Tying the foundation on screw piles: recommendations for tying with a channel and step-by-step instructions for tying with timber

The joints of the boards do not need to be made hanging. Join the boards at the pile heads. By splicing timber in this way, you will increase the consumption of wood, but ensure the strength of the pile frame. The beams on the pile heads also need to be spliced ​​correctly. If a solid beam is spliced, then cuts are made on two adjacent beams. The upper half of the beam is sawed on one beam, and the lower half on the other. After this, both beams are connected into a lock. This connection is called a “half-tree connection.”

At first glance, everything looks extremely simple. But there is an important rule for connecting two elements of one load-bearing beam: both adjacent beams must rest on the head of the pile at the point of connection of the load-bearing beams, and not just one. First, let's give an example of an incorrect connection.

The support area of ​​the beam on the head (at the junction of two purlins) must have a length of at least 90 mm. In the figure, the beams are “cut” at the junction. One has the upper half cut off, the other has the lower half. If the beam rests on the pile head only with the “cut” part, then its working section should be taken as the cross-section of only this part. If the beam rests completely on the head (at least 90 mm in length), then everything is correct: the harness will work like a solid beam.

The purlin in this case is the supporting beam in the framework of the frame house.

This rule also applies to corner trim joints. Here are examples of correct beam connections.

In order for the beam to have a sufficient support area, the pile heads must initially have dimensions corresponding to the cross-section of the beam.

The question naturally arises: how to lay beams at the junction of several beams (for example, if three beams are joined at once on one head)?

Beam junctions can be arranged in two ways. In the first case (when all the beams are load-bearing), in order to provide a sufficient support area, it is necessary to increase the head. In the second (when only one beam is load-bearing), we place the load-bearing beam on the head, and the auxiliary beam can be attached to a suspension - such a part (in fastener stores it is called a “beam holder”).

The increase in the support area is carried out according to the following scheme:

With the correct placement of piles, even auxiliary beams will have several points of support, which will make the foundation structure quite strong.

If you approach the design of the harness more rationally, if, where possible, you use beams of small width, then there should be no problems with constructing the correct connections.

Stacked load-bearing beams (beams made of boards) at the junction points must also have a sufficient support area. We present to your attention examples of correct connections of inlaid timber in various sections of the strapping.

The listed recommendations should be followed, if only so that after assembling the wooden frame you do not find the following picture at the base of the house.

Strapping options

Tying piles with timber

Foundation tied with timber.

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

The pile head is mounted after leveling (cutting) the pile and after pouring concrete 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 the piles.
3. Waterproof the material.
4. On the beam, which falls on the joints of the corners of the house, grooves of the required size are cut out for subsequent connection of the wooden parts with each other.
5. The timber is laid on the pile caps along the perimeter along the entire contour of the foundation so that the joints of the separate parts of the grillage are fastened together on the caps. The joints are laid with a rope for better compaction.
6. Level the grillage and carefully check the angle: it should not deviate from 90 degrees.
7. The timber is fixed to the pile heads using self-tapping screws.

Tying piles with boards

When installing a pile foundation, planking has a number of undeniable advantages compared to timber:

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

Tying screw piles using boards is performed according to the following algorithm:

1. Between the pile heads and the piping itself, a waterproofing, moisture-proof layer must be made, often from high-quality roofing material.
2. Then a log of approximately 50x150 cm in size is mounted on the timber frame, which is secured to the heads using reliable bolts.
3. Trim boards are placed on the bench in three layers: first one board along the entire perimeter of the base, then the second and third. All layers must be carefully fastened with nails.
4. If the height of the trim exceeds 40 cm, it should be further strengthened using corrugated pipe.

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

Metal grillages make it possible to use a pile-screw foundation when constructing not only wooden buildings, but also one-story buildings made of cinder blocks, foam concrete and gas silicate.

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

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

In this photo, the foundation is tied with both a channel and a profile pipe (bottom).

Tying a pile foundation with corrugated pipe is done in almost the same way, however, the resistance of such material to significant mechanical loads may be much less. Among the advantages of the pipe, we note its low cost and low weight.

Tying piles using a reinforced concrete grillage

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

Piling of piles using a reinforced concrete grillage: final version.

When tying piles using a reinforced concrete grillage, you must proceed as follows:

1. The pillars of the piles are set to the same level.
2. Formwork is made from planed boards for further pouring with concrete, which is lined with oilcloth on the inside to prevent leaks.
3. A double-circuit frame is created using metal reinforcement. Horizontal reinforcement elements are fastened vertically with jumpers made of knitting wire.
4. The reinforced frame is placed in the formwork in such a way that at least 5-6 cm separates the metal from its surface.
5. The metal frame is welded to the piles and the formwork is filled with concrete.

Features of the procedure

The reliability of the entire structure depends on how correctly the strapping is performed.
Therefore, to create such a foundation, it is necessary to perform a lower harness that connects the foundation, walls and floor joists. Also, without it, it will not be possible to create a level platform, which is important when creating the correct load

Therefore, during the installation process you must adhere to the following recommendations:

• first lay a waterproofing material on the foundation elements (this can be roofing felt or more expensive and durable analogues);
• make sure that the board is well calibrated, all its sides are smooth (all strapping elements must be carefully selected in size);
• treat the strapping material with an antiseptic composition;
• make sure that the strapping is performed in a strictly horizontal plane (this will eliminate uneven loads).

When is it used?

The harness is a connecting structure, without which the area of ​​support on the soil will be significantly lower. The use of wood or metal as a lining material allows you to protect the underground from any influence from the street.

The strapping is necessary to distribute the load. You cannot do without it if, due to difficult soil, the supports are not buried evenly.

If you do not create a single structure, then in a few years distortions may appear and the building will shrink. This can also happen if there is a harness, but the chances of problems occurring are significantly reduced.

