The cost of repairing a completely or partially damaged basement depends on the type of foundation, the cost of materials and the repair and construction work itself. Restoring the strip foundation of a wooden building costs about 4,000 rubles per m2, and the cost of repairs at the base of the piles is already about 8,000 rubles per m2.
Estimated prices of construction companies performing foundation repairs, by type of work for houses with dimensions (6m * 6m) and (10m * 10m):
- Layout - cost (12,100 rubles) and (22,500 rubles), at a price of 100 rubles / m2.
- Excavation - cost (21,600 rubles) and (60,000 rubles), at a price of 600 rubles / m3.
- , reinforcement, concrete pouring - (72576 rubles) and (120960 rubles), at a price of 2800 rubles / m3
- Waterproofing - (8640 rubles) and (14400 rubles), at a price of 200 rubles / m2
Also, the cost may depend on the parameters:
- the slope of the earth's surface is not more than 2%;
- soil composition;
- groundwater depth;
- from the building project;
- ambient temperature (seasons of the year);
- distance to the repaired construction site.
Timely repair of the base of the house allows you to forget about the problem for a long time and keep the building intact, because wood is a durable material.
When is foundation repair necessary?
Buildings built of wood are considered to be quite lightweight and therefore they are usually erected on and not buried much. For 40-50 years, such a foundation regularly withstands the load, and then it is necessary to undertake repairs in order to prevent the destruction of the structure.
Problems that appear in the old and are a signal for the need for repair look like this:
- the building sags along with the foundation (the lower crowns of the structure may even be underground);
- door and window openings warp, as a result, they do not open and close well;
- cracks appear and increase on the walls;
- the base cracks and collapses;
- the porch changes its position.
Reasons for the destruction of the foundation
To plan repairs, you first need to analyze the possible causes of the destruction of the base of a wooden house. These may be such factors:
- the foundation is not laid deep enough for this region;
- not right ;
- violation of construction technology;
- Possibly low-quality building materials were used;
- the construction of other buildings near the house, which increases the load on the soil;
- completion / rebuilding of the structure itself and its too high loads on the structure;
- aging of basement materials;
- reinforcing mesh was not laid inside;
- incorrect or missing waterproofing;
- change in groundwater level;
- improper laying of drainage pipes.
Types of deformations
Also, when planning, the degree of damage to the foundation is taken into account:
- Minimal damage. Insignificant defects that do not change the bearing capacity of the foundation of the house.
- Moderate damage. These include cracks as a result of the destruction or subsidence of the base. With the help of beacons, it turns out: whether cracks are growing and how fast. As a beacon, you can use a sheet of paper, fixed on both sides of the crack, or by drawing a line of putty with a mark on the wall. If the cracks do not increase, then it is enough to simply repair them locally. In the event of the destruction of lighthouses, it is necessary to quickly save the base of the structure, since the deformations are already catastrophic.
- catastrophic damage. The base of the building has serious defects that threaten safety, serious repairs cannot be avoided.
- irreparable deformations. The foundation is completely destroyed and its restoration is impossible.
What repairs are possible
With minimal damage, if the owner wishes, only the top layer is cosmetically repaired. Damage of moderate severity requires a complex of works on sealing cracks: expansion, cleaning, priming and sealing with cement mortar or other mixture. In the case of catastrophic ones, the question is whether to strengthen the foundations or completely replace them.
Advice. The best time to carry out repair work on the base of the house is the period when the groundwater decreases - from May to November.
Types of jobs
Strengthening the foundation of a wooden house
Strengthening the foundation of a wooden house is carried out subject to the stability of the soil. and, for example, in the case when it is necessary to rebuild the building, the foundation is slightly damaged, but it will not withstand the additional load.
A set of works to strengthen the strip foundation:
- A trench breaks out along the perimeter of the base.
- The surface is cleared of soil, old waterproofing.
- Holes for reinforcement are drilled 1 mm wider than their thickness.
- The reinforcement is driven into the holes, it will connect the old and new foundations.
- New reinforcement is welded to the fixed part to create a reinforced belt, the rest of the strapping is done with wire.
