DIY repair of cracks in the foundation

In detail: DIY repair of cracks in the foundation from a real master for the site my.housecope.com.

View of a crack in the strip base of the structure

Any foundation, regardless of complexity, device and characteristics, is damaged after a while. This can be natural wear and tear, washing of the sole by groundwater or man-made factors. But the base, which is already damaged in the early stages, must be repaired immediately in order to then prevent the complete destruction of the supporting structures of the house.

In some cases, repairs can be done with your own hands without the use of powerful construction equipment. Cracks that are insignificant in size and depth are often repaired on their own. Considering that strip foundations remain popular among private developers, they can be found under residential buildings, outbuildings and country houses. It can withstand significant loads, is easy to install and does not require specialized knowledge.

Determination of the causes of cracks in the strip foundation

There are many reasons why the base has cracked. The foundation is influenced by both external and internal risk factors. The main reasons due to which cracks appear in the house are as follows:

There are other reasons due to which gaps appear in the bases with their further destruction. Therefore, before starting restoration work, you need to carefully examine the damaged area and find the cause of the deformation of the structures.

Installation of beacons on the crack of the strip base

First, you need to decide what is the state of damage in general, and whether the crack grows further. To do this, you need to do the following:

Video (click to play).

Thoroughly clean the crack from adhering dirt, deformed concrete.
Rinse lightly with water, preferably under pressure.
Install special beacon markers on the upper, middle and lower edges and indicate the time and date of installation on them.
The marker (lighthouse) must be left in one position and regularly check in what condition it is. If it ruptures over time, then the crack continues to grow and measures must be taken to eliminate it. If the marker remains in place unchanged, then this may be an operational defect in the concrete itself, as well as a displacement of the reinforcing belt near the crack. Such situations often arise during the winter-summer period, when the ground arbitrarily changes its level.
It is recommended that all observations of the state of the lighthouses be regularly recorded in a notebook, since experts will be able to quickly find the cause of their occurrence using the data obtained and propose to eliminate it in an effective way.

All preparatory work is easy to do with your own hands; ready-made factory gypsum strips with thickenings along the edges can be used as beacons. Instead, glass beacons with a ready-made scale proved to be effective. The principle of installation and operation in them is identical.

The foundation is cracked. Measurement of the crack size in the strip base of the house.

Cracks are of several types:

Hair cracks. They are small and thick. In most cases, they arise due to deformation of the outer protective layer of the plaster. Such cracks in the foundation of a country house have nothing to do with the deformations of the base; they are eliminated by repeated plastering of the surfaces.
Horizontal cracks. They arise during the operation of the house, therefore they do not affect the safety of the structure.
Shrinkage cracks. They arise due to incorrect calculation or errors in the construction of the foundations; the foundation could not have settled.When uneven shrinkage of the foundation sole occurs, then the load on one side of it is higher than on the other. The result will be a slope in the corner of the building, and cracks will grow from the shrinkage point to the surface relatively evenly.
If, after a few days after pouring concrete into the foundation, cracks appear on it, this is a violation of the construction technology. In such cases, the damaged area is often dismantled and replaced.

If cracks are found in the strip foundation on an already erected house, then this is already a big problem for the owner. Repairing a strip foundation is an expensive pleasure, because here you need to strengthen the structure, raise individual segments of the base, and only then proceed with the repair. In some cases, only the construction of an additional foundation, its reinforcement remains the only correct decision.

The basis for a shallow strip foundation is insulation and a blind area.

Country houses are often built on strip foundations, as this is cheaper. If the country house is made of wood, then cracks appear extremely rarely due to the low mass of the structure. But if the country house is made of bricks or foam blocks, then cracks will be a frequent occurrence in such structures due to uneven loads.

One of the ways to eliminate a crack in the strip foundation of a country house

First, you need to clearly define the problem, after which the crack appeared. If this is an artificial wear of the foundation material, then you can do aesthetic repairs with your own hands. But if this is a violation in the bearing capacity of the structure, then reinforcement is no longer necessary.

Small cracks of shallow depth can be repaired with special mortars. To do this, the crack is completely cleaned of dirt, washed with water and filled with a primer. After the primer has dried, the entire crack must be repaired, and all cracked sections of the foundation must be processed. It uses frost-resistant finishing plaster, grout or epoxy resins.

