In case of significant destruction of the foundation, while eliminating the destructive factors, the foundation is also repaired.
The liner is carried out with the help of grips in separate sections with a length of one and a half to two meters, which depends on the depth of the foundation strength. When deeply laid, the grips are reinforced with uprights and beams.
The formwork is removed at the end of concreting. Metal fasteners are left in the concrete.
This method is advised to be used with a large volume of structures to be strengthened, a shallow depth of foundation, a deep finding of groundwater.
It is important to comply with the technology of work to prevent the resumption of the destruction of the foundation.
The clips are side attachments made of concrete blocks, connected to the old masonry.
The most preferred are two-leg, torque-free ferrules.
This method allows not only to strengthen the foundation, but also part of the wall.
For strengthening by the broadening method, the foundation is marked out for grabs. The length of the marks is 2-3 meters.
Holes are punched in the plinth for transverse reinforcement. A longitudinal beam is placed between the plinth and the wall. Further, formwork is installed in the trench and poured with concrete.
In conclusion, I would like to say that foundation repair works are especially dangerous. This type of work must be performed with extreme caution, applying all safety measures and not endangering either your life or your assistants.
VIDEO
Repair of the basement is very necessary, because this is exactly the structural element of the house that protects the foundation from moisture and destruction. If there is no basement, or it will be in a destroyed state, the foundation and the lower part of the masonry will begin to collapse, which will affect not only the humidity inside the house, but also the quality of the walls, floors, and so on. In this case, cracks and serious chips, rotting of lags, gradual destruction of walls are possible.
Therefore, repairing the basement of a private house is very important. , and it is desirable to produce it exactly at the moment when its first defects were noticed. But if the base is in an unusable condition for several years, this is also not a problem, because we will restore it in a few days.
It is most correct to choose a warm and dry season for such work, preferably without serious heat. It may be the middle of summer, depending on the regions, but we suggest that you repair the basement already at the beginning of spring, as soon as it dries out after the snow in the fresh wind and the sunshine gaining temperature. For example, you can start the process in mid or late May so that you are not too hot to work and the temperature for finishing is acceptable.
It is simply impossible to carry out repairs in cold or rain, as well as in severe heat, because a stable temperature is required for high-quality adhesion of the solution to the basic materials and its uniform drying.
You will need to prepare the place of repair - beat off the peeled parts well, try to remove the debris, but do not wade deeper, knocking on and on with a hammer. After that, study the blind area, as it plays a significant role in protecting the foundation and the appearance of the building.
If the blind area is in order, it can be redecorated, but if there is practically no blind area, it will be necessary to fill in a new one.
The blind area can rise 4-7 cm above ground level, but it should go about 20-25 cm deep. You determine the width yourself, dig out a place to fill the blind area and clean the foundation of the house. It is important to remember here that the blind area should have a slope of several degrees from the house so that water does not stagnate under the house itself.
When the place is ready, you should attach as much as possible to the foundation, nail the reinforcement to it, to which the mesh is welded. You should not be especially zealous, but the foundation of the blind area must be done efficiently.
When the reinforcement for pouring is ready, it is necessary to fill in the gravel cushion, set the formwork along the height of pouring the blind area, and pour everything from above with cement mortar. But before this stage, you can also make waterproofing, which will be very appropriate. This can be the standard waterproofing of the basement of the house, or the classic, clay, when a layer of clay 15 cm wide is laid along the entire height of the blind area around the house and is well trampled.
If you want to get a stronger blind area, lay several layers of a thin mesh, and also make it on the basis of a solution with rubble.
The plinth is upholstered and cleaned, the blind area is flooded and fits snugly to it - it remains only to move on to our main task.
A fine reinforcing metal mesh should be filled around the entire perimeter of the base. It is advisable to give it a shape, since the mesh will be held by the layer of solution. That is, the mesh can be filled more evenly vertically by adjusting its position with dowels.
The next step is priming. You can apply the primer directly through the mesh so that the composition gets onto it and onto the surface itself. If no primer is intended, just moisten the surfaces well before applying the grout.