- Formwork is fixed.
- The formwork is filled with concrete, it must completely harden.
- The new foundation is being waterproofed.
- Performed .
This approach renews the foundation, the load of the structure is redistributed taking into account the larger supporting surface, its strength and stability increase, and the service life is extended for decades.
Strip foundation repair
If cracks appear on the surface of the base, repair work should be taken up.
If a single crack is found (apparently, networks are connected in this place), then a set of works is carried out, as when strengthening the base, only locally.
When there are several cracks, it is imperative to understand the reasons, which may be as follows:
- subsided soil under the building;
- the reinforcing cage was not made;
- the loads on the base were incorrectly calculated;
- the foundation is made of concrete of the wrong grade;
- there are no weirs;
- drainage close to the foundation.
In this case, you need to determine whether the cracks are increasing - this is done with the help of beacons. If they do not increase, then the cracks are simply sealed, otherwise, more serious repair work is ahead.
Foundation base like plasticine
The softness and plasticity of the base material shows a high percentage of clay and a low percentage of cement. The only way out is to remake the basement.
Shedding strip foundation
There may be several reasons:
- very liquid concrete was used;
- construction work was carried out in winter from a concrete mixture without antifreeze additives;
- clay is added to the composition of the mixture, pores are formed in it, collecting water, and then freezing and thawing will destroy the concrete.
It is important to make repairs in time, which will not allow destruction, otherwise, with large damage, only the option of a complete redo will remain.
Foundation repair steps
The largest complex of construction works must be performed with a complete replacement of the foundation or its reconstruction.
The technology of work is as follows:
- to reduce the load on the foundation, the building is completely freed, including, if possible, the floor and the stove;
- based on the calculation of the weight of the building, a jack is selected or, if necessary, several;
Advice. A light-weight structure can be lifted with the help of a beam brought under its corners and resting on a log. Using a lever, when pressing on the bar, the building rises.
- trenches are dug around the entire foundation or only in places where it is required to raise the house;
- jacks are installed in reliable, stable places, they are brought under opposite walls (in the case of a complete raising of the building);
- carefully, smoothly, slowly, the building rises; to fix the structure in this state, wedges are inserted between the house and the foundation cushion at intervals of 15-20 cm, the same is repeated with the two remaining opposite sides.
When it is necessary to lift the whole house, the lower rims will be subjected to the greatest load and therefore they are preliminarily tightened with a steel hoop or boards are stuffed.
Advice. You can’t immediately raise the wall high, because the logs can move and the ligaments can be damaged.
In the case of restoring the foundation, the walls rise by at least 50 cm. For fixing in a raised state, concrete blocks are used that will cope with the weight of the building, large boards are placed under them to prevent the blocks from sinking into the ground. Next, you can repair the foundation.
At the final stage of repairing the foundation, after making the mesh from the reinforcement, it is necessary to perform the formwork. Inside the formwork, make communication outlets and places for installing jacks from pipe scraps.
The formwork walls are supported and concrete is poured. All work should be completed within one day and after the concrete mixture has completely hardened, the building can be returned to its place.
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 thoroughly 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.
It is possible to 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 frame - 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 placed. 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 post 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 incidents and give the wooden house a new life.
Foundation repair is a costly and complex undertaking, in order to perform it correctly, you need to know the principle of the device, the causes and signs of foundation destruction. A wooden private house is very common in our area, which is not surprising, because wood is an affordable material, construction costs are relatively low, and the built house will be environmentally friendly and warm. These are the undoubted advantages of a wooden structure. There are also disadvantages, but they do not appear immediately, but after some time of operation.
Most often, the owners of wooden houses are faced with the fact that the house is "bursting at the seams." Windows, doors warp, walls sag, cracks appear. All these visual defects are caused by one reason - the destruction of the foundation. To prolong the life of the house, it is necessary to eliminate this destruction in a timely manner. This will require strengthening or reconstruction of the foundation (restoration), complete (overhaul) or partial (elimination of cracks).