However, boards are used as strapping for the lightest buildings, most often for frame ones.

Advantages and disadvantages

Tying a screw foundation with a board has a number of advantages when compared with similar tying using timber:

1. The board is much less deformed and does not crack. Due to the massive cross-section of the timber, cracks often appear on it already at the stage of installation of the structure.
2. It is much easier to connect the boards in one line. Sometimes during the construction process it is necessary to make beams longer than 6 meters. When using timber, such an element cannot be lifted.
3. Working with a board is much more convenient, since it is lighter. This allows you to “try on” the structure and adjust its position.
4. The boards do not need to be pre-dried.
5. If you compare a board and timber of the same thickness, then the board can withstand more weight.

Among the disadvantages of tying with a board, one can highlight the fragility of the material. Although a lot depends on the specific type of wood. But even under this condition, some people prefer channels (tied with metal materials).

Pile tying:

main methods and features of their application

If a pile foundation is chosen as the foundation for a future building, then many questions immediately arise: which piles to choose, how to tie the piles correctly, what to tie the piles with? In this article I will try to answer these questions.

So, in order. If you have a house made of logs or timber, and the piles are on a flat area, then piles with caps may be quite sufficient. In this case, the lower crowns of the future house will serve as the binding. But what to do if the house is frame, or made of vulture panels, or a house made of timber or logs, but with frame partitions? In this case, it is necessary to tie the piles with a material that will prevent the piles from “walking” during lateral heaving of the soil, and will not allow the walls to sag on spans greater than the installation width of the racks.

There are quite a lot of strapping options, but we will focus on the main ones: I-beam, channel, timber, concrete (Fig. 1). In this case, screw piles, bored piles, concrete pillars, etc. can be used as piles.

If you choose bored piles as a support (Fig. 2), during pouring it will be possible to release a pin with a diameter of 14-16 mm or reinforcement from the pile. Since such piles have a diameter of 200 mm or more, they usually do not require caps and it is possible to lay timber frames or make a grillage directly on top of the piles.

If screw piles are chosen as piles, then pile heads will be needed for tying with wood. They can be round, oval, square, rectangular, with or without reinforcement, with support or with additional support. But usually square ones are used, measuring 20x20cm, this is the optimal size, it has a sufficiently large support area both for corners and for intersections and joints, it is not large and not small (Fig. 3-5).

When using a metal channel, I-beam, etc. as a strapping, it is welded directly to the concrete-filled pile. Also, usually when choosing a metal, the piles are tied with a channel 16 cm wide (see picture below), less often with an I-beam, due to its higher price and the inconvenience of installation at the joints, since you have to cut quite a lot of shapes and then weld them. In terms of load-bearing capacity, an I-beam is of course more advantageous, but with a light house and a pile spacing of less than 3 m, a 16 cm channel may be sufficient. I always recommend a channel to customers, and I explain, as I wrote above, that the channel will not allow the piles to “walk” during frost heaving of the soil, and an additional beam laid on top, at least 15x15 cm, will reduce the deflection by about 2-4 times, depending on the length of the span and its load.

If you have chosen a beam as a strapping, then there are several options for strapping: a beam in one row, a beam in 2 rows with a shift and overlapping cuts, or a composite beam. As a composite beam, boards are used, installed on an edge and knocked together in a checkerboard pattern (see pictures below). The advantage of this method is that we connect the strapping fairly evenly and distribute the load evenly across the pile and its entire head. The disadvantage of this technology is that it takes quite a long time to mark and adjust everything, and then a lot of knocking together and tying together, in most cases with bolts or studs. With this method, it is advisable to use well-treated dry boards so that mold and mildew do not get between them during the construction stage.

When choosing timber as a piping (see pictures below), you need to make the correct cut. The rule says: the most loaded beam is sawed from above, and the less loaded beam is sawed from below (Fig. 5 - dark beam is loaded, light beam is less loaded). When using a strapping of two beams, the cuts are repeated exactly the opposite and the joints along the length are shifted to the adjacent pile. Also, recently, with the appearance of good fasteners, very often they began to use cuts in 1/2 or 3/4 of the tree, not in height as always, but in thickness (Fig. 4) or a version of the cut at an angle (Fig. 6). In these options, you need to use studs and/or long and strong screws. The method is again complicated due to the need for high precision cuts and joining of wood both with each other and with the pile heads.

To screw the timber to the heads, studs with a diameter of 8-12mm or plumbing bolts with a diameter of 10-12mm and a length of 100-150mm are usually used. The inconvenience of working with studs is that you have to drill holes in the timber for them, using a 20cm long drill, from below, through the head. But if you add a 20cm+30cm drill and only 30-40cm clearance between the pile head and the ground, then this becomes a big problem. For the bolts, a drill with a diameter of 6 mm and a length of 10 cm, with drilling at a slight angle, is sufficient.

What you need to know about screw piles

Piles are not only steel screw, but also concrete. In some cases, especially during the construction of large and heavy structures, preference is given to the latter, as they are more reliable and durable. But before you make a pile foundation with your own hands from concrete, you should carry out geological surveys and engineering calculations to ensure that the decision made is correct.

However, such costly measures are usually carried out when building a house made of bricks, concrete blocks and other massive materials. Lighter wooden, panel and frame buildings can be placed on a base of screw piles on any soil except rocky.

But if we are talking about a permanent structure, calculating the parameters of the piles is still necessary. It can be neglected only when constructing secondary structures - gazebos, sheds, bathhouses, fences. And only for such structures can you use homemade screw supports.

Metal fence on screw pilesSource spravka-region.ru

Pile components

Externally, the screw pile resembles a garden drill and consists of the following parts:

• steel pipe barrel;
• sharp cone-shaped tip;
• blade (screw);
• head.

The main difference from the drill is the perpendicular position of the blade relative to the trunk, which allows it to enter the soil without loosening it or disturbing its density.

