No matter how solid the structure is, due to the effect of pressure and precipitation on it, over time, the foundation collapses or subsides. However, each owner of a private house can independently repair or reconstruct the foundation.
Features of foundation repair, depending on the problem
The service life of the base of the house directly depends on the quality of its installation and the materials that were used for this.
Survey of foundations
When a crack appears, it is imperative to determine whether it increases. For this, so-called markers are installed. In order to check if the crack is progressing, it is necessary to stick a paper tape across it and leave it for 10 days. If the tape remains intact, then the crack can be filled with fragments of bricks, and then concreted. If it became clear that the development of the crack is progressing, then it is necessary to come to grips with repairing the foundation or replacing it in the case when reconstruction is impossible.
As a beacon, you can use both a gypsum solution and a ready-made mixture for plaster. The composition should not be plastic after hardening, it should be as fragile and susceptible to mechanical damage. After preparation of the mixture, it must be applied to the crack with a layer of 3-5 mm, 100-120 mm long. You need to apply across the crack, and in such a way that it is approximately in the middle of the marker.
For greater accuracy of the result of markers on the foundation crack, there should be at least two
There is another way to survey the foundation. Although it is more time consuming, it is more informative. The method consists in preparing pits. A pit is a pit, the depth of which coincides with the height of the foundation. The length of each pit (there should be at least two) is 100 cm. The width is selected strictly individually. After the pit has been dug, it is recommended to strengthen its walls with unedged boards. This measure is needed to prevent land collapse.
The size of the pit depends on the height of the foundation and the size of the person who will carry out the work.
It is recommended to make pits only in problem areas. This will allow you to gain access to the walls of the foundation and determine the quality of the installation, the materials used, and also give information about the depth of the groundwater (they can be checked for acidity or alkalinity).
This method allows you to start repair work almost immediately.
Possible causes of destruction
At the moment, there are three main reasons that provoke the destruction of the foundation of varying degrees:
- human activity;
- shortcomings in the very process of work, careless attitude to installation, violation of technology, use of cheap low-quality materials;
- the influence of external natural factors (rain, frequent temperature drops, rising groundwater).
Most often, it is water that becomes the main reason for the collapse of the base of the house. Ground water or tap water can enter the ground under the building, while it is in winter period freeze slightly, increase in volume, and in a warm period they cause the destruction of the base of the house.
The cause of the destruction of the foundation can be groundwater or a change in load.
Similar processes occur during seasonal heaving of the soil. It also happens that the foundation as a result rises by more than 10 cm. However, the most serious problem for the foundation of any house is soil subsidence.
Signs of destruction
Each owner of the house can independently determine that the foundation of his house is beginning to collapse. Cracks or depressions appear. But remember that not every crack that appears when the foundation shrinks is a sign of failure. Sometimes, just a cosmetic repair is enough to solve the problem.
Signs of destruction can be overt and subtle. Among the main ones are:
- thin cracks that can appear not only on the basement, but also on the walls;
- violations of external or internal decoration in the area of destruction;
- visible deformations of the floor covering, possible failures;
- collapse of the building, which at the first stage of the destruction of the foundation can be only partial;
- deformation of individual sections of the foundation;
- sinkholes next to the damaged foundation.
To identify hidden signs of destruction, it is necessary to conduct a special examination, for which it is better to invite specialists with equipment.
DIY repair: step by step instructions
The reconstruction process depends on the cause of the problem as well as the nature of the problem itself.
Cracked the foundation
To choose the best option strengthening the cracked foundation, it is recommended to determine the nature of the destruction.
If a crack appears along the entire perimeter of the base and its cause is increased soil moisture or a change in external load, the repair process should proceed as follows:
- Around the house, along all the walls, you need to dig a trench.
- Clean the surface of the foundation from old plaster, dirt.
- Install a metal grate at some distance from the foundation. For this, it is recommended to use metal anchors, which must be driven into the plinth and base.
- Concrete this structure, carefully ramming the mortar.
If the foundation was made of rubble, monolithic concrete, soil concrete, then reinforced concrete reinforced cage is used for reinforcement. Its anchors must be connected to the old base. This will reduce the load slightly.