If the damage is significant, then the repair will already be quite costly and it is already more difficult to do it with your own hands. Thus, there are several repair technologies:

Reinforcement of the damaged section of the foundation with a new wall made of bricks or concrete blocks with additional reinforcement.
Raising the house and strengthening the damaged area with special pillars along the entire length.
Extension of the outsole. Then you need to dig a trench up to the very bottom and strengthen the walls with formwork. Install the reinforcement inside, connect it to the damaged foundation and fill everything with concrete. At the end of the work, dismantle the formwork and fix the waterproofing ball instead.
You can also use the injection method, but it is practiced in cases where it is technically feasible to stop the growth of cracks in other ways.

If you have a house made of foam blocks or bricks, then the lighthouse should be in the shape of a figure eight and its ends should be resting on the banks of the crack under study, and the middle of the figure eight beacon itself runs exactly along the crack. It is worth noting that if you use a beacon - a cake, then it will fall off the crack bank rather quickly and, accordingly, you will not get any result!

In terms of time, it is best if, within one year, about once every two months, you write down observations about the state of the lighthouses in a notebook, if there are several of them, if it is cracked, it is not cracked. We write down the data on the deployment of the lighthouse in millimeters and make a visual graph.

In practice, pouring the sole or expanding existing walls is not used, because the cost of all work will be commensurate with the construction of a full-fledged strip foundation. It is better to make load-bearing masonry or install bored piles.

A crack on the wall of a house can cause panic among its owners.What if there are signs of very serious housing problems? In fact, not all is lost, and you can fight for the safety of your home.If cracks begin to appear on the walls of the house, every effort must be made to determine the true cause of their appearance.
If the foundation of the building is intact, then the reason for the cracking of the walls is the gross mistakes made in the technology of their construction and operation. The nature of the problem can be individual and most unexpected. Finding one is likely to require the help of experienced civil engineers.
But in most cases, the problem is found in the fact that the foundation under this wall has cracked. Image - DIY repair of cracks in the foundation

If shrinkage cracks are visible in the foundation of a building, then with a high degree of probability:

the foundation burst, its cast monolith or block masonry;
shrinkage of the pile structure has occurred;
the destruction of the pillars of the columnar base began.

The reasons for cracking the foundation of a house are almost always mistakes made in its design and construction:

errors in determining the bearing properties of the soil;
incorrect determination of the degree of water cut in the area;
wrong choice of foundation depth;
low structural strength of the foundation;
persistent high humidity in the basement and subfloor caused by improper use of the home.

The fight against cracks in the foundation and walls of the house comes down to two organizational and technological methods:

elimination of the cause of the emergency;
repair of cracks and strengthening of damaged foundations.

If the foundation and walls of the building begin to crack, they should be monitored immediately.
A crack in the foundation can be located:

Horizontal cracks in the foundation can be caused by technological errors made after pouring it. They are not so dangerous for the stability of the building as a whole and must be repaired in the course of its facade renovation. Large diagonal and normal cracks in its foundation can pose a great danger to the integrity of the house.
Microcracks (up to 1 - 2 mm) in the foundation could appear for a number of reasons. They are not yet dangerous, but they must be repaired, since water and frost will cause them to expand and gradually crumbling concrete in the damaged area.

Large cracks (about 10 mm) must be monitored. To do this, a beacon is applied to the crack (a strip of cement or plaster mortar). If after a few weeks the beacon turns out to be torn, then things are bad: the crack continues to expand, urgent measures must be taken. If the beacon remains intact, then not everything is so bad. Most likely, the building gave a slight initial shrinkage, which soon ceased. In this case, it will be enough to patch up the cracks and continue monitoring them.
If the foundation of the house is cracking further, or an emerging through fault is identified, measures must be taken to reanimate the building immediately.

If frosty-heaving soils and a high level of groundwater are detected at the site, the following is performed:

construction of a drainage system of an open (trench) or closed (ceramic pipes) type, drainage of groundwater, lowering their general level;
device along the perimeter of the house with a wide drainage and insulating blind area (up to 3 - 4 m wide) for draining the upper layers of the soil directly under the building.

With constant humidity in the basement or subfloor, a search for water supply sources, repair of water supply and drainage communications are carried out.
If the cause of the cracked foundation is determined by errors in the calculations of its strength, in this case it is necessary to make a decision and make a project for its repair or reinforcement.

