A house made of timber on screw piles: tips and tricks for creating a project. Foundation on screw piles for a house from a bar Project of a house from a bar on stilts

Everyone wants to build for centuries, so that children and grandchildren can enjoy the family nest. But a house made of timber will not last long if you are careless about the choice of materials for building the foundation. Screw piles provide an ideal combination of price and quality. Read below what you should pay attention to when choosing them.

Decided to build a house out of timber? Great choice! An ideal foundation for your building will be a pile-screw foundation. Firstly, its use significantly expands the possibilities when choosing a place for a log house, since the relief and geodesy of the site are not afraid of steel supports. Secondly, the zero construction cycle will take place in

the shortest times. After all, the installation of screw piles takes a little time, and installation can be carried out at any time of the year (even in winter!), At the same time, without compromising the quality of the foundation. By the way, wood harvested during the cold period has a lot of advantages. Most importantly, in winter it is freed from excess moisture.

“A pile-screw foundation is perfect even for a site with large differences in ground level”

Please note that the landscape affects the calculation of screw piles for a house made of timber in only one case - if the ground level difference is more than 70 cm. You will need to strengthen the foundation, that is, additionally tie it with a channel that will strengthen the pile field.

An example of strengthening a pile-screw foundation for a log house built on an uneven site

The choice of screw piles will be affected by the weight of the future building. Note that the wider the support shaft, the more load it can withstand. The standards allow the use of steel supports with a diameter of 89 mm in capital construction. However, it is not worth agreeing to install them under a log house in order to avoid the collapse of the foundation. Having many years of experience in calculations, design experts recommend using supports with a diameter of 108 mm, while a barrel wall thickness of 4 mm is considered quite reliable. Do not forget that during installation, the piles are poured with concrete, which additionally strengthens them from the inside.

If you want to be sure of your foundation not by 100, but by 200 percent, then use screw piles with a diameter of 133 mm to build a house from a bar. It is worth emphasizing that this is not necessary, since the construction is relatively light. As a rule, timber with a diameter of 150 - 200 mm is used for housing construction. In this case, the weight of a linear meter of the wall is approximately 2-3 tons. According to the standards, each screw pile with a shaft diameter of 108 mm can withstand a load of 4-5 tons. So, you will still have a large supply for the installation of furniture, household appliances and friends invited to the housewarming party.

“When choosing piles, do not save on diameter! For a log house, choose 108 mm”

The blade of the product also affects the bearing capacity of the screw pile. Taking into account the peculiarities of the soil of Moscow and the Moscow region, the recommended diameter is 300 mm with a steel thickness of 5 mm. The required number of screw piles under the house from

timber, their length, and, accordingly, the final price of the foundation, can be calculated based on the area of ​​\u200b\u200bthe building. The specialists of our design department will help you with this, if you have a house plan.

The project of a house from a bar on a pile-screw foundation

Pile-screw foundations are cheaper for a house made of timber than concrete ones. As for their service life, it depends on the quality of steel, production technology, as well as a protective anti-corrosion coating. The better and more modern all of the above, the longer the foundation will last.

“Give preference to piles with high-quality anti-corrosion coating and entrust the installation to professionals”

In conclusion, it is worth saying that it is better to entrust the installation of the foundation to professionals. This will save you time and effort on this time-consuming manual assembly process. Do not forget that professional teams use specialized

equipment. Electromechanical installation ensures high-precision installation of screw piles with minimal deviation. In addition, you will receive a guarantee for the foundation from the manufacturer.

First you need to decide on the choice of foundation for a house or other building. We are interested in building a house from a bar. Based on the fact that it does not have a lot of weight, the foundation may not be expensive. Before the start of construction of any building, a project is created according to the building site. Of the several possible options for the foundation, you can stop at the pile structure. Whether it is reliable to install a house from a bar on piles, we will consider in our article.

One of the types of foundation for a house made of timber is a pile structure. Pile foundations are classified into several types:

• stuffed - a special machine drives the pile to a certain depth;
• drilling - a drilling machine or a hand drill drills holes into which piles are installed;
• screw - screwed into the ground manually or mechanically, the pile has a tip in the form of helical blades that make it easy to work.

