). A small consumption of building materials, minimal earthworks and the ability to do without special equipment can save a lot of money.

To give the structure strength and reliability, free-standing supports are combined into a single rigid system using a grillage (). This is the binding of the foundation, designed to evenly distribute the load from the building to the ground.

By location relative to ground level, the strapping can be:

• buried - immersed in the ground in such a way that its upper face is on the same level with the ground;
• elevated - lying on the ground;
• high (hanging) - raised above the ground by 150 mm or higher.

The latter option is used on heaving soils. The first - buried - is used extremely rarely and only on inactive soils.

Depending on the materials used, there are four types of tying pile foundations:

• channel;
• I-beam;
• reinforced concrete monolithic tape;
• bar.

The metal strapping is highly durable, but it is very difficult to mount it without a truck crane.

Reinforced concrete grillage is stronger than metal grillage. It can be built on your own, but the labor costs for its arrangement are high. In addition, the construction time is being delayed: work has to be suspended until the concrete gains the necessary strength.

When building private houses from light building materials, it is quite possible to get by with a beam: wooden piping is cheaper than metal and reinforced concrete, it is quickly mounted and has sufficient strength.

Features of tying piles with timber

As a starting material, you can use a beam with a section of 150x200 mm or boards 50x200 mm, assembled into a composite beam. With a distance between supports not exceeding 2.5 meters, such a structure can easily withstand the weight of a two-story frame-type building.

The lower trim of the frame house on screw piles simultaneously plays the role of an intermediate link in fastening the walls of the structure to the foundation. Consequently, the responsibility for the uniform distribution of the load lies with it. Therefore, it is especially important to avoid uneven height of the screws.

If such an incident happened, and the beam hung in the void above one of the piles, the situation can be corrected by hammering a wooden gasket into the void through the waterproofing layer.

But it is better not to allow such a problem in the first place.

Video about the types of tying the foundation on screw piles.

The screw pile foundation remains one of the most popular solutions for individual construction due to its affordability, simplicity and stability, even on “floating” soils. However, in order for your home to be even more comfortable and not require repairs for as long as possible, it is necessary to make its foundation even stronger and more durable. For this, operations such as tying and closing screw piles are performed.

Inexperienced builders often confuse tying screw piles with closing the foundation. Although these two stages of the process of building the foundation of a house are connected in some way, they serve slightly different purposes.

strapping involves combining the heads of screw piles already installed in the ground into a single structure along the entire perimeter of the foundation and along the contour where the internal walls of the structure will be erected.

The lack of strapping, which is done using timber, boards, channel bars and other materials, will lead to an uneven load on each pile. The consequence of this will be the rapid destruction of the foundation, which will simply “float”.

Closing screw piles gives the building a more aesthetic appearance and minimizes heat loss. After all, since the foundation is not and there is open space under the house, the floor in such a building is unlikely to be warm enough.

For closing use a variety of modern materials.

Strapping options

Tying piles with timber

Owners of relatively light buildings - wooden or frame-panel - should give preference to this particular type of strapping. A grillage made of timber cannot be called very durable, but for such construction it is the most suitable and affordable option.

Often, a bar made from coniferous wood is used for strapping, since its cost is several times less than similar products made from hardwood, and the differences in performance are minimal.

Before installing the grillage, special antiseptic compounds must be applied to the timber to prevent the destruction of wood under the influence of atmospheric factors, and covered with a bituminous waterproofing layer. The latter gives the timber water-repellent properties.

When tying a pile-screw foundation with a bar, do the following:

The pile head is mounted after the pile is leveled (cut) and after concrete is poured inside it (if necessary).

1. Carefully align the installed piles so that the pillars are exactly at the same level.
2. Heads are mounted on piles.
3. Perform waterproofing material.
4. On the beam, which falls at the joints of the corners of the house, grooves of the required size are cut out for the subsequent connection of the wooden parts to each other.
5. The timber is laid out on the pile heads along the perimeter along the entire contour of the foundation in such a way that the joints of the separate parts of the grillage are fastened together on the heads. At the same time, the joints are laid with a bundle for better sealing.
6. Align the grillage and carefully check the angle: it should not deviate from 90 degrees.
7. The beam is fixed on the pile heads with self-tapping screws.

