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How to make a foundation replacement under a wooden house. Replacing the foundation under a wooden house - methods, technical nuances How to replace piles under a wooden house

Sometimes owners of country houses are faced with the problem of subsidence of the foundation. This occurs as a result of changes in the underlying soil, construction work on the land or in the house itself. For example, the addition of the second or attic floor increases the load on the foundation, and if it was not designed for such a mass, it will begin to settle. In addition, improper installation of the base, lack of high-quality thermal and waterproofing leads to such problems.

To avoid the problems listed above, it is important to choose the right materials, install and finish the base. What foundation is suitable for a wooden house, read here. For minor damage, you can carry out cosmetic repairs or strengthen the base. But if the structure has already begun to subside, cracks have appeared in the base or the walls are warped, a complete replacement of the foundation under the house is needed. Otherwise, the building will soon collapse.

In the article, we will find out when you really need to replace the foundation under a wooden house, and when you can get by with a light repair. Consider how to change the foundation of the house with your own hands, if necessary.

Types of foundation damage

Minor damage includes chipped trim. These defects can be easily noticed and eliminated without problems. They do not affect the bearing characteristics of the structure, they simply violate the aesthetic appearance;
Moderate damage includes cracks that appear due to structural failure and ground subsidence. The most dangerous are vertical cracks and cracks in the form of zigzags;
Severe damage includes a large number of cracks, fractures in the base and warping of the walls of the structure. Then carry out strengthening or complete replacement of the foundation;
Fatal deformation mainly occurs in the old structure and foundation. There is nothing to repair here. It is necessary to completely disassemble the structure and build a new solid wooden house in compliance with modern building codes and regulations.

How to fix cracks in foundation

Cracks at the very beginning of formation can be easily repaired. Do not miss the moment and do not delay repairs, as the cracks will grow and increase. Then the damage from moderate to severe will develop. To determine the degree of danger of cracks, the rate of subsidence and the nature of the destruction of the foundation, beacons are made.

A little putty is applied to a clean, dry foundation wall, a straight line is drawn with a spatula and a mark is made up to 5 mm thick. Such a beacon will break with any movement of the surface. Instead of putty, gypsum plasters or plain paper are also used. But if the paper gets wet, it will no longer provide reliable results.

If the subsidence is temporary and does not pose a threat, the mark remains motionless. This means that the foundation has moved along with the soil and taken its place. In this case, cosmetic repairs of cracks can be carried out. To eliminate the defect, the crack is expanded, cleaned and sealed with a primer. The resulting seam is fixed with cement.

Strengthening and strengthening the foundation

Structural reinforcement is used if deformation is present, but the ground is stable. In addition, the foundation needs to be strengthened if an addition of another floor is planned. Strengthening will help the base to cope and redistribute the increased load. Then the structure will not collapse and settle. Strengthening includes the following actions:

A trench is made around the perimeter of the base. The surface is cleaned of earth, dirt, debris and dust;
Holes are drilled, the diameter of which should be 1 mm larger than the reinforcement. Reinforcement is hammered into the holes;
Make a reinforced belt. In several places, the reinforcement is welded to the installed pieces, and in the rest they are fixed with a wire;
The formwork is installed and the concrete mixture is poured. After it hardens, the formwork is removed. Then the structure is left to dry for another two to three weeks. During drying, the surface is covered with a film and periodically watered.

After installation, waterproofing and drainage system are made. To do this, along the perimeter of the foundation in the interval of 70-100 centimeters, you need to dig a trench 20-30 centimeters wide. The depth of the trench should not be lower than the level of pouring concrete. Geotextiles are laid at the bottom with an overlap on the walls. Gravel is poured from above and a drainage pipe is installed. The angle of inclination of the pipe is 5 mm per 1 m.

The pipe is covered with gravel from above, the protruding edges of the geotextile are wrapped and rammed with earth. The drainage pipe will collect water in the future and divert it from the house to a pit or a special well. To enhance waterproofing, you can cover the outer walls of the foundation with protective solutions, plaster, bituminous mastic or primer and liquid rubber.

Waterproofing can be done before the installation of the foundation. To do this, roofing material is laid at the bottom of the pit and formwork, the joints between the materials are coated with bituminous mastic. High-quality waterproofing will prevent the appearance of cracks and distortion of the walls. In addition, without proper protection, it will be cold and damp in the basement and on the first floor.

At the end of the work around the house and the foundation, blind areas are made to divert water from the building. They will not allow flooding of the basement and the building. The blind areas represent a horizontal strip 60-120 centimeters wide, which runs along the perimeter of the house at a slight slope. The path is made of concrete, crushed stone, paving slabs or stone paving stones.

Partial and complete foundation replacement

The replacement of the foundation is resorted to in case of serious defects and destruction of the structure. With partial replacement and cosmetic repairs, a part of the structure is disassembled, the deformed element is removed and a new one is inserted. Such dismantling can be done independently, but it is not suitable for every type of base. So, for example, a reinforced concrete strip foundation or a monolithic slab cannot be partially disassembled.

Partial dismantling also requires lifting the house and using special equipment. Therefore, the cost of work will not decrease significantly compared to the complete disassembly of the foundation. At the same time, partial replacement reduces strength and reduces the operational life of the base. In addition, it violates the integrity of the structure. Therefore, experts recommend resorting to the method of complete replacement of the foundation.

Complete replacement of the base is a complex job that is difficult to do on your own. It includes lifting and lowering the house, dismantling the old and installing a new foundation. Let's look at how to properly raise a building and how to replace your foundation under a wooden house.

The technology of raising a wooden house

To raise a house from a bar or log, you will need at least four jacks with a lifting capacity of 10 tons each. Before starting work, check and evaluate the corners of the building. It is important that the frame does not fall apart when moving. Window and door frames are removed from the house, furniture and other items are pulled out. It is important to leave the room empty. To prevent damage to the roof, the chimney is separated from the ceilings.

A trench is made around the house to make it easier to access the foundation. Jacks are installed along the long walls of the house at a distance of 0.5 meters from the corners of the building. Under each jack they make a solid platform with parameters of 50x50 centimeters. The bases can be deepened so that the equipment does not slip.

In the corners of the house and at the intersections of the walls, temporary supports are equipped. The materials used are timber, logs or bricks. The log house is raised simultaneously with support on the lower crown of logs. To prevent the lower crown from bending, it is pulled together with a steel hoop. Or when lifting at the bend point, use another jack.

The first rise should not exceed two centimeters. The structure is installed on temporary supports, then the house is raised another 1.5-2 centimeters. Thus, the frame is gradually raised up to 10-15 centimeters and securely fixed on temporary supports.

How to dismantle the old and install a new foundation

To disassemble the foundation from cement mortar or rubble materials, wooden wedges are hammered into the seams of the base. To work, you will need a puncher, sledgehammer, crowbar, hammers and other tools. It is necessary to dismantle the structure to the ground.

After dismantling the old foundation, they begin to install a new one. The space is cleared, a pillow of gravel and sand is made, formwork and a reinforced grating are installed. The formwork is poured with concrete and a waterproofing material is laid on top in several layers. Ruberoid is well suited for this. During work, take care of niches for jacks to safely lower the house.