A problematic crack is one that grows in size.
If weakened areas are found, the bearing capacity of the base must be increased. This can be done by laying a new one along the old foundation and connecting them with anchors.
The foundation sank
This problem usually occurs with owners of brick houses with a similar base. It is recommended that a crack progression test be performed before repairs are made. If the result is positive, then the repair is carried out as follows:
The repair of a monolithic foundation can be carried out in the same way. True, this will require more effort.
Foundation problems after winter
After thawing, especially if the winter was snowy, cracks and other deformations may appear. In this case, it is necessary to conduct a thorough study of the foundation, to determine whether the cracks are superficial or deep, which caused such destruction. In most cases, a drainage system will need to be installed. These can be drainage pipes, storm drains, wells.
After winter, the foundation can collapse if in the fall it is saturated with moisture and froze
You can independently perform a blind area. In particular, you need to expand it, provide a greater angle of inclination, while using heat-insulating material, ideally extruded polystyrene foam. Remember that the ingress of moisture onto the blind area is detrimental to the foundation itself, since it leads to its moistening. Therefore, it is recommended to ensure that all moisture is discharged into the storm sewer.
If there are problems with the foundation after winter, the gunning method can be used to strengthen the foundation:
The foundation was deformed
It may happen that the foundation is deformed or burst. You can correct this situation yourself:
Reinforcement can also be used for reconstruction.
There are two ways to reconstruct a foundation if it starts to crumble. The first is associated with a complete replacement of the base. However, this is done in parts, with special attention paid to the corners and areas under the windows, because these are the weakest parts of the foundation. Ideally suited for this type of reconstruction is the so-called method of gradual casting from reinforced concrete. In this case, reinforcement binding is mandatory.
The second reconstruction method is the use of clips. In advance, you need to take care of the availability of the following materials:
- primer;
- anchors;
- fittings;
- clips;
- cement-sand mortar (you can take a ready-made one or prepare it yourself).
If the foundation is crumbling, then a complete replacement may be required.
The principle of this method is to strengthen the base of the house by using concrete or reinforced concrete clips in order to protect against further destruction. In this case, everything must be done as carefully as possible, since such a structure is rather fragile. This method is especially relevant for the reconstruction of the base of a brick house. When performing work, the following instructions must be observed:
Don't forget about waterproofing. Otherwise, repeated destruction of the building is possible.
Home foundation repair
The issue of reconstruction of the foundation of a private house is especially relevant, since this structure is much more solid than outbuildings, which means that it is necessary to approach the issue of repair more responsibly.
Replacing the foundation
Replacement of the base is carried out when its bearing capacity has decreased. Also, such an extreme measure is used when it is necessary to increase the life of the structure.
Hydraulic jacks are usually used to replace the foundation. The preparatory stage consists in the selection of the necessary tools and materials:
- jacks (you can rent them);
- steel scrap;
- wedges;
- sledgehammers;
- chocks or bricks as supports;
- steel plate 5 cm thick as a base for the jack.
The replacement process itself consists of several stages:
You can only raise the house by 2 cm at a time
How to level the foundation
A columnar foundation has one common problem - the pillars begin to slope. This happens, as a rule, due to excessive heaving of the soil or violation of the installation technology. The main method of repair is to replace old supports with new ones. It will no longer be possible to return the old supports to their previous state.
The main problem of the columnar foundation is that the pillars begin to look askew
The repair process is as follows:
Video: repair of a columnar foundation
Repair of brick foundations
Before proceeding directly to the repair, it is necessary to clean the foundation from the plaster. This will allow you to assess the severity of the damage, as well as the possibility of reconstruction with your own hands. If the damage is quite serious, then:
- It is necessary to dig a trench and then fix the metal mesh with anchors.
- Next, mount the formwork and pour the concrete solution. The formwork can only be removed when the concrete has hardened thoroughly.
- After that, the trench can be filled up, tamping the ground well.
If the damage to the brick base is minor, then the repair consists in replacing the damaged areas and restoring the blind area. In this case, you need to carefully monitor that the old and new sections of the foundation are in a bundle.
Additionally, it may be necessary to install a reinforced concrete frame, which, in turn, is attached to the support with through anchors.
