How to level the unevenness of the foundation after pouring. How to level the foundation after pouring

Everyone knows that a solid foundation is required for the construction of a building. That is why the highest requirements are placed on the foundation. Therefore, many are interested in ways to level the foundation after pouring. Experts will tell you how to level the foundation.
The foundation for the house, made of concrete, should be as even as possible. Before pouring the tape base, it is necessary to cover the finished ditch with gravel and pitch, which will become an air cushion. Many believe that during this period of construction, you should not pay attention to evenness. But it's not. It is necessary to make both the ditch and the layer under the solution even. The air cushion is covered with a thickness of up to 60 cm. The indicators depend on the composition of the soil and the size of the building being erected.
The foundation must be level on all sides. You can achieve maximum accuracy if you use even and strong formwork for pouring. The exposed frame will allow you to create the required height and width of the base.
It is also worth remembering that roofing material or other waterproofing material is mounted on a completely flat surface. An uneven foundation contributes to a leaky fit of the material, which in turn leads to early destruction of the foundation.

Elimination of error

You can make the foundation even using a special level. To carry out such activities, it is necessary to designate the extreme points of the foundation; it is impossible to go beyond in any way. With the help of a special device, it is especially easy to determine the horizontalness of the foundation. With it, you can check all slopes and identify inconsistencies.
To level the already finished foundation, it is necessary to re-level and level the surface additionally. The device must be set at the zero point. The tested area must have the same parameters.
You can only level the base, the bottom can no longer be leveled. That is why it is impossible to save materials on a pillow in any way. It must be laid in accordance with regulatory requirements.
According to the requirements, the depth of laying the foundation should be at least 1 m. This applies to pouring the foundation of an area with severe winters. If the ground freezes from 3 m, then it is simply impractical to mount a shallow foundation. When the soil freezes at 1 m, the height of the foundation will be 0.5 m.

Leveling the sides of the base

Alignment of side irregularities depends on the degree of skew. In case of minor discrepancies, it is necessary to fix the chain-link mesh with dowels or staples. On such a basis it is worth applying a plaster mixture, thereby leveling the surface and eliminating inaccuracies.
If the errors are very large and the foundation is too curved, it is recommended to re-install the formwork and top up the foundation. In the case when the misalignment is more than 5 cm, it is necessary to install a reinforcing belt. An additional element will not only strengthen the foundation, but also provide better adhesion of the liquid mortar to the hardened concrete.

Leveling the top of the foundation

Leveling the foundation along the horizon is the most important event. After all, the top is a place for direct fixation of the waterproofing layer and masonry walls. That is why irregularities on the surface of the foundation are simply unacceptable, since on such a basis it is almost impossible to lay the first row of bricks correctly.
To level the frozen foundation, re-installation of the formwork will be required. When performing such a task, the use of a level is necessary. Also, using a level, it is necessary to determine the highest point of the base. It is this place that will become the point of settlement.
After the formwork is installed and all calculations are made, it is necessary to prepare a mortar, which should be much thinner than standard concrete.
To perform work on leveling the horizontal surface of the foundation, the following are used:

• fresh cement mortar of a thin consistency;
• building level for special purposes;
• formwork made of boards;
• mesh for reinforcement;
• tools to get the job done.

Aligning a horizontal foundation is, of course, not difficult, but it is better when the alignment occurs initially and no topping up is required. After all, only a holistic foundation can be the strongest and most reliable. That is why the basement of the foundation must be created carefully and accurately.

Foundation pouring rules

In order to properly fill the base, you must:

• mount and install formwork;
• choose a reference point, or as it is also called zero. To do this, determine the zero points in the corners of the base;
• in accordance with certain indicators, a cord is pulled, which will fix the height of the base pour;
• pour the solution up to the mark and level the surface.

The easiest way is to level with brickwork. Such a design, of course, will not affect the strength of the base, but it will affect the appearance in the best way. When facing with bricks, it is not at all necessary to level the sidewalls, because they will hide under the even brickwork. Bricks should be laid out according to traditional technology. The laid out material is suitable for the construction of a brick cottage.