The frame is lowered smoothly and gradually also by 1.5-2 centimeters. After that, the foundation is finished, which includes the arrangement of waterproofing and insulation, cladding, drainage and blind areas. Niches for jacks close up with bricks.

Replacing the old foundation, raising and lowering the house, installing a new foundation is a laborious and dangerous process. It is important to carry out quality work and observe safety precautions. To get a reliable and solid foundation, to avoid problems during construction work, contact the professionals!

Replacing the foundation under a wooden house

Replacing the foundation under the house: types of damage to the base, eliminating cracks, strengthening and strengthening, partial and complete dismantling, dismantling of the old and installation

Raising the house on jacks.

Over time, the building may shrink. This is due to a violation of construction technology, natural aging, geological and climatic conditions. Raising a house with a foundation replacement is a fairly common option for major repairs. There are other ways to restore the integrity of the base of the building. Before starting work, the main thing is to correctly determine the degree and cause of shrinkage of the building. Sometimes it is required to change the entire structure of the base under the house.

The most popular method of replacing the foundation is to raise the house on jacks. They may need from 2-4 to 10-12 pieces. Raise the building by installing jacks on both sides of one wall. Diagonal lifting is not allowed.

In one run they reach a height of 1.5-2 cm, no more. Temporary supports are immediately inserted into the resulting space. Additional jacks are installed in the places of deflections of the lower edges of the log house.

Another method involves removing a layer of soil under the house, 200-250 mm thick. After that, the wooden crowns are replaced and the base of the house is repaired.

Time-consuming and requiring special skills methods include the complete dismantling of the walls for a convenient approach to the foundation. After that, the base structure is repaired or completely replaced. Then the walls are assembled in a new way, replacing rotten and deformed elements.

If the wear is minor, a cosmetic repair may be sufficient. This is the cheapest recovery method.

What kind of base to choose

It happens that the old foundation is out of order and it needs to be completely replaced. Before replacing the foundation under an old wooden house, you need to decide which type of foundation is best suited for given geological conditions and the type of building.

Types of foundations and their characteristics are presented in the table:

1	Tape	It is a monolithic or prefabricated concrete belt capable of withstanding significant loads. For small wooden buildings, a shallow base is sufficient. But if the site is dominated by heterogeneous soil or watered, prone to frost heaving, then you need to choose a different type of foundation.
2	On screw piles	Screw piles are buried in the ground. They can be combined with a grillage or operated without it. This is an inexpensive type of base, available for quick do-it-yourself installation. Suitable for light buildings built in areas with a difference in relief, a deep level of freezing of the earth, with small waterlogged areas.
3	On bored piles	Allows you to reduce land work. It is a well filled with cement mortar, interconnected by concrete beams or a slab.
4	On brick, stone, concrete pillars	The pillars are mounted in increments of 1-2 m, installation is mandatory at the intersections of the walls and in other places with a maximum bearing load. It is a reliable support for small light buildings.

The type of foundation for a wooden house is chosen depending on many factors. If it is difficult to make a decision and calculate all the loads on your own, it is better to turn to professionals who will help you make the right choice.

Foundation replacement

Replacing and repairing the foundation will require some knowledge and patience. In order not to completely destroy the building, you need to do the work slowly, clearly adhering to the technology.

Jacks can be rented at the railway depot, they must be designed for lifting loads weighing 10 tons.

In the form of lining elements, bricks, strong bars and boards can be used.

Before lifting the house building, lighten its weight as much as possible. Disassemble the floors, take out the furniture and all household items.

Under the jacks, a base is made in the form of a square of wood with sides measuring 50 x 50 cm.

Calculations

In order for the new foundation to serve as a reliable foundation for the building for a long time, you need to correctly calculate its parameters.

When calculating, you need to take into account:

soil freezing level;
proximity to underground sources;
seismic activity;
relief of the site;
soil type;
a lot of house building.

Under the bearing walls, the foundation is buried at least 500 mm, under the partitions at least 400 mm.

Jacking up the house

Make a platform for jacks. Install it, slightly deepening into the ground, at a distance of 50 cm from the corners of the building. Jacks are fixed on a wooden stand.

The beam as lining elements holds the structure of the house.

At the same time, on both sides, a lift is performed to a height of not more than 2 cm in one go. Jacks are placed in places where the wood has not lost its strength. In rotten places, it is impossible to install devices for lifting.

For the correct transfer of the load to the logs, it is necessary to provide for the installation of metal plates that perform the function of a gasket.

Strong backing elements are immediately placed in the resulting gap. Alternately raise all the walls until they reach the desired height. Check the stability of the building, it should not be mowed. Firmly fix the desired level by installing lining elements.

Dismantling of the old foundation

After raising and fixing the wooden house, the foundation is repaired or dismantled. These works are quite easy to do with your own hands, you will need a few assistants and simple tools: a crowbar and a sledgehammer.

If you disassemble the old foundation carefully, then the materials remaining intact can be used for further construction work.

What you need to know

The degree of shrinkage of the house depends on the type of soil and the level of location of underground sources. If they are close to the surface, you need to provide a drainage system around the perimeter of the house.

If the soil is prone to landslides, it is strengthened. To do this, the area around the foundation is poured with a mixture of liquid glass with water, or small wells are drilled and resin is poured into them.

If groundwater is close, winter heaving of the soil will be much higher. Freezing groundwater increases in volume and pushes everything that is in it out of the soil. When melting, the volume of water decreases, and shrinkage occurs.

Foundation installation on screw piles

If a decision is made to build a new foundation on screw piles, you need to calculate their length and diameter. It is not worth saving on the material, since the reliability and safety of the house will depend on its quality.

To build the foundation of a small wooden house, you will need 8-12 screw supports.

Step-by-step instruction:

After raising and fixing the housing construction, I-beams are laid under its load-bearing walls and partitions. They are cut off by 5-7 cm more than the estimated length. In the future, they will perform the function of a grillage.
In pairs, at a distance of 300-400 mm from the walls, screw piles are twisted, which are the support for the beams. Make sure that the structures are clearly level.
To give strength and protection against corrosion, the cavity of the pile is poured with a concrete solution.
A cap is put on the upper edge of the support, and the grillage channel is already attached to it.
Dismantle the old base.
Carefully lower the house.

Raising a house.
The columnar base is mounted using the same technology as the installation of the screw foundation. The only difference is that you need to dig holes for the pillars, which are subsequently poured with concrete or laid out with bricks.

Installation of strip foundation

They prepare the site, remove construction debris, the root system of plants, sweep away dust.

Instructions on how to change the foundation of an old wooden house with your own hands:

They dig a pit below the freezing level of the soil and below the location of the old foundation. The shape of the trench should be U-shaped so that it is convenient to bring out the reinforcing frame and make it a bundle.
Sand is poured to the bottom, with a layer of 150 mm. Moisten, compact. Pour a layer of rubble, tamp it well.
Metal rods are connected, with a section of 12-16 mm in two longitudinal rows connected by vertical jumpers.
Formwork is made from boards, it will serve as a form for pouring cement mortar.
Pouring concrete solution. At the same time, openings are provided for installing jacks for lowering the building.
After its complete hardening, the formwork is dismantled.
Temporary supports are attached to the poured foundation. Starting work on replacing the foundation on the other side.
Openings for jacks are laid with bricks.
Check the integrity of the lower crowns and floor boards. If there is damage, it is necessary to repair the damaged elements. Cut out rotten and damaged areas, replace them with new ones.
Carry out work on waterproofing the foundation and basement of the building.
Gently and gently lower the house onto the new foundation.

