure on the ground by the load-bearing capacity of the pile.

The calculation of a pile foundation is carried out in three stages:

1. The total load is determined - the total weight of the structure, including floors, internal walls, furniture, roof, people and all the contents of the house. According to SNiP 2.01.07-85 for private houses, the payload is 150 kilograms per square. The snow load should also be added here. It depends on the region (for example, in the north of the Moscow region - 240 kilograms per square). The total value is multiplied by a factor of 1.2.
2. Additional loads are taken into account - wind force, etc. Typically, the safety margin is 30% of the design figure.
3. The bearing capacity of the soil is determined either based on the results of geological research (2.02.03-85 SNiP) or according to existing tables.

Note!

Usually, under a small private house, piles are installed with a design step of 2-3 meters.

How to make a pile foundation with your own hands?

Installation of a pile-screw foundation begins with markings. The corners of the structure are marked, and a marking cord is pulled between them. The immersion points of the piles are marked with pegs in accordance with the calculated step.

The piles are immersed at the marked points. At a immersion depth of up to one and a half meters (freezing level in the middle zone), this can be done manually.

If the depth is greater or the soil in the area is very dense, special equipment is used for screwing.

• align the piles in height (tighten some, cut others);
• fill the cavities with concrete mortar;
• install grillage.

Price of foundation on screw piles

The price of a screw foundation depends on the length of the piles, cross-section, and wall thickness. The cost of a screw pile for a foundation is influenced by its design features: reinforced tip, reinforced blade.

Approximate prices:

• pile 5.7 cm (for gazebos and other lightweight structures), steel thickness 3.5 mm, length 1.5 meters - from 800 rubles, immersion - from 1.2 thousand rubles;
• pile 8.9 cm (and), thickness 3.5 mm, length 2 meters - 1.1 thousand rubles, immersion - 1.4 thousand rubles;
• pile 13.3 cm (for a private cottage), thickness 4 mm, length 3 meters - from 2 thousand rubles, immersion - from 1.8 thousand rubles.

The cost of a pile-screw foundation also includes the price of grillage materials and its installation.