The foundation under the house is crumbling, how to properly strengthen it. Strengthening the foundation of a private house - how to do it yourself? Preparatory work before strengthening the foundation

The house, unfortunately, is aging faster than we would like. And if you feel that the floors have begun to sag under your steps, you notice that gaps have formed between the floor and the walls, and your wooden house has a slight distortion, then there are problems with the foundation.

An example of strengthening an old foundation

This indicates the need to repair the foundation of the house. And it’s better not to delay this. Here we will look at how to strengthen the foundation of an old wooden house with your own hands.

Studying foundation problems

Before starting repairs, it is necessary to carry out a simple analysis of the condition of the foundation of the old house, the results of which will allow you to decide on the method of restoring it. To do this, a ditch is dug along the entire foundation strip.

The ditch should have a width of 70-90 cm and be located as close as possible to the base of the house so that it is possible to expose all defects in the old foundation.

After this, it is necessary to carefully study the condition of the foundation, paying attention to the following characteristics: the material from which the foundation is made, the technology for constructing the foundation, as well as the quantity and quality of damage to the foundation.

Repair of a foundation made of rubble mixture

If an analysis of the condition of the old foundation has shown that the foundation of your house is made of rubble mixture and is in satisfactory condition (damage and destruction are spotty), then pouring the foundation is the right solution to your problem. Strengthening the foundation using this method is quite easy and affordable. And although this method of restoring the foundation of a house is not the most reliable, it can be easily done with your own hands.

This method consists of several stages:

1. The old base is cleaned using a metal brush or grinder with a special attachment.
2. Reinforcement of the old foundation is carried out, for which reinforcing bars are driven into it very carefully so as not to completely destroy the old foundation.

An example of reinforcement of a destroyed foundation

• Problematic fragments of the destroyed foundation are removed from the general foundation strip.
• The foundation is filled with a thin mixture of concrete. The mixture is not poured all at once, but in portions. This will enable the concrete mixture to saturate all the voids of the old foundation, strengthen it and make it monolithic. To prevent the mixture from being absorbed into the surrounding soil, formwork and transverse partitions are made.

Let us repeat that this type of foundation restoration is not the most reliable, and therefore, to achieve the strength of the foundation of your house, you should use one of the methods described below.

Brick foundation repair

In the case where an analysis of the existing foundation has shown that it is made entirely or partially of brick, then you can use the method of restoring the old foundation, which is based on the principle of expanding the old foundation by creating an additional reinforced concrete belt.

However, this method should not be used if there is a clear distortion of the building.

The process of restoring an old foundation by creating an additional belt has a number of features:

An additional foundation belt poured in this way makes the old foundation stronger and more reliable. This occurs due to its expansion, as well as due to the connection of the old foundation through anchors with a reinforced concrete belt.

However, we note once again that it will not be possible to strengthen the old foundation using this method if the house has obvious distortions.

Complete foundation replacement

If you find that your house is leaning, then be prepared for a more complex and time-consuming process of restoring the old foundation - completely replacing it.

Before strengthening the foundation, determine the reasons that caused these problems. Most often, it deteriorates under the influence of groundwater or due to soil subsidence. In any case, it is necessary to take these reasons into account and further protect the foundation of your home from their influence.

If the cause of destruction was groundwater, it is necessary to pour the foundation at higher ground levels and ensure a good waterproofing layer in it. If the cause of destruction is subsidence of the soil, then it is necessary to strengthen the soil by any available method.

So, first you need to raise the house above the old foundation. This can be done using special equipment, or you can do it yourself.

Scheme for strengthening the old foundation

To do this, you will need a five-ton construction jack. Jacks are installed at the corners of the building on some flat foundations, which will prevent the jacks from being pressed into the soil.

The jacks are raised one by one to a height of 1.5 - 2 cm. Do not raise the corners sharply (more than 2 cm at a time).

This can lead to the destruction of the structure of the house. The building must be raised smoothly, without additional distortions, which will preserve its integrity. However, in the process of raising the entire house, it is necessary to monitor the condition of the middle walls of the house. It is best to place metal supports under them after partially raising the house.