There is another technology, according to which, first, the support posts are poured in the corners of the house building, and then, after drying, the house is supported on them and a concrete tape is mounted around the entire perimeter. All other steps follow the sequence described above.

How to restore and raise the house, you can watch the video:

Replacing the foundation is a work of increased complexity. You need to really assess your strengths and skills in the performance of construction work. If a mistake is made, workers may suffer or house construction may collapse. If there is not enough strength and knowledge, it is better to hire professionals with experience in this field.

Any reliable and durable wooden house will eventually need a major overhaul. If, during the construction of the foundation in a new house, violations of technology were made, then the likelihood of large-scale restoration work increases significantly. An incorrectly created base affects the balance of window and door openings, and contributes to cracking of the walls.

When such “bells” occur, urgent action is required. Replacing the foundation is the most rational method, but it is important to pay attention to the following aspects:

when doing the work yourself, you will need specialized tools, you should take care of this in advance to find a complete set;
after the old foundation is dismantled, you need to install a more reliable foundation of a different type (this is a difficult job, so the help of professionals may be required);
it is worth making sure that the house itself will still serve for a long time.

What does strength depend on?

The state of the foundation is significantly affected by changes in the soil, in particular, its bearing characteristics. They occur mainly due to the excess of the permissible load on the foundation and the subsequent loosening of the earth under it. The total load is increased by outbuildings standing nearby. This leads to skew and subsidence of the main structure, since under a significant weight the soil is pressed through.

Foundation replacement may be necessary due to erosion of the soil due to rising groundwater or improper water drainage.

Reducing the strength of the base material is another negative factor. This is possible due to an incorrect determination of the freezing depth, an unsuitable type of foundation, and the use of poor quality materials.

Base selection

It is important to understand that the replacement of the foundation of a wooden house should be carried out after the completion of all preparatory work. First you need to choose the design of the new base. The tape type is optimally suited for large heavy buildings. The screw base will perfectly withstand the construction of the type of a country house. Among the advantages it is worth noting the possibility of application in any areas. Also, screw piles are distinguished by the possibility of repeated use and relatively low cost.

The column base is used for medium-sized houses. Despite its apparent simplicity, it has gained popularity due to its reliability. The design consists of several pillars installed at the junctions of the walls - these are areas with maximum load. Pillars are made of stone, concrete or brick. It is worth noting the need for a mandatory step of 1-2 meters. The pile bored basis also refers to the foundation of a columnar type. It got its name because of the asbestos-cement pipes used as load-bearing elements and filled with a specialized mixture. Soil with elevated water levels is the best place for such a foundation.

The foundation of the house indicated above is also in demand, the replacement of which involves the use of piles. It requires less investment, while in the end its strength is comparable to a concrete base. Piles are screwed into the ground using levers. Their level should exceed the freezing depth. It requires alignment at a certain height and the use of a belt made of a channel beam. This type of foundation is convenient on sagging and weakened soil types.

Base subsidence

Settling may be progressive or temporary. In the definition, special beacons made from different materials will be useful. It should be borne in mind that if water gets on paper options, they become unusable. Gypsum plasters are also used as beacons. In their absence, it is possible to apply an even strip of putty on the wall and put a mark, so the places of crack expansion and the determination of the rate of destruction will be identified in time.

Equipment

Although the work is on a large scale, you can not resort to renting expensive equipment: several powerful jacks (at least 4) with a lifting capacity of around 10 tons will be enough. You also need to have auxiliary wedges, scrap and a sledgehammer at your disposal. To create a support, various logs, boards and a lot of bricks are required. Before mounting the jack, a strong platform is knocked down, with sides of at least half a meter each. It will require a steel plate with a thickness of 6 mm or more.

Replacing the foundation under a wooden house means freeing it from heavy objects and furniture. Next, the coating is removed and the floor itself is disassembled.

How is the lift

After completion of the preparatory work, you can install jacks. They are placed along the perimeter of longer walls, with a mandatory indent from the corners. Pre-designed sites must be stable (perhaps a slight depression in the soil).

It is worth paying attention to the fact that lifting the house alone and replacing the foundation with piles is possible. There should be one person per jack. Careful lifting of the building can only be carried out with this approach. The lifting height at a time should be no more than 2 cm. If gaps occur, prepared supports are used to close them. Requires simultaneous execution of all actions.

A significant sagging of the lower rims during the lifting process indicates a lack of jacks. But further actions should be as careful and accurate as possible in order to avoid displacement of the structure.

Foundation replacement: dismantling

After the house is raised and firmly fixed, the old base is removed. Some elements may be useful for secondary use, so they should be folded separately. After dismantling, a deeper trench is dug in the form of the letter P. Thanks to the use of this form, it is possible to connect sections of the base laid at different times. If you need an extension in the future, it is better to immediately lay the foundation for it, so that in the future it will not be necessary to replace the foundation under the house due to the increased load.

Completion of works

It will take about two weeks to completely solidify the poured base, then it is covered with boards and temporary supports made of brick or wood are placed on top. After replacing the foundation under the wooden house, it is repeated on the other side. Long sections of walls require digging straight short trenches, followed by joining with reinforcement.

After completion of all work, the lower crowns are checked for quality, if necessary, they must be replaced. Further, the structure gradually descends evenly from all sides, after which the replacement of the foundation can be considered complete.

A common problem of old wooden houses is the high wear of the foundation. Such changes are visible to the naked eye: the house is squinting, walls or doorways are sagging. If such problems are multiple in nature, it is urgent to repair the foundation. The house is in danger of destruction if the work is delayed for another couple of years. For this reason, the restoration of the foundation is in many cases a relevant and important task. Before laying the foundation for an old wooden house, it is necessary to conduct an inspection and assess its condition. A thorough analysis will determine the future work.

Foundation inspection

When evaluating the foundation, it is worth adhering to a certain technology. Foundation inspection is carried out as follows:

a trench 50-70 cm wide is dug around the foundation;
foundation material is determined;
inspected for damage.

Attention! With minor damage, you can do without replacing the base: it is enough to strengthen the existing foundation of the old house.

Foundation varieties

After inspecting the old base, you need to decide what type the new one will be. The choice of construction depends on many factors, such as the type of soil and the weight of the house. As a rule, the following types of foundation are used in the construction of wooden houses:

stone (more often - brick) - brick is an inexpensive material, but it collapses from moisture;
reinforced concrete - the most durable of all types of bases, it can be tape and monolithic;
pile - the foundation, constructed from metal piles, is very practical and prefabricated;
wooden - oak columns (decks) are located around the perimeter of the foundation, such a base is very susceptible to fungi and moisture.