Video: repairing the foundation of a brick house
Repair of the screw foundation
As such, the repair of the screw base is not carried out. If there are any problems with it, the piles are replaced. They do it according to a certain plan:
How to strengthen the foundation
There are several ways to strengthen your foundation. The most popular is the laying of a new foundation along the old one. You can do this work yourself:
Repair of the foundation of a wooden house
There are some features of repairing the foundation of a wooden house (or bathhouse). It is this part of the building that is most vulnerable. The whole process takes place in several stages:
When carrying out repair work, it is necessary to observe safety measures. First of all, it is strictly forbidden to climb under the raised structure, no matter how strongly you are convinced of the reliability of the jacks. It is also not recommended to leave the structure only on jacks; it is better to install additional supports.
Video: how to replace a crumbling foundation under a wooden house
A house in a summer cottage is perceived by many owners as something temporary - if only there was a place to hide from the rain or the midday sun. Accordingly, they approach the choice of building materials from the point of view of maximum savings.
But the years go by, households continue to use the dacha, and the "roof over their heads" begins to slowly collapse.
Moreover, this process begins from the very foundation of the building.
And the amateur gardener has to retrain as builders and take on the country house.
If the walls of the house are lined with bricks, then you will have to limit yourself to measures to strengthen its foundation ().
Strengthening the strip foundation
The repair of a country house is carried out as follows:
- a trench with a depth of about 500 mm is dug along the perimeter of the tape;
- the exposed surface of the foundation tape is thoroughly cleaned of dirt, not forgetting to remove the plaster and paint from the base;
- holes are drilled along the length of the damaged section of the foundation with a step of 600-1200 mm, into which the anchors are then screwed in (or pieces of reinforcement are tightly hammered). There must be at least three rows of such holes vertically;
- a reinforcing mesh made of rods with a diameter of 10-14 mm is welded to the anchors;
- all cavities found in the monolith are filled with concrete mortar. If they have a large volume, this operation should be carried out with the installation of formwork panels. In the presence of serious damage at a distance of 150 mm from the side surface of the tape, a full-fledged one is installed and poured with concrete.
After the concrete dries out, the foundation is waterproofed, and the trench is filled up with layer-by-layer soil compaction.
Strengthening the supports of the columnar foundation
The scope of work to strengthen the columnar supports practically does not differ from the above.
A video about repairing the foundation of a country house with your own hands.
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 provides even distribution loads created by the structure erected on top of it, and also protects the building from forces and stresses arising in the soil.
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.
The list of reasons that can lead to deformation of the foundation is given in the table.
Table. Why is the foundation crumbling
| Causes | Description |
|---|---|
| This can occur as a result of erosion and flooding of the soil - it is saturated with moisture, which leads to the loss of the necessary bearing capacity. The reason lies in the peculiarities of some types of soils, which lose their bearing capacity when the humidity rises to a certain level. | |
| The reason, again, lies in flushing, but the mechanism for the development of the problem is somewhat different. In this case, the bearing capacity of the soil remains at the same level, but some of the soil is washed out from under the support platform, which leads to the appearance of voids. Sandy and sandy loam varieties of soils are most susceptible to such unfavorable changes. | |
| The presence of marls and limestones in the soil adversely affects the condition of calcites, which are the main elements of concrete. Upon contact with these, the destruction of the structure of the material at the molecular level occurs. | |
| "Underworking" refers to underground voids formed in the areas of mine workings, oil production, large-scale pumping of ground water, etc. | |
| Contact with water will corrode the materials used in the fabrication of the substructure. As a result, even if the indicators of the bearing capacity of the soil remain at a normal level, the foundation may collapse. Especially dangerous are waters with alkaline and acidic inclusions. | |
| The list of those includes many positions. The most common deviation from the norm is a violation of the requirements for the depth of the support structure, justified by the developer's desire to save money on earthworks and concreting. The second popular violation is the use of materials for concreting that are not intended for this. For example, in the era of a shortage of high-quality materials, many developers erected foundations using silicate bricks, slag concrete and other similar products, the strength, reliability and durability of which are in many ways inferior to correctly performed reinforced concrete pouring. |
The table provides a list of the most common defects in support foundations.