Tying piles with a board

When installing a pile foundation, the strapping with a board has a number of indisputable advantages compared to a beam:

1. When carrying out work cracks may appear in a beam with a too large cross section or it is significantly deformed.
2. For making beams a beam longer than 6 m is not suitable because of the serious problems that may arise with this.
3. Beams from a bar are quite heavy, so for their installation will require a whole team of workers. At the same time, a beam of boards is made right next to the foundation, which is much easier.
4. Beams from boards do not require additional drying and are distinguished by increased strength in comparison with analogues from a bar.

The binding of screw piles using boards is performed according to the following algorithm:

There is another way to tie a board. The boards are glued together and additionally fastened with screws and nails. With a small thickness of the boards, you can lay them with plywood for greater strength. During installation, it is important to separate the joints of the boards into different piles and use the proven “half-tree” method.

Binding of piles with a channel (I-beam) or corrugated pipe

Metal grillages make it possible to use a pile-screw foundation in the construction of not only wooden buildings, but also buildings made of cinder blocks, foam concrete and gas silicate on one floor.

Sometimes, instead of a channel, an I-beam is used, which is highly resistant to compressive loads and provides greater structural rigidity. I-beams with a section of 20 are often used. In the case of a channel for load-bearing walls, metal beams with a section of about 30 mm are taken, for the rest - with a section of about 20 mm.

The foundation is tied with a channel or an I-beam as follows:

1. Pile columns are installed at the same height and the metal trim elements are treated with an anti-corrosion agent.
2. Metal beams are placed on piles so that they are connected in the middle of the pile columns. The channel is cut at a right angle at the corner joints of the grillage elements.
3. The beams are welded to each other and to the pile heads.

Tying a pile foundation with a corrugated pipe is carried out in almost the same way, however, the resistance of such a material to significant mechanical loads can be much less. Of the advantages of the pipe, we note the cheapness and low weight.

Piling of piles using reinforced concrete grillage

Reinforced concrete piping is almost a third cheaper than metal piping, but it has a number of disadvantages, the main ones being the laboriousness of the installation and the impossibility of continuing construction until the grillage has completely hardened. This usually takes at least a month.

When tying piles with a reinforced concrete grillage, it is necessary to proceed as follows:

What is the pile foundation covered with?

A closed pile-screw foundation is a reliable protection against rodents and other animals that can settle in the empty space between the piles. Also, the sheathing and finishing of such a base will prevent heat loss in the home and help create a good microclimate there without excessive humidity.

The most popular ways to close a pile-screw foundation:

• creation of a hinged plinth;
• creation of a shallow tape-type plinth.

For a hinged plinth, thin and not too powerful composite and polymer materials, as well as wood, are used. At the same time, the load on the screw piles is minimal, and the simplicity and speed of installation, combined with low cost, often captivates.

Any type of base finish on piles requires the presence of two ventilation holes on opposite walls of the house. This will prevent moisture from accumulating on the piles and grillage, which will not corrode or rot (in the case of wood).

However, the pile foundation will last longer with the installation of a shallow-seated strip plinth, which will be the best protection for the pile frame, guaranteeing its durability.

Thermal and waterproofing when closing the plinth

All types of plinth finishes involve the arrangement of a heat and waterproofing layer, which is covered with asbestos-cement slabs, decorative thermal panels mounted on a crate of boards or a slate slab, or bricks. All of these materials have their pros and cons:

Tying and closing screw piles is a very important stage in the construction of a house, which determines how soon it will need a major overhaul.

In contact with

Strapping (grillage) is an important structural element of any pile foundation. The classification of grillages is carried out according to three factors: the type of construction, the level of placement and the material of manufacture.

This page provides information about the technology of arranging different types of strapping. You will learn how to make a grillage from timber, channel and reinforced concrete with your own hands, and get acquainted with the video that reveals in detail the essence of the technology.

The beam grillage has a limited margin of safety, which does not allow it to be used for the construction of heavy brick buildings, however, when building light wooden 1-2-storey houses from utility rooms - baths, garages, verandas, in terms of economy and speed of installation, this is the preferred strapping option.