Upon completion of raising the house to the required height, the corners of the building must be secured in this position. To do this, you can use metal channels or ordinary wooden beams. The main thing you should pay attention to when selecting channels is their reliability and strength.

An example of raising an old house to install a new foundation

As a result of all these manipulations, the house appears to be floating above its old foundation.

We consider the condition of the foundation. If the percentage of violations of the integrity of the foundation is more than 50%, then such a foundation requires its complete replacement.

This is done by hand as follows:

If, in the presence of subsidence, you are still not ready to change the foundation completely, then you can resort to installing an additional reinforced concrete belt, connecting it to the old foundation using anchors. But this measure will only temporarily solve the problem of the destruction of the foundation of the house.

Repair of piled wooden foundation

This repair is carried out in cases where the foundation of the house is so-called “chairs”, or in other words log piles.

Complete replacement of a wooden pile foundation

No matter how wooden supports are processed, sooner or later they begin to rot and collapse under the influence of moisture.

In this case, there are several options for repairing the foundation yourself:

• replacing piles with the same wooden supports;
• replacing rotten wooden supports with stone, brick or reinforced concrete ones;
• replacing a columnar foundation with a strip foundation.

The work of repairing a pile foundation can be divided into several main stages. Let's look at each of them in more detail.

Stage 1 - Dismantling the base and cleaning the old foundation

At this stage, part of the base is dismantled so as to provide free access to the foundation.
For the same purpose, the base is freed from joists, boards, etc.

Stage 2 - Installation of temporary support

Installation of the temporary support is carried out at a distance of 50-110 cm from the old rotted base. They install a temporary structure under the lower crown of the house on both sides of the chair.

Using jacks, it is necessary to lift the house above the collapsed foundation. And again, we draw attention to the fact that this must be done very carefully, alternately lifting each corner of the house by no more than 1.5-2 cm at a time. Upon completion of this stage, it is necessary to place temporary supports under the lower crowns of the house, wedging them.

Stage 3 - Replacing the old chair with a new one

Now they are dismantling the old supports and installing new chairs in their place. In this case, it is necessary to ensure that the new supports fit neatly into the grooves of the old chair. At this stage, some problems may arise. Let's look at them in more detail.

1. The integrity of the plastering is likely to be compromised: cracks may appear and even layers of plaster on the walls may peel off. This is a minor problem that can easily be solved once the house is installed on a new stable and strong foundation.
2. There may be distortions in the internal openings of doors and windows. This problem can be avoided by installing stronger reinforced concrete or stone pillars instead of wooden supports.

We examined an algorithm for do-it-yourself repair of a columnar foundation involving the replacement of old foundation pillars with new ones.

replacing old foundation pillars

If you decide to replace the old columnar foundation with a stronger and more reliable strip foundation, then you should adhere to the following algorithm of actions:

Please note that in the case where the old building stood on a foundation with a low level of depth, then after arranging the new foundation it is necessary to ensure good drainage and build a blind area.

Repairing the foundation of an old wooden house with your own hands - how to strengthen and strengthen it

How to strengthen and strengthen the foundation of an old wooden house. Do-it-yourself foundation repair and filling.

The owner of a private house always wonders how to strengthen the foundation. Should you entrust it to someone or try to do everything yourself? Let's look at the main stages and weigh the forces.

You will have to correct the negative consequences of external factors on the foundation under the house, but what if you have never had to do foundation repairs yourself in your life? To understand which strengthening of the foundation of a building is preferable, you should understand the reason for its collapse. There are two explanations why pieces of the foundation suddenly begin to fall off and the foundation itself crumble: technology violations during construction or external negative factors (soil displacement, changes in its composition, groundwater movement, vibration).

Collapse of the foundation of the building

The first reason may include improper preparation of the binder mortar, poor-quality building materials, incorrect measurements, which led to misalignment of the masonry. The second “critical point” may be that during construction the composition of the soil, its moisture content were not taken into account, or the drainage was carried out incorrectly.

To determine whether the destruction of the foundation under the house continues and whether its strengthening needs to be organized urgently, paper tapes should be glued to the detected cracks. If they are not torn apart within a week, then the splits will not expand. You can use plaster tapes. In addition to visual inspection, soil samples are taken, including to determine its chemical composition. Thanks to this analysis, it is possible to select building materials that are not affected by external factors or their harmful effects are minimal.