In most cases, it is not possible to completely unload the foundation of a brick or reinforced concrete house, therefore only preventive and partial repairs are made on it, which fix the damage already received, stop and prevent their development.
A feature of light wooden buildings is the fundamental possibility of carrying out a complete repair of their foundations.
Preventive repair of the building foundation is carried out at the initial stages of its cracking, if the causes of destructive processes are identified and eliminated, and as a result of long-term monitoring of the growth of the detected cracks, no cracks have been identified.
The purpose of preventive repair is to seal the cracks that have appeared in the foundation and restore its integrity.
During such repairs, the following is performed:

cleaning cracks (with brushes, compressed air, water jet) from dust and dirt;
cutting a crack with a chisel so that its hidden cavities and deep passages are accessible;
sealing all passages and cavities with a special putty or resin.

Strengthening the foundation is carried out if measures to eliminate the causes of its destruction have not yielded results, and the expansion of the cracks continues.

The structure of a wooden house is much lighter and more solid than a brick building. The wooden blockhouse can be fully raised on jacks without destroying it.
If the crown of a wooden house was attached to the foundation, then it must be detached. If the crown was fastened with vertical pins, then in order not to disassemble the entire frame, it is necessary to find the exit points of the pins and cut them off with a grinder at the level of the upper cut of the foundation.
To raise a wooden frame, you must:

prepare the required number of jacks: two units for each jacking point (from the outer and inner sides of the wall, in increments of 2.5 - 3 m, plus for each corner of the building);
prepare supports for jacks:
under their lower sole - supporting reinforced concrete slabs or metal slabs (usually trimming channels);
for the upper support - scraps of metal I-beams are hammered under a wooden frame so that their ends serve as upper support points for jacks;
jacks are installed in prepared places;
the wooden blockhouse is evenly jacked up, rising above the foundation.

After such a rise of the log house, you can start repairing the base of the house. An already unloaded foundation in damaged areas can be altered, deepened, expanded, strengthened in various ways.

A brick building is incredibly difficult to lift in order to unload a damaged section of its foundation without the threat of destruction. Therefore, it will be necessary to close and fix the resulting through gap, applying a strengthening and tightening belt from the sides.
To strengthen the strip foundation, it is necessary to completely open the damaged section of it, for which it is necessary to dig trenches from the outer and inner sides (from the inner side it is necessary to open the floor in the house) to the entire depth of its foundation.
Broken foundations can be reinforced by placing metal rails over the damaged area. For this:

on both sides of the crack, with an indent from its edge by 20 - 30 cm, drilled with a step of 20 cm, two to three holes with a diameter of about 20 mm are drilled (a total of 4 - 6 holes per one tire);
metal crutches with a length equal to the width of the foundation are inserted into the drilled holes;
to these pins from the inside and outside of the old foundation, they are welded with the trim plate of a channel of size 10 or larger. Two such tires must be installed (top and bottom) or three (one more in the middle).

It will be more reliable to strengthen the strip foundation by adding an additional reinforced reinforced concrete belt to it. For this:

the old damaged foundation is drilled under metal pins from two or more rows on each side of the crack;
pins from a metal rod or reinforcement with a cross section of about 20 mm and a length corresponding to the width of the foundation tape plus the width of the reinforcing monolith are inserted into the drilled holes;
on the free ends of the pins, a reinforcing grid is welded on;
formwork is being mounted;
the prepared reinforcing lattice is poured with concrete in the formwork.

Thus, after pouring, a sealed gap in the foundation receives an additional support area that distributes the load onto itself.

Cracks in the walls of a piled-up building are usually caused by the unintended shrinkage of one or more of the support piles. The localization of the problem is carried out by arranging a strip foundation section designed to strengthen the pile foundation in the subsidence section. To this end:

a technological trench is dug parallel to the sinking wall of the house to the depth of the reinforcing section;
digging under the sagging wall of the building is carried out from the technological trench, bypassing the support piles without violating their position;
at the digging site, a reinforcing grid is arranged, which is connected to 2 - 3 piles of the old foundation;
formwork is mounted on the reinforced area;
the reinforcing lattice of the reinforced section in the formwork is poured with concrete.

The emergence of the question of how to strengthen the foundation of a house if a crack has begun on its wall is a very unpleasant problem for the owners. But this is far from being a reason for despair. Reanimation of the foundation is quite a feasible task. The home craftsman can learn how to repair a crack in the foundation, guided by these tips and tricks.