Table. Foundations defects
| Defects | Description |
|---|---|
| The upper part of the support of such a building is operated in more severe conditions compared to the timber of the walls, which is why it ages and collapses much faster. | |
| The problem is typical mainly for troubled soils with a high degree of frost heaving. | |
| Most often, foundations sink due to violation of building codes and technologies at the stage of construction of the support structure. | |
| Prolonged contact of a concrete support with open air, precipitation and other atmospheric phenomena can lead to the destruction of the foundation. The situation is especially aggravated in the case of the construction pouring in the winter season. That is why it is necessary either to immediately continue construction after the foundation has set the required strength (according to GOST - 28 days), or to build a shelter that protects the structure from atmospheric influences. | |
| Incorrect laying of blocks often leads to the destruction of the supporting structure - individual blocks simply crack and fall out, which does not in the best way affect the strength of the foundation. | |
| They arise for a variety of reasons. The most common ones were given earlier. | |
| It occurs mainly due to improper arrangement of piles, especially on soils that are highly prone to heaving. The problem usually appears within the first year after the support system has been erected. | |
| Occur in the following cases: - when providing insufficient support area of the foundation base; - in case of emergency soaking of the surrounding soil; - under excessive load on the supporting structure; - when erecting a foundation in highly compressible soil types. |
|
| The following reasons lead to the occurrence of such deformations: - decrease in the strength of the foundation wall masonry below the permissible level; - excessive loading of the surface next to the building; - frost heaving of the soil, exceeding the permissible values. |
|
| The reasons for the appearance of this defect are as follows: - incorrect dressing of the masonry or lack thereof; - a decrease in the strength indicators of masonry as a result of prolonged operation, frequent soaking, various aggressive influences, etc.; - overloading of the support structure. |
|
| Occurs when: - the impact of various aggressive factors on the surface of the supporting structure; - lack of waterproofing or its insufficiently high-quality arrangement. |
|
| This defect occurs mainly under the influence of excessive forces of frost heaving of the soil. Risks become especially high if the foundation was laid in violation of the technology. | |
| Such cracks appear mainly when the foundation is overloaded and / or when reinforcement of insufficient large diameter is used when it is laid. |
Necessary research before starting repairs
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.
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.
First study. 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.
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.
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.
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.
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.
Plaster prices
plaster
Second study. Preparation of pits
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.
The dependence of the pit dimensions on the features of the foundation is presented in the table.
Pits are created in the most problematic areas with the most pronounced deformations. Thanks to such a pit, you can access the supporting structure and see how deep it is laid, what it is made of (if the building was not built by the real owner), in what condition it arrives, how high-quality the existing waterproofing is. Additionally, you can get information about the depth of groundwater. The latter will appear after 1-2 days.
If you wish, you can test the groundwater for acidity and alkalinity. To do this, pre-purchase the appropriate tests in stores specializing in the sale of a variety of agricultural chemicals. Litmus paper works best.
After completing the specified diagnostic measures, you can proceed directly to the repair work.
Foundation repair: instructions and important notes
You are invited to familiarize yourself with the procedure for carrying out repair activities that can be performed on your own or with minimal involvement of outside labor and special devices.
Important! The above cases are the most common. If you follow the building codes and regulations, preparation for the repair of the foundation begins with the creation of a project for the upcoming work, including information about the existing deformations and possible ways their elimination in a specific case.
In most situations, for a successful foundation repair, especially if a wooden bath is installed on top of it, the structure must be lifted. This is done in different ways (with a crane, ropes stretched under the building, etc.), but the best method is the one that involves the use of jacks.
Ideally, jacks should be installed along the entire perimeter of the structure - this will ensure an even distribution of loads and minimize the risk of destruction of building elements. You will need at least 2-3 jacks - in this case, you will gradually move them around the perimeter of the building, replacing them with metal support frames, but it will take more time to complete the work in such conditions. The recommended lifting capacity of the jack is 5 tons.
Prices for jacks with a lifting capacity of 5 tons or more
jacks 5t 6t 7t 8t 9t 10t
A fairly common problem - the pillars began to deviate from the vertical. This happens mainly under the influence of frost heaving forces or due to violations of the technology of pouring pillars.