It is worth noting that repairing the foundation of an old wooden house is not an easy undertaking, so it is advisable to entrust it to professionals. But, you can do the work yourself. The main thing here is the time factor. The problem must be fixed as soon as it is discovered.
Reasons for the destruction of the foundation
Before proceeding with a detailed study of how to repair the foundation of a wooden house, you need to figure out what caused its deformation. Two factors can contribute to this:
change in the bearing capacity of the soil. This is due to an increase in the load on the foundation, and hence on the ground under it. The reason may be improper drainage of rain / melt water or an increase in the level of groundwater, which leads to erosion of the soil. The erection of other buildings near the house also increases the load on the soil. As a result, the soil, as it were, is squeezed out from under the foundation of the house, which ultimately can lead to subsidence of the house or its distortion.
loss of strength of the material from which the foundation is made. Among the main reasons are the following: the wrong choice of the type of foundation, the impact of water, the wrong brand of concrete that was used during construction, the incorrect calculation of the depth of soil freezing, and the violation of device technology.
Identifying the cause of foundation failure provides a starting point for research.
Types of deformation of foundations
The second point that needs to be taken into account is the identification of the degree of damage to the foundation. According to the criterion of maintainability, they can be conditionally divided into 4 types.
1. Minimal damage.
These include the partially exfoliated finish of the foundation of a wooden house. Such defects do not significantly affect the bearing capacity of the foundation. In addition, they are visible to the naked eye and are eliminated without any problems.
2. Injuries of moderate severity.
These include the appearance of cracks in the foundation of the house due to subsidence or destruction of the foundation. In this case, you should be more careful, because. crack crack discord. First of all, its direction is determined. As a rule, horizontal cracks in the foundation are the least dangerous, but vertical or zigzag cracks should alert you. It will also be clarified whether the subsidence of the foundation is temporary or is it progressive.
The nature of the destruction can be determined using beacons installed on the crack (see photo).
Plain paper can be used as beacons, but it is worth remembering that when moisture gets in, the paper gets wet and will no longer give a complete picture of the behavior of the crack. Gypsum plasters are suitable for use. But the easiest way is to apply a little putty on the wall and draw a straight line on it with a spatula and make a mark. Such a beacon is good because it breaks at the slightest movement of the surface. Installing a beacon will allow not only to notice the increase in the crack, but to determine the rate of destruction.
Important. The beacon must be installed on a clean, dry wall to prevent its movement. The beacon thickness should not exceed 5 mm.
With temporary subsidence of the foundation, the beacons will remain motionless. That is, there is a high probability that the soil under the foundation has moved a little, taken its place and does not intend to move anymore. Therefore, it is only necessary to carry out routine repairs of cracks in the foundation.
Elimination of cracks:
- widen the crack
- clean it from falling parts and dust;
- treat with a primer;
- seal the seam with a special mixture or cement mortar.
The destruction of lighthouses indicates that the fault in the foundation or wall is increasing. This means that sealing cracks will not help, it's time to take urgent measures - this type of deformation can be classified as catastrophic.
3. Catastrophic damage.
These are foundation defects that can lead to the destruction of the house. Of course, it is desirable to repair the foundation under a wooden house in time, but there are times when the moment is missed.
Then the technology for carrying out repair work will be determined by the type of foundation. The most popular of which are columnar and tape. In each individual case, each owner decides for himself whether he needs to strengthen the foundation or replace it completely.
4. Fatal deformations.
In this case, the state of the foundation is so deplorable that there is nothing to repair. It is usually easier and cheaper to destroy an old house and build a new cottage in its place that meets all the requirements of a modern person.
Repair of the strip foundation of a wooden house is somewhat more complicated, so we will dwell on it in more detail.
Strengthening the foundation of a private house - ways to strengthen
The reinforcement method is chosen when the deformations of the foundation are eliminated, and the soil under its pillow is stable. Or if there is a need for an add-on to the house, and the existing foundation cannot cope with the increasing load.
Strip foundation reinforcement technology - instructions
- dig a trench around the perimeter of the foundation. Its width should be sufficient for comfortable work and take into account the fact that the thickness of the foundation will increase;
- clean the surface of the foundation from the soil;
Advice. You can clean the surface well using a metal brush.