Alignment of strip and column foundation

Both construction options must be erected especially evenly and accurately, since further construction and service of the building depend on the foundation.
The strip foundation should be leveled not only from the sides, but also horizontally. Professionals recommend not only leveling the base, but also insulating it.
The columnar foundation is used for the construction of cottages on uneven terrain. This type of foundation should also be as accurate as possible. To level the columnar foundation, you must:

• determine the value of the difference in indicators between the fixed columns;
• mount the formwork for each pile;
• determine the same pouring height on all formworks and fix it with a mark;
• install the formwork, lay the reinforcing belt and pour the prepared concrete solution;
• leave the piles to dry, remove the formwork;
• fix waterproofing material on each column.

Experts say that the foundation must be mounted in accordance with regulatory requirements, that is, correctly. Follow simple recommendations, and you will create a base for a summer house or a bathhouse with your own hands.

Construction of residential buildings from expanded clay block, gas block, foam concrete, brick, etc. mainly accompanied by the construction of a strip foundation (or strip foundation with bored piles). For the longest possible service of the house, the owners need to take the process of making the foundation as seriously as possible.

An uneven foundation can significantly reduce the technical characteristics of the future structure. In addition to the obvious problems with the subsequent erection of walls, such a foundation can create prerequisites for the rapid destruction and undesirable deformations of the supporting walls of the building.

How to level the strip foundation?

To obtain a smooth surface of the foundation strip, first of all, it is necessary to take care of high-quality formwork even before pouring concrete. Evenly exposed, the formwork can be a better guide if you provide it with marks to which the concrete mixture will be poured. For example, you can draw a line at a level corresponding to the height of the future foundation, or you can attach thin slats along this line so that the landmark is more visible. In the case when the foundation is poured without formwork (you can read more about this in the articles on the rfund.ru website), the pour is done to the level of threads stretched in advance.

But what to do if the foundation is already filled, and its surface is not even, with drops, bumps and dents? With minor defects, you can simply plaster problem areas. With more serious deformations of the foundation structure or with a strong height difference of several centimeters, leveling will be necessary.

To level the foundation for laying the first row of walls, either build up the base, or make an additional fill. In the first case, alignment occurs when laying the basement bricks, depending on the difference, two or three rows are made (more may be required), gradually reducing the difference in height due to the thickness of the mortar. This work will be required, in particular, if the walls are being built from gas blocks or foam blocks. Then the leveling base is made of bricks or expanded clay blocks.

In the second way, alignment is done using an additional surface fill. The technology used is the following.

Leveling the foundation with a layer of concrete

The surface of the tape is cleaned of dirt, stones and possibly fragile pieces of the top layer.
A new formwork is being erected, the design of which must be taken as seriously as possible. It should be as even as possible and take into account the height differences of the foundation.

On the inner side of the formwork, a mark of the level of the future foundation is drawn with a marker. Instead, this can be done as shown in the video below - formwork is made with smooth edges that are leveled. Then, right along these edges, the cement mortar will be poured and leveled.

If the elevation changes are not very strong, then liquid concrete is preferable, and with serious ones, thicker.

After concreting, the mortar must be allowed to dry, after which the formwork is removed.

How to make formwork?

You can make formwork both on your own and with the help of specialized stores. In fact, the manufacture of formwork is not a complicated process and does not have too strict manufacturing requirements, so a person can assemble it even without experience.

So, to make formwork you need:

Boards, pegs and nails, as well as props so that the formwork structure does not change shape under the mass of concrete;

With the help of boards, it is necessary to bring down the shields, one of the surfaces of which should be as even as possible;

Drive in pegs along the contour of the future foundation, which will fix the side shields from below;

Install chipped boards along the contour of the formwork. To ensure maximum evenness, it is recommended to use a level or plumb when installing;

Strengthen the structure with supports around the perimeter for reliability.

The video below shows a simple and effective technology for assembling formwork from boards, which are connected from above by transverse bars. On these bars, the formwork boards, as it were, lie on the foundation tape. But it is important that with the help of the same burusks and the screws screwed into them, it is possible to level the boards in height.

How to mix the solution?

To mix the mixture with your own hands for the foundation, you must:

Cement;
Sand;
Gravel (crushed stone), instead of which you can buy stone screenings in the store (but preferably at least 1 cm in size);
Water.

Depending on the conditions and climate where the building will be erected, you can choose:

Ordinary cement - under normal conditions;
Portland slag cement - has a similar strength with much greater resistance to moisture;
Pozzolanic Portland cement - maximum resistance to moisture, but reduced strength.