For houses made of timber, any type of pile foundation is applicable, but the most popular, if you look at consumer reviews, is a screw pile foundation.

• It consists of metal hollow pipes of different diameters and lengths. The lower part of the pipe has helical blades that allow the pipe to go deep to the desired depth. At the same time, the soil is not loosened, but compacted, which has a positive effect when installed in low-lying places, with a close location of groundwater, sand, and peat.
• The binding of the pillars can be made with a beam or metal elements (I-beam, channel) so that the structure does not part.
• The pile foundation is installed on any soil and terrain except rocks. Even slopes and differences in soil level are not a hindrance to the construction of a structure on piles. It is only necessary to adjust the height of each pile during installation, twisting to different depths.
• The basement depends on the purpose. If it is supposed to equip the cellar, the base is made as high as possible, in other cases it reaches 400–500 mm from the ground.

How to calculate the number of piles for the foundation?

When designing a house, the required number of pile columns is applied on the plan. Their number depends on:

• type of material (section of timber, moisture content of wood);
• the size of the house along the perimeter;
• number of floors, attic;
• structure weight;
• results of geodetic studies of the soil;
• climatic conditions of the region.

If it is incorrect to calculate the number of piles for a house at the time of design, problems may arise during operation - an uneven floor, sagging elements, or a skew of the entire structure. It is recommended to install posts every 1500–3000 mm around the perimeter and at the junction of adjoining walls. The calculation is made according to a certain algorithm:

1. The total volume of material (beam, cubic meters) is taken into account.
2. Multiplied by the weight of one cube = 800 kg.
3. The payload of each floor is added (multiplied dimensions of the log house with a factor of 150).
4. The snow load of the building is the derivative of the walls of the log house, multiplied by the coefficient. 180.
5. Multiply the resulting amount with the coefficient. reliability =1.1.
6. We divide the result by the weight load that one pile can withstand, we get the total number of piles for a house made of timber.
7. Consider an example of a one-story 8x6 structure from a 150x150 bar.

• 21.6 * 800 \u003d 17,280 kg .;
• 8*6*150=7200 kg;
• 8*6*180=8640 kg;
• 17280+7200+8640=33 120 kg;
• 33 120 * 1.1 = 36 440 kg - the total load of the building, taking into account all parameters.
• For the foundation, we take a pile with dimensions: 89x250x2500, which can withstand weight up to 2 tons.
• 33 120/2000=16.56. This means that 17 screw piles are required for the foundation.

How is the construction of a house from a bar on screw piles

1. There is no need to clear the site for the foundation.
2. We apply the markup according to the plan.
3. In the marking places, we install piles, screwing in to a certain depth, but not less than the depth of soil freezing. Usually the screw goes up to 1500 mm or more. On the surface, the pipe remains 400–500 mm high. With level differences (slopes, ravines), the height of the protruding part is measured by the level.
4. When screwing screw piles, special equipment is used, or work is performed manually. The number of people to install one pillar is a multiple of three to five: two or four twist, one controls the process.
5. After screwing in all the pillars specified in the project, they must be poured with concrete if the house from the timber is installed for permanent residence. In the case of a temporary structure, it is possible not to pour concrete into the cavity of the pipes.
6. From above, a head is welded to each pole, on which a strapping from a bar will be mounted. Often, the strapping is performed with metal elements, welding a channel or an I-beam around the entire perimeter. The main thing is that the design is stable.
7. Do not forget to treat the piles with anti-corrosion impregnations to extend the life of the foundation.
8. The next step will be laying out the first crown of the house from a bar.

Projects of houses made of timber on piles are presented in the photo of the Internet space in a large assortment. Choose the one that suits you or create a unique project. When choosing a project for a house made of timber on piles, do not forget that the foundation is designed for lightweight structures. It is impossible to build a multi-storey building without observing certain rules:

• correct calculation of the number of piles on the foundation;
• if possible, choose lightweight materials for the roof and log house;
• take into account the characteristics of the soil;
• correctly tie the pile foundation;
• to treat metal against corrosion;
• entrust the installation to specialists.