- drill holes. Its diameter should exceed the diameter of the reinforcement by 1 mm. This is necessary for a more dense installation of metal rods;
- hammer the rebar into the holes. Thus, the new foundation will be securely connected to the existing one;
- make a reinforced belt. To do this, reinforcement is welded to the installed pieces;
Advice. It is advisable to weld the reinforcement in only a few places, and carry out the main part of the strapping with wire. Such fastening does not require special skills and tools. But if it is present, the reinforcing belt is not deformed when concrete is poured and hardened.
- formwork is installed;
- concrete is poured. After the concrete has hardened, the formwork is removed, and the reinforced foundation stands for a few more days;
- the waterproofing of the new foundation is being carried out;
- a blind area is made, which will allow water to be diverted from the foundation.
Strengthening the foundation of a wooden house allows you to redistribute the load of the building over a large area. As a result, the foundation will no longer sag or collapse.
Complete replacement of the foundation of the house
Often the foundation sags so much that water can freely flow into the room. In this case, you need to figure out how to raise the foundation of a wooden house? Or the old foundation can no longer cope with the load that falls on it, and then the foundation is reconstructed.
Replacing the foundation under a wooden house - technology
- maximum reduction of constant and variable load on the foundation. To do this, everything that can be taken out of the house is taken out, it is even advisable to dismantle the floor and disassemble the stoves. The exception is furnaces on a separately poured foundation. Naturally, tenants are also evicted for the duration of the renovation;
- load calculation (weight of the house). Weight is easy to determine, having at your disposal data on the density of the wood from which the house is built and the total cubic capacity of the wood used. The cubic capacity is calculated based on the dimensions of the house and the thickness of the walls;
Advice. A small and light wooden house is raised by means of a vag. To do this, the timber 80x80 is started at the corner of the house. Further, the timber rests on a log. By pressing on the beam, you can raise the house like a big lever.
- choosing a jack to raise the house. Depends on the weight of the building, the load capacity of the jack and their number;
- digging pits (trenches). It breaks out around the entire perimeter of the house or only in those places where raising the house is required. Its presence simplifies access to the foundation. In addition, the appearance of water in the pit will make it possible to understand the level of groundwater occurrence;
- housekeeping establishment. In order for the raising of the house to go smoothly, you need to correctly install the jack. It is installed only in reliable places, without destruction and damage;
- house lift. You need to raise the house carefully, slowly, and most importantly evenly;
Advice. To insure yourself in case the jack cannot cope with the load or is installed unsuccessfully, you need to start wooden wedges between the house and the foundation pad. It is advisable to start wedges every 15-20 mm.
Important: to build a foundation for a wooden house, you need to raise the entire structure. Considering that the house is wooden, the maximum load will fall on the lower crowns. To prevent them from sagging, you need to pull off the lower crown with a steel hoop or fill the boards.
- demolition of the old foundation. If the budget is very limited, and the condition of some parts of the foundation is satisfactory, then partial disassembly can be performed, i.e. remove only the destroyed foundation. However, the cost of work from this will not decrease significantly, but the quality of work may suffer;
Advice. It is necessary to dismantle the old foundation to the ground.
- arrangement of a sand-cement cushion for the future foundation. Despite the fact that the foundation is laid under the finished house, the pillow is an important part of it;
- installation of concrete or brick supports in the corners of the house. It is also possible to install piles. They will reduce the load on the foundation in the future. The height of the support is equal to the height of the new foundation;
- reinforcement. After the columns are installed, the reinforcement is installed. The reinforcing belt will give the foundation strength. We remind you that his armored belt for the foundation is carried out using wire, not welding;
- formwork installation;
- pouring concrete. The foundation must stand for several days to gain strength. After that, the formwork is removed, and the foundation is left open for another 1-2 days;
- waterproofing. To protect the wood of the house from decay, lay a layer of waterproofing on the foundation. Roofing material is excellent for these purposes;
- lowering the house. The house is sinking as slowly as it rose;
- Finishing work. This includes complete waterproofing, cladding, drainage and blind area.