Important! Before starting work, read the information on the methods of tying reinforcement for the foundation and the instructions for preparing the mortar and constructing the formwork for - the necessary information was given earlier in the relevant publications, therefore it is not described again.
In this case, the repair is reduced to replacing the rickety pillars with new correct supports.
The instructions are given in the table.
Table. Column foundation repair
| Stage of work | Description |
|---|---|
| First of all, it is necessary to install supports, which will temporarily take over the functions of the remote support pillars. The image shows a support made of a bar with a section corresponding (better - exceeding) the dimensions of the concrete support post. The bottom wood pad is needed to create a larger footprint and better load distribution. A similar wooden platform is recommended between the bottom of the building and the top of the support. The installation of a wooden support is carried out at a minimum distance from the foundation post to be replaced, with the expectation that in the future it will be convenient to perform the necessary working manipulations. If you have jacks, you can use them instead of wooden supports - it's even more convenient. |
|
| A weak support is being dismantled, up to a sand and gravel cushion. Important! If it turns out that the pillars were mowed due to their insufficient depth, the presented manual additionally includes the stages of excavating the existing sand and gravel backfill, deepening the pits and re-arranging the cushion. To break up concrete, it is most convenient to use a hammer drill. The work is dusty enough, do not forget to wear safety glasses and a respirator. The reinforcement cage must also be dismantled. You are unlikely to succeed in preserving its integrity and ideally cleaning it from hardened concrete, so you can make your work easier by armed with a grinder, sawing the rods into separate elements and removing them from the hole intended for pouring the pillar. |
|
| A new reinforcing support is being built. For greater reliability, assemble it from reinforcement with a diameter of 2 cm. The maximum cell size is 20x20 cm. The height of the frame is selected in accordance with the height of the concrete support. You can see the required number of rods and the principle of their connection in the image. | |
| Install a reinforcing frame in the pit. | |
| Pour the first ball of concrete so that it covers the sole of the reinforcing frame by 5-10 cm. Leave the fill for about a day (preferably 2-3 days) for the concrete to gain its initial strength. | |
| Install prefabricated timber plank formwork and pour concrete to the top. It is advisable not to remove the formwork until the complete set of concrete of the required strength. According to GOST, under normal conditions (above-zero temperature), this takes 28 days. Leave the support for the specified time. All rickety pillars are repaired in the same way. |
In addition, we offer you an improved version of the above technology, which involves the arrangement of a grillage - a monolithic reinforced concrete tape that connects the support pillars into a single system and provides a much more efficient performance of the key functions of the foundation structure. The only drawback of the technology is that you will have to work with all the posts, replacing them with less high supports in order to get a place for filling the grillage.
First, you do everything in the same way as in the above technology, but the height of the part of the post protruding above the ground (and therefore of the formwork) is reduced by the height of the grillage. The recommended overall characteristics of the grillage are as follows: height - at least 300 mm, width - at least 400 mm.
The order of further actions is presented in the table.
Table. Continuation of the repair of the columnar foundation
| Stage of work | Description |
|---|---|
| Assemble the formwork from high-quality boards with a thickness of 4-5 cm. For fastening individual elements, it is preferable to use bolts - after the concrete has hardened, it will be much easier to unscrew them than to pull the nails for the subsequent dismantling of the formwork. | |
| Steel rods with a diameter of 1.2-1.4 cm are suitable for reinforcement. The reinforcement is laid in two rows. The diagram is shown in the image. | |
| Fit the side panels of the formwork. More detailed recommendations on the correct conduct of this stage of work, you can get in the previously mentioned publication. Leave gaps for pouring concrete. | |
| Pour concrete into the grillage formwork in even horizontal layers. |
Now all that remains is to wait at least a month until the concrete gains the required strength. Then dismantle the formwork. As a result, you will receive a reliable, correct and durable support structure.
Subsidence foundation repair
This problem is most often encountered by owners of buildings built on brick or rubble support bases. How to make sure there are growing cracks (using plaster markers) was discussed earlier.