Rice. 1.3

The typical size of the strapping beam is 15x15 and 20x20 cm. It is recommended to use coniferous woods, due to their greater durability, in comparison with hardwoods.

Important: only a bar that has undergone chamber drying can be used for strapping, since the material with natural moisture will shrink, which can cause deformation of the walls of the house.

Before installation, the beam must be treated with an antiseptic agent that prevents wood decay, and coated with coated bitumen insulation, which will protect the material from moisture.

Technology of tying screw piles with timber:

• After installation, the supports are leveled at the zero level by trimming with a grinder;
• Heads are welded to the pile shafts. The welded joint is covered with an anti-corrosion primer;
• The surface of the head plate is covered with a waterproofing material (roofing material, glass isol or glassine);
• The beam is adjusted in size according to the length of the walls of the house (one continuous beam goes to the side of the building) and at the edges connecting at the corners of the house and at the intersections of the walls, groove joints are cut with a grinder;

Rice. 1.4

• The beam is installed on top of the pile heads, the final adjustment to size is performed. The joints between the elements of the grillage are sealed with jute;
• With the help of "wood grouses" - wood bolts with hexagonal caps, the beam is fixed on the pile heads (special holes are provided on the plates for mounting the bolt).

Tying with a steel grillage (I-beam, channel)

The strength and safety margin of the metal strapping exceed the similar parameters of the timber grillage, which allows it to be used not only for the construction of frame houses, but also for one-story structures made of foam concrete blocks.

Steel grillage according to the material used is classified into two types:

• I-beam;
• From a channel.

Rice. 1.5

Important: the choice of material must be made based on the mass of the building - a channel, due to its lower cost, is preferable for the construction of light houses, while an I-beam has better resistance to compressive loads and greater rigidity, which makes it the best choice for heavy buildings.

• I-beam tying is performed using a beam 20 cm high;
• Channel - section 30 or 40 mm.

Tying with a steel grillage is practiced exclusively when arranging screw foundations. Installation of the grillage does not require the installation of caps on the piles, the material is welded directly to the support shaft.

Rice. 1.6

The technology of tying screw piles with a grillage from a channel:

• Upon completion of the installation of the foundation, the pillars are aligned at the zero level;
• The dimensions of the grillage parts are measured, the channel is marked and cut into sections of the required length;
• Rolled metal is treated with 1-2 layers of anti-corrosion primer;
• The channel is installed on piles and cut off with a grinder at the junction at an angle of 900;
• The grillage is fixed on piles by welding. Upon completion of the fasteners, the welds are coated with a primer.

Binding with reinforced concrete grillage

A tape grillage made of reinforced concrete is used for tying bored and driven piles. It is suitable for the construction of heavy brick and foam concrete buildings with a height of 1-3 floors. In terms of arrangement, this is the most time-consuming tying option, but its cost is lower than that of an I-beam grillage.

Important: reinforced concrete grillage is subject to mandatory reinforcement, which is carried out by a spatial reinforcement cage, consisting of 2 longitudinal reinforcement belts connected by transverse and vertical jumpers. The step between the jumpers is 20-30 cm. These can be pieces of reinforcement welded with a rectangle or clamps curved into the appropriate shape.

Rice. 1.7: Scheme of reinforced concrete grillage

Corrugated rods with a diameter of 12 to 18 mm are used to assemble the frame. The grillage body is made of M300-M400 grade concrete with crushed granite filler.

Technology of binding with reinforced concrete grillage:

• The trunks of concrete piles are leveled at the zero level using a grinder with a diamond wheel, a hammer or a special hydraulic chipper - a pile cutter. Only the concrete of the piles is destroyed, while the protrusions are left intact;
• Along the perimeter of the piles, sand filling is arranged (up to the level of the trunks), on top of which the lower wall of the formwork is laid. Next, the side walls are installed, after which the structure is strengthened with stops and jumpers that tighten the walls along the upper contour;
• The formwork is lined with waterproofing from the inside;

Rice. 1.8

• The frame is being assembled - the reinforcement is joined by welding or wire. The finished frame on special fungus stands is installed inside the formwork and welded to the rods protruding from the piles;
• The grillage is concreted, after pouring the concrete is compacted by vibrating or bayoneting with reinforcing bars.