The second difference is the cap in the upper part of the structure, intended for tying all installed elements and grillage installation, since it is impossible to make a pile foundation without such support platforms.

In factory conditions, piles are made either by casting or welding using professional equipment. They can be of different lengths, differ in blade diameter, trunk diameter and thickness. These parameters are selected depending on the calculated load on the foundation and the depth of dense soil layers.

In addition, during production, all products are coated with a layer of anti-corrosion coating, which prevents the destruction of metal that is in constant contact with a humid environment.

Factory-made pileSource www.balticdom.ru

Differences between handicraft and factory designs

The production of foundation piles is regulated by regulatory documents. In particular, GOST 8732 determines the quality of the metal for the barrel, and GOST 9.307-89 determines the quality of the zinc coating. They specify the grade and thickness of steel, its chemical composition and other characteristics. When deciding how to make screw piles with your own hands, it is advisable to study these documents in order to obtain high-quality products.

Not having the opportunity to manufacture them themselves, but wanting to save on supports, some developers buy them from “handicraftsmen” - craftsmen who produce metal structures in conditions far from factory ones. Of course, they do not give any guarantees, and it is impossible to verify the quality of such products before construction begins.

In particular, both homemade and handicraft products may not have the necessary strength, the blades may be deformed or torn off when screwed into dense soil, and the lack of high-quality anti-corrosion treatment can lead to destruction of the metal and weakening of the foundation.

The destruction of just one support will lead to weakening and distortion of the foundation. Source tverstroy.rf

However, the question of how to make screw piles yourself remains relevant for many due to the high cost of certified products. Experts allow the use of homemade supports, but only when erecting lightweight buildings, the reliability and durability of which are not of decisive importance. The foundation for residential buildings, permanent outbuildings, brick and stone fences must be built from factory piles produced in accordance with regulatory requirements.

Step-by-step installation instructions

Let's consider the procedure for installing a pile-screw foundation for a bathhouse. We’ll skip the design and calculation process and go straight to practical actions.

The work is carried out in stages, the following operations are performed:

Preparation

The area is cleared of unnecessary objects, plants and other obstacles. It is necessary to provide access routes for equipment if mechanical installation of piles is planned. Purchase and delivery to the site of the required number of trunks of the required size.

You will need the following materials and tools:

• Shovel.
• Roulette.
• Scrap metal and two pieces of pipe, 1.5-2 m each, into which this scrap fits freely, but without unnecessary play.
• Grinder with cutting wheel.
• Welding machine with electrodes.
• Heads for the pile size used.
• Cement and sand for making concrete.
• Pegs for marking.
• Laser level.
• Coating for metal parts, protection of welds.
• Channel, I-beam, strapping rail.

Marking

Using pegs, the installation locations of the piles are marked according to the design data. You should start marking from the corners, immediately checking the equality of the diagonals. Until they are aligned, marking cannot continue.

The installation points of the piles are marked with pegs. After marking the corners, they move on to the intermediate piles and mark their position. Then, using a shovel and personal courage, small depressions up to 30 cm deep and a width equal to the diameter of the blades are dug at these points.

This will allow the piles to enter the ground more easily and provide less deviation from the vertical.

Dive

Screwing of piles is carried out according to a certain pattern. This is done so that already installed trunks do not become an obstacle to other supports.

This is especially important when installing by machine, where the equipment must come close to the immersion point

Usually they start from the center and move sequentially to the edges in a spiral or snake.

When driving piles, it is necessary to constantly monitor the vertical

It is especially important to do this at the initial stage, when the barrel swings quite freely and can be installed at an angle

It is forbidden to twist the pile back for leveling; it is prohibited to install it at this point a second time due to the violation of the strength of the soil after contact with the blades. All corrections are made at first, when the barrel is immersed to a shallow depth.

Trimming, tying, pouring concrete

After installation of all piles, trimming is carried out. A laser level is installed to mark the horizontal plane at the required height, and cutting lines are marked on the surface of the piles with chalk or a white marker.

Use a grinder with a cutting wheel to cut off excess pieces of pipe.

After this, the strapping is performed. All piles are connected to each other in the longitudinal and transverse directions by welding. Pieces of channel, I-beam or other type of rolled metal cut to size are used.

After connecting the piles into a single system, you should immediately paint all welding areas with a protective layer of paint, kuzbasslak or other material.

Then the internal cavity of the piles is filled with concrete. This gives the trunks additional rigidity and resistance to lateral heaving loads. It is necessary to use thick stamps, starting from M200 and above.

Heads are installed and fixed onto the filled piles, forming platforms for installing a grillage and intermediate (internal) supports.

Grillage

For a bathhouse, a wooden beam with a cross section of 150: 200 or 200: 200 mm is usually used. The beams are laid on the head platforms, having previously placed a double layer of roofing felt on the metal. The corners are connected halfway through the tree.

They carefully check the equality of the diagonals, align the beams along their axes, and then fasten them to the heads using specially created mounting holes. Wooden beams should be immediately covered with waterproofing material to protect them from moisture.

Method of bundling with a profiled pipe

A profiled pipe has a structure similar to a channel, but in terms of strength it is much inferior to it.

This is due to the less durable metal used to make the profile pipe, thinner walls and other features of the material . To achieve maximum strength, corner joints are made overlapping or overlaying.

As an option, the ends are trimmed at 45°, welded, followed by strengthening the joint with an oblique angle for bolted joints.

Procedure:

• Trimming piles, installing caps.
• Laying beams along the outer perimeter, connecting corners.
• Laying internal beams, welding with external elements.
• Tying the remaining supports to obtain maximum rigidity.
• Applying a layer of protective anti-corrosion coating.

IMPORTANT!

If possible, all connections are reinforced with metal gussets installed on bolted connections.