The modern variety of materials makes it possible not to use obsolete types of foundations in construction. The most practical and durable options are reinforced concrete and pile foundations. Some foundations are well enough to strengthen.

house lift

When the question arises: “how to make a foundation for an old house?”, You immediately need to decide how to raise the house. These works are carried out regardless of the type of future foundation of the building.

Preparatory work

To raise an old house, it is not necessary to use expensive special equipment. The most democratic option is jacks. To determine the load capacity and the number of jacks, you need to calculate the approximate weight of the house. All furniture and household items are taken out of the building - this will ease its weight.

To work, you will need a large number of wooden or brick support pillars, they are prepared in advance. The height of the supports should correspond to the height of the future foundation. The number of supports depends on the length of the walls. To regulate the minimum difference in the height of the supports, you will need linings, the best option is boards.

In the process of lifting, the lower crowns of the house are the most vulnerable spot. To protect the logs from spilling and cracking, they are fastened with metal brackets. If the structure of the house has an old foundation, it is necessary to destroy its outer hoard, approximately 50 cm along each side. This is done for further installation of jacks. To figure out how to pour a foundation under an old house, it is worth knowing all the intricacies of raising the structure.

Installation of jacks

Jacks put a lot of pressure on the logs, so they are placed on undamaged logs. Jacks are installed as follows:

under the place where the jack will stand, a strong support is laid in the form of sheet iron, thick plywood or a substrate made of timber (50x50 cm in size);
the most sagging corner of the house is determined and under it, on a prepared support, a jack is installed;
install jacks at subsequent corners.

Note! It is problematic to raise an old house with your own hands alone - 2-3 or more workers perform work to secure the work.

lifting process

The rise of the house begins from the most sagging corner. All actions are performed very smoothly so as not to damage the walls of the house. In the first approach, a rise of 2 cm is performed, this will prevent cracking of the walls. Wooden bars or planks are placed in the resulting gap.

When the first corner is raised, the subsequent ones are raised one by one to the same height. Supports in the form of planks are laid around the entire perimeter. The lifting is carried out gradually, placing supports in the gap to ease the load on the jacks.

After the house is raised to the desired height, they put brick or wooden supports-pillars. As well as for jacks, support platforms of solid material should be prepared for support pillars. Only after that can repair of the old foundation be started.

The whole process of lifting the house is carried out within a day. The last stage is the preparation of a place for the future foundation. If the house is dilapidated, it is raised with extreme care.

Destruction of the old foundation

After raising the dilapidated house, they begin to destroy the old foundation. The traditional and less expensive way is to work with a sledgehammer and wedges. Wooden stakes are driven into the seams or cracks of the foundation with a sledgehammer. For the destruction of the remaining elements of cement, a perforator and scrap are suitable.

A shovel is used to clean up the debris. After the foundation of the old house is destroyed, they begin to prepare a place for a new foundation.

Important! In the course of the destruction of the base of the building, brick or wooden supports are installed around the entire perimeter.

Filling the strip foundation

The most reasonable option for one-story wooden buildings is a strip reinforced concrete foundation. It is suitable for any kind of soil. The construction of such a foundation is performed as follows:

Trench dig. The basis for the new foundation should be 10-20 cm wider than the previous one. If in the future it is planned to build on the site of other buildings, the foundation should be poured for them as well;
A U-shaped trench is created under the longest walls;
Sand is laid in the first layer in the trench (10-15 cm);
The next stage is the installation of a reinforcement frame;
formwork assembly;
Laying inside the formwork waterproofing;
Solution pouring.

After the solution has completely hardened, boards are laid on one section of the foundation, on which temporary supports are laid. All sections of the base are poured one after the other. The reinforcing mesh of each new section of the foundation is connected to the outlets of the rods of the previous sections.

With another method of building a foundation, the corners of the structure are first poured. In the formwork, limited sectors are created at the corners of the proposed foundation. They fill up first. After the solution has hardened, all remaining sections of the base are poured.

After pouring, the openings for jacks are laid with brick or mortar. When the base is completely solidified, re-examine the lower logs and replace if necessary. The final stage of work is the installation of the house on the foundation: the work is carried out smoothly, the structure is gradually lowered by 3-5 cm.

Replacing the old foundation with screw piles

With a fast speed of work, the installation of a pile foundation takes a day. This type of house foundation is quite suitable for sandy and swampy soils.

Before buying piles, you need to calculate the weight and area of \u200b\u200bthe house and study the type of soil under it. The average bearing capacity of screw piles is from 5 to 14 tons, depending on the span of the blades and the diameter of the pile itself.

Work on the installation of the pile foundation is performed as follows:

raise the house with jacks;
mark places for future piles (more number falls on the places of load-bearing walls and corners of the house);
piles are installed manually or with the help of equipment (deepening of structures above the level of soil freezing);
after screwing in all the piles, they are combined with a metal frame by welding;
the final stage is the installation of the house on a pile foundation.

To reduce heat loss and improve the appearance of the building, the structure is covered with bricks or decorative panels.

Results

To arrange a new foundation under your house, you first conduct a series of studies. They are aimed at determining the state of the foundation. You also need to know the intricacies of lifting a building with jacks. They begin to lift from a more sagging edge. Care must be taken when working with the lower crowns. Experienced builders use brick as a material for temporary supports.

Replacing a strip foundation is easier than other types of foundations. It is necessary to competently approach the formwork device and concrete pouring. When installing a house on a foundation, it is also worth considering several features of the process.

We build a house from foam blocks with our own hands
floating foundation
Do-it-yourself formwork for the foundation
The foundation for the stove in the bath

Types of foundation damage

Minor damage includes chipped trim. These defects can be easily noticed and eliminated without problems. They do not affect the bearing characteristics of the structure, they simply violate the aesthetic appearance;
Moderate damage includes cracks that appear due to structural failure and ground subsidence. The most dangerous are vertical cracks and cracks in the form of zigzags;
Severe damage includes a large number of cracks, fractures in the base and warping of the walls of the structure. Then carry out strengthening or complete replacement of the foundation;
Fatal deformation mainly occurs in the old structure and foundation. There is nothing to repair here. It is necessary to completely disassemble the structure and build a new solid wooden house in compliance with modern building codes and regulations.

How to fix cracks in foundation

Strengthening and strengthening the foundation

A trench is made around the perimeter of the base. The surface is cleaned of earth, dirt, debris and dust;
Holes are drilled, the diameter of which should be 1 mm larger than the reinforcement. Reinforcement is hammered into the holes;
Make a reinforced belt. In several places, the reinforcement is welded to the installed pieces, and in the rest they are fixed with a wire;
The formwork is installed and the concrete mixture is poured. After it hardens, the formwork is removed. Then the structure is left to dry for another two to three weeks. During drying, the surface is covered with a film and periodically watered.

Partial and complete foundation replacement

The technology of raising a wooden house

How to dismantle the old and install a new foundation

Masters of the MariSrub company will qualitatively and quickly replace the foundation, install a new foundation for a wooden house, select materials and finish it. We carry out waterproofing and insulation, organize a drainage system and blind areas. As a result, the foundation will last a long time!