Rice. 1.9

It takes 25-30 days to set the design strength of the grillage, after which you can begin to raise the walls of the house.

Features of strapping

When tying piles, it is necessary to correctly choose the level of its placement, according to which reinforced concrete grillages are classified into:

• hanging;
• Ground;
• In-depth.

Rice. 2.0

In conditions of stable soil, the easiest way to arrange the strapping will be a ground grillage, which is located on the surface of the soil. Piles with a ground grillage are classified as a pile-strip foundation - this is a reliable foundation with a high bearing capacity, which is achieved by increasing the bearing area of ​​the foundation with a tape in contact with the ground.

However, in soil prone to heaving, this tying option is not applicable due to the risk of separation of the grillage from the pile shafts by pushing loads. Here it is necessary to equip a hanging grillage, raised above the ground to a height of 20-40 cm.

In-depth grillage - a structure that is placed in the thickness of the soil. Under the supporting sole of the grillage, the soil is replaced with a sand and gravel cushion that is not subject to heaving. Such a grillage is used in the construction of heavy multi-storey buildings, for which the safety margin of the hanging strapping is not enough.

Video of tying the pile foundation

Check out the video, which demonstrates the technology of tying piles with grillages of various types.

Video #1: Tying piles with timber

Video #2: Piling of piles with a channel

Video #3: Tying piles with reinforced concrete grillage

We carry out work

Our company provides pile driving and sheet piling, to contact us about these services, use the form below.

The tying of screw piles with timber should be carried out in full compliance with the technology at each operation performed, because the quality and reliability of any columnar or pile foundation depend on this. How to do it yourself correctly will be described below.

Screw piles are necessary directly for the construction of the foundation.

What is a screw pile and why should it be tied?

This is a column type element that is screwed into the ground. Usually it is made in the form of a metal pipe, to one of the ends of which the blades are welded. They are designed not only for immersing the screw post into the soil, but also for the correct and uniform distribution of the entire mass of the structure over the soil area.

After mounting all the supports, they are connected using beams. The resulting rigid frame structure is called a strapping (grillage).

The strapping plays the role of an overlap between the main structure of the building and the foundation. This frame structure allows you to evenly redistribute the weight of the log house on all supports. The grillage allows you to remove the negative impact of the environment on the structural elements of the building, as it is made strong enough and protects from moisture.

How to choose the right timber?

It is usually obtained by cutting a tree trunk from four sides along its entire length. It is often used in the construction of baths, log cabins and other wooden structures. During construction, timber from coniferous trees is most often used, since they have the following advantages over hardwoods:

It is necessary to carefully select a quality timber for strapping.

1. Durability.
2. High service life.
3. Relatively low moisture permeability.
4. Lower price compared to deciduous trees.

A beam for strapping operations is selected with a section of 0.15x0.15 m. When buying this material, it must be carefully examined - there should not be any cracks.

Before starting work, the bars must be treated with an antiseptic: this will prevent the penetration of the fungus into the tree and stop the processes of decay. They are then treated with a flame retardant to improve fire resistance and reduce the ignition rate. This must be done if the bars are made of pine, as there is a lot of combustible resin inside its wood.

In order not to make a mistake when calculating the required amount of materials, it is advisable to add another 10-15%.

If an adhesive beam is used (it is produced by gluing together several well-dried boards), then the use of a fire retardant only improves the properties of the material. Such bars have more accurate dimensions. The grooves and protrusions that they have allow you to more firmly strengthen them during construction. The moisture protection of such elements is good, it is not necessary to treat with an antiseptic, but the price of such a bar is higher. The adhesive material does not rot and weighs a little less.