Types of strapping

The piping belt for a pile foundation can be implemented in different design options. They have their own capabilities and are designed to work with different loads and conditions.

The following types exist:

Wooden

A beam with a cross-section of 200:200 mm is used, or a pack of edged boards 50:200. The beams are installed around the perimeter of the house (under the external load-bearing walls), along the lines of the internal load-bearing walls, and also connect the remaining supports in order to equalize the loads and tie all the trunks to the common system .

Corner joints are made into the wood floor, fastening to the ends is done through a double layer of roofing material for waterproofing.

The advantages of this solution are:

• Ease of processing, availability of material.
• The wood has sufficient strength and relatively low weight, which does not load the foundation.
• Installation is possible in the field, without the use of construction equipment or even without power tools.

The disadvantages of wooden types of strapping can be considered:

• Features of wood, tendency to warp or crack, need for high-quality waterproofing, etc.
• Fire hazard of wood.
• Possibility of material damage by insects or rodents.

Despite the obvious disadvantages of wood, a timber grillage is a common and popular option.

Metal grillage

Metal binding requires the use of welding.

From an installation point of view, it has noticeable advantages:

• High connection speed.
• Durability, resistance to all possible loads.
• A wide selection of types of rolled metal, allowing you to obtain various strapping options.

Along with the advantages, metal strapping has disadvantages:

• The metal's tendency to corrode.
• The need for periodic maintenance of the structure (painting with waterproof polymer materials).
• Welded joints require the participation of a professional welder who is able to correctly select the operating mode and amperage. Otherwise, the seams will be brittle and brittle, which will create a significant danger to the building.

The main argument in favor of creating a metal frame is the high maintainability and speed of assembly of the grillage.

The cost of rolled metal and welding work is noticeably higher than that of wooden beams.

However, there are about the same number of supporters of this type of binding as there are fans of wooden parts.

The strength and stability of the metal are highly valued by users and increase the competitiveness of the material.

IMPORTANT!

To increase the strength of the metal frame, it is recommended to use additional bolted connections.

Concrete

Concrete lining is almost a full-fledged analogue of a pile-strip foundation.

The fundamental difference is the distribution of loads - on pile-strip foundations, both elements share the loads equally, and the concrete grillage of a pile foundation only transfers the load to the supports, without performing load-bearing functions as such.

At the same time, being only an intermediate element, concrete piping allows you to get the maximum effect.

It has high strength, durability, and resistance to stress.

In addition, the concrete grillage is able to compensate for changes in loads or load-bearing capacities of individual supports, redistributing or partially assuming new working conditions.

The advantages of this design are:

• Ensuring maximum load-bearing capacity of the system.
• Independence from climatic or weather conditions.
• Relatively low need for periodic maintenance.
• Durability, reliability of the material.

The disadvantages of concrete elements are:

• The complexity of creation, the need to perform various successive stages of work.
• Large volumes of materials (concrete, reinforcement, wood for formwork, waterproofing materials, etc.).
• It takes a long period of time for the lining to harden (28 days from the moment of pouring), during which further construction is impossible.

The construction of concrete piping is usually chosen during the construction of large and massive buildings, where it is especially important to ensure the strength and reliability of the belt despite the high consumption of materials and labor costs

NOTE!

For some types of piles, a combined version of the piping is often used, in which the grillage itself performs the main load-bearing functions, and the shafts are additionally connected by metal jumpers. This type of dressing is used, in particular, for screw piles. It strengthens the system and reduces the possibility of loosening or loss of traction.

Grillage calculation

Calculating a grillage is a responsible and extremely complex engineering task. All that an untrained person can do on their own is to calculate the amount of materials needed to create a particular structure.

For a full calculation, you need to contact a specialized organization. At a minimum, you can use an online calculator (preferably several) to get certain data.

To independently calculate the amount of materials, you need to determine the total length of the grillage. If you are planning a wooden or metal belt, this length will be the required amount of material. With concrete structures it is somewhat more complicated:

Calculation example: let’s say there is a 6:8 house with two internal load-bearing walls of 6 and 4 m.

Then the total length of the grillage:

(6 +

Then we calculate the volume. To do this, you need to calculate the cross-sectional area.

If the tape is 40 cm high and 30 cm long, the cross-sectional area will be:

0.4 · 0.3 = 0.12 m2.

Volume of concrete required for casting:

0.12 · 38 = 4.56 m3.

NOTE!

When performing calculations, you must use the same units of measurement, otherwise the resulting values ​​will be incorrect.

Basement siding

The easiest and cheapest way to cover a building on screw piles is with this material. Cladding has the following advantages:

• low cost (even taking into account components);
• ease of installation with your own hands;
• durability;
• wear resistance;
• resistance to rotting and mold;
• wide range of colors;
• ease of operation.

Basement siding
But along with its advantages, siding also has a number of disadvantages. For example, it will not be suitable if it is necessary to insulate the basement of a house on screw piles.

Installation technology

It is quite simple to do house cladding; you just need to know the order of work and the nuances of their implementation. The construction of the plinth is carried out in the following order:

1. Installation of sheathing under siding. First of all, fix the bottom bar. It is located parallel to the ground. The distance from the soil surface is set to 150-200 mm. This gap is necessary to raise the skin above the ground. The distance from the panels to the ground after installation should be 50-70 mm. This layer compensates for soil heaving in winter. In warm regions or on coarse foundations, the gap can be made smaller.
2. Wooden boards are attached to the piles. To do this, special brackets must be welded to the heads in advance. You can also use a metal profile as a frame, which is welded to the foundations without additional elements.
3. Similarly to the first, a plank is attached to the upper part of the base of the house on a screw foundation.
4. A vertical sheathing is sometimes made between the longitudinal guides. The need for it depends on the height of the base. When the building is raised high from the ground, it is worthwhile to provide additional elements as reinforcement.
5. Siding begins to be installed from the bottom starting strip. Base panels are installed on it. The elements are fastened to the sheathing using self-tapping screws. To install corners, special profiles will be required.
6. To remove precipitation from the basement part, flashings are installed on the siding.
7. The finishing of the lower part of the house is completed after completing the gap between the ground. The space must be closed so that air can enter, but small debris, insects and other living creatures do not have access.