After completing the preliminary diagnostic measures, get to work. Let's say right away that it is possible to repair a rubble / brick foundation by replacing destroyed sections of masonry, but it is impractical - since the support has begun to crack now, the problem will surely arise in the future. The best option repair in a similar situation is the replacement of the prefabricated foundation with a monolithic concrete slab.
Pre-dig a trench around the perimeter of the structure to get to the bottom of the support base.
Table. Repair of rubble / brick foundations
| Stage of work | Description |
|---|---|
| Destroy a 50-100 cm wide section of masonry for the subsequent installation of the jack. Use a hammer drill, sledgehammer and accompanying auxiliary tools for destruction. It is better if there are several jacks available, so that you can make similar openings with about a meter step around the perimeter of the structure and fix the entire building on the jacks at once. Important! When using jacks, the structure is lifted gradually, up to a maximum of 100 mm in one pass. Haste in this case can lead to irreversible violation of the geometry of the building. |
|
| As noted, it is better to install the jack on a support - this will increase the area and the efficiency of load distribution. The support can be a pre-poured or ready-made concrete slab, building block, etc. To increase the contact area between top jack and the "bottom" of the house, lay between them a metal plate with a thickness of 1 cm and a length of about half the width of the selected opening. With the fixtures in place, raise the structure over the old support base and secure the position with jacks. Useful advice! Before lifting a building on jacks, it is highly advisable to temporarily dismantle windows and doors, because they may not pass such a test. Also, items of internal furnishings should be taken out of the bath and, if possible, a stove in order to maximize the ease of construction. |
|
| Assemble support boxes from at least 2 cm (in diameter) reinforcement. The structure of these is shown in the image. Select the height of the box so that it goes into the opening between the base and the structure and is rigidly fixed there. The recommended support width is approximately half the width of the selected opening, i.e. 25-50 cm. In the image shown, the support stands on the same platform as the jack. We will do the other way, installing the support structures directly on the previously equipped rubble backfill. It is only necessary to additionally carefully seal it, because the density could have decreased during the previous operation of the building, and leveled horizontally as much as possible. Work in a similar manner until you have installed metal supports around the perimeter of the entire building. It is recommended to keep the step between the props within 100 cm. |
|
| Install the inner wall of the formwork. This image shows the bottom support layer of compacted sand and gravel and metal box supports. Recommendations for the installation of the formwork were given earlier. |
|
| The reinforcement scheme is shown in the image. Run a similar row of fittings along the top. For work, use rods with a diameter of 14 mm. | |
| The outer formwork wall is mounted and concrete is poured. |
Useful advice! In a similar manner, it is possible to replace not only the prefabricated rubble / brick foundation, but also the monolithic strip support base. Everything is done in the same order, only to destroy the concrete tape and remove the old reinforcing layer will have to make much more effort than replacing the crumbling brick / rubble support.
As noted, one of the most common problems of log baths is the premature failure of the lower rims, which often begin to rot much faster than the material for making the walls of the building.
Pre-dig several pits and assess the condition of the support structure from sole to top. If there is significant damage to the foundation, repair it according to one of the instructions above. If everything is normal directly with the base and only the lower rims are damaged, work in the sequence shown in the table.
Table. Repair of the basement of a bath from a bar / log house
| Stage of work | Description |
|---|---|
| Armed with a chainsaw or other suitable tool, prepare openings in the lower rims for the subsequent installation of jacks. Select the width of the openings so that it is convenient to install / remove jacks. The distance between the openings is up to 150 cm. |
|
| Place the jacks in the prepared openings. Lift the bath above the lower rims and fix the jacks in one position. Important! The structure should not be lifted jerkily or too quickly - there is a high risk of irreversible displacement of the walls. First raise one wall / corner by a maximum of 100mm, then move to the opposite wall / corner and do the same. In a similar order, gradually raise the entire building. |
|
| Having installed the jacks, cut out the remaining material for making the lower rims. As an example, work with one building wall is shown. With the rest of the walls, everything is done in the same way. | |
| Install metal supports and remove jacks. Recommendations for assembling boxes are similar to the previous instructions. The optimal arrangement of the supports is shown in the image. | |
| Everything is done in the same way as in the previous tutorial. | |
| Recommendations are similar to the previously reviewed instructions. | |
| Pour concrete, give it at least a month to build strength and dismantle the formwork. Your bath now stands on a solid, sturdy and durable support base. You can forget about the problem of rotted lower rims forever. |
The following foundation repair instructions are relevant for the most common cases of failure of support structures. As noted, it must be remembered that each situation is individual and the foundations of two identical buildings can undergo completely different changes and deformations.