It can be seen from the description that replacing the foundation under a wooden house is a rather risky and time-consuming undertaking, for the implementation of which it is advisable to invite specialists.
How the house is raised and moved to a new foundation in practice can be seen in the video
Using the methods described above, you can repair the strip foundation of a wooden house. But what about those who have a columnar foundation?
Repair of the columnar foundation of a wooden house - technology
- the house rises to the calculated height. The height should be sufficient to carry out the work and at the same time not contribute to the strong sagging of the lower crown.
- tilted poles are dismantled. It is worth noting that the dilapidated support pillar must be removed, and the tilted one is simply leveled.
- soil is selected at the installation site of new pillars. We remind you that the pillars are installed at the corners of the building and at the junction / intersection of the walls.
- a sand-cement cushion is arranged under the pole.
- column is being reinforced.
- concrete is poured.
- steel or wooden beams are being installed, which take on the entire load from the weight of the house and transfer it to the poles.
- the building goes down.
If you need to replace one or two pillars, you can do it as follows. In the place where the pole is installed, which is to be replaced, a tunnel is made. The tilt angle is 35°. A pipe is inserted into it and filled with a solution. After solidification, the old pillar is removed and the new one is leveled. The process is more clearly shown in the photo.
It is worth noting that the repair or complete replacement of a pile foundation is much easier and faster than a strip foundation and takes only a few days, after which the house can be operated normally.
Repair of brick and rubble foundation - replacement with a monolith
In times of total scarcity, i.e. during the construction of the main part of the houses, the foundations were built of brick (both strip and columnar). Due to the fragility, repairing the brick foundation of a wooden house usually involves replacing the brickwork with a more durable material - concrete. This reinforcement technology is applicable to the foundation of rubble stone. The method was described on the forum "House and Dacha" and judging by the reviews, the technique has shown itself well in practice.
To carry out repairs, you will need
- Concrete solution.
- Fittings.
- Corner for the manufacture of supports.
- Jacks for lifting a house with a lifting capacity of 20 tons.
We dismantle the old rubble laying of the foundation (or brick) in small sections of half a meter.
The released fragments at the base of the house are needed to install the jack and further transfer the weight of the house to the metal supports.
In place of the destroyed base, a base plate for the jack is made. The platform must be strong and stable, poured from concrete with mandatory reinforcement. 
If the ground is hard, concrete paving slabs can be used. 
Hanging the house with jacks. It is necessary to lift alternately in all openings. 
When the house is hung out, it is necessary to install supports pre-welded from the corner, on which we lower the house. 
Scheme of a steel support for a house - dimensions and principle of the device. 
After transferring the weight of the house to the supports, the formwork is arranged from the inside. 
Reinforcement is laid and knitted inside the supports. 
Upon completion of the reinforcement, the outer part of the formwork is installed and concrete is poured. Thus, the foundation is being replaced under the wooden house.
Conclusion
After reading this article, you have gained an idea of how to repair a damaged foundation, how to strengthen the foundation of a wooden house, and in what cases it must be completely replaced. Using this information, you will gain sufficient knowledge to do the work yourself.
Foundation repair. Causes of destruction. Restoration of the foundations of brick and wooden buildings
In any structure, the base is the most important part, since it is this structural element that carries the main load and protects the structure from the penetration of dampness from the soil. But sometimes, due to the influence of adverse factors and because of the long period of operation, it is necessary to repair the foundation - this work can be done with your own hands only if you know all the basic nuances of the process. In the article we will consider some options for solving the problem.