For the classic concrete mixing technology, the following proportions are used: 2 buckets of sand and 6 crushed stone are added to 1 bucket of cement. The addition of water depends on the required consistency of the solution, but the resulting solution should be moderately thick: it should not slide off the shovel too easily.

In the videos, levelers recommend 1 part cement to 3 parts sand, and often no gravel. Probably, it is worth considering what load is expected on the foundation. If we are talking about the light walls of a garage or a one-story bath, you can do without gravel. But if the alignment is done under a two-story house, it is better not to save on strength. If in doubt, consult an experienced builder.

With a layer thickness of five or more centimeters (even if this thickness is observed in some places), it is recommended to strengthen the poured foundation fittings. In simple terms, lay two reinforcement bars along the tape, tying them across with other bars cut in width (special knitting wire is sold in hardware stores). It is necessary to make sure that the concrete is poured under the long bars of the reinforcement.

Video on the topic of leveling the surface of the foundation

An interesting way to make and adjust formwork:

Foundation and laying of the first row of aerated concrete wall:

Preparation of the foundation for laying aerated concrete blocks

How to level the foundation

Our users have a question -

Is it possible to level the strip foundation with aerated concrete?

Aerated concrete does not have such strength as, say, brick. In addition, it absorbs moisture. Therefore, it is better not to level the foundation with aerated concrete. On the contrary, it is placed on an already leveled surface, and roofing material is also underlain so that moisture does not rise from the foundation.

What does it mean to "bring the foundation to zero"? This means leveling the foundation surface to a horizontal position - the upper flat part should be located in the same plane. On the one hand, the need to align horizontally arises both at the stage of pouring the mortar, and when laying the brick base, and at the stage of installing the embedded beam. At all stages, it is necessary to constantly check with the hydraulic level.

But bringing the foundation to zero is not an easy task even for some experienced builders. In private construction, the following errors usually become the causes of an uneven base:

Marking "by eye", lack of precise measuring instruments.

Inaccurate marking of the foundation or knocked down mark. In some cases, during the installation of the formwork, the cord shifts, with an orientation to which an uneven base is subsequently cast.

Heterogeneous solution. For example, a solution with an excess of water content. This happens when excessive accumulation of water occurs in one of the corners, after which a depression forms after drying.

frost heaving. It is known that it is better to build a foundation for the winter period in order to shrink it by spring. However, frost heaving provokes the rise of an unloaded belt, as a result of which, with the onset of the spring season, it becomes useless to search and set the level.

All inaccuracies and small deviations when pouring the foundation can be leveled when laying a brick base

How to avoid these mistakes? Work should be done in stages.

For example, frost heaving and shrinkage are inevitable. Therefore, work on the final alignment to zero is best done in the spring. Many inaccuracies and deviations when pouring the foundation can be leveled when laying the base.

So, spring ... And when the formwork was removed, it became clear that the foundation had a different depth ... So, first of all, it is necessary to carry out measuring work to find out the degree of curvature. The method of correcting it depends on the differences in the height of the foundation.

Common disadvantages of the foundation in private construction:

the foundation is poured crookedly;

corners are not observed;

dimensions are not met;

diagonals broken;

not enough width around the perimeter;

uneven base height.

There are several common fixes. So, shortcomings in the differences in the thickness of the monolith can be corrected by pouring a monolithic belt - this is one of the most effective ways. The second effective way is the construction of a brick belt.

Leveling the horizontal surface of the foundation is called differently:

• bringing the base to zero;
• horizontal comparison;
• leveling, etc.

But the goal in any case remains the same and is to maximize the alignment of the upper surface of the foundation. Most often, it is proposed to re-erect the formwork and again set the horizon level using a level. The bottom line is to determine the highest and lowest point of the concrete tape. By the way, this method can also be used if instead of a monolith there are prefabricated blocks.

It is recommended to take the highest point as the initial mark. This greatly simplifies the work, since it is not required to knock down an artificial stone. In addition, as a result of chips, reinforcing bars may be exposed, which is highly undesirable.