If you wish, you can familiarize yourself with information on more complex professional methods of strengthening and reconstruction of foundations, involving the use of special equipment and chemicals. Information on this score was presented in detail by O. A. Korobova in her book “Strengthening the Foundations and Reconstruction of Foundations”.
O.A. KOROBOVA. STRENGTHENING OF FOUNDATIONS AND RECONSTRUCTION OF FOUNDATIONS. Download file
Video - DIY foundation repair
You can determine whether the foundation needs repairs by throwing only one glance at it. The fact that the days of the founding of the house are already numbered are indicated by the distortion of the building, cracks in the walls and the subsidence of the house. It is impossible to insure a building against such deformations, because over time, the foundation materials are destroyed. Therefore, one day the hour comes when the owners of a wooden house have to decide what kind of repairs to do - partial or complete.
Conditions for partial and major repairs
In order to find out the degree of damage to the foundation and determine the necessary measures for its restoration, you need to carefully study the current state of the foundation and identify characteristic defects that can affect the strength and integrity of the building or its individual elements.
If cracks appear on the foundation, then you need to think about the need to repair it.
The foundation is restored fragmentarily if it has dropped below, but has not begun to collapse. A complete repair is used when cracks and other damage are detected.
The decision on which basis to replace a completely damaged structure is made, taking into account the type of soil, terrain and the type of foundation originally created.
If the foundation of the house has sunk into the ground, it's time to repair it.
With a strip base, they often do the following: the destroyed zones are dismantled and the structure along the entire perimeter is reinforced. In case of serious destruction, the foundation strips are decided to completely replace it.
In case of serious defects in the strip base of the house, it makes sense to think about its complete replacement.
Repair of the columnar base is almost always carried out completely: all old building pillars are replaced with new ones. For this, the house is raised to the height of the posts with the help of jacks. New reliable supports are fixed on reinforced concrete cushions.
The columnar foundation is most often completely replaced with a new one.
A foundation made of wood, which has already been spoiled a little by the fungus, is usually replaced with a strip or columnar structure. To do this, the building is raised to a certain level and concrete blocks or bricks are substituted under it.
Strengthening the foundation of a house made of wood
When repairing a foundation, it makes sense to immediately reinforce it. This can be done if you are confident in the stability of the soil, which is below the level of the foundation of your house. Strengthening the structure under the building may also be required in the case when it is planned to make another floor in the house, but there is a suspicion that the base installed earlier will not withstand the increased load.
There are two ways to strengthen the foundation, depending on the load that it has to withstand
Instructions for strengthening the tape structure
To make the foundation more durable, perform the following work:
- A trench is dug along the perimeter of the base. The hole must be wide, otherwise it will be inconvenient to work. In addition, one must take into account that the new foundation will become more powerful.
- The soil is cleaned from the dug foundation. To do this, use a metal brush.
The trench must be wide enough to be comfortable to work in.
- Holes are made in the old base with a drill. It is important that their diameter exceeds the thickness of the purchased reinforcing rods by no more than 1 mm. In this case, the metal elements will be installed reliably and without gaps.
- Reinforcement rods are inserted into the drilled holes with a hammer. They will help tie the new foundation to the old one.
Reinforcement rods are driven into the drilled holes, to which a vertical grid is attached
- The next metal elements are welded to the hammered rods, forming a reinforced belt. It is better to solder the fittings with the rods already installed in only a few places. For the most part, it is wiser to wire the metal elements to avoid deformation of the reinforcement belt during the pouring and hardening of the concrete.
The reinforcing frame will firmly connect the old foundation with the reinforcing concrete structure
- The formwork is installed and filled with concrete. After waiting for the solution to harden, the structure of the boards is dismantled. For several days, the new foundation is not touched, so that it is even more solidified.