Today, many developers choose to build a columnar foundation for their house due to its cheapness. In addition, such a foundation is built quite quickly - in just 1 day. Such a foundation is considered ideal for the construction of garden and country houses, a light bathhouse, residential buildings from a small bar on non-rocky soil. But there are cases when the columnar foundation begins to quickly collapse, fall on its side or bulge. Under such conditions, the only way to prevent further subsidence of the base is to replace the columnar foundation.

The need to replace the column foundation

Many rural houses that were built in the last century have a primitive columnar foundation as their foundation. Such an ancient structure is made of brick or stone, often quite dilapidated, unreliable and outdated. They require immediate replacement with a more durable, high-quality and reliable foundation. The main reason for the destruction of the columnar foundation is sediment, which naturally causes a change in the position of a wooden house, the appearance of cracks in the walls, jamming of windows and doors.

This process comes from various physical, mechanical and hydrological changes that take place in the lower soil and reduce its bearing capacity. The foundation actually ceases to fulfill the tasks assigned to it. Often, changes in soil properties are caused by construction work that is carried out in the backyard. But such problems are inherent not only in old houses.

And when installing a new house on a columnar foundation, the latter very quickly begins to squint or sag and pull the house along with it. Especially when it comes to large and heavy log houses (9 by 9 meters or more) and cottages. In these cases, such a foundation is categorically not recommended to be used, because there is a significant load, and here it is more rational to equip a pile-screw or strip foundation. It is also irrational to build a columnar foundation on heaving soil.

I would like to immediately make a reservation that this is most often not the fault of the masters who carried out the construction. This is due to the phenomenon of heaving of the soil during its thawing after winter freezing. The earth thaws earlier on the south side of the house, pushing up the south posts, which end up on loose, sized earth, while the north posts stand in place on the hard frozen ground.

Even if you dig 2 meters into the ground and pour concrete asbestos pipes that are strong in compression and bending, they will not be able to withstand heaving of the soil. All the same, the level of the columns along the horizon will be violated, and the house as a whole will be skewed. In this case, the foundation cannot be repaired and it is pointless to try to align the foundation pillars, you need to remember: if the blocks have moved at least once, then they will change their horizontal position every year after winter, and it needs to be replaced as soon as possible.

In such cases, the only correct solution is to replace the foundation. This procedure is rightfully referred to as radical measures designed to restore the safety and reliability of the house, as well as increase its lifespan. However, it is worth remembering that it is advisable to replace the base for buildings whose construction, after replacing the soil, can last for several more decades.

Methods for replacing a columnar foundation

As a rule, the replacement of a column foundation with another one takes from 5 to 10 days, and the lifting of a residential building is carried out from below, which allows workers not to dismantle the floor, thus facilitating work. But the replacement of the base during the subsidence of the internal walls of a residential building requires to open the floor covering to correct the defect.

There are several methods for replacing the foundation under a wooden building:

Cosmetic repair is the simplest technique that does not involve large financial investments. In this situation, you simply need to cut out the rotten area, and instead insert a suitable wooden element. However, it must be borne in mind that with such a partial replacement of the base, the integrity of the house is inevitably violated.
The dismantling of the walls is a type of construction work, which involves the complete dismantling of the walls, after which the lower crown of the log house is replaced. The method is reliable, but it requires a fair amount of patience and time from the masters to disassemble and assemble the structure.
Dismantling the foundation. To do this, you will have to remove a layer of 20 centimeters, replace the wooden crowns and then restore the base under the house.
Replacing crowns by raising a building with a jack is considered the most popular method, according to reviews of replacing a columnar foundation, as it allows you to replace the foundation quickly and efficiently.

Choosing a new foundation for the house

It is important to understand that the procedure for replacing the foundation of a house is a complex process that requires careful preparation. To begin with, it is worth deciding on the design of the future foundation, which will replace the old columnar foundation. There are such types of foundations that are suitable for wooden houses:

The columnar foundation is a system of pillars that are installed in places of maximum load - the intersection points of the walls. The pillars are made of stone, concrete or brick and set at a distance of close to 1-2 meters. It is adapted to support light residential buildings with wooden, frame or panel walls, which do not create significant loads on the foundation. Despite the simplicity, columnar foundations can be chosen to provide reliable support for a country or garden house, as well as other outbuildings.
A bored pile foundation is a type of columnar foundation, only asbestos-cement pipes are used as load-bearing elements, which are filled with a special mixture. The design of such a foundation consists of piles and a grillage that connects them. Bearing elements are similarly located under the most significant points of the house, for example, in places where the main walls intersect, and at the corners of the building. A bored pile foundation is considered optimal for buildings on ground with high water.
The pile screw foundation is considered the most interesting type of foundation for the house, as it was originally intended for military purposes. Today, such a foundation is widely used in civil engineering and is valuable because you can use it on any terrain, even on an uneven site with height differences. In addition, the low price of replacing a columnar foundation with a screw pile foundation and the possibility of repeated use of screw piles are additional advantages of such a foundation. The disadvantage is the hiring of special equipment.
The strip foundation allows you to build heavy houses and at the same time provides high reliability and security of the house. The most popular shallow strip foundation is monolithic and prefabricated. Prefabricated structures are made of concrete based formwork, monolithic - from blocks of reinforced concrete and concrete.

Replacing the columnar foundation with your own hands

Of course, you can replace the old columnar foundation yourself, but you must be confident in your own abilities. In this case, you will need the information below, as it allows you to navigate the issue of replacing the foundation and control the situation.

Preparatory work

Despite the creation of a reliable foundation and the correct calculations when laying it, sometimes small cracks appear on the facade of a residential building, window sills, plinth and other horizontal lines are bent. This indicates the subsidence of the house under the columnar foundation and requires an immediate replacement of the base.

However, before starting work, you need to make sure that the deformation of the base has already stopped. To do this, on a surface moistened with water, install gypsum beacons across the crack. Watch these lighthouses for two weeks: if cracks do not form on them, then the deformation of the house is over, and you can safely proceed to replace the column foundation with your own hands.

You can raise a house without special construction equipment, you just need to use hydraulic jacks, which are able to develop sufficient force, which allows you to lift a load of 10 tons. In their absence, it is not advisable to think about buying such equipment, since this equipment can be rented at any railway depot.

You will also need steel scrap, a sledgehammer, wedges - tools that are mostly needed to dismantle the old foundation. To create temporary supports, you can use massive beams, chocks, bricks, as well as boards of various thicknesses that act as spacers. As a platform for installing a jack, you can use bars and boards knocked into a shield, or any durable material.

For uniform transfer of force from the jack rod to the lower rims of the house, it will be necessary to cut a steel plate that has a thickness of at least 5 millimeters. If you have to work with a columnar base with a pickup, then before starting work, the latter will have to be disassembled. Also, at the preparation stage, it is recommended to remove all heavy things, furniture from the house and disassemble the floors.

The rise of a wooden house

Raise the building with jacks. They are usually installed on both sides of the house at a distance of 0.5 meters from its corners. Jacks allow you to evenly raise the house, otherwise the logs of the lower strapping will bend during uneven lifting, which will lead to their separation and subsequent breakage. The jack should be installed in places where the tree is not damaged by rot.