Technological process of creating pile foundation piping

This work is done as follows:

1. The foundation is being prepared.
2. Material for construction is selected.
3. Structural work is in progress.

The first operation is performed in 2 stages:

1. After installing and connecting the piles, you need to make sure that the resulting foundation is horizontal. If any part is installed above the desired horizon, then it should be deepened. If it is below the required plane, then a gasket of the appropriate thickness must be added to the pile head. It is made from wood or metal.
2. Waterproofing is being done. Roofing material is laid on the ends of the columns. You can do it with bitumen. This must be done very carefully so that there are no gaps, otherwise moisture will penetrate the foundation of the house and ruin it.

The second operation begins with the drying of wooden beams. Then the corner elements of the future frame are selected, and cuts are made at their ends for connection to the lock.

After the end of the process of leveling the screw piles, laying a waterproofing coating on them and preparing the beams, they begin to produce strapping work. This is done in this way:

Figure 1. Strapping allows the house to last for many years.

1. The corners are drawn first. A point is determined, which is taken as the first external corner, it is marked with a nail. Other corners are also marked, and their straightness is corrected with a metal square.
2. One of the corners of the future structure is made, and all pre-prepared bars are laid in place. Between their joints, you can lay a tape of jute. On straight sections, the elements of the pile foundation are connected into half a tree. To connect wooden elements to each other, you can use metal corners.
3. After connecting all the bars, all angles are checked for accuracy. Then the horizontality of the resulting grillage is controlled. This is done using the building level.

Next, the process of fixing the resulting structure to the piles begins. Very often this is done with bolts. To do this, a hole must be made in advance on the head of each pile, and after laying the beams, drill wooden structural elements in the right places. All this is connected with bolts or screws.

After that, cuts are made in the grillage for logs and beams for partitions. Before this, it is necessary to lay waterproofing in open places. The resulting grillage is shown in Figure 1.

How is double tying done?

It is much more reliable than the above design and has the following advantages:

A house on stilts keeps warm longer in the cold season.

1. The house retains heat better.
2. With a double strapping, cuts are not made from the timber for the beams, so the grillage is more durable.
3. If the lag needs to be repaired, then it is easy to remove them with double strapping. They are not embedded in the base.

To make a similar design for the first crown, it is necessary to use a material with a cross section of 0.2x0.2 m. It is installed as described above. It will be necessary to make cuts for partitions from the bars. After that, proceed to install the second crown. For him, you need to purchase a material with a cross section of 0.15x0.1 m, which is installed at the end. Before that, all the joints of the first crown are overlapped, and the corners are connected into a straight cut.

The partition beam is attached to the end in the middle of a similar element in the first row so that a ledge is obtained. Lags for the floor are laid perpendicular to these beams after 0.7-0.8 m. They are attached to the protruding parts of the beams with nails. The accuracy of the geometry of the strapping work is checked by measuring the diagonals. On this, the work can be considered completed.

What difficulties may arise?

When making a grillage, some difficulties may arise that must be overcome as follows:

1. If the piles have a different level, but there is no way to deepen them, then they make a recess of the required length in the beam.
2. If the foundation turns out to be different from a square, then it can be brought closer to this shape, respectively, by changing the geometry of the grillage.

An approximate list of tools and materials for tying from a bar:

1. Screw piles.
2. The beam is wooden.
3. Ruberoid or bitumen.
4. Metal corners.
5. Screws, nails, bolts.
6. Chainsaw or hand saw.
7. Electric planer and drill.
8. Screwdriver or screwdriver.
9. Building level, metal square for checking angles.
10. Roulette and pencil.

It is possible to make a grillage with your own hands only with strict observance of all the above technological operations.

If you skip even one point, then we can assume that all the work for tying the screw piles was done in vain.

What is a pile foundation? This is a certain number of linearly arranged elements that are not connected to each other in any way. To combine the piles into a single structure necessary for the formation of the foundation - the pillars of the building, it is required to equip each with a head, on which then to mount a grillage or strapping.

Purpose of strapping

A residential building does not weigh 2 kg, which means that the foundation must be reliable, monolithic, even if they are made of separate piles. Strapping or grillage is necessary to evenly distribute the weight of the future building. Reliable coupling allows you to connect disparate piles into a single foundation body. In addition, the strapping aligns the top line of the piles into a single horizontal plane. This is extremely important for the stability of the house-building structure.