Prevention of foundation construction

Like any structure, the foundation needs mandatory preventive procedures. Thanks to them, you can significantly extend the life of a private home and delay strengthening and putting it in proper order. It is recommended to pay attention to the following “pain points”:

• Before building a foundation, be sure to use geodetic and geological services, which will determine whether it is possible to build a residential building on a certain plot of land.
• In no case do not deviate from the requirements of technology: do not use a binding solution that does not correspond to the design, bricks with other hygroscopic properties, and do not skimp on the components of the concrete mixture.
• Do not make changes to the plan of a private house (reconstruction of load-bearing partitions and walls, construction of additional floors and extensions), which may change the application of support points to the foundation and redistribute the weight load of the main building.
• You should not neglect the construction of a shock-absorbing cushion under the foundation, drainage ditches and moisture insulation. For long-term operation of the building, you should not skimp on this work.
• All communications should be laid before the foundation is erected. The deployment of these measures after construction can lead to improper shrinkage of the entire building, and as a result, to the appearance of cracks and destruction of its foundation.

Let's start with the most popular, one might say, classic way of strengthening the foundation. The algorithm of actions has already been worked out for centuries, and therefore is most preferable because of its effectiveness and efficiency, and can be completely implemented with your own hands. The point is to build a new foundation, which is laid out around the house along its perimeter and serves as additional support for laying the old foundation. All work is divided into a number of successive stages.

First, square holes must be dug at each corner of the building in order to expose the masonry of the old foundation. The parameters of the pit are 1x1 m. The depth must be 0.5 m below the old base. Then you will need to make frames from reinforcement according to the number of corners of the building or along the length of the walls, if you decide to reinforce the entire perimeter. Then comes the installation of structures made of metal rods into the resulting recesses and the filling of square holes with reinforcement with concrete, the grade of which guarantees the special strength of the material.

Strengthening the foundation with a structure made of metal rods

The work is quite scrupulous - exposing the old foundation for too long can lead to negative effects of the external environment and subsequent distortion. That is why it is recommended to divide the pouring perimeter into sections not exceeding a length of 2 m. The next sector will be strengthened after the concrete in the previous one has “set” completely. For the same reason, it is recommended to expose the corner parts of the foundation as it is poured, so that the exposure time is minimal.

Strengthening the foundation of a wooden house

If the first method can be done with your own hands even by a single person, then for a wooden house it is a little more difficult to organize the strengthening of the foundation. The fact is that the most common problem with such buildings is rotting of the crown, that is, decay of the lower logs of the log house. For everything to go well, it is necessary to replace this part of the hut; at the same time, you can use the opportunity to lay waterproofing material.

How to strengthen the foundation of a wooden private house with your own hands - step-by-step diagram

Step 1: Disassemble the base

It should be noted that the operation to replace the crown should precede the strengthening of the base. First, a small dismantling of the foundation is done under the lower log in order to freely remove the rotten wood. At the junctions with other logs it is necessary to make cuts.

Step 2: Update the entire perimeter

Afterwards, part of the dismantled foundation is restored. When the entire procedure is done, the same is done on the opposite side of the house. Having finished with one row around the perimeter, you can begin replacing the next one. It should be noted that the crown of a wooden house is made up of two rows of logs, and when replaced, each one must be impregnated with special compounds and covered with a waterproofing agent.

Step 3: Unload the house

But what to do if not only the logs have failed, but also the old foundation has collapsed in several places, and serious work is needed to restore it? Here you can’t do without hydraulic devices. Remove the load on the foundation, i.e. remove heavy furniture and equipment from the room. It is also advisable to dismantle the doors and floor.

Step 4: Opening the Foundation

Along the entire perimeter of the building, every 2 m it is necessary to prepare holes into which channels or I-beams should be inserted; they will act as a platform. With the help of hydraulic jacks, these iron structures evenly lift the house to a height that allows strengthening the foundation itself. Temporary supports (welded structures or wooden blocks) are installed under the house. When full access to the foundation is obtained, reinforcement can be fully carried out. Having finished the work, you just need to put the house in place and bring in all the things.