Remember that it is necessary to install spacers in the form of steel plates so that the force is correctly transmitted to the logs from the jack rod. Instead of metal plates, you can take pieces of wooden blocks. Jacks are fixed on a pre-prepared support platform, if necessary, they need to be buried in the ground to give it maximum stability.

The number of pieces of logs that are used to construct temporary supports depends on the chosen technology for lifting the house. If you plan to immediately raise the entire building, then the number of temporary supports should be twice the number of foundation pillars. The support is assembled from pieces of logs, like an ordinary well

The height of the supports should exceed by 10-15 centimeters the difference in the distance from the soil surface to the height of the jack, because when the house is raised, the supports will settle and be pressed into the ground. Raise the house, if possible, from both sides at the same time, evenly, no more than 1.5-2 centimeters at a time. The result obtained is immediately fixed with temporary supports.

If you find bends in the lower crowns as a result of lifting the house, additional jacks should be installed. At this stage, it is recommended to control the process so that the house does not move to the side, because when lifting, its center of gravity will change.

The wall must be raised to a height of at least 6 centimeters, the rotten extensions removed and the building lowered onto the trimmings of the beams, which are placed on temporary supports. Tow is laid between the logs and beams, which is treated with an antiseptic, in width, which is equal to the double thickness of the beam. Brick battle and gravel of 10 centimeters are poured under the proposed base tape.

When you have raised the house to a sufficient height and secured it securely with temporary supports, you can begin to dismantle the old columnar foundation. It is necessary to break the rubble and brickwork using chisels, crowbars and other tools that are easy to use. Old poles are dug out or pulled out of the ground, swinging them in different directions. You can use some of the materials that have retained their quality indicators to form a new base.

Building a new foundation

Consider replacing the columnar foundation with a strip shallow foundation, which is best suited for one-story houses. As the name implies, this type of foundation is considered to be something between a non-buried and a capital buried strip foundation. It consists of monolithic reinforced concrete strips that run along the perimeter of a residential building and in places where load-bearing walls will subsequently be located.

Now let's talk about the advantages of a tape shallow foundation:

Tape shallow foundation is an economical solution. If you compare this foundation with recessed types of foundation, then it will cost you two to three times cheaper.
A shallow foundation requires less work than a deep foundation. This includes both modest earthworks and the ease of arranging formwork. Therefore, the replacement time of the foundation is significantly reduced.
A shallow foundation of a strip type allows, unlike non-buried foundations, to make a small basement in a residential building, and it is also less prone to heaving phenomena.

The construction of a new foundation should begin with excavation: dig a trench, the depth of which must necessarily exceed the depth at which the sole of the old foundation was located. A U-shaped trench is dug - this is necessary to form a frame with reinforcement to combine all sections of the foundation into one rigid structure.

If it is planned to erect new buildings adjacent to the house, then it is necessary to dig a trench, based on the project documentation. At the bottom of the trench, arrange a sand cushion. Then proceed to the manufacture and installation of formwork. The easiest way is to make it from boards that are planed on one side. They are easily knocked into shields of the desired size. In this case, the cost of replacing the columnar foundation will be lower. For their installation, spacers and support stakes are used, which must be driven in along the perimeter of the trench.

Carefully check the correct vertical and horizontal position of each shield. Then you need to waterproof the internal parts of the formwork with roofing paper or other material and proceed to reinforce the new shallow foundation. For this, steel reinforcing bars are used, which have a diameter of about 14-16 millimeters. The rods are tied into a frame using smooth rods with a cross section of 8-10 millimeters.

At this stage, it is very important to maintain the distance from the longitudinal bars to the future surface of the strip foundation. Usually it is taken equal to 5 centimeters - this is enough to provide reliable protection of the metal from corrosion. When the frame is ready, you can fill the formwork with concrete. At the same time, avoid the formation of air voids in the solution, so compact the solution every 200 millimeters.

The formwork can be removed 3 days after the concrete has been poured. Then the upper and side parts of the foundation should be waterproofed with roofing material or mastic. Cover the sinuses with sand and protect from the outside with a blind area. After the concrete has acquired sufficient strength (about two weeks), it is necessary to lay boards on the first element of the strip foundation, on which temporary supports should be installed.

New foundation load

After installing a new foundation, you can begin to load it. Proceed according to the scheme for replacing the columnar foundation - simultaneously with two jacks or each of them in series. Raise the corner of the building until the wedges are free, carefully pull them out, then gradually unload the jacks, lowering each corner of the building onto a new waterproofing foundation.

When loading a new foundation, check the marks of the top of the base and, if necessary, use antiseptic impregnated wood gaskets or corrosion-protected metal elements if, after applying the load, the top mark is lower than required. Or trim the lower crown if it turns out that the top mark is higher than necessary.

Thus, if you find that the old columnar foundation began to collapse, cracks appeared on the basement of the house, and the building itself began to squint to one side, you should immediately replace the old foundation. You can choose the type of a new foundation among several options - a column foundation similar to the old one, a bored pile foundation, a screw pile foundation or a strip foundation. But it is most preferable to equip a shallow strip foundation.

Built in the middle or even at the beginning of the last century, wooden houses regularly serve the current generation of owners. But there is no escape from the destructive action of time - the age of buildings that have witnessed an entire era shines through skewed windows and doors, a sagging base, leaning walls. However, plans for new construction should not be rushed. Very often, the fault of the unsightly appearance of a wooden house is a dilapidated foundation. Its renovation will provide the building with a second youth, and, perhaps, your grandchildren will also live in it.

Factors indicating the need for repair or replacement of the foundation

Before proceeding with restoration work, it is necessary to understand the reason for the destruction of the foundation, how serious the damage is, and also determine how the affected building can be reconstructed.

Brick foundation that needs to be completely replaced

Causes of damage to the foundations of wooden houses

In order to prevent such a problem in the future, it is necessary to deal with the factors that lead to the destruction of the foundation. And this happens for several reasons:

geological and hydrological changes that lead to subsidence or displacement of the soil under the building;
violation of construction technology and the use of low-quality materials;
lack or improper operation of the drainage system;
time factor - even high-quality materials lose their performance properties over the years;
weighting of the structure due to additional superstructures.

It is quite simple to determine whether the drawdown of the house is observed in the present time or the foundation has found new points of support. To do this, beacons made of drywall or paper are arranged in the most loaded places. Their damage indicates that the destruction process continues.

What are the deformations

The second thing to do in the research process is to determine the degree of destruction. The complexity of the restoration work depends on this factor. Conventionally, 4 types of deformations can be distinguished:

Small defects that manifest themselves in the peeling of the foundation finish. As a rule, the strength of the base does not suffer from this, and problems can be fixed without any problems.
Peeling of plaster, as well as small cracks, are easily repairable defects.
Medium damage, which is indicated by cracks in the base, appearing as a result of its displacement. To reveal how much the subsidence of the foundation progresses, a layer of putty is applied to the problem area. A crack that appears at the slightest deformation can tell about the rate of deformation, as well as its nature and direction of displacement.
Cracks that are initially stopped from spreading can be repaired with mortar
Significant or catastrophic damage resulting from significant subsidence, displacement, or failure of a foundation. They are revealed in the violation of the geometry of the walls, the appearance of large gaps between the crowns, the distortion of windows and doors. Problems of such a plan lead to the impossibility of operation or the complete destruction of the house, so an urgent strengthening or replacement is necessary.
If the deformation of the foundation can lead to the complete destruction of the building, repair work should begin immediately
Irreversible consequences. If the moment is missed, then repairing the house is likely to be unprofitable. In this case, they decide to demolish the building and build new housing.