Cracks are the first sign of problems with the base
Reasons for the destruction of the foundation
Let's figure out what factors have a negative impact on the design:
| ground subsidence | If a shallow-depth version of the design is used, then a situation is not ruled out in which the soil will sag during freezing and thawing. Often there are cases when the lower part of the base is washed away by groundwater, which leads to deformation of the system and can cause the destruction of individual sections. |
| Foundation extrusion | Such troubles happen only with shallow foundations and occur when the ground freezes and pushes the underground structure up. That is why such options are rarely used, especially if winters are cold in your area. |
| frost heave | If the base is not very strong, then when freezing, the soil can break through the structure from the side, which will cause cracks and a shift in individual sections relative to the plane of the main system. It is worth noting that such situations are most often found in old buildings, where the material is already weakened and the surface layer has begun to collapse. |
| Base overturning | Most often this is due to the fact that groundwater washes the soil from the outside or inside and there is no support at the side plane. This is the most dangerous situation, as it can cause the destruction of the entire structure. |
Important!
There may be other reasons for the problem.
Before proceeding with their elimination, you need to understand the issue in order to exclude the appearance of such troubles later.
The processes occurring in the soil are most often the cause of structural failure.
Description of some types of work
We will talk about the most common situations and how to properly fix the problem. Much depends on what material the house is built from - brick or wood. It is on this basis that we will divide all the work.
brick buildings
Repairing the foundation of a brick house begins with checking how quickly the process of destruction or subsidence occurs. To do this, a paper tape is glued to the cracks, which is checked daily, if it breaks within a few days, it means that it is urgent to start strengthening the structure in order to avoid big problems.
The first way to solve the problem is to saturate the soil under the base with cement mortar.
The foundation repair technology in this case is as follows:
- A hole is dug near the structure at an angle of 35 degrees to the surface.. The depth should be such that the lower part is located at the bed stone or near the crushed stone pillow. It is important that you free up space and provide access to the soil, which bears the main load;
- Next, a pipe with a diameter of 150-200 mm is inserted into the dug hole, through which cementation will be carried out. A liquid cement mortar is prepared for work, which is poured until the soil is completely saturated (that is, after filling the pipe, the composition will not decrease for at least 2 hours);
Saturation of the soil with cement makes it possible to make the base under the foundation much more reliable and stop the destruction of the structure.
- After 48 hours, the procedure is repeated to ensure the best result.. If necessary, such work can be carried out in several parts of the system. Such repairs to the strip foundation will be effective in cases where problems arose due to the weakening of the soil or its leaching by groundwater;
- After the work is completed, paper is again glued to the cracks if it broke within two weeks, then you will have to use more radical methods of work.
A broken foundation can also be repaired by drilling the structure itself and strengthening it and the soil with cement mortar.
A more radical method is the following option to strengthen the base:
- A trench 20 wide and at least 35 centimeters deep is dug around the entire structure.. If the ground is not very hard, then you can strengthen the walls with boards, it is important that the edges do not crumble;
Sometimes when digging a trench, big problems are found in the form of collapsed sections.
- Further, holes are drilled in the surface, the diameter of which should be 10 mm, and the depth is about 5 cm less than the thickness. For work, a puncher with a drill of the appropriate length is used, the tool must be powerful enough, since the work is associated with high loads;
Specialists use equipment with an emphasis to facilitate work
- Then, pieces of reinforcement are hammered into pre-prepared holes. with a diameter of 12 mm, they should protrude on the surface by about 50-100 mm. The next step is to construct a reinforcing belt on the surface, which can either be welded or fixed with a knitting wire. It is important that the design is reliable, because the strength of the final result depends on it;
When building, do not save on materials, it is better to achieve excessive than insufficient reliability.
- After, if necessary, formwork is installed and pouring is carried out, for which concrete grade M200 is used with a filler of fine or medium crushed stone. It is important to carry out the entire workflow in one step in order to achieve maximum structural strength;
- Such a reinforced concrete ring allows you to distribute the load on the old and new part of the foundation and eliminate the problems with destruction and subsidence.
Important!
In case of problems on only one side, a similar workflow is carried out only there.
This allows you to reduce the complexity of the work.
The repair of the columnar foundation is carried out in a similar way, with the only difference being that it is necessary to make a formwork around each support, and then pour concrete. This allows you to increase the bearing capacity of the elements at times.
wooden building
There are very common cases when it is necessary to repair the foundation of an old wooden house. Most often, the foundations are in such a deplorable state that a complete reconstruction is necessary.