But what about the types of the foundation itself, since most often it is columnar and strip? Will their strengthening take place in some specific way? Many people know that columnar is a system of piles (pillars) that are installed in areas of maximum load. To properly distribute the load on these supports, various devices such as grillages and strapping beams are used. The design of the tape is also intuitively clear from the name. This is a reinforced concrete structure in the form of a closed loop. Columnar is often combined with ribbon.

Reinforced strip foundation

If you want to deploy reinforcement to any of these designs, then both methods described above will work for this. In addition, it can be improved by drilling holes in the posts and equipping them with reinforced rods. How to strengthen it, you can even choose from several options: by replacing parts with new ones (block), or by erecting formwork and pouring a layer of concrete (monolithic).

Before starting work to strengthen the old foundation, it is important to analyze the reasons that led to its destruction. Only after finding out all the circumstances can you expect a positive result from the repair work.

Analysis of the reasons leading to the destruction of the foundation

Foundation destruction

Changes in soil characteristics for the following reasons:

• increase in loads on the foundation due to the significant mass of the structure. Their increase, accordingly, leads to an increase in pressure on the ground;
• improperly organized drainage or raising the groundwater horizon. Water, acting on the soil, leads to its erosion;
• the proximity of other structures, as well as the construction of extensions to the house, lead to an increase in loads on the ground. In this case, the soil located under the foundation is squeezed out;
• seismic impact.

Deterioration in the strength characteristics of the foundation material associated with errors made during the design, namely:

Types of foundation deformation

In addition to finding out the reasons that led to the destruction of the foundation, it is necessary to give an adequate assessment of its extent. This will allow us to determine the possibility of strengthening the foundation and the feasibility of this event. Maintainability is determined in accordance with the following criteria:

1. Damage is minor

This includes violating the integrity of the foundation finishing. The presence of phenomena of this kind does not affect the strength of the foundation and does not reduce its bearing capacity. Eliminating them is easy.

2. The damage is moderate

The occurrence of cracks is associated with the process of subsidence or destruction of the base. Before starting work, it is necessary to differentiate the nature of the cracks. Their horizontal arrangement poses less danger than their vertical or zigzag arrangement. In addition, it is important to find out what the nature of the process of foundation subsidence is. That is, this phenomenon is temporary or progressive.

Average damage

To clarify this circumstance, beacons are used. Plain paper can be used as them, but there is a risk of it getting wet. The use of plaster plasters is recommended. The simplest method involves applying a small amount of putty to the surface. Then, using a spatula, a mark is made in the form of a straight line. Even a slight shift of the tested surface will be noticed. In addition, when using this method, you can find out at what speed the destruction process occurs.

Temporary subsidence will not be detected by beacons. In this case, most likely, some shift of the soil located under the foundation occurred, it was fixed in a certain position and the likelihood of further movement is low. Therefore, to eliminate defects, it is sufficient to carry out routine repairs.

When lighthouses are destroyed, it can be argued that the destruction process is progressing. Sealing cracks will not give the required effect, since the deformation is close to catastrophic.

3. The damage is catastrophic.

The presence of defects of this kind can cause destruction of the structure. Timely work to strengthen the foundation will prevent extremely negative consequences from occurring. However, in practice there are situations in which this opportunity is missed.

The choice of technology depends on the type of foundation. In this case, each specific case considers its strengthening or replacement.

4. It is not possible to eliminate deformations

The condition of the foundation is so poor that repairs are impractical. In such situations, the most correct solution is to demolish the building. From an economic point of view, dismantling a house is much cheaper and simpler than measures to strengthen the foundation. The construction of a new cottage on the site of the previous one in accordance with building codes and regulations will allow you to have comfortable and safe housing.

Sometimes the only right solution is to demolish the building

Preventive measures: strengthening the foundation or eliminating the causes?