After carefully analyzing the nature and degree of destruction, a decision is made on how to carry out the reconstruction of the foundation. If deformations can be eliminated and prevented in the future, then the foundation can be strengthened. Otherwise, it will need to be completely replaced.

In some cases, it is impractical to repair a house - it is easier to build a new one

Strengthening or replacing the foundation may be required not only when it is destroyed. Reconstruction is also carried out in the case when it becomes necessary to equip a superstructure on the house, and the existing foundation is not designed for an increase in load.

How to independently repair the foundation of a wooden house

When building wooden houses, several types of foundations are used, so we will choose the most common cases and consider the most effective and popular methods of restoration.

Repair of strip foundations

Small single cracks that appeared due to sedimentary changes in the soil under the house can be repaired with mortar (provided that the process has stopped and the foundation of the building has found new anchor points). To do this, the foundation is dug in to the entire depth of the spread of defects, the cracks are cleaned and filled with a sand-cement mixture.

Strip foundation is often used in the construction of wooden houses

Serious damage requires thorough restoration work. Most often, a new reinforced concrete structure is erected next to the old foundation tape, which is combined with the existing foundation with the help of bars and rods. Due to the fact that the repair structure is settled on a stable cushion, as well as due to the redistribution of the load over a large area, it is possible to completely stop the deformation processes and return the foundation to its former solidity.

Shtraba (colloquial shtroba) is a recess, groove or groove in a monolithic concrete base, which is intended for laying cables and other engineering communications, as well as embedding reinforcement elements in order to strengthen or combine reinforced concrete structures.

Repair of a uniformly sagging strip foundation

In the event that the subsidence of the house occurs evenly around the entire perimeter, the work to strengthen the strip foundation is performed in the following order:

A trench is being dug along the perimeter of the building, which will bare the old foundation to its full depth. The width of the pit is chosen so that it is convenient to work. In addition, it is imperative to take into account the increase in the thickness of the foundation during restoration activities.
If the subsidence is caused by miscalculations in the design or mistakes made during the construction of the foundation, then the supporting structure is built taking into account previous errors. Perhaps the building began to sag due to the high level of groundwater, which was not taken into account at the stage of its laying. In this case, the bottom of the repair trench should be below the freezing point of the soil.
Thoroughly clean the concrete surface from soil residues. Remove crumbling fragments of brick or rubble masonry.
The bottom of the pit is carefully rammed and covered with a layer of crushed stone 10–15 cm thick.
Holes are drilled in the old foundation for the installation of rods. It is best if the reinforcement enters the holes made with a slight interference.
Strip foundation repair technology
Individual boreholes (in a checkerboard pattern) are chiseled to widen their inlet to a diameter of 100 mm to a depth of 100–150 mm. In the process of pouring the foundation, concrete will fill these voids, combining both structures into one.
Create a reinforcement belt. To do this, the driven rods are welded to the volumetric reinforcing mesh.
To strengthen the reinforced concrete base, it is best to use not welding, but connecting the bars with a knitting wire. Such fastening is much easier and faster to make, and its elasticity will avoid damage and displacement of the armored belt during concrete pouring.
Formwork is arranged along the outer contour of the trench, for which any suitable lumber is used - boards, bars, wooden shields, etc. Before concrete is poured, the walls of the structure are covered with plastic wrap.
It is best to pour concrete gradually - in sections 1.5–2 m long. This will allow the solution to better penetrate into the grooves and fill all the voids and defective places in the old foundation. For this, a shield is made, which is installed across the formwork.
After filling the structure and setting the concrete, the wooden structure is removed and the foundation is waterproofed.
The remaining space is filled with soil. Of course, the earth should be poured gradually, adding a new portion of the soil only after the previous layer has been carefully compacted.
The repaired foundation will extend the operation of the old wooden house

To divert water from the foundation, a concrete blind area is made around the house. If the site suffers from excessive moisture, then the base of the building is protected with drainage, which can be equipped in parallel with the repair work.

Repair of individual sections of the foundation tape

If individual corners or small sections of the foundation are damaged, then spot repairs can be dispensed with. It is performed in the following sequence:

If an inspection of the base reveals its weakening along the entire perimeter, then the structure can be strengthened using a narrow (15–20 cm) encircling reinforced concrete clip. It is concreted using an anchor ligament with the foundation, using reinforcement and formwork.

Do-it-yourself replacement of the old foundation

If the foundation is destroyed or subsided so much that it cannot cope with the functions assigned to it, then it is completely replaced. The log house is not so heavy, so it is quite possible to do without a truck crane. To raise the walls to the desired height, hydraulic jacks with a force of 5–10 tons and props from logs or metal structures are used.

To avoid mistakes during the repair, the work is carried out in stages.

Determine the weight of the building. To do this, the total cubic capacity of the log house is multiplied by the specific density of the wood from which the house is built. Based on the calculations, they decide which lifting mechanisms will be needed and determine their number.
You can raise a small, light house without jacks at all, if you use a vaga - a long pole with a section of at least 80x80 mm. One of its edges is brought under the corner of the building and rested on a round deck, and the other is used as a lever.
To reduce pressure on the foundation, bulky things and equipment are taken out of the house. In some cases, they even dismantle the floor and stoves. Naturally, if the heaters are installed on separate bases, then there is no need to disassemble them.
With the help of wooden beams and boards, window and door openings are carefully strengthened. This will prevent distortion during the lifting of the building.
A wide trench is being dug around the perimeter of the house. It will provide access to the foundation and provide convenience when replacing it.
The old rubble or brickwork of the base is dismantled in small sections 0.3–0.5 m long - jacks will be installed in these openings. For small houses, it is enough to place lifting mechanisms only in the corners, while massive buildings will require additional supports in the middle of each wall.
To distribute the load on the jacks, you can use a powerful corner or channel
Install jacks. To prevent subsidence of load-lifting mechanisms, they must be based on a solid, reliable foundation. Thick steel plates or pieces of springs from a heavy vehicle, which are placed under the lower crown, will help to avoid damage to the log house.
Slowly and carefully raise the house. It is important that all corners rise as evenly as possible. To protect yourself in case of insufficient carrying capacity of the jacks or their displacement, wooden wedges are inserted between the lower rims and the foundation cushion. Spacers should be increased every 15–20 mm.
When lifting a wooden house, the main effort falls on the lower crowns. To prevent their sagging, the logs are pulled together with a steel hoop or strengthened with boards and bars.
Next to the jacks, as well as in other accessible places, temporary supports from a channel or powerful steel corners are placed under the log house - they will help unload the old foundation.
Any suitable materials can be used as temporary, safety supports.
The house is lowered, after which they begin to dismantle the damaged foundation. At the same time, it is not worth saving and dismantling only damaged areas - partial replacement will not significantly reduce the cost of repairs, as it will weaken the new foundation.
Dismantling the old strip base
Having reached the ground, they excavate it to a depth of 15–20 cm and equip a sand and gravel layer. The pillow is carefully shed with water and compacted.
Construct corner and intermediate supports. They can be metal, reinforced concrete, stone or brick columns.
Mount reinforcement and equip formwork. The wooden structure is made in such a way that it can combine the reinforced concrete base with the previously installed columns. To avoid leakage of the solution, the inside of the formwork is covered with plastic wrap.
The formwork for the new strip foundation is arranged in accordance with all the rules - with reinforcement and protection against leakage of cement laitance
Concrete is poured into the mold. The solution is compacted by bayonet, using a vibrating screed or manual rammer.
After the concrete has completely set, the formwork is removed and the structure is left open for another one or two days for the mortar to dry completely.
Several layers of waterproofing are applied to the concrete surface, and the top of the foundation is covered with roofing material. This material will prevent the spread of moisture from the base to the lower crown.
The gap between the foundation and the side wall of the trench is covered with soil, which is carefully compacted.
Slowly and evenly lower the house onto the new foundation.
On a new foundation, a wooden house will stand for more than a dozen years.