When considering projects of houses made of timber on piles, do not forget to look at the reviews of people who have become owners of such houses. Mostly, the reviews are positive. Satisfied are those who dreamed of building a reliable house on soils not intended for mounting a house on other foundations. Positive feedback on construction forums from people who want not to delay construction for a long period. The pile screw foundation is installed in a few days if the work is carried out by specialists. But there are also reviews of those developers who decided to independently screw the piles under the house from a bar. The results are good. A pile screw foundation for a small private house made of timber can cost as little as 35,000 rubles and more. It all depends on the size of the structure. Here is a table of the cost of a pile foundation for some typical projects of houses made of timber.

The average price for a pier foundation for a 6x6 project from a 150x150 bar will be about 50,000 rubles. If you also dream of a new home, take a closer look at the projects of a house made of timber on stilts. Such projects are cheaper than similar options on a strip or column foundation.

Despite the development of construction technologies, including the creation of new modern building materials, many developers prefer the good old wooden buildings. Houses made of logs and timber are as popular as they were a hundred or two hundred years ago, especially since their modern counterparts have stepped forward significantly compared to traditional peasant huts. Technologies for building foundations for houses from timber are also developing. The best option can be considered a foundation on screw piles.

1. Design features of timber houses

Log houses, in particular log houses, along with stone houses served as the first buildings for human habitation since time immemorial. It can be said that the technology of log buildings has not changed much since then, except that today progressive technologies of building from glued beams are successfully used, the possibilities of high-quality rounding of logs have appeared, house designs have become more complicated, and the houses themselves look very attractive thanks to modern projects of their construction. Compared with other building materials, wood has a number of properties that determine its use for the construction of residential buildings for any purpose:

• Environmental friendliness
• Good thermal insulation
• Compliance to processing

As for the massiveness of houses, this parameter is in the middle between heavy stone or brick houses, houses made of cinder blocks and light frame buildings. As a rule, in terms of weight, houses made of timber are comparable to buildings made of foam concrete and gas blocks. This is due to the porous structure of wood, similar to the structure of foam building materials.

A relatively simple technology for building log houses also plays its role: its walls are built from a series of logs, the so-called crowns, along the perimeter of the building, including internal walls and partitions. The construction of a "box" of logs does not require the use of a significant amount of concrete work and fastening work. Not without reason, the architects of antiquity could build huge towers with the help of an ax alone.

As for the foundation for log houses, they were also built from the hardest wood in the past. Since then, the technology of laying foundations has come a long way. The main requirement for the base of the house is to securely hold it on the ground, so that distortions do not occur during operation - this is especially important for wooden houses, because their design consists of interconnected elements.

As it was said, the weight of houses made of timber is inferior, with equal parameters, to the weight of stone and brick houses. Consequently, the foundation for timber houses may not be as strong, which generally reduces the cost of construction.

2. Advantages of a pile-screw foundation for a house made of timber

Traditionally, several types of foundations are used for log houses:

• slab
• Tape
• Columnar

It should be noted that the creation of monolithic foundations for any structure is fraught with some difficulties:

1. High labor intensity
2. Cost
3. Long commissioning times
4. Instability on soft soils, watered and heaving soils

In recent decades, the technology of laying foundations on screw piles has been rapidly developing. It is pile-screw foundations that are devoid of these disadvantages, and their use as foundations for timber buildings has a number of advantages over traditional types of foundations:

• Saving money
• Speed ​​of erection
• Lack of earthworks associated with the loss of soil useful for agriculture
• Possibility of construction on "problem" soils
• All-season work
• Ease of establishing communications in the house compared to other types of foundations
• Ease of erection
• Lack of special preparation of the place for the foundation
• Bookmarking in areas with elevation changes
• Possibility of erection with dense development of the site

3. Features of laying a pile-screw foundation for a house made of timber

What additional requirements may arise for the foundation on screw piles for a house made of timber compared to those for the construction of other types of structures? Obviously, they can be associated with the design features of the timber buildings themselves.

Unlike frame houses, the walls are built from monolithic elements - logs laid horizontally on the ground. Thus, the weight of the roof is transferred to individual logs, and then from the upper logs to the lower ones. Thus, the main weight load is distributed evenly throughout the lower crown. In frame houses, the main loads fall on the racks, that is, they act pointwise along the wall.