Do-it-yourself repair and cracks in the foundation of an old wooden country or private house: step-by-step instructions + Video

It is not uncommon for the owners of private houses and cottages to encounter the problem of cracks in the foundation. Cracks can appear for several reasons. Let's take a closer look at them and how to repair the foundation of a private house.

They can be conditionally divided into two: deterioration in the bearing capacity of the soil and deterioration in the bearing capacity of the foundation itself.

In the first case, this can happen due to flooding. When saturated with water, some soils lose their bearing capacity. Also, during flooding, soil erosion can occur. This happens in areas where the soil consists of sandy and sandy loam layers.

Also, subsidence of soil consisting of limestones and marls is possible, if, for some reason, the groundwater has acquired acidic properties, which destroys calcites.

Soil subsidence as a result of mine workings, pumping out of artesian waters, oil and gas production have become very frequent occurrences.

The second reason is the deterioration of the bearing capacity of the foundation itself as a result of factors affecting it, leading to its destruction.

Ground water is one of the factors; ordinary water can cause corrosion of the metal and destruction of the base. Nowadays, acidic and alkaline groundwater is not uncommon, which can destroy the foundation of a house in a few years.

A frequent violation is not observing the depth of the foundation. The foundation laid to a shallower depth than the freezing of the soil is affected by frost heaving of the soil - this is a force that can break the foundation monolith and lead it to cracking.Also, the reason for the destruction of the foundation is often the use of poor quality materials and savings on them. Image - DIY repair of cracks in the foundation

To determine the causes of the destruction of the foundation, specialized firms can be attracted, but the cost of such work will be very high.

Do not despair, there are many ways that will allow you to determine the causes of the destruction of the foundation inexpensively and with acceptable accuracy.

This study is carried out in order to determine whether the crack continues to grow, the rate of increase, the nature of the process.

For this, the so-called beacon markers are used. They are made of gypsum or cement mortar with the addition of gypsum. It is very important that after drying it does not stretch and be brittle enough. It is also important that the mortar is firmly attached to the surface of the foundation, without peeling from it. For this, the base is pre-cleaned.

Having prepared a little composition, it is applied to the crack, the layer thickness is made 3-5 millimeters, ten fifteen centimeters long and three five centimeters high.

Install at least two markers per crack. One marker is placed near the beginning of the opening, the second near the end.

After applying a marker, a thin longitudinal line is made on it; it can be made either with a metal ruler or with a spatula. Markers are numbered. The number and date are recorded in the measurement log.

If the process of opening cracks continues, then the beacon also gets a crack. Making measurements of the crack width at certain intervals and making entries in the measurement log, they make a conclusion about the deformation rate of the foundation, about the part of the house that shrinks. They also make a forecast about further destruction of the foundation.

The second method of work on the study of the foundation is the method of digging pits.

Next to the foundation, a hole is dug one meter long and deep to the base of the foundation (pit), the width is determined by the convenience of digging, taking into account the conditions for the production of slopes to prevent soil collapse, or strengthen the walls with boards.

At least two pits are dug in the most problematic places. The method of digging pits is the most informative. Using this method, it is possible to determine the depth of the foundation, the presence and condition of waterproofing, the material from which the foundation is made, as well as the presence of groundwater.

If there is a presence of groundwater, then it is possible to determine what properties they have. To do this, use ordinary litmus tests, which can be purchased at garden stores.

After determining the research and determining the causes of the destruction of the foundation, they begin to repair the foundation with their own hands.

The cause of the deformation can be eliminated, and the destruction is not significant and only cosmetic repairs may be required.

Also, sometimes the deformation of the foundation is so serious that it will not be possible to repair it with your own hands. Or it will be necessary to repair the foundation, the price of which will be comparable to new construction.

There are two types of flooding: the first is caused by the influx of rain or melt water. The second is the rise in the level of groundwater.

In the first case, it is enough to create a shock barrier directing water past the house, and the construction of a blind area at least 80 centimeters wide.

In the event of a rise in groundwater, it is necessary to carry out dewatering. For this, drainage is done. Drainage is a drainage system made in the form of a circuit with pipes laid in a trench and covered with gravel around the house. Drainage of excess water leads to the storm sewer.

Deformation caused by frost heaving.

This type of deformation occurs when the foundation is laid above the level of soil freezing. The amount of deformation depends on the degree of heaving of the soil. Both significant and small deformations are possible.