After the completion of the repair work around the house, a blind area is equipped and the ground part of the foundation is clad.

Features of leveling a skewed base

If uneven shrinkage is observed, and the foundation tape has sagged and warped, then a jack or wag is also used to repair and level it. The first thing they do in this case is to determine whether the deformation processes have stopped or the subsidence of the foundation continues. For this, the already known beacon method is used. Based on the experiment, a decision is made on the method of repair:

with strengthening the foundation with the help of additional reinforced concrete tape;
building up the sagging part of the base to a new height.

In order to restore the straightness of the surface in the first case, a trench is dug on both sides of the sagging corner. Its length should be such as to cover areas where the upper part of the foundation deviates from the horizontal. After that, the building is raised to a height of 15-20 mm above its original position, after which a repair foundation is equipped next to the problem area.

You can level the foundation with brick or stone masonry.

Alignment "horizontally" is carried out using brickwork and is regulated by a layer of mortar, in which pieces of steel reinforcement, crushed stone, etc. are laid. The repair is completed with waterproofing work, after which the trench is covered and the house is lowered into place.

If the shrinkage processes have stopped, then there is no need to dig a pit. The building must be raised and the surface of the sagging section of the foundation "to zero" must be brought out. For alignment, use the method discussed above.

Repair of a columnar or pile foundation

Owners of wooden houses installed on a columnar foundation may eventually face certain problems:

the roll of individual pillars due to the heaving of the soil, and, as a result, the slope of the building towards the defective columns;
subsidence of the supports, which led to the warping of the walls or the excessively close location of the lower rims to the soil.

Such problems require strengthening the foundation with the replacement of individual supports. One of the most effective and at the same time simple ways is the installation of bored piles.

Foundation repair scheme using bored piles

The house is raised according to the method described above (to restore the strip foundation) and firmly fixed in order to unload the support columns. The defective pole is dug in and removed. After that, the pit is expanded to dimensions of 400x400 mm (for columns with a diameter of 200 mm), deepened 0.3–0.5 m below the base of the old support and prepared for the installation of a new pile:

An undamaged skewed column can be straightened. To do this, from the side opposite to the direction of the slope, a tunnel is made, the pile is installed vertically, and the space around it is poured with concrete.

What can be done to avoid damage in the future

The reliability and durability of the foundation depend not only on its design and compliance with climatic conditions and soil characteristics, but also on competent hydro and thermal insulation.

Most of the problems associated with the subsidence of the base are errors associated with the choice of the depth of its underground part. Foundations, in which the sole is below the freezing level of the soil, require restoration or restoration work much less often than shallow ones. At the same time, certain types of soils (for example, peat) require reclamation measures or excavation of an unsuitable earthen base with subsequent replacement with imported soil.

An important detail on which the safety of the foundation depends is competent waterproofing. Since the foundation is affected not only by moist soil, but also by atmospheric influences, the hydroprotection system should be provided by:

wide blind area;
vertical and horizontal waterproofing;
effective drainage.

For wooden houses without basements, only one horizontal protection against moisture penetrating into the wood will suffice.

High-quality waterproofing will protect the foundation from the damaging effects of moisture

For this purpose, Bicroelast, Aquaizol, Bipol and other roll materials are used, which are laid between the foundation and the lower crowns. Waterproofing is laid in 2-3 layers along the edge of the foundation.

Vertical waterproofing prevents dampness from penetrating into the basement of a wooden house. It is applied both on the outer surface of the foundation, and on both sides. In this case, insulation work is carried out in several ways:

installation of roll or film materials on a layer of mastic;
coating the surface with a bitumen-rubber or bitumen-polymer mixture;
installation of geotextile membranes or arrangement of watertight locks using concrete clay panels;
applying penetrating cement-polymer compounds.

Special attention is paid to the drainage system - it should provide water drainage no closer than 2–3 m from the extreme point of the foundation.

If the walls of the basement suffer from excessive moisture and fungi, then in addition to waterproofing, the base of the building is also insulated. For this, special waterproof plates are used, which are glued to a layer of bituminous mastic, followed by sealing with plastic protective materials.

When choosing adhesive compositions for the installation of thermal insulation boards, it is necessary to ensure that they do not include acetone and other chemical solvents.

Video: how to repair the foundation of a wooden house

In conclusion, I would like to remind you that the work associated with strengthening and replacing the foundation is particularly complex and risky. At all stages of construction, you must follow the safety rules and adhere to the repair technology. Only in this case, you can count on the fact that the restoration measures will take place without unpleasant excesses and give the wooden house a new life.

When such “bells” occur, urgent action is required. Replacing the foundation is the most rational method, but it is important to pay attention to the following aspects:

when doing the work yourself, you will need specialized tools, you should take care of this in advance to find a complete set;
after the old foundation is dismantled, you need to install a more reliable foundation of a different type (this is a difficult job, so the help of professionals may be required);
it is worth making sure that the house itself will still serve for a long time.

What does strength depend on?

Foundation replacement may be necessary due to erosion of the soil due to rising groundwater or improper water drainage.

Reducing the strength of the base material is another negative factor. This is possible due to incorrect determination of the freezing depth, inappropriate use of low quality materials.

Base selection

The column base is used for medium-sized houses. Despite its apparent simplicity, it has gained popularity due to its reliability. The design consists of several pillars installed at the junctions of the walls - these are areas with maximum load. Pillars are made of stone, concrete or brick. It is worth noting the need for a mandatory step of 1-2 meters. The pile bored basis also refers to the foundation of a columnar type. It got its name from being used as load-bearing elements and filled with a specialized mixture. Soil with elevated water levels is the best place for such a foundation.

Base subsidence

Equipment

Replacing the foundation under a wooden house means freeing it from heavy objects and furniture. Next, the coating is removed and the floor itself is disassembled.