After that, with a more liquid solution, we throw a layer well on the mesh so that the plastering mixture penetrates through the mesh and fills all cavities along the base. To do this, you should not accelerate, it is necessary, on the contrary, to act very carefully, even pressing the solution into the mesh, clogging all cavities and hollows with it. Thus, finishing occurs around the entire perimeter, with a layer through which the mesh itself will only be visible.
It is advisable to let the layer dry a little, and then you can proceed to the final plastering. Here you can put another layer of cement mortar, or work with decorative plaster, original stone and brick laying.
Depending on your choice, there may be very different options for further processes.
The repair of the basement of a brick or panel house has been completed, and now we need to tidy up its exterior. There is already a blind area, but it also requires a base to match, which we will now draw up.
The base is ready, and now it is necessary to protect it from the harmful effects of atmospheric phenomena. This can be done with bitumen or other special mixtures, but you can always use the old-fashioned method.
You need to heat tar and diesel fuel over a fire in an old bucket. Heat slowly over low heat, making sure to protect yourself from possible injury. By stirring slowly, you will be able to prepare the quality coating solution that was previously used everywhere. It is necessary to use hot resin of the consistency of jelly using a large round brush, evenly applying the mixture to the base with a thick layer.
If you can spend more money, create a more interesting look and effective protection from the effects of moisture, wind, frost and sunlight, use modern finishes. Often, this is just a decorative plaster with protective properties or further painting, but often craftsmen make a stone base or a base from artificial stone, which is in no way inferior to natural finishing.
To lay the finishing material, you will need to choose the right adhesive mixture and study the instructions for using the materials, because many of them will need a primer, mesh, and maybe the preparation of a special layer.
At every stage of the repair and decoration of the basement of the house in the country it is worth remembering that this is often a very important structure, on which the durability of the building largely depends.
The basement has been repaired, and now we just have to pay more attention to the protection of the foundation from moisture, for example, just grease the cracks with resin, having previously repaired them with special mixtures, or by placing the material that was used for finishing in place of the defects.
Often, owners of private houses and cottages are faced with the problem of repairing the foundation. Cracks form on the walls of the building, on its plinth. They are small at first, but get bigger over time. They "say" that it's time to start repairs. Having at hand the necessary devices and tools, knowledge of how to repair the foundation of a house, you can easily cope with this task. The work itself, of course, is not easy, but we will try to make it as accessible as possible.
Below you will learn about the general principles of work, about the main difficulties and mistakes that are often made during repairs.
Causes of deformation of the foundation of the house
Flooding and loss of soil bearing capacity.
The reasons for the loss of bearing capacity should be divided into two main categories. As you know, the soil on which the foundation of the house is built is the first to lose its bearing capacity. This can happen due to erosion or flooding, due to which the soil becomes saturated with water and loses its bearing capacity.
This usually happens due to certain properties of some types of soil, which, when a certain level of moisture is reached, ceases to be a reliable base. It happens that the soils retain their strength well, but over time they are washed out from under the foundation structure, forming voids (most often this happens in areas where different types of sandy loam and sandy soils are found).
Basement subsidence often occurs in those places where marls and limestones are included in the soil, especially if the soil water, due to technological reasons, has acquired acidic properties, which is a powerful destructive factor for calcites.
Quite common causes of subsidence are "underworking", that is, the formation of underground voids as a result of subsidence. Side jobs are the result of oil production, mine workings, pumping out artesian water, etc.
Loss of the bearing capacity of the foundation.
Another category of reasons for the loss of deformation of the foundation structure is the loss of the bearing capacity of the structure and the need for urgent repairs, as a result of factors that negatively affect the foundation, causing its destruction. In the same way as in the case of the bearing capacity of the soil, groundwater can be one of such reasons.
Ordinary water can easily cause corrosion of the foundation material and lead to structural destruction, despite the preservation of the bearing capacity of the soil.
VIDEO But almost the most basic reason for the destruction of foundation structures is a violation of construction technology. For example, one of the most common violations is non-compliance with the requirements for the depth of the foundation. When it freezes to a depth of 1.1-1.3 m, the foundation must be deepened by 50-60 cm (one of the most common mistakes during the construction of country houses).