Important! The pile-screw foundation is an excellent option for residential buildings made of timber, logs, frame houses made of Sip panels. It is lightweight, environmentally friendly, cheaper, and faster to install.

In the field of low-rise construction, this type of foundation is more rational than other foundations in many respects.

Strapping is a must. A pile pipe peeping out of the ground is a shaky and unreliable element in itself, but in conjunction with all other pipes it is able to withstand heavy loads. The upper end of the pile is equipped with technological holes that are needed for mounting the layer between the foundation (piles) and the structure - this is the strapping or grillage. The strapping is also a kind of protection of the walls of the building from the ground.

You can strap with different materials, but the best for these purposes is timber. The rectangular shape facilitates installation work on the creation of a grillage and the initial stage of laying walls. The arrangement of the grillage using a beam is recognized as the most effective among all strapping methods.

Features of the procedure

The grillage can only be made of solid wood, but it is allowed to use glued beams, which are superior to natural ones in their technical characteristics. Glued laminated timber is much more stable than solid timber, made by gluing elements with multidirectional fibers under pressure, the material has increased resistance to environmental influences. The workpiece must be equipped with smooth side surfaces.

It is preferable to make a grillage from conifers. Their advantages are in the duration of operation, in that resinous wood is less susceptible to the harmful effects of moisture, biological pests, fungal foci or mold colonies rarely appear on it. Wood is a warm material, a floor insulation cake starting with a wood base is much warmer than a similar cake, but on metal. Conifers are much cheaper than others, which is also an advantage. Installation of the grillage is not difficult, all work can be done by hand, saving money on this.

Important! The beam must be even, not behaving, without cracks, chips and any other deformations. The length of the beam is equal to the pitch length of the screw piles. The fastening of the beams to each other in the strapping is carried out only above the pile support and in no other way.

Beam connections in strapping

• in half a tree, the connection occurs at a right angle, the beam from the end is chosen half;
• in the paw, the connection occurs at an acute angle, the timber is also chosen from the end.

The sections of the joined beams should fit snugly against each other, mirroring the recess. Fasten the elements using the following fasteners:

• metal plates;
• clamps;
• corner;
• staples;
• bolts, screws, anchors.

To better understand the principles of docking, look at the picture.

Advice! When calculating the strapping beam, 10-20% should be added in case of marriage, technical error. Buying more material from another batch is undesirable for a number of reasons.

In order to have no doubts about the strength of the grillage, it is worth applying the principle of double fastening, fastening the joints using several mounting technologies.

Installation of the grillage

Installation begins with the installation of heads on piles. These can be metal plates, but for timber piping, U-shaped flanges are used, placed on the “head”, that is, “P” is turned upside down.

Bar blanks are prepared in advance. At the ends, cuts are made corresponding to the connection in half a tree or in a paw. They also prepare grooves into which lags will then be installed.

Important! The flanges are covered with roofing felt so that the wood does not come into contact with the metal.

The binding starts from the corners. The first two beams are joined at an angle of 90 °, for fidelity, the angle is checked and fixed with self-tapping screws. So I equip all 4 corners. Then continue tying on the sides. The joints are additionally fastened with plates or other fasteners and laid with jute to avoid the formation of cold bridges.

It is better to do double strapping, it is considered more reliable and durable. Double strapping technology, the difference is that for the first layer a beam of 200x200mm is used, and for the second 100x150mm. The top layer is laid on the smaller side, long side up. Cuts under the logs are made in the bottom row, the joints of the timber of the first and second layers should be spaced apart from each other.

Before proceeding with the strapping, you should check the quality of the installation of the piles, each of them must be installed strictly vertically.

Fastening with anchors, self-tapping screws, tightening bolts must be carried out strictly in the center of the connection. It is advisable to use clamps, it does not lead to the formation of cracks.

It is necessary to make accurate cuts, extra cuts will weaken the structure.

Important! There is an opinion that a strapping is not needed for a house made of timber, that the lower crown plays its role, and the cuts under the logs are made in the upper crowns. The opinion is doubtful.

And lastly, if the piles are not twisted to the same level, you can twist the pile, cut off its top or deepen the end into the strapping beam. If a crack appears in the beam, it needs to be replaced.