The zero level is planned in the same way as during the initial pouring of concrete into the formwork. The only difference is the corrected base height. Experienced craftsmen recommend marking "zero" in the corners, making cuts in the formwork at the right level. A strong cord is driven into the prepared slots, after which it is pulled tightly between the control points. This will become a kind of lengthy beacon and will allow you to abandon other marks. The disadvantage of this method is a certain mobility of the cord relative to the horizon. Beacons made of timber do not have such a minus.

In places where the foundation is skewed in height by more than 50 mm, it is recommended to lay a reinforcing mesh

After the preparatory work, the top of the main foundation is poured with cement mortar. It should have a more liquid consistency compared to the concrete mixture that was used previously. After the initial setting of the cement, the surface is smoothed.

Fixing a foundation or building a new one?

The curvature of the lines of the base of the house can have various types. Some of them can be fixed, others are more difficult. There are also those that cannot be corrected. For example, if the foundation is not only curved, but has sufficient strength. Low strength is the largest foundation defect. Usually such a foundation should be viewed as a bad experience.

If, after removing the formwork, large cavities are found, if, when tapped with a sledgehammer, it crumbles, bursts, pieces of concrete fall off from it, no house, even a light one, can be built on such a foundation. It will crumble in the near future. Such a foundation is usually demolished. In such cases, experienced craftsmen are consulted or skilled workers are hired and a new foundation is laid for the future structure.

If the foundation is strong, it is quite possible to save it.

An example of a curved foundation. Curvature inside, it is not critical. Cracks, swelling are not visible. You don't need to dismantle anything. A possible fix is ​​to put 3-4 rows of red brick on top of the concrete base. If the house is brick, laying should not be done along the perimeter of the basement, but along diagonals that are equal to each other. From one corner, a brick will overhang 3.5-5 cm. On the other hand, the brick will be displaced into the well by 3.5-5 cm, which is not critical. From a flat rectangular masonry, you can safely build.

Correcting the curvature of the side walls and surfaces, carry out the following actions:

carefully check all dimensions;

designate corners and borders;

formwork is installed;

holes are drilled in the foundation, where reinforcement of the required length is inserted;

carefully prepare a solution with gravel of a fraction of 2-3 cm, and make a corrective fill;

compact the poured concrete with a vibrator;

use a water level to level the top layer.

When drilling holes, take a drill two units lower than the reinforcement used. For example, drill No. 12, reinforcement thickness No. 14. They are drilled into the foundation 15 cm deep, but not more than 1/2 of the thickness of the base.

Discussion on the construction forums

With even concrete pouring of the basement, a brick is sometimes not needed. But we are considering a fairly common option - when the foundation tape does not withstand the horizontal.

The question arises: is it necessary to bring the foundation to zero with a brick or other material, or can the upper part of the foundation be filled in level. This question is often discussed on construction forums.

On FORUMHOUSE and other construction forums, they ask for advice on how to easily bring the foundation to zero if the foundation is uneven.

If there is a height difference of a maximum of 12 centimeters, options are considered: 1. formwork and fill it with concrete according to the level, 2. the previous option, with butting with bricks (in places where the difference is large), 3. do not bring the foundation to zero, achieve the horizontality of the piping beam by laying boards and a beam of the required thickness in the right places directly when installing the lower piping beam.

Some believe that between the already poured foundation and the future building, it is imperative to perform waterproofing and lay a belt with red brick, the least susceptible to moisture (i.e., it is considered as a waterproofing). They even say categorically: "They don't build houses without red bricks." That is, in their opinion, one cannot do without the work of a bricklayer.

Others believe that pouring under “zero” or reporting with a brick depends on specific goals. For example, a 30 * 40 cm foundation tape under a large bath, which needs to be placed high from possible flooding - another +40 cm. “So don’t pour another 40 cm, I’ll lay it out with bricks ...”

But there are opinions that it will be possible to fill in according to the established level if the solution is liquid. Brick can be used for large volumes of work, and in small buildings it is suggested to do this with additional formwork and “bring it to zero” with a liquid mortar. Already on top they offer roofing material in 2-3 layers, this is a reliable, time-tested material.

If the curvature of the foundation is insignificant ...

The curvature of the top layer is considered insignificant if it does not exceed 5 cm. Such a disadvantage is leveled to the level with cement mortar M 200 using a plaster mesh. It is fixed with dowels hammered at a distance of no more than 25 cm from each other.