All wooden elements are treated with antiseptic compounds before starting work. This is necessary to prevent damage by fungus, mold and rot. As an additional measure, fire-fighting treatment with fire retardants can be performed.

Siding is the most common option. In this case, finishing the building is easy and quick. The installation should begin after the construction of the house is completed, when all communications have already been completed. To prevent pipes from freezing in a ventilated underground, they are wrapped in heat-insulating material. Most often, mineral wool is used for these purposes. You can use ready-made thermal insulation elements for pipes, or you can make insulation using mineral wool mats (wrapped in rolls).

Pay attention to the soft waterproofing of the blind area

Siding will be an excellent option to cover the space under the house. To attach the panels to the sheathing, you need to prepare self-tapping screws.

Channel bandage method

The difference between the channel piping technology and the method of installing a profiled pipe is the absence of standard ends.

The channel is installed with the wide side up, forming a horizontal platform along all the beams.

Otherwise, the procedure is similar to the technique for installing a profile pipe.

The usual channel sizes are m for piles with a diameter of up to 108 mm (a 160 mm channel is used for them).

Welded joints are additionally secured with bolted joints using gussets.

Welding must be carried out by a professional qualified specialist who has permission to work with critical structures . Waterproofing of the trim is carried out using traditional coating materials or protective polymer coatings.

Recommendations from experts

Before starting work, you need to look at all areas and make sure that the columns are the same height. The success of the entire construction depends on this. The height of the piles must be perfectly accurate, otherwise it will be impossible to do further work well. If any pillar is higher or lower, it should be leveled. Otherwise, in the future there may be a strong distortion of the floor in the house. The strapping connection must be made exactly in the center of the area. It is in this place that the screws are fixed. Installation of fastening elements makes the entire structure as strong as possible, so this issue should be treated with great attention

Fixing the screw in the center of the beam will prevent the wood from cracking. Before installing the beam, it is important to check that the length of the elements is correct. A wooden block that will be mounted horizontally must be twice as wide as the pile. Only then will the entire structure be especially strong and reliable. It is better not to experiment with new technological methods during the construction of a structure.

Properly performed work will provide the necessary technical parameters to the entire foundation of the house. If the master does not have confidence in his own abilities, it is better to call specialists to perform a high-quality grillage. Compliance with all rules and recommendations of specialists will ensure high strength of the structure. In order not to redo the grillage in the future, the beam must be accurately aligned horizontally. Use impregnation compounds that will protect the material from moisture. Tying a pile foundation requires a complete understanding of all stages of the process. Firmly fixed structural elements will allow you to correctly distribute further load on the building, save the house from destruction and extend its service life.

What is it and why is it needed?

Roughly speaking, the frame is the foundation of the subfloor of the future house.

It is needed for:

• combining disparate pillars (or piles) into one monolithic structure;
• use as a base for installing walls and floors;
• uniform distribution of load on the foundation.

By the way, if there are differences in height at the construction site, this construction technology is definitely cheaper than a trivial strip foundation.

Installation requirements

In order for the harness to fulfill its role 100%, a number of requirements must be met during installation:

1. the strapping material and posts must be securely fastened with bolts, staples or plugs;
2. laying must be carried out strictly according to the level (if you need to add, the height is reached with plates, if removed, it is cut down);
3. between the piles and the strapping material (if it is a solid or composite beam) there must be a layer of waterproofing;
4. each corner must be reinforced with corners, staples, nails, etc.

Material requirements

When selecting a material, meaning the choice between wood, metal and reinforced concrete, the following factors must be taken into account:

• the width of the strapping material should be twice the diameter of the piles;
• it must be durable and not subject to deformation;
• the cross-section must be the same around the entire perimeter;
• ideal evenness must be maintained along the entire length;
• it should be easy to process.

Recommendations from the experts

When choosing a frame made of wooden beams, you should adhere to the following procedure:

• upon completion of installation of screw piles and leveling, metal platforms made of sheet steel 20x20 cm and at least 4 mm thick should be welded onto their heads;
• in these fragments of metal sheets it is necessary to drill four holes with a diameter of 8 mm to secure the beam;
• upon completion of work, welding seams and caps must be treated with an anti-corrosion compound;
• It is necessary to lay waterproofing on top, usually from roofing felt in two or three layers, which will prevent the accumulation of moisture at the junction of metal and wood;
• one row of timber or a package of boards is laid on previously prepared sites;

It is important to lay the joints of the timber at the end in a “dovetail” or “foot-to-foot” manner; when all the parameters have been checked, the bars can be fastened to the supports with screws, which should have a diameter of 8 mm and a length of 150 mm, they should be screwed in with a wrench; First you need to make a hole with a diameter of 6 mm in the timber with a drill, three-quarters of the length of the screw. This is necessary so that the timber does not crack; The structure is even more securely secured with bolts with a diameter of 8 mm, which should pass through the beam from top to bottom

To do this, you first need to make a hole using a drill 10 mm deep. This is necessary for attaching the bolt head and washer; the diameter must be at least 30 mm.

The harness is also called a grillage. Today, a grillage is one of the best options, characterized by very high quality and maximum reliability when strengthening a pile foundation. You can create a reliable support for your home with your own hands. Before starting work, you need to prepare a level and roofing material, as well as self-tapping screws. Don't forget about the hammer and metal corners. The choice of other materials and tools depends on the specific technology. The best technology, according to experts, is using clamps and threaded connections.

About tying screw piles, types of tying, purpose, necessity, see the following video.