There is only one way to prevent foundation damage. Strict adherence to certain rules at all stages of its construction:

• Violation of technology during the construction of the foundation is not allowed. The concrete must be freshly prepared, and its grade must correspond to the design grade. There is a significant difference in the load-bearing capacity and hydrophobicity of different brands of this material. Unreasonable savings on materials during foundation construction can cause catastrophic consequences.
• Drainage and waterproofing are required. The cost of constructing a foundation is not comparable with the costs of carrying out these activities; the absence of a cushion and protection from moisture will lead to a sharp reduction in the service life of the foundation.
• In order to save money, you should not neglect carrying out qualified geological surveys. Information about the structure of the soil, the occurrence of groundwater and the depth of freezing, as well as recommendations for arranging the foundation, received from a competent specialist, cost significantly less than strengthening a cheap house foundation.
• The installation of communications should be carried out before the foundation is poured or laid. Carrying out excavation work can negatively affect the condition of the foundation.
• The design load must correspond to that provided for by the project. Rebuilding a house with an increase in number of floors or replacing finishing materials can lead to destruction of the foundation due to exceeding the permissible loads. To avoid such consequences of making an erroneous decision, it is necessary to consult an architect.

Ways to strengthen the foundation of a house

Builders have a wide range of tools and methods to strengthen the foundation of an old house. At the same time, time-tested methods do not lose their relevance. To choose the most optimal one, it is necessary to understand the advantages and disadvantages of each of them in relation to a specific case.

Ways to strengthen the foundation

Strengthening the strip foundation

The foundation of most private houses is. The characteristics of such foundations have the technical possibility of locally exceeding the normative loads. This type of foundation may experience local soil heaving. All types of foundations are built on bedded stone. When it draws down, it is important to stop this process in a timely manner.

Strengthening strip foundations

To do this, a hole is dug at an angle of 35 degrees in close proximity to the foundation. Its depth should reach the level of laying the bed stone. Then a pipe with a diameter of 150-200 mm is placed in the resulting pit. With its help, a thin concrete solution is poured, which is continued until the soil is completely saturated with it. At this stage, it is necessary to suspend all work for a couple of hours. At this time, observation should be made of the behavior of the soil in terms of saturation with the solution.

If the solution leaves, then continue filling the hole after a few days.

As practice shows, to completely saturate the soil, the procedure must be repeated two or three times. Control over the situation is carried out by beacons. In case of a slight change in their position, they move on to the next stage.

A ditch with a width of 200-350 mm is dug along the contour of the foundation. At its bottom and on the outside, a structure similar to formwork is constructed from boards. Pins are driven into the foundation, and a reinforcing mesh is attached to them. The resulting reinforcement is filled with concrete mortar filled with fine gravel and crushed stone. Such a structure will make it possible to significantly strengthen this corner of the house and evenly distribute the loads in the horizontal plane, which will stop the process of subsidence of the house.

Restoration of a foundation with cracks

Crack formation in the base and distortion of load-bearing structures can be of a different nature. Therefore, the first priority is to find out the nature of the processes taking place in order to find an adequate way to strengthen the foundation of the house.

Restoration of a foundation with cracks

If there is destruction along the perimeter of the foundation due to increased loads or exposure to moisture, a trench is dug that follows its contours. After this, the surface is thoroughly cleaned to remove the layer of plaster and adhering dirt. Next, the metal mesh is fixed with anchors driven into the base. Finally, the concrete solution is poured layer-by-layer with careful compaction.

If the foundation material is rubble stone, a monolithic slab of concrete or combinations of concrete-based materials, then a widened reinforced concrete frame is used. In this case, it is necessary to carry out reliable fixation, using through anchoring, with the old masonry material. The idea of ​​​​building such a structure is that the old and new foundations work as a single whole.

In some cases, there is a need to strengthen areas where the foundation is weakened. For this purpose, a new foundation is created locally. Its task is to redistribute loads and partially unload the old foundation.

Partial foundation replacement

If the foundation fails completely, it becomes necessary to replace it. To accomplish this task, it is completely unloaded, and at the same time the stability of the structure is preserved.

Unloading

This activity can be accomplished by installing so-called chairs, which are made of wood. Their installation occurs perpendicular to the foundation tracks. To secure the building, pillars placed under the walls can be used. The use of braces to hold the base and transmit forces at an angle to the ground is not excluded.

Before starting repair and restoration work, beacons should be installed. This is necessary so that the likely deformation process during this work can be detected. After this, they begin directly to implement the planned activities, which begin with digging a pit. The foundation is laid in sections, the length of which should not exceed two meters.