The process is as follows:
- First of all, it is necessary to simplify the design as much as possible.: remove all furniture from the building. Next, you need to punch holes in the foundation for the location of metal channels, which should be installed in increments of one and a half to two meters, depending on the reliability of the structure and the features of its design;
If the lower crown is rotten, then it is better to make holes right in it so that the structure rests on strong logs.
- As for raising the structure, there are two main options.. The first is the use of manual jacks, they will need quite a lot, while working, you should constantly monitor the uniformity of the process so that the structure does not heel. The second option involves the use of special equipment, it will take a few minutes to work with it, but you will have to pay specialists who provide such services;
You can lift the house with hand tools, but it will take a lot of effort.
- After lifting, be sure to check that the structure is stable. and will not fall on you when working. Next, a trench of the required width and depth is dug, a crushed stone pillow is poured into it and a reinforcing frame made of reinforcement is installed;
- Filling the foundation is no different from ordinary work of this kind. It is necessary that the structure stand for at least 3 weeks in order for the concrete to gain strength characteristics. After that, the surface is waterproofed and a house box is lowered onto it.
The second solution to the problem is to repair the foundation with screw piles, this type of work has the following features:
- First of all, you need to raise the house, this is carried out in the same way as described above, so we will not dwell on this process in detail;
- Next, you need to screw the piles, their number and length are calculated depending on the structural features and the depth of soil freezing. The elements are located on the outer side of the old base and can be wrapped both with the help of special equipment and manually;
- After screwing in, the top edge of the elements is aligned, if necessary, the protruding elements are cut off to the desired height, it is important to achieve minimal differences;
- Next, you need to weld the frame from the channel and profiled pipe so that a reliable foundation is formed, on which the house will subsequently be installed. The size and thickness of the products must be sufficient to withstand the loads without any loss of reliability;
- Applying a protective anti-corrosion coating- an important part of the work on the protection of metal elements, use only high-quality compounds for these works.
Pile construction will be much cheaper than a concrete foundation
Of course, when apartments are being renovated, there is no foundation as such, but when working in the private sector, you will have to pay close attention to this part of the structure.
Output
Naturally, the repair of the foundation of a wooden house can be carried out by analogy with a brick one, it is not necessary to raise it at all. The most important thing is to choose the option of strengthening the structure, in which you will achieve the best result. The video in this review will help you understand the work even better, and if you have questions, ask them in the comments below.
The old wooden house solves the problem of a damper belt between the constantly changing earth's crust, coupled with the external environment under weather conditions and a man-built house, which provides peace and stability.
This design is under constant pressure from all sides. Time is relentless for him.
For a long service life of the house, control over the state of the supporting structure is necessary. If the development of destructive processes is stopped in time, then housing will serve as a fortress for a long time. This problem can be solved by renovating the house.
Factors that bring changes to the design of the foundation
The foundation is the first to assume the full force of the impact of human activity and the external environment.
During operation, constant changes occur that affect it:
All these actions strictly lead to wear of the bearing part of the building.
Foundation inspection methods for structural wear
- visual method. It consists in the periodic inspection of the building and the structure of the foundation. Detecting the presence of cracks in the walls, peeling of plaster or finishing materials, deformation of the dumping lining between the base of the wall and the foundation, subsidence of the level in.
Inside the building, distortions of openings and doors can be observed, leading to difficulty in the porch of the shutters and canvases. The occurrence of cracks and cracks in. The appearance of a change in the level of the floor covering.
- Instrumental research is carried out using a water level, level, theodolite or level.
Beacons made of paper are used, with the help of which it is possible to identify the dynamics of the violation.
The data obtained is processed and the indicators are compared with the design figures that were used during the construction of the building.
In case of small deviations, no action is taken. With approaching critical indicators, you should not hesitate. The sooner the problem is fixed, the longer the building will last without the need for major repairs at great expense.
The main types of foundations for a wooden house
Buildings made of wooden materials are lightweight compared to houses made of and. Therefore, shallowly buried foundations are used for them, mainly of several types:
Foundation repair activities
Foundation types
Basically, the columnar foundation and the strip structure are more likely to be destroyed.