Timber or board - which is better?

Let's talk about what material is best to use to create a wooden frame. Construction regulations allow the use of solid wooden beams (150x150, 150x200, 200x200) or timber sewn from several boards (50x200). Laminated timber qualitatively replaces solid timber and even surpasses it in some characteristics. Three boards sewn together replace a beam with a section of 150x200, while four boards are similar to a beam of 200x200.

The beam, one side of which is 200 mm, is laid on the heads with the smaller side. The height of the strapping is equal to 200 mm.

Both options (both with timber and with boards) are popular and both are correct. At the same time, having studied the advantages and disadvantages of each material, many developers make their choice in favor of stitched boards.

AlexSpb User FORUMHOUSE

Why do you need to use 150*200 timber? Knock down 3 50*200 boards instead and don’t bother with this log. This topic constantly comes up on the forum.

The word “log” was not mentioned by the user by chance. Solid timber is a relatively heavy building material and, with a limited number of workers, moving it from place to place (even on a small construction site) will be very difficult. In addition, solid timber does not resist bending well (worse, in any case, than boards placed on edge), which makes its use less practical.

Boards, unlike timber, must be firmly connected to each other before installation on piles. And these are additional costs, and this, perhaps, is their main drawback.

builder FORUMHOUSE user

The boards are nailed together with nails in two rows with a pitch of 20 cm. At each head they are fastened not with one wood grouse, but with four.

As for the length of the nails: for a composite beam of three boards (50x200), nails with a length of 90 - 120 mm are sufficient. They are made on both sides in a checkerboard pattern, as user builder indicated. The distance between the nails is 20...45 cm. If the beam is made up of four boards, first 3 boards are knocked together, then the fourth is attached to them (with the same nails).

Now let's talk about the "grouse" mentioned in the quote. “Capercaillie” is a fastening element - a self-tapping screw, the head of which is made in the form of a hexagon (for a wrench or impact driver).

With the help of a capercaillie, the beam is attached to the head of the pile (the capercaillie is screwed in from below).

The diameter of the capercaillie for attaching the strapping beam is 8...10 mm, its length is 100...150 mm.

To prevent the beams or composite beams from splitting while screwing the wood grouse, a hole must be pre-drilled in the wood.

A small table will help you determine the diameter of the drill.

Attaching the top harness

Fastening can be done using three methods:

• To the end of the rack, which is located in a vertical position, with nails or screws. The method is suitable when making a structure from a single board.
• To the end of the rack through notches. With this option, a notch is made in the harness, the depth of which should be one third or half the thickness of the wood. The top edge of the rack fits into this recess.
• Fastening with steel corners. A very reliable method that strengthens the fastening using the first method.

Additional fastening with steel corners increases the strength of the structure. Source initechno.ru
The advantage of the first and second methods is that you can position and secure the vertical posts one after another. To fix it using a notch, mandatory calculations and absolutely accurate markings are required. If there are violations, then there will be a defect in the vertical placement of the racks, as a result of which the structure will begin to collapse.

Grooves are made in the strapping beam or board for all the posts, which must coincide with the same grooves that are on the fastenings for the posts of the lower trim. In addition, the structure is secured with nails. Fastenings using corners are secured with self-tapping screws.

Turnkey price

The price per harness varies based on several factors. Among them:

• wood - an example would be larch, which is more expensive;
• availability of additional work;
• region.

According to the standards, the cost is calculated based on linear footage. Average prices in major cities:

Additionally, take into account that a number of companies can provide discounts when applying. An example would be a large volume of work or similar situations.

Bottom frame of piles, strengthening the overall structure of the foundation.

The lower harness is used in the following cases:

• If the foundation is installed in an area with complex, rugged terrain, and the supports will differ significantly in the height of the part protruding above the ground level.
• If the pile foundation according to the project should have a sufficiently high height. That is, for some reason, the structure is planned to be raised above the ground surface by 1000 millimeters or more.
• In the case when a clearly massive structure is being built.
• If the house is being built on unreliable weak soil, in which horizontal movements are not excluded.

In any case, the design of the lower trim must be provided for in the project. It is compiled after calculations have been carried out and the characteristics of the soil on the site have been studied by specialists.

The top frame of screw piles or columnar foundations made of other materials is called a grillage. This is a kind of frame that connects all the foundation piles and evenly distributes the vertical load on them from the erected structure.

Many land owners, when starting to build a house, ask the specialists working on the project the question of whether there is any need to install a grillage on a pile foundation. After all, if you plan to build a frame or cobblestone house, the lower crown beam of the wall can also serve as a frame.

Using reinforced concrete

The creation of reinforced concrete piping is carried out in stages.

Procedure:

• Formwork assembly. Horizontal panels (bottom) are laid on the surface of the heads, the side walls are attached to them and are firmly connected at the top by crossbars . The internal dimensions must correspond to the parameters of the grillage.
• Laying waterproofing. The bottom and inner walls of the formwork are tightly covered with a film or layer of roofing felt. The joints of the material are overlapped by 10 cm and the joint is sealed with tape . The canvas must completely cover the entire surface of the bottom and walls of the formwork and fit tightly to the surface, keeping pace with it.
• Assembly of the reinforcing belt. Reinforcement with a diameter of 10 mm and smooth rods of 6 mm for vertical elements are used. The arm belt is knitted using soft wire, after which it is installed inside the formwork in the desired position . It is necessary to ensure that the horizontal rods are buried 2-5 cm inside the concrete.
• Pouring concrete. It is performed in one step, without long breaks (more than a day). Concrete should be poured from several points so as not to wait for the material to spread throughout the formwork . After pouring, the surface is covered with polyethylene or burlap and left for 28 days to gain structural strength.
• The formwork is removed 10 days after pouring.
• After the end of the exposure time, waterproof the surface and proceed to further work..