During excavation work, walls must be reinforced with struts. Next, a dig is made under the foundation and the soil is removed. Then the formwork and base for the foundation being constructed are installed. The sole is cleaned and, where required, dismantled. The old and new masonry are fixed together using rigid cement mortar and crushed stone. Having completed the foundation in one place, it can be continued in another.

Very often, the desire to increase the living space of a house comes to naught due to insufficient foundation strength. Indeed, it is impossible to significantly increase the weight of a building without changing its foundation, because the old foundation may burst or shrink. All this, in turn, provokes the appearance of cracks on the walls of the house, and ultimately the complete destruction of the building. Also, microcracks often appear in the walls in old and new houses. The article will discuss methods of strengthening foundations.

Before starting work on strengthening the foundation and foundation, you should conduct a close analysis of the current state of the house, evaluate its capabilities, and only then begin work to strengthen it. Usually, professional workers with special equipment are invited to do this or the problem is ignored, but you can carry out the work yourself. Strengthening the foundation allows you to avoid its complete replacement, which usually costs home owners a tidy sum. In order to carry out all types of work efficiently, it is necessary to evaluate the factors influencing the deformation of the foundation of the house and reduce them to a minimum or completely eliminate them.

Determining the cause of partial destruction of the base

Initially, incorrect design of the foundation, possibly an erroneous calculation of the future load on it.

• Failure to comply with technology during foundation laying.
• Saving on building materials, using cement and other low-quality materials.
• Improper operation of the building (for example, lack of heating in winter).
• Poor quality waterproofing.
• Sloping terrain.
• Significant changes in important soil indicators that have occurred since the construction of the house. This is usually caused by an increased level of groundwater, oversaturation of the soil with water, and swelling of the soil.
• Large-scale excavation work carried out near the foundation (nearby construction, laying communications).

• Increased load on the foundation of the house due to reconstruction or redevelopment.
• Internal or external vibration (proximity to the railway, earthquakes, etc.).
• Flood or high water that caused sudden soil moisture.
• Soil freezing.

Changes in groundwater levels due to floods and prolonged rains can cause heaving. Because of this, the house seems to be squeezed out of the ground, which leads to the building being skewed. In this case, it pays to install a drainage system and waterproofing the base before strengthening the foundation, if they were not laid during construction. You should also carefully examine the land plot to identify different types of soil under the building. Depending on the result, a decision is made on how to properly strengthen the base with your own hands.

Inspection of the foundation to be strengthened

• External inspection will allow you to analyze the size of the building and the current condition of the load-bearing walls. It is also important to determine the load on the foundation, to detect all cracks and slopes that indicate problems with the foundation.

• Underground inspection must determine the design and dimensions of the foundation, what material was used when laying it, characteristics, strength, and depth.

There are also situations that require strengthening the foundation even in good condition:

• increased load on the foundation (case concerning expansion or construction of new floors);
• settlement of the house within limits above permissible standards;
• the appearance of any vibrations near the building (this applies to any construction work near the house).

Before you begin to strengthen the reinforced concrete base, you should determine whether its shrinkage has ended. This is a fairly long process, requiring months of observation. To do this, plaster beacons are installed across the detected cracks; if after a month there are no flaws on them, then you can safely begin strengthening.

Unloading the foundation

The final stage of preparation is unloading the base, which can be either partial or complete. This is an important stage to prevent distortions during strengthening work.

• You can partially unload the building by using supports and struts, which are made of both wood and metal. To begin with, support “pillows” are placed in the basement at a distance of two meters from the wall, a support beam is placed on them and the racks are secured, which then must be connected by a beam to the ceiling and wedges to the support beam.

• To completely unload the base, you will need to install metal beams. Under the bonded row of masonry walls, grooves are made on both sides, into which frame beams must be placed and bolted (20-25 mm) every two meters. The points where the beams are connected must be welded with overlays, and the distance from the wall to the beam must be filled with a solution of sand and cement. Drill holes from the bottom of the walls at a distance of two to three meters from each other, into which to insert beams. Place cross beams on support pads on both sides of the wall.