A formwork is installed around the reinforcing cage and concrete is poured into it. After the reinforcing layer has hardened, the formwork is removed
- The created base is covered with a waterproofing material. A sloped asphalt strip is created around the foundation.
Thanks to the reinforcement, the weight of the wooden structure is distributed over a larger area. This method allows you to stop subsidence and destruction of the house.
Video: how to strengthen the strip foundation
Replacing the base under a timber building
The method of replacing the base depends on its type.
Replacing the strip foundation
Overhaul of the base in the form of a tape is carried out in stages:
- In order to reduce the pressure on the base, furniture is removed from the house, the floors are dismantled, and the stove is dismantled. Only heating equipment standing on a separate concrete site is not dismantled.
- The structure is slightly raised. If the house is small, then its level in relation to the ground is changed with the help of a kind of lever for lifting weights - a beam of 8x8 cm in size, wound up at the corner of the building. A log will serve as a support for him. For heavy construction, it is better to choose thicker lumber. The wooden structure is raised by applying pressure to the timber.
The house is lifted on jacks and temporary supports are placed under it.
- A trench is dug around the house or only in areas where it is necessary to raise a wooden building.
- A jack is put under the old foundation. There may be several mechanisms for raising a building. The number of jacks is determined by their carrying capacity and the weight of the house. Mechanisms can only be installed in areas where there is no damage.
- With the help of a jack, the house is slowly raised to the desired level. It is important to rise evenly above the ground. Since there is a risk of unsuccessful installation of the jack, it is advisable to play it safe - put wooden wedges between the structure and the base cushion.
The house is lifted evenly with several jacks. For insurance, wooden blocks are placed under the load-bearing beams.
- The lower crown of the raised wooden structure is pulled together with a steel hoop or hammered in with strong boards. This will protect the home's overloaded lower beams from damage.
- The house is freed from the former foundation to the very surface of the earth. If you are not ready to spend a lot on repairing the base, then you can disassemble the structure partially - remove only the destroyed areas.
A hammer drill is used to destroy the old foundation.
- Under the reconstructed base of the house, a pillow is made of a sand-cement mixture. Supports made of concrete or bricks are placed in the corners of the building. You can use piles instead. Thanks to the installation of supports, the size of which must correspond to the height of the base being built, in the future the base will be able to withstand increased pressure.
- A reinforcing belt is constructed, which is necessary to strengthen the base. Elements of a metal structure are connected not by welding, but by wire.
- Formwork is hammered from the boards. The finished structure is filled with concrete.
Formwork with a reinforcing frame inside is reinforced with side supports and poured with concrete
- After 3 days, the concrete hardens, so the formwork is removed, but further work is not yet carried out, waiting for the foundation to harden.
- A few days after dismantling the formwork, the new base is covered with a waterproofing sheet, for example, roofing material.
A few days after removing the formwork, the foundation is covered with waterproofing material.
- The house is lowered, proceeding as slowly as during the raising of the building. The front side of the base is covered with waterproofing and cladding materials. A blind area is made around the house, which will not allow rainwater to seep into the base.
Video: how to repair a tape concrete base
Repair of support pillars
To replace the columnar foundation, proceed as follows:
If it is necessary to replace only a few pillars, they act differently: in the area where they are located, undermines are made, pipes are immersed in them and poured with concrete. The old supports are dismantled after the solution has hardened.
Video: replacing the columnar foundation with your own hands
Converting a foundation from rubble or brick to a monolith
Since the brick foundation is characterized by increased fragility, it is more expedient to replace it with a concrete base.
In order to build a concrete foundation in place of a brick or rubble base, perform the following steps:
Video: brick foundation repair
DIY wooden house foundation repair
Wooden foundations are mostly made from pine or larch. A structure made of wood always requires a complete replacement, since over time it is completely covered with fungus and decays. The replacement of old elements of such a base with new ones is carried out as follows:
The damaged foundation of a dilapidated wooden house can be repaired. To do this, you need to gain the necessary knowledge and choose a repair or replacement technology. Reconstruction of the base of the house can be done with your own hands, if there is a desire and at least a little experience in the production of construction work.