To eliminate freezing, it is necessary to insulate the foundation. Insulation is carried out to the bottom of the foundation sole. To do this, a trench is dug around the perimeter of the house, then the foundation is waterproofed, the side wall of the foundation is insulated and covered with screenings or small rubble. A layer of insulation is laid on top of the backfill and the blind area is poured.

In case of significant destruction of the foundation, while eliminating the destructive factors, the foundation is also repaired. Image - DIY repair of cracks in the foundation

One of the most popular methods is considered to be the foundation liner. The essence of the method is to deepen and increase the area of the sole support. It can be implemented in two ways: with partial replacement of masonry and complete replacement.

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.

Further, concreting is carried out, less often rubble laying is performed. The opening and concreting of the grips is carried out on the condition that the expanded grip is protected by the adjacent one.

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 production 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.

Wide clips are not reliable and durable, difficulties also arise during anchoring, the impossibility of transverse through reinforcement leads to the conclusion about the rationality of their use.

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.

The base of the foundation is cleaned of debris. I am digging a trench around the perimeter of the house, the bottom of the trench is covered with rubble.

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.

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. Image - DIY repair of cracks in the foundation

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.

Table. Recommendations for the selection of pit sizes

When in spring the soil begins to thaw from long frosts, cracks and breaks appear on the foundations of many houses, which in the future can cause many problems for the owners. There are many reasons for cracks.And each owner must first find out, as a result of which cracks appeared in the foundation, in order to understand how dangerous they are and whether they can be fixed with their own hands or is it better to entrust the repair to specialists.

Scheme of cracks in a concrete base: 1 - Normal crack, 2 - Inclined crack, 3 - Longitudinal crack.

Cracks can appear in spring due to natural subsidence or heaving of the soil on which the foundation stands. This is especially true for loose soils, such as clay or loam. Water is one of the main reasons for the destruction of the foundation of a house, since concrete constantly absorbs liquid, and when it freezes, it expands the pores of the concrete. When the water begins to thaw, it rushes into the pores enlarged by it and fills them.

This process takes place in the off-season, and in order to avoid it, it is very important for the owners of the house to take care of laying out excellent thermal insulation and a drainage system in advance. Indeed, if this is not done, even the strongest foundation may be destroyed in the future. If surface drainage is improperly performed, water will penetrate under the building. If inaccuracies were made during deep drainage along the perimeter of the house, then there will always be dampness in the basement, which will negatively affect the condition of the base.

If the house was built not by experts, but by the owners themselves, then they could have done many other mistakes. For example, during the pouring of the foundation, use low-grade concrete, improperly mount the formwork or place the reinforcement inside the foundation in a wrong way, they could have laid the foundation above the freezing depth of the soil. They could incorrectly calculate the bearing capacity of both the soil and the foundation itself. The latter circumstance could cause cracks if an attic was added to the house, another floor was erected above it, or the roof of the building was changed to a heavier roof.

Concrete base scheme.

If the construction of the house was carried out by a team of hired workers, the builders themselves could replace the high-quality concrete with a product of lower quality, or they accidentally made some mistake. Another reason for the appearance of cracks on the base is the natural wear and tear of the building due to its long-term operation. There are many reasons for damage to the foundation, and they will be different for each house. How can the owner himself determine what is happening with his construction and what to look for first of all?

To begin with, the owner of the house must carefully examine the foundation or wall around the entire perimeter of the building and pay attention to 2 things: the size of the cracks and their direction. An experienced owner always monitors his home and is able to notice the slightest changes that occur with the building, which means he can even see cracks, thin as hairs. It is another matter if the building is a country house or a country cottage and the owners visit it infrequently. Over the winter, not hairs may appear on the base, but even furrows. The size of a foundation crack does not always indicate the severity of the problem. So, very small hairs may indicate some kind of large-scale trouble, and walls with deep faults can stand for years without much change.

An important indicator of the problem is the direction of the basement fault, it can be vertical or horizontal.

Scheme of increasing the crack resistance of a concrete base.

Horizontal cracks form after winter and indicate concrete shrinkage. They usually appear on new concrete and repeat at approximately equal distances from each other. Shrinkage cracks are small, with an opening of up to 2 mm. If only such damage is found on the basis, the owners are quite capable of eliminating them with their own hands and, having performed simple repairs, breathe a sigh of relief.