Often the reason can be hidden in the use of materials that cannot be used for the construction of foundations, but at the same time it turned out to be inexpensive to buy. For example, sand-lime bricks, slag concrete, etc.
Before you repair the foundation of a house, it is important to understand the nature of the destruction of your structure and the reason for this, you need to carry out a complex of research work.
Of course, a serious examination of the foundation structure without the presence of special devices and tools will definitely not work. On the other hand, it can be very expensive to pay for the services of specialists from a construction laboratory. Therefore, we recommend that you do all the work yourself, especially since it is not so difficult.
There are some inexpensive and simple tricks to help you figure out exactly what to do and if it's worth it at all. For example, it happens that the formation of cracks is a consequence of a process that began and ended quickly and is unlikely to be repeated in the future. For example, a snowy and frosty winter, which caused freezing of the structure under the foundation and, at the same time, an increased snow load. In this case, it is enough to confine ourselves to cosmetic repairs.
How to determine the crack opening movement
To track the deformation process, it is necessary to carry out the first type of research work, determining whether the cracks continue to grow and what is the nature and speed of this process. Therefore, as soon as you notice the formation of cracks, you need to install markers (beacons) on them.
Beacons in their simplest form are made from cement mortar, gypsum with the addition of sand or other similar material (for example, ready-made plaster mixture). At the same time, it is important that the material after solidification does not allow plastic deformation, that is, it is fragile, and the beacons themselves adhere to the surface of the basement (wall) of the building reliably.
After mixing a small composition, it is applied to the crack in such a way that the layer is not more than 3-5 mm. The size of the marker is approximately 10-12 cm in length and 3-5 cm in height, and the crack itself should be located approximately in the middle of the beacon.
At least 2 beacons are installed on each crack, one closer to the end of the opening, the second closer to the beginning. The beacon marker is made using a narrow spatula, cleaning the base for maximum quality adhesion to the surface.
Until the beacon has frozen, a thin horizontal line must be drawn on it (with the same spatula or metal ruler). Beacons must be numbered by squeezing out the number with a nail or a pointed stick on a marker. The date and number of the installation must be entered in the observation book.
If the crack widens, the beacon will crack. By measuring the width of the crack on the beacon at regular intervals and recording the date and measurement results, you can determine how quickly the deformation process goes, having an idea of its development.
Which part shrinks can be determined by analyzing the risks of displacement relative to each other. Either the crack remains without displacement of the building, or it simply opens up. Some types of precipitation, depending on the nature of the cracks, can be seen in our photos.
Digging pits
The next type of research work is more laborious, but it will provide more information. Near the foundations, you need to dig at least two pits. The pit is an ordinary pit about 1 meter long and up to the base of the foundation. As for the width, it should allow it to work normally, and the angle of the slope is done so that the earth does not collapse (for this purpose, it is better to strengthen the pit wall with boards).
Pits are dug in places with the most pronounced information. With its help, you will get access to the base of the foundation and the answer to such questions: what is the depth of the foundation, its materials and structure, in what condition it is, the state and presence of waterproofing, groundwater.
VIDEO The groundwater level can be determined exactly after 24 hours - by the height of filling the pit with them. Through tests for alkalinity and acidity, you can find out how aggressive these types of water are. Similar tests (litmus paper, etc.) can now be purchased in stores with agricultural chemicals.
As soon as all the above studies are completed and the causes of cracking are identified, they proceed to the next stage and repair the foundation.
Let's make a reservation right away, the possibility is not excluded that the deformation is serious, that it will not be possible to eliminate it on our own. For example, significant progressive flooding, extensive landslide. To eliminate the consequences of such factors, measures will be needed both in terms of characteristics and in terms of financial costs of the necessary special equipment, which go beyond the capabilities of even a well-to-do person. Fortunately, this problem is extremely rare.
The first group is worth considering. If you find flooding, drainage or drainage work will be required. It is possible that the flooding was caused by the flow of melt and rainwater under the foundations of the house. In this case, it is enough to install a wallpaper barrier, which will direct water around the house along special drainage grooves, as well as a high-quality blind area, at least 80 cm wide.