Ways to strengthen foundations

There are various methods of strengthening the base:

• piles;
• reinforced concrete jacket;
• cementation;
• increase in sole;
• low tides;
• laying new foundations;
• clips;
• shotcrete.

Foundation strengthening structures

Strengthening the foundation with piles

• Micropiles with a diameter of 150-300 mm very convenient to use due to the ability to combine drilling with injection of solution into wells. In this method, you can use drill rods that remain inside the pile and provide more reliable reinforcement.
• Bored piles installed by drilling wells along the entire length of the foundation, both outside and inside the building using drilling equipment. Wells must be made every one and a half meters with a depth of approximately 2 m. A reinforcement pin must be inserted into them and filled with concrete mortar, after which the structure must be attached to the foundation with anchors.

• Indentation piles used if it is necessary to transfer the load to deep-lying hard soils, special equipment is used for this. To ensure a good connection between the base and the piles, beams are installed at the base.
• When the groundwater level is high, use external piles, onto which the base is placed, passing a reinforced concrete beam through it, it is a kind of connecting link.
• Metal tubular piles are crushed immediately on both sides of the base by welding the sections using special equipment. For the same purposes, it is necessary to install a reinforced concrete frame connected to beams, which, in turn, are supported by jacks.

Technology of strengthening the foundation with a reinforced concrete jacket

• An easy-to-use method because all the work can easily be done by one person. To do this, you need reinforcement for tying the frame (16-18 mm) and M400 concrete.
• They start by digging the foundation so that each foundation is no more than three meters in length. First you need to dig out and strengthen the corners. The depth of the excavation should be 50 cm greater than the depth of the foundation.
• Then build a reinforcement frame, which, as it were, covers the underground part of the building from the outside. The maximum load of the frame is increased by attaching it to the existing foundation with anchors. Arrange the rods of the military belt vertically and horizontally, tie the intersecting points with wire.
• Then install removable formwork with supports and fill in the solution. This is exactly how a reinforced concrete frame is made, with the help of which you can qualitatively strengthen strip and column bases.

Strengthening the foundation of a house with cementation

• Cementation, or injection, is different in that it places hollow tubes in the foundation cavity. Typically this method is used for rubble bases, which have many voids. The accessibility of the method is achieved due to the fact that the cavities between the bricks and rubble are filled with mortar, and small cracks are covered up.
• Hollow tubes are placed in such a way that they extend beyond the holder by more than 40 cm, and be sure to fix them with a solution. To fill the cavity of the tubes, cement is poured into them, less thick than for the holder. The work must take place in a certain sequence: first you need to make a clip, after two days, when it hardens, fill the pre-installed tubes.

Cementation, like another method - relaying, is allowed only if the foundation has retained its load-bearing capacity.

Strengthening the foundation by widening the sole

This method is quite difficult to do on your own, but several people can do it.

• The sole is a cushion made of reinforced concrete that serves as a support for the base. First of all, you should mark the foundation every 2.5-3 meters, make excavations on the sides of the foundation and under it.
• Place a reinforcement screed under the base and fill it with a solution, which you should try to distribute as uniformly as possible and get rid of air bubbles. A concrete vibrator is useful for this. The side walls of the sole need to be raised to the base by a distance of 15 centimeters.

Strengthening the foundation with ebb tides

• This method of reinforcement is relevant for foundations made of brick or rubble.
• Reinforced concrete castings are used instead of a reinforcement cage. They should be installed on both sides and pressed so that their top does not touch the wall, and the bottom part - vice versa.
• Then secure the structure with jacks and a screed, dig trenches with grips up to two meters.
• Fill the distance between the wall and the ebbs with mortar.

Strengthening the base with clips

• Strengthening can be carried out with reinforced concrete clips (it is possible to use double-sided ones or use tubes that inject mortar). This method allows you to strengthen the foundation throughout its entire thickness, since the solution easily reaches all the voids of the masonry.

• First, a section of the existing foundation up to three meters in length is excavated. It should go half a meter deep and its width should be one meter.
• Drill holes through on both sides, arranging them like chess. Place reinforcing rods in them (14-20 millimeters), to which a frame with cells of 150 by 150 millimeters is attached. Then install the formwork and fill the resulting space with concrete.