If the curvature passes from the side of the front side, this is a cosmetic defect. It does not affect the strength of the house being built. Nothing needs to be done until the end of the construction work. After the construction is completed, this drawback can be easily eliminated if you start lining the basement with tiles, tiles or natural stone using a plaster mesh, etc.

Watch the video. Leveling a crooked foundation

Filling a monolithic belt

If the height of the drops is more than 5 cm, the foundation should be increased by making a monolithic belt. This is a reinforced concrete belt, which is created by pouring concrete onto a reinforced surface or plane. Monolithic belts are an integral part of construction. They serve to level the surface under the floor slab. At the same time, it provides a flat surface and contributes to a uniform distribution of the load around the entire perimeter.

The technology boils down to the fact that formwork is mounted around the perimeter of the foundation. The material for the formwork is a board, plywood, OSB-plates. The upper part of the formwork is installed in a horizontal plane and is specified using a level or plumb line. Reinforcement is placed in the formwork. A metal frame is created from reinforcement of 4-6 rods of a periodic profile with a diameter of 12 mm and tying with a wire with a diameter of 4 mm. All are poured with concrete grade M 200 on fine aggregate. The thickness of the monolithic belt should be 15 cm or more.

It is very important to clearly set the upper level of the formwork, and then fill the box "to the eyeballs". In this case, they talk about the initial removal of the base to zero. The method gives good results, but its implementation requires certain skills and ideal formwork geometry in height.

A monolithic belt is a reinforced concrete structure that does not have heat-insulating properties. Therefore, sections of the monolithic belt should be insulated.

Leveling with masonry

Small differences can be leveled with brickwork. It is advisable to use a solid ceramic brick of plastic pressing M 125. It has significant heat-insulating properties. With the help of a more viscous mortar and brick M 125, it is possible to even out the unevenness of the foundation by overlaying it or building up the upper part.

lesovoz_69 Own house country house, watch video, construction, foundationHow to fix a crooked foundation and bring it to zero What does it mean to "bring the foundation to zero"? This means leveling the foundation surface to a horizontal position - the upper flat part should be located in the same plane. On the one hand, the need to equalize horizontally arises both at the stage of pouring the mortar, and when laying a brick base, and at ...lesovoz_69 lesovoz_69 lesovoz_69 website [email protected] Author In the middle of Russia

The foundation is the main part of any building. It is important that it is even horizontally and vertically. This largely depends on the base of the foundation and the evenness of the formwork. In this article we will tell you how to align the formwork for the foundation along the horizon and the vertical edges of the base.

Subtleties affecting the quality of the design

To maintain the evenness of the base, extreme points are determined. With the help of them, the boundaries of the building are determined. Before you begin to install the reinforcing cage and pour the foundation, a gravel base is laid. Although no one will pay attention to it after the construction of the building, this layer affects the strength of the higher structures.

It is customary to make a pillow about 0.2 meters thick. Which layer is required in a particular project depends on the type of soil and the mass of the building.

In addition to the base of the foundation, attention should be paid to the evenness of the sides. To do this, use the formwork, set horizontally. If you get uneven sides, then you can correct the situation without destroying the structure.

In those parts where the insulation will be laid, it is necessary to observe the maximum evenness of the surface. If you allow pits or convex places, then you will not be able to lay the wall material evenly. Moisture can get into the cavities that appear, destroying the wall from the inside. To level the horizontal plane of the foundation, you will need the following tools and materials:

• Trowel, shovel, hammer, etc.;
• Reinforcing mesh for leveling differences more than 5 cm;
• Wooden boards for formwork;
• Material for concrete (cement, sand, crushed stone, water);
• Control measuring instruments for leveling the foundation formwork (level, hydraulic level).

Leveling the plane of the strip foundation

Even if all the recommendations are followed, an uneven horizontal base may result. You can correct the situation by leveling the formwork for the foundation. Formwork rises along the side walls of the strip foundation. If the height of the leveled surface is more than five centimeters, a reinforcing mesh will be required.

There are several ways to determine the exact height along the entire perimeter of the formwork:

• Draw marks on the inner surface, then fill to their level;
• When installing the formwork, initially set the upper part of the boards to the level. In this case, it will be necessary to pour concrete to the border;
• Sew on the slats at the required height. Such a label will not be erased and will be clearly visible.