If for one reason or another there was an increase in the level of groundwater, then you simply cannot do without drainage. In general, drainage is a closed counter-trench around the problem area.Perforated pipes are laid in the trenches, which are subsequently covered with gravel. As a result, drainage collects excess water, which is discharged into storm sewers or elsewhere, dictated by technical conditions and relief.
VIDEO Now it is worth considering the case of repair on your own, when cracking is provoked by the laying of a structure above the level of soil freezing. This does not in all cases give significant deformation, everything directly depends on the level of heaving of the soil, namely, its ability to expand in case of freezing. However, over time, the properties of the soil may not change.
For example, due to saturation with water (leaky water supply system, collapsed blind area, etc.). And then the building, which stood for half a century, suddenly begins to crackle.
Foundation insulation methods
In this case, the insulation of the foundation will be a topical event. To do this, a trench is dug (along the basement and to the bottom of the sole of the structure), which is then filled up, but not with soil, but with fine gravel or coarse sand. Such soil will not expand even when frozen. On top of the backfill, it is necessary to arrange a layer of insulation, as well as a blind area.
Of course, backfill can be done with one insulation, but in this case it will cost much more. Before making the backfill, you need to worry about the implementation of waterproofing, if it is missing. It is advisable to insulate the lateral surface of the foundation.
Finally, the most time-consuming and difficult option is when you need to do a serious repair of the foundation with your own hands, since the structure is too destroyed.
Based on the research data, you must determine what combination of conditions caused the destruction and whether these negative factors continue to act now. If it makes sense to remove negative factors, but this is impossible for some reason (for example, groundwater has risen, and the arrangement of the drainage system is very expensive), it is necessary to neutralize them by using special materials, other constructive measures (use high-quality waterproofing, acid protection for acidic environments, etc.).
Errors when strengthening the foundation
Often, when strengthening the foundation, an unpleasant mistake occurs - amateur inexperienced craftsmen perform "strength", digging a trench along the structure with foundations. Next, holes are drilled for anchors or pieces of reinforcement are driven into the seams if the foundation consists of wild stone or individual small blocks.
Upon completion of these activities, the trench is poured with concrete. This is done with the hope that the structure, expanded in this way, will increase its bearing capacity. As a result, a concrete massif is obtained, which lies next to the house, like a semblance of a waste, and costs that are incommensurate with an insignificant effect.
VIDEO Supply of a new foundation
In order to rectify the situation, it is necessary to carry out more serious measures, to restore the destroyed structures, or even to bring a new foundation under the house.
For brick or houses of small masonry stones, reinforcement is made in individual areas. Digging is carried out already under the finished structures with further concreting. The length of such a section should in no case be more than 60-80 cm. When working on cracked sections, the digging is done three times less than the distance between the cracks. It is good if it is executed on both sides.
If the foundation of a wooden house is being repaired, it does not matter whether it is made of logs or from a bar, then the work is somewhat easier. First of all, reinforcement is made at the edges of the timber (log), then between these anchor points. The work can be performed quite calmly and the "grips" for repairs can be made much wider (up to 2 m), since the main weight of the structure will be borne by the lower crown.
Repairing the foundations of houses is a work with increased danger, so it is important to be as careful as possible and not take risks. It is not worth doing such work alone, there should be at least two people, and preferably three.
It is important to carefully consider the entire sequence of actions, do not rush and use safety devices (jacks, supports, etc.). Then the repair of the foundation will proceed safely, despite the fact that the repair of the foundation structure of a country house or a country cottage is being carried out.
Arrangement of the foundation is one of the most important stages in the construction of a structure of any size, weight, configuration and purpose. The supporting structure performs several main functions: it accepts and ensures an even distribution of the loads created by the structure erected on top of it, and also protects the building from forces and stresses arising in the soil.
The foundation perceives heavy loads, but sometimes it does not withstand them and collapses
Violation of the foundation construction technology in the future can turn into the most catastrophic consequences, up to the destruction of the building. Along with this, some problems that have arisen due to improper arrangement of the base can be corrected on their own, eliminating the risk of more serious damage. It is with information on repairing the foundation on your own that you are invited to familiarize yourself further.