However, long and deep faults indicate more serious problems.For example, about the drying out of concrete due to low winter temperatures or about the increased pressure of wet soils on the foundation. If horizontal faults are accompanied by bulges, then the base of the house has shifted or pressure is exerted on the load-bearing wall.

Vertical faults are much more dangerous. It is because of them that the foundation of the house can be destroyed in the future, and at first it is difficult to open a window or door in the room. If the owner found vertical faults, you should not immediately panic and contact a specialist. A small crack in the foundation with even edges can be repaired with your own hands. But a rift with uneven edges, widening downward or upward, is serious, it is better to eliminate it by people who know their business. It is also preferable for specialists to solve the problem by making repairs if there are depressions or bulges on the foundation, if the wall fault goes with a slope, if the cracks are wider than 1.5 cm, and water begins to ooze from the edges of the fault. Image - DIY repair of cracks in the foundation

Repair and waterproofing scheme for cracks in concrete.

In order to understand how the crack that has arisen on the base behaves, whether it has "frozen" in place or is increasing, rapidly or slowly "growing" in width, it is recommended to conduct 2-3 weeks of observation of it. To do this, first, the detected crack should be cleaned of dust or rinsed with water. Then a plate of cement-sand mortar, gypsum or plain paper is applied across the fracture. This plate is also called a lighthouse. Above on the lighthouse indicate the date of the beginning of the observation. If the crack on the foundation is not one, but several, a similar plate is superimposed on each of them. Further, the state of the installed beacon is monitored.

If after a few weeks the plate does not break, then the crack is not enlarging. It appeared not inside the base, but only in its protective concrete layer. In this case, the owner can breathe a sigh of relief and make light repairs. A rupture of the installed beacon indicates that crack opening continues and measures must be taken to prevent it. To find out how quickly the crack grows, you can install several beacon plates along its length. To determine if the fault is lengthening, you need to periodically measure with a ruler. As the crack grows larger, more extensive repairs to the base are needed.

It should be borne in mind that faults can form not only on concrete above the surface of the earth, but also under it, so the owners should definitely dig out the soil under the visible crack and examine the base for damage. If water appears during this process, then it will be necessary to arrange drainage: lay pipes or arrange storm drains.Repairing a foundation with damage no thicker than a hair can be done by hand. To do this, you must first clean the crack from exfoliated particles and dust, blow it with the air of a building hair dryer. Then the cracks are treated with a special primer designed for concrete. After the primer has dried, glue-sealant is applied to them with a thin brush.If the size of the cracks is from 1.5 to 5 mm, then they are sealed in a different way. He will need a cement mixture, water, a chisel, a trowel, a pump with a hose, a damp cloth, gloves and goggles. Image - DIY repair of cracks in the foundation

Repair scheme for cracks in concrete.

The main material for sealing cracks are mixtures specially created for this purpose, to which you need to add water to get a pasty mass. These mixtures dry quite quickly, therefore, after combining them with water, you should immediately begin to seal the cracks, which should already be prepared for repair. From the holes formed, crumbs must be removed with a chisel, the cracks themselves must be moistened with water (it is better to use a hose for this) and wait until they dry completely.The paste is used to fill the crack with a trowel, the mass should protrude to the surface in the form of a pebble. After the mortar has set, the concrete surface is smoothed out. Then you need to cover this place with a cloth and keep it moist for several days.

Another material used to repair cracks is epoxy resin. For work, you will need a hair dryer, a metal brush, a medical syringe, several tubes of epoxy resin with a hardener, a stick for stirring the solution, a cardboard box and a spatula. Work must be carried out with gloves.

Before sealing, the surface of the crack must also be prepared in advance: cleaned with a metal brush from dust and debris and blown out with a construction hairdryer. When the surface is completely dry, you can fill it with resin. First, mix the hardener and liquid resin on a piece of cardboard with a thin stick. Then the syringe is quickly filled with the resulting solution. Next, the solution is squeezed out of the syringe into the prepared crack. With the help of a spatula, excess bauxite is removed from the concrete surface before it has time to harden.

Video (click to play).

More serious cracks are not easy to repair. They arise as a result of subsidence of the base and require, for example, measures such as additional reinforcement of the outer contour of the foundation and the creation of new supports next to the existing concrete supports, fastening the base with brackets, etc. Such a cardinal repair can only be performed by a construction team. The appearance of cracks in the foundation should not be ignored, it should be eliminated in a timely manner, because a strong and reliable foundation is the key to the long life of any home.