If a decision is made to repair the foundation of the house based on the results of the inspection, it is necessary to identify the place with the greatest damage. This is determined by comparing the nature of the damage, smaller to larger. Then the possible cause that led to the violation is determined.
For example! The subsidence of the soil led to the appearance of the foundation. The reason may lie in the actions of groundwater, a violation of the removal of melt water and precipitation, the construction of an extension or the digging of an additional pit, which caused the movement of the reservoir.
Based on the results of the inspection, an assessment is made of the condition of the structure of the foundation of the house
- small damage with the lack of development dynamics for the worse. Subject to cosmetic repairs and further monitoring
- Strong damage. There is a development dynamic. Cracks are visible visually and have the character of deep horizontal or vertical lines. You can see the presence of small cracks going along the sides. Peeling of plaster over the entire area of the affected area. At this stage, a decision is made to repair a local area with a partial replacement of the damaged area or its strengthening. The option of a complete phased replacement of the entire perimeter of the base of the house is possible.
- Complete destruction half or more of the foundation. In this case, it is proposed to demolish the house or dismantle it for the construction of a new foundation and a new building. This option often becomes cheaper than the repair of the foundation.
The progress of work on the repair of the damaged section of the base
Pillar foundation repair
To repair the structure of the base of the house, jacks of increased carrying capacity are used. The process begins with the release of the premises of the building from heavy and fragile things, furniture, appliances, dishes, mirrors. In special cases, window sashes are removed to prevent deformation. Next, the main repair activities begin:
- A bunch of pillars is removed, serving as protection for the underground space.
- At least 4 jacks are brought under the walls of the house.
- Slowly, with the help of hydraulic installations, the whole house is raised above the level of existing piles by 10 centimeters.
- To avoid sagging of the lower rims around the perimeter of the building, they are hammered together with the upstream parts using long boards.
- Damaged parts are dismantled, and lopsided poles are leveled. Soil is dug around them, poured into the pit.
- For new piles, pits are dug out, new parts are installed in them and poured with concrete. Their upper edge must correspond to the level of previously installed supports.
- After the concrete has gained strength over time, the house also slowly sinks to its original place.
- Finally, a bunch of pillars from the new material is installed.
Strip foundation repair
This action consists of several processes:
- Repair of the damaged part of the supporting base with its partial replacement and reinforcement along the entire perimeter of the foundation. This is a more complex process, requiring the complete dismantling of the damaged section of the foundation. It is necessary to dig a trench again in the future, and install the formwork.
Pour concrete and allow time for curing.
If the cause of damage is identified, for various reasons, it is necessary, in addition to repairing the site, to strengthen the entire perimeter of the base.
To do this, dig a trench along the entire perimeter of the existing foundation. Clean it from plaster and earth. Install reinforcing pins from reinforcement into the walls of the old foundation. A reinforcing structure is tied to them with wire. Exposed and poured with concrete. After seven days, the formwork frame is removed. The new reinforced foundation is subject to finishing and further operation.
Complete replacement of the entire foundation
Large-scale restructuring involving complex processes:
Dismantling of sections of the base for the installation of jacks.- Slow rise of the building at least 15 centimeters from the previous level.
- Complete dismantling of the emergency foundation.
- Device with trench reinforcement for a new foundation. Ensuring measures for the diversion of groundwater, melt water and precipitation.
- Installation of formwork along the entire perimeter with reinforcement with steel cores with a diameter of at least 12 mm. A larger foundation is planned to increase the margin of safety.
- Then concrete is poured using a deep-seated one to remove air bubbles. Time is given for strength gain of at least 14 days.
- The formwork is dismantled. The foundation stands in this state for another 10 days.
- Next, coating and pasting vertical waterproofing of the supporting base with materials is carried out, followed by backfilling with soil.
- To protect the walls of the house from getting wet, it is laid under the crowns on the foundation.
- The house is slowly lowered to its original place.
- Finally, the outer side is finished.