DIY foundation repair
The list of reasons that can lead to deformation of the foundation is given in the table.
Table. Why is the foundation crumbling
Reducing the bearing capacity of the soil
The formation of voids in the soil
The presence of inclusions in the soil
Decrease in the bearing capacity of the support under the influence of groundwater
Violation of building technologies
Common foundation defects
The table provides a list of the most common defects in support foundations.
Table. Foundations defects
Destruction of the base of the log bath
Destruction of the foundation under atmospheric influences
Destruction of the foundation from FBS blocks
Cracks in a brick support
Pushing piles out of the ground
Deformations of the walls of the foundation
Layering of rubble masonry
Violation of the integrity of the side surfaces of the support base
Break of the supporting structure in height
Cracks in the slab part of the supporting structure
To determine the nature of damage, the causes of their occurrence, the possibility of self-elimination of defects and, in general, the need to perform any actions, it is necessary to perform a number of research activities.
Exploring the nature of destruction
The item on the need to take actions is included in the list for a reason. It is possible that the reasons that led to the occurrence of certain deformations of the supporting structure were of a single nature and will never appear again. For example, once every 100 years there was a very snowy and frosty winter, during which even the soil under the foundation was frozen. If such weather conditions are not typical for the area in which the building is located, all repairs can be reduced to one only elimination of cosmetic defects. But the diagnosis is carried out under any circumstances, because an outwardly insignificant problem can in fact be very serious and dangerous.
Determine if cracks are growing
The challenge boils down to the following: you need to understand whether the cracks continue to grow. If so, the nature of the process and the rate of its development are additionally established.
The study is carried out using special markers (beacons).
The easiest way to make a lighthouse is plaster or cement mortar. It is most convenient to use a ready-made mixture for plaster. In general, you can use any material from this series that is not prone to plastic deformation after setting, i.e.the composition should be relatively fragile, but, at the same time, reliably adhere to the outside of the basement (aboveground part of the foundation).
We recommend using a plaster mixture. Prepare it according to the manufacturer's instructions and place it on the crack in a 0.3-0.5 cm layer. The length of the marker is about 100-120 mm. The composition is applied so that the crack is approximately in the middle of the strip.
We use plaster mix
Complete each crack with at least two markers. Make one near the beginning of the fault, the second - at its end. The principle is shown in the image.
Marking house cracks and possible reasons for their appearance
Apply the plaster mixture with a narrow trowel. First, it is necessary to clean the surface of the base from dirt in order to ensure the highest quality adhesion of the beacon to the base.
We clean the plinth from dirt
Without waiting for the marker to harden, print a thin horizontal line on it. To do this, it is enough to gently press the side edge of a spatula, metal ruler or other suitable device into the mixture.
Number the markers by embossing the numbers with a nail or toothpick. Record in a notebook the date of the study and the serial numbers of the beacons.
Then watch. If the marker cracks, the foundation crack continues to widen. Every few days (the main thing is that equal time intervals are maintained between observations), measure the width of the crack on a plaster marker and record the results in a notebook. Such observations will help you draw conclusions about the rate of development of the deformity and predict the possible outcome.
Monitor the status of the marker
Follow the strip left with a putty knife / ruler. If parts of this mark are displaced in relation to each other, there are not only cracks, but also settlement of the structure. Common sediment varieties and their relationship to fracture patterns are highlighted in the above image.
This event is characterized by more pronounced information content and increased labor intensity. The bottom line is to prepare several (at least two) pits near the foundation. The pit is a pit with a depth to the base of the support and a length of about 100 cm. Choose the width individually, so that in the future it will be convenient for you to work with the foundation. To prevent the earth from collapsing, you can support the walls of the pit with unedged boards.
The described pit looks like this.
Pit for inspection of a brick foundation
The dependence of the pit dimensions on the features of the foundation is presented in the table.
Video (click to play).
Table. Recommendations for the selection of pit sizes