Unlike brick and block houses, a wall made of timber is not monolithic and the loads on the lower bars are not so evenly distributed around the entire perimeter of the house.

This is due to the fact that the weight of each log in some part of it may differ from the average - this is due to the uneven density of the wood used, deviations in its thickness, etc.

If for a frame house it is necessary to tie the foundation on supports, and monolithic houses are placed immediately on a monolithic foundation, then in houses made of timber, the lower crown itself can serve as a foundation tie.

Thus, the main feature of the construction of the foundation on screw piles is the possibility of laying the lower crown directly on the piles. However, the lower crowns of different walls are at different levels - two perpendicular rows are laid on two rows of logs. Consequently, only two of the four lower logs of the crowns are laid directly on the pile heads. Accordingly, the other two logs should lie on the strapping.

But the installation of logs on piles should be based on flat areas - this adds requirements to the mandatory equipment of the end of the piles with special heads.

Another requirement for the foundation on screw piles is its sufficient bearing capacity. Although the weight of log houses is inferior to the weight of brick counterparts, it is usually quite large compared to the weight of frame structures. This predetermines the use in this case of screw piles with increased dimensions, as well as with a greater depth of their screwing.

4. Installation of a pile-screw foundation for a house made of timber

In general, the construction of a foundation on screw piles for timber houses is not fundamentally different from laying a foundation for frame houses. First of all, it is necessary to make a calculation of its bearing capacity - this will determine which piles can be used, what will be the step of their installation, and to what depth they will need to be screwed.

The dimensions of the house and the financial capabilities of the owner predetermine the use of heavy equipment or manual labor to lay the foundation.

Standard houses made of timber for permanent residence are usually placed on screw piles with a diameter of 108 cm or more, with a pipe wall of at least 4-5 mm. Accordingly, the blades in the general case have a width of at least 25-30 cm, and the depth of screwing the piles depends on the existing soil properties and is usually 2-2.5 meters. Thus, the use of 3-meter piles with a diameter of 108 mm is considered optimal.

If a lighter structure is being built from logs, for example, a small bathhouse or a gazebo, then, accordingly, the diameter of the piles can be reduced, as well as their deepening.

The course of foundation construction in the standard case consists of several main stages:

1. Calculation and planning
2. Foundation site preparation
3. Pit drilling to facilitate pile driving
4. Pile screwing
5. Cutting piles by level
6. Pile concreting
7. Creating a harness

5. Tying a pile-screw foundation under a beam

As we mentioned above, structurally the lower crown can serve as a foundation strapping. In the case of using a beam with a rectangular section, it is enough to screw the lower beams to the pile heads. Some difficulties arise with the use of cylindrical logs - after all, they must fit snugly against the base.

In this case, builders use a number of techniques.

• Firstly, for additional rigidity of the foundation, screw piles are equipped with a grillage made of metal beams or channels welded to the body of the piles.
• Secondly, only two lower parallel logs are placed on the pile heads. Perpendicular logs can be laid on additional lower beams not connected to the frame

6. Conclusion

Installing a foundation on screw piles is the best option for laying the foundation for houses made of timber, even houses for permanent residence that have large dimensions. For such foundations, it is better to use the services of specialists - they will be able to correctly assess the properties of the soil, calculate the parameters of the foundation and carry out high-quality installation of screw piles. If a small building is being erected, especially in the cramped conditions of an already built-up area, then it is quite possible to use the manual method of installing screw piles and make it yourself.

Accurate calculation - this is the main theme that sounds after the decision to build a house. A correctly made calculation will allow you to choose the best version of the future structure from a large number of them offered on the market. Everything can be foreseen in advance: dimensions, number of storeys, materials, and their environmental friendliness, as well as the cost of work.

It is no coincidence that houses made from natural materials are gaining popularity. The use of timber for the construction of cottages is justified, including safety for the health of its inhabitants. Also, special requirements are imposed on the choice of foundation. The construction and price calculation shows that the pile foundation for a house made of timber is sufficient to withstand the loads, and is less burdensome for the financial part of the construction.

This option causes a number of reasons, of which only a minor part is unacceptable. Only the type of soil on the construction site can exclude the use of a pile foundation, the advantages of such a choice will be discussed below.