Strengthening the foundation with shotcrete

• This method is best left to professionals, as it requires the use of a concrete cannon. You need to dig a one and a half meter trench around the base, clean the masonry and apply additional notches.
• The excavated and cleaned parts are covered under pressure with a solution using a gun. This will completely fill all the cracks.
• This strengthening method should be chosen when the foundation is not severely deformed or before the construction of new floors of the house in order to reduce the load on the foundation.

Strip foundation strengthening technology

• A trench is dug along the entire perimeter of the base. The width must be made so that all work is carried out in comfortable conditions and taking into account the increase in the thickness of the foundation.
• Clean the surface from dirt.
• Install fittings.
• Form a reinforced belt. This can be done by welding the reinforcement in some places, as well as tying it with wire.
• Put together the formwork.
• Pour concrete.
• Make waterproofing.

Strengthening the foundation: step-by-step instructions, Construction portal

Construction of houses Very often the desire to increase the living space of a house comes to naught due to insufficient strength of the foundation. Indeed, it is impossible to significantly increase weight

Very often, owners of country houses are interested in strengthening the foundation - no wonder, because everyone wants to be confident in the reliability and durability of their home. Carrying out work to strengthen foundations is a whole story, the outcome of which depends on theoretical knowledge and practical experience. But don’t be afraid, strengthening the foundation of a private house can be done with your own hands, of course, if you are not faced with a situation where it is easier to build a new house than to repair an old one.

Strengthen the foundation or eliminate the cause

The conclusion that suggests itself: first eliminate the reasons that cause changes in the foundation (its destruction) and natural violations of the integrity of the house built on it. Let's look at the most common reasons:

• the foundation was initially built in violation of technology. In this case, it is definitely necessary to strengthen it;
• changes in the foundation of the house are associated with increased soil moisture. In this situation, much attention is paid to the blind area of ​​the foundation; if necessary, drainage of the foundation is arranged. We will talk about the latter solution in one of the following articles;
• The site chosen for construction has a heterogeneous soil composition, which leads to local deformations of the foundation of the house. As an effective solution, a set of measures is used, including strengthening and insulating the foundation, drainage, and, if possible, replacing part of the unstable soil with crushed stone and sand.

To summarize the above: first, you should take care of additional thermal insulation of the soil layers located under the foundation and next to it (this measure will reduce heaving phenomena, if such are typical for your site), and also ensure minimal humidity of the site near the base by developing a drainage system. Only after this can you think about serious work to strengthen the foundation.

Ways to strengthen the foundation of a house

Let's start with the fact that the house can be stone (made of bricks, blocks, etc.) or wooden. In one of the previous articles, we talked in some detail about repairing and strengthening an old wooden house, for example, you can familiarize yourself with some useful solutions. If with wooden buildings everything is simple - they can be “raised” if desired (what can I say, even replacing the foundation under a wooden house is quite possible), then with stone houses things are somewhat different: they are heavy, and in order to change their position, you will have to spend a lot of time and money. Therefore, the approach here is different.

Most stone houses are built on a strip or slab foundation. In the latter case, problems with the foundation are extremely rare, so we will only consider strengthening the monolithic tape.

Strengthening the MLF

Strengthening the strip foundation buried below the GPG

As a rule, a monolithic strip base, the base of which is below the soil freezing depth (SFD), is not subject to uneven lifting influences from the soil. Otherwise, work to strengthen it is carried out in the same way as described above.

In some cases, problems with such foundations are caused by the action of groundwater, which literally washes away the soil from under the foundation. The same can be said for the monolith itself, which, under the influence of high humidity, loses its strength characteristics. The only feasible solution in such situations is to arrange a drainage system for the foundation. If the buried foundation is badly damaged and the concrete begins to crumble, then the upper damaged layers should be removed, treated with cement laitance and then thoroughly waterproofed. In case of significant damage, the tape must be expanded by installing additional reinforcing elements, as described above.

Finally

If your foundation for a one-story house does not show any signs of weakness or you notice cracks in it that do not increase in size over time, then it is better to avoid strengthening the foundation (only cement the cracks) - an illiterate approach can only aggravate the situation.