How to use the laser level

Aligning the vertical strip foundation

The strength of the building does not depend on the verticality of the foundation walls. This indicator only affects the appearance of the house. Simple plastering will help to solve the problem of uneven walls. In those places where the depth of the depressions is more than five centimeters, a reinforcing mesh is mounted. To ensure the verticality of the finished plaster, you can use a rule, slats or building level. If you plan to finish or decorate the outer part of the foundation, then it is not necessary to separately plaster the surface. The plane is leveled with finishing materials.

Another case is a serious deviation from the vertical, skew. If such a problem occurs, the formwork is re-erected along the finished foundation. If the distance between them is more than 0.5 meters, then a reinforcing frame is required. This will help create a solid foundation for the house under construction.

Leveling the column foundation

Usually this type of foundation is used for light structures - baths, gazebos, terraces. The material of the pillars is very diverse - brick, concrete or pipes can be used.

Alignment of the horizontal surface of all concrete pillars occurs like a strip foundation. Formwork is used for building, the upper part of which is installed in a single plane with all the pillars. If the difference is more than five centimeters, a reinforcing mesh is laid.

The columnar foundation of metal pipes is leveled at the minimum height. The excess is cut off by a grinder or gas welding equipment.

Thanks for the advice!
I tried my idea anyway. I'll post a pic later when I take the formwork off. I give a small comment on this technology, maybe it will be useful to someone.

In general, the method turned out to be quite technologically advanced. Most of the time is spent preparing fasteners for the formwork. The installation itself, alignment, laying the screed are done quickly enough, without any problems.
In the course of work, I found vertical curvature in some places (bulging). This is not a problem, iron profiles are quite bent. In some limits, even without pruning. I thought there would be problems that the profile does not fit snugly - also not a problem. Of course, it is impossible to fill it with a liquid floor, but it is quite liquid even with a solution.

I will summarize the main points:
Fasteners:
- In addition to the elements drawn in the picture, I also had to make pegs against which the retaining boards rest
- for a vertical, and especially for a retaining board, something flexible, such as lining, is best suited
- the retaining board must rest below the pressing bar
- the longer the retaining board, the more convenient
- I put fasteners in 3 pieces per 3 meters of the profile, and I put the extreme supports at the junction of the profiles
- the bars fit tightly into the profile, so that the walls of the profile were bursting, they had to be trimmed so that they freely entered

Profile:
- the profile took 27 by 60 thin (it is cheaper and bends better)
- within reasonable limits bends
- if the irregularities are too large, then at the place of the bend, the side walls of the profile will bend up or down, which will worsen the picture, then you just need to cut it with a grinder at the place of the bend
- No overlaps at the joints
- in the inner corners on one of the profiles, I cut off the sides with a grinder, and left the vertical side

Installation:
- I drive a vertical board a little
- I put a bar, put a retaining board below the bar and mark the peg. scoring
- It is better to put the extreme supports first, because in the middle of the profile you may need to put them not in the middle, but where it fits worse if the foundation is curved
- when all the supports are installed, we put the profile
- we lay the bars, remove the retaining sticks, take away the vertical ones and put the profile there.
- then we put support sticks, we look where to put the middle supports or whether they need to be moved.
- when all the profiles are set, we begin to align
- first ran the level, found the maximum point. We start with her.
- we set the height of the screed to the maximum point (it is clear that it is better to make it minimum.
- and then just adjust the level of all profiles
- even just a leaning support stick holds the profile well and allows it to be exposed. You can even press a little, and correct the profile with a hammer.
- I leveled with a simple level - one short, one long
- after leveling, press with a support stick. Holds, did not even have to screw in the screws from slipping.
- in general, it is quite convenient, you can do everything alone. 10 meters I cut a profile and put it somewhere in an hour
- the maximum height of the screed came out under 2 cm

Solution:
- I made sand concrete M300.
- there are small pebbles in it, but in general they do not interfere
- at first I kneaded it thicker, I thought it would flow out into the cracks, but one batch turned out to be watery and nothing, it’s even more convenient to level

Alignment:
- A piece of profile is ideal for alignment. Bend its sides with a hammer, but just do not knock on the fold line.
- stock up on two rules - one is slightly longer than the width of the foundation, so that it only rests on the edges of the formwork, the second is longer so that you can align the corners of the tape