Options for foundations for a house made of timber

Any capital construction structure needs a foundation, and the stronger it becomes, the easier it will be in terms of repairs to operate the object after construction. However, there is a principle of sufficiency. There is no need, for economic reasons, including, to arrange a massive foundation, with a significant reserve of the safety factor, where you can get by with the same a solid foundation while saving money.

At the design stage, each of the existing foundation options is considered, and the final choice is made taking into account the soil at the construction site, the load from the structure, the customer's wishes in terms of architectural nuances, commissioning dates and, of course, cost.

Tape, the most common option, its popularity is due to the ability withstand and "dissipate", with proper calculation, large loads, even from two-story structures made of heavy timber. The simplicity of the construct of such a choice turns into relative simplicity during construction. In fact, after reading about this option, or after consulting with experts, even a novice in construction can build it, however, with very high labor costs.

Exists two types of strip foundations:

• buried;
• shallow.

The shallow view allows reduce the cost of construction, due to the smaller, in comparison with the more capital type, the volume of earthworks, the consumption of building and related materials. The efficiency and applicability of such a foundation becomes hostage to such a choice.

A prerequisite for its use is favorable geological conditions- low groundwater level, construction is carried out on non-heaving soils. The weight of the building is also limited with this choice. Otherwise, the results of the work will not be used for long.

Recessed view avoids the limitations of the first type of base, respectively, and all types of costs will increase. The volume of excavation, by the way, the most expensive work, will grow significantly, and the cost of purchasing cement, sand, crushed stone, rebar, wood for formwork will also increase. Financial losses are not the only ones. For the qualitative arrangement of this foundation, a large time delay will be required. In some cases, the foundation is required defend up to a year, then to continue construction.

Slab variant doubles the disadvantages (in terms of finance) of the above options, but has one indisputable advantage. He is not afraid of seasonal swelling of mobile, heterogeneous soils. It is extremely difficult to build such a foundation with your own hands, without the involvement of specialists.

Solution

To avoid the disadvantages of the above options allows the choice of pile foundation. This option known in construction for a long time, but mass use began relatively recently.

Pile-screw foundation avoids:

The ability to resist loads is not inferior, if not superior to the more familiar base options, a pile foundation for a house made of timber will be able to ensure the integrity of the structure during operation. Plus adds the ability to build up the foundation of piles at any time. This may be necessary for completion, for example, a terrace. Access under the house for maintenance lightweight and eliminates floor rotting under the influence of external circumstances.

Driving screw piles

So, the result of geological surveys made it possible to realize a double saving at the stage of foundation construction, the designers calculated and chose a pile-screw foundation. It's time to start implementing.

Area set up, getting ready pits for the initial installation of piles with a depth of a meter to one and a half. Further, in accordance with the project, the first pile is installed. It is leveled and after several turns the installation angle is checked again. Screwing is done manually or mechanically. For very light structures, it is enough to insert crowbars into the technological holes, build them up with pipes, and such an impromptu lever will allow you to twist the pile to the desired level.

For capital construction, it is better to use mechanisms. An excavator with a hydraulic drill will perfectly cope with this task, and an experienced driver will check the pile foundation for the reliability of its installation. The first pile is screwed in, it is immediately cut to size. She will become a rapper. Checking the installation of the remaining parts of the pile field is carried out, focusing on this center of the local coordinate system.

The pile foundation for a house made of timber is ready.

The following actions

When the pile foundation field is made, you can proceed to the next step. Tying a pile screw foundation additionally strengthens the structure, is made of a channel, an I-beam, a wooden bar, a coupler. Tying with a bar is the least expensive method, which, nevertheless, is able to give sufficient rigidity to the structure.

Tying the foundation of modern components is often used in the construction of houses and baths from wooden beams. Technologically produced binding of the screw foundation with a bar will ensure the absence of distortions and a long life of the structure.

To do this, you need to follow a few rules. The work is being done under the indispensable condition of leveling all piles in one level. Otherwise, it will have to be leveled by sawing in the right places the timber itself to the desired depth. Also, practice prescribes to carry out the strapping almost “immediately” after the installation of the heads, this will avoid trouble with a violation of the work technology.