NOTE!

To pour concrete lining, it is necessary to use dense grades of concrete from M200 and higher.

The house hangs in the air

The foundation is finally installed, the internal cavities of the pipes are filled with concrete, and the piping of the frame house is awaiting its turn. It is quite possible to attach the strapping bars to the heads aligned at the level. But this foundation has a peculiarity: each of the piles lives its own life. Over time, it is advisable to tighten some of them. But this is backbreaking work. (See previous photo.)

The piles tied together with a grillage will redistribute the load evenly. The rigidity of the structure is enhanced by struts that relieve stress from supports above 40 cm. A rise above 70 cm requires tying with a profile pipe. The channel is preferable from rolled metal. I-beam is less desirable. And fastening the beams around the house is easier and more convenient.

Serious approach

A “heads-up” approach to foundations on screw piles is unacceptable. When ordering a project, ask to link it to a specific site with calculations made based on the type, diameter, and depth of screw supports. The weight of a small winter house exceeds 10 tons. But the bearing capacity of piles and weak soils is not unlimited. Advertising is not always honest. Piles made of steel pipe with a diameter of 57 with a wall of 4 mm will only support a summer gazebo.

A pipe with a diameter of 108–325, a wall and a propeller blade with a minimum thickness of 8–12 mm of industrial production will provide the necessary stability for the house being built. Without familiarizing yourself with the results of hydrogeological surveys in the construction area, you will not know whether it is enough to drill only to the freezing depth, what area of ​​blades to choose is determined by the bearing capacity of the soil and its resistance.

When installing a pile field, errors in pile placement are possible. It will be necessary to re-drill with an increase in depth by 1–1.2 m. The soil is loosened, it will not be able to hold the mass of the building at a given depth - it will “go on a spree”, so increasing the depth is necessary. If you do not correct the error, over time it will be pushed off the axis. Then consider that this pile did not exist at all.

Construction of a simple foundation and construction technology for a private house

It is recommended to entrust geodetic inspection and calculations to professionals. The foundation can be made independently in strict accordance with the project.

Design and calculation

Self-construction of the foundation begins with design and calculation:

• determine the type of soil;
• determining the location of the aquifer;
• calculate the area of ​​the base;
• calculate the loads from the building;
• calculate the depth, width and height of the tape.

The minimum depth of the tape for heavy buildings is calculated by the formula:

Usually developers play it safe and increase this value by another 30 cm. The cost of materials can be calculated here.

Installation in stages

Before starting work, you should stock up on the necessary materials for the current production stages. You can order ready-made concrete mortar or make it yourself, in which case you need to stock up on crushed stone, sand and cement.

To calculate the choice of concrete grade, the easiest way is to use a calculator.

The construction of the foundation is carried out in the following order:

• After clearing the area, markings are made and a trench is dug. The area is marked using pegs, tape measure and twine.

  One of the pegs should correspond to the outer surface of the foundation strip, the second - to the inner one. When constructing a shallow foundation, you can get by with a shovel.

  For buried areas, it is advisable to use an excavator with further manual alignment of the corners.

• The bottom of the trench is leveled with sand and fine gravel. Compact thoroughly, spilling with water. In regions with frosty winters, insulation material is installed to prevent heaving. Horizontal waterproofing is laid on top of the pillow.
• The formwork is being exposed. If the soil is very dense, the walls of the trench can act as formwork. All that remains is to build it up from above. When the soil is loose, the trench is dug with a reserve so that the formwork can be placed.
• At the same time, pipes for communications are installed.
• Reinforcement is performed using steel rods with a diameter of 14–16 mm and dressing wire. The iron must subsequently be completely covered with concrete.
• The concrete solution is poured over the entire surface at once. Concrete usually takes about four weeks to fully cure.

The formwork is removed when the moisture level of the concrete becomes no more than 4%, and waterproofing and insulation can begin. After filling the foundation, insulation is carried out and a blind area is made.

What does ground flooring mean?

Floors on the ground are a monolithic concrete base or screed. This design accumulates heat, making it suitable as an element of an energy-efficient home.

There are the following types of ground floors:

1. A floor slab, rigidly connected to the tape, is poured onto the carefully compacted soil.
2. A floor slab is poured onto the prepared base, not connected to the strip foundation - a “floating” screed.

Monolithic slab

To reduce the load on the tape and strengthen the areas of greatest pressure, the tape is combined with a slab base. The formwork is installed, an armored belt is made and concrete is poured.

It is kept until it hardens for 28 days. The edges of the monolith rest on the tape. This foundation combines the advantages of two types of foundation.

What kind of floor slabs should there be?

Finished reinforced concrete slabs are mounted on a belt using lifting equipment according to a pre-developed layout plan, taking into account the configuration and size of the spans.

Reinforced concrete slabs are installed on a cement-sand mortar up to 30 mm thick. The slabs are anchored to each other and to the foundation using iron rods with a cross-section of 10 mm.

Features of installation on a slope

A strip foundation is the most preferable option when it is necessary to build a house on a slope, if there is no danger of soil runoff and seasonal increases in hydrogeological activity.

The tape is well adapted to receiving and redistributing loads arising from movement or heaving of the soil. Difficulties may arise due to the inability of construction equipment to approach. An important and difficult point is to ensure that the bottom of the trench is perfectly horizontal. All other steps are performed in the traditional way.

On a slope, it is recommended to use a recessed type of monolithic structure: the greater the angle of inclination, the greater the depth of immersion.

An article about all the nuances of constructing a strip foundation on a slope is here.

Strip foundation and soils: why is it so important

When choosing the type of foundation, it is important to know exactly two characteristics of the underlying soil: their bearing capacity and heaving. Bearing capacity is highest in rocky soils; they are followed by cartilaginous ones - a mixture of sand and clay with small stones and crushed stone

Sandy soils are prone to subsidence; the properties of sandy-clayey soils (sandy loam and loam) depend on the ratio of clay and sand. The lowest bearing capacity is for soils of organic origin: peat, sapropel, silt

Bearing capacity is highest in rocky soils; they are followed by cartilaginous ones - a mixture of sand and clay with small stones and crushed stone. Sandy soils are prone to subsidence; the properties of sandy-clayey soils (sandy loam and loam) depend on the ratio of clay and sand. The lowest bearing capacity is found in soils of organic origin: peat, sapropel, silt.

Building codes prohibit resting the foundation directly on organic soils with weak bearing capacity.

Soils that are water-saturated and have a variable layer structure are also considered complex. The problem of weak soils is typical, for example, for areas located on the site of drained swamps. Building a house on a shallow strip foundation on such soils is theoretically possible, but requires quite expensive work. So, if the depth of the weak-bearing layer is no more than 1 m, and underneath it there is a more “hardy” one, then during construction the layer of weak soil is removed and a sand substrate or concrete preparation is placed in the trench. Also, poor soil is sometimes compacted mechanically, replaced with a gravel cushion, or reinforced with special meshes. Experts, however, recommend in such situations to abandon the strip foundation in favor of a pile foundation.

The heaving of soil is directly related to its ability to hold water, and frost heaving is an increase in the volume of soil due to the expansion of water when it freezes.

Non-heaving soils: hard clays, low-moisture gravelly, sandy soils with deep groundwater.

Slightly heaving: semi-solid clayey; slightly water-saturated silty and fine sands, coarse soils with a clay and sand content of 10-30%.

Medium-heaving soils: refractory clayey soils, wet silty and fine sands, coarse-grained soils with a clay and sand content of more than 30%.

Highly heaving and excessively heaving: soft plastic clayey, silty and fine sands with strong water saturation.

On highly heaving soils, it is possible to build small (1-2 floors) wooden houses on a shallow strip foundation made of monolithic reinforced concrete. For heavier houses, a complex of works will be required to lower the groundwater level, organize drainage and water disposal.

The higher the groundwater level, the more heaving the soil will be, regardless of its composition. The groundwater level critical for foundation construction varies for different soils and is calculated using the formula: the lower limit of soil freezing (in meters) plus the following number:

• sands – 0.8-1 m
• sandy loam 1 – 1.5 m
• loams 2 – 2.5 m
• clay 2.5 - 3.5 m.

When groundwater levels are below the specified values, they do not affect the degree of soil heaving.

In general, the construction of a strip foundation on highly heaving soils with a high groundwater level is considered inappropriate: in such conditions, a pile-grillage foundation performs best.

When planning construction, it is best not to skimp on a professional soil survey on your site: this will help to avoid big problems in the future. The services of a specialist cost money, but the investment is worth it. Saving a house whose foundation has deformed due to errors in assessing the properties of the underlying soil will cost much more.

Preparing the base of the heads

For the convenience of subsequent construction procedures, the tops of the piles are equipped with special square plates (heads) measuring 250x250 cm.
They must be prepared accordingly:

Drill several holes (usually 3-4 pieces). They facilitate the procedure of attaching wooden frames with plumbing screws. The size of the screws is 10x120 mm.

To attach the harness to the heads, holes are made for self-tapping screws Source svaybur.ru

Waterproof the caps with roofing felt or innovative bitumen material. When cutting pieces for each head, make a margin of 20 mm per side: this makes fixing easier.

Thanks to waterproofing gaskets, protection is provided for wooden framing elements from the damaging effects of moisture. Its source is condensation that forms on a cold metal surface during temperature fluctuations. Every effort should be made to keep the wood dry at all times.

The waterproofing layer between the sole of the head and the beam prevents condensed moisture from penetrating the frame. This significantly increases its service life and prevents rotting. To prevent the waterproofing sheets from moving, the base of the cap is coated with bitumen mastic.

Waterproofing between the head and the timber is mandatory, otherwise, due to exposure to moisture, the strapping can quickly “wear out” Source stroy-dom-pravilno.ru

Preparation for work and selection of rolled metal

The technological process of strapping is associated with the arrangement of the pile site. The algorithm for preparatory installation work includes:

1. Conducting a site survey, marking pile points for drilling.
2. Installation of screw columns and leveling the height.
3. Pouring concrete mortar into the cavity of screw piles.

To create a single structure after installing the pile elements, there is no need for standing. The columns are not subject to shrinkage, so you can start tying without delay.

For a foundation protruding a meter or more above the ground surface, it is necessary to install an additional grillage or control stiffening rods at a height of 30–50 cm.

A good result is achieved by using black-rolled metal. Hot-rolled strips or I-beams are used for strapping.

For walls with a thickness of 250 mm, you should choose a profile 24P - 30P; for supports with a cross-section of 108 mm, rolled metal 14P is used.

The metal has significant weight. The weight of the prefabricated structure depends on the length of the channel and its weight. Sometimes it is advisable to use lifting construction equipment for installation, which can be difficult in small areas.

Before tying, it is necessary to level the surfaces of the supports. This is the main condition for installing the channel on screw piles.

Work technology

The operating algorithm is as follows:

1. Prepare the reinforcement - cut the rods into pieces of the required length using a grinder.
2. Smooth rods are bent, giving them the desired shape.
3. Place two corrugated fittings parallel to each other on the working surface.
4. The prepared squares are placed on the longitudinal rods and fixed by welding or tied with wire.
5. Turn the structure over and fix the two remaining longitudinal reinforcements.
6. The metal frame is coated with a hydrophobic composition.

The finished reinforced frame is installed inside the well and filled with concrete mortar. The rods for connecting to the grillage should protrude above the concrete surface.

Making a reinforcement cage for bored piles - in the video:

All the most important and useful information about the pile-screw foundation is presented in this section.