For docking, in it cuts are made at the ends. The first is from above, the next from below. Further, the beam is laid at a right angle, the connection surfaces must be strengthened with a moisture-resistant wind-proof material, such as jute.

The article will tell about the design and construction of houses from timber on screw piles.

Wooden houses are popular among private developers and owners of summer cottages. They are environmentally friendly, as they are made from natural materials, endowed with their own unique aesthetics.

Among all wooden building materials, the most popular is timber, the advantages of which are:

Availability. The construction of a log house will not require large investments, including due to the price of the material itself, as well as the manufacturability of the construction process.

Speed. You can assemble such a structure within a few weeks. Additionally, the terms are reduced if factory kits are used.

Environmental friendliness. Burs is a natural material that allows you to naturally regulate the humidity and temperature in the room, making living more comfortable. In addition, wooden walls make the room more comfortable.

No interior decoration required.

Thermal insulation. In winter, a house made of timber is perfectly protected from the cold. In summer, it also maintains a comfortable temperature, as the walls do not heat up.

Of course, the structure of the timber and the shortcomings are not devoid of:

Fire hazard. The use of wood in construction increases the risk of fire. At the same time, it is simple to solve this problem, it is enough to treat the walls with special compounds.

Wood aging under the negative impact of external factors. Humidity, insects are the main enemies of a house made of timber. But they can also be dealt with with the help of antiseptics and other special substances. And to create additional protection against water, the walls can be sheathed from the outside, for example, with siding.

To build a house from a bar in one season and avoid increasing construction costs, it is enough to use screw piles as the basis for it. Of course, in order for the quality of the construction to be at the proper level, it is necessary to pay enough attention to the design of the foundation.

Determination of the ground conditions of the construction site

What role does the foundation of a building play? Of course, it transfers the loads from the building/structure to the foundation of the soils below it. Therefore, when developing a foundation project, it is very important to rely on accurate data on soil conditions. Without this, either an unreasonable rise in the cost of the foundation structure will occur (due to the use of a solution with an excessive margin of safety), or risks will arise that cannot be calculated without geological research.

So, surveys at the site make it possible to identify many dangerous geological objects and processes:

suffusion;

• swimmers, etc.

If you do not know about them, you can expose everyone living in the building to a rather serious danger.

In addition, even within a small area, different conditions of soil occurrence can occur, which also needs to be taken into account when designing, and which cannot be known without appropriate research.

In the case of a screw pile foundation, soil data are of fundamental importance also because they are taken into account when selecting absolutely all parameters of screw piles, each of which plays an important role.

The corrosive aggressiveness of soils (CAG) of the construction site affects the designation of the steel grade (more details ""), the thickness of the wall of the barrel and blade (more details ""). As a result, the service life of the building complies with the requirements of regulatory documents (GOST 27751-2014).

After performing the lifetime calculation, during which the metal losses during operation are determined, the residual wall thickness of the shaft must be checked for compliance with the design loads. And after the screw piles are immersed, a control measurement of the torque value (VKM) is carried out. This is not an independent study (as well as test screwing, in which the VKM is also indirectly determined), but only a procedure that allows you to confirm information about soil conditions.

All the information necessary at the design stage can be obtained if simple procedures are carried out - geological and lithological surveys and measurements of the corrosiveness of soils (more details ""). Studies are specially adapted to the needs of low-rise construction.

Collection of loads from the structure

In order to correctly determine what bearing capacity of the foundation for a house made of timber is necessary, it is important to carry out the collection of loads, that is, to take into account different types of impact.

permanent loads (weight of parts of the structure);

temporary influences (weight of people, furniture, wind/snow loads).

Only summing up these indicators, you can get the correct figure. Otherwise, the actual weight of the structure will be greater than the calculated value, which in the future will give a guaranteed subsidence of the foundation.

Grillage of a pile-screw foundation for a house made of timber on screw piles

Detailed information about the types and methods of grillage installation can be found in the "" section. Technical solutions for the plinth are published in the "" section.

The foundation for a log house is always calculated individually. So that we can calculate its cost for you, provide data about the object (wall construction, number of storeys, etc.) and geological survey data or sign up for a visit by a geologist.