Do-it-yourself screed from cracks at home. How to properly pull off the walls of a brick house Screed a house with an internal corner reinforcement

One of the most popular materials for construction various objects is a brick. However, this material is not ideal, and flaws and damage can occur in buildings made of it during their operation.

The most common flaw is wall cracks. Correcting such a defect will not be difficult. To do this, you need to find out the cause of the crack and select the necessary technological method to eliminate it.

Peculiarities

Cracking on brick wall surfaces is a bad sign. However, with a properly laid foundation and correct execution masonry cracks should not occur.

Any visible flaw signals non-compliance with the norms of construction or use and needs to be immediately corrected for the cause of its appearance. The level of difficulty in sealing cracks in wall surfaces depends on their thickness and depth (sometimes you have to disassemble the required area of the brickwork).

You can fill the crack with your own hands if you follow our recommendations. We will help you fix any imperfections (eg cracked surface of a load-bearing wall).

Causes of cracks

There are several reasons for this frustrating problem.

The absence or inadequacy of the link between the blocks. It manifests itself in the form of a vertical crack along the entire height of the wall (occurs when constructing an extension to an existing building or when the correctness of the work is not observed). You can get rid of the gap only if a preliminary screed is made with a reinforced belt.
Disadvantages when laying the foundation of the building: pouring the foundation to a shallow depth (less than the level of soil freezing), the use of granular or mineral blocks, the use of concrete with poor strength and resistance to frost. External manifestations: crevices in corners or rapidly growing cracks in the tops of brick wall surfaces.

This can be avoided by strengthening the perimeter of the foundation by creating a belt of concrete.

Erroneous determination of soil quality, due to which errors occur when taking into account the load. This also includes soil deformation due to vibrations, natural phenomena(e.g. active groundwater), as well as work performed in the vicinity of the object. All this leads to the appearance of large cracks along the entire surface of the walls.
Settlement of the structure during the first year of operation. This manifests itself in the form of small and shallow gaps, which do not further increase in size. To eliminate them, only minor repairs need to be made.

To repair a crack in the wall brick house, you should follow a simple instruction:

carefully inspect the entire building, recognize and eliminate cracks;
periodically check the condition of wall surfaces;
if the slightest cracks are detected, everything possible should be done immediately to prevent the spread of defects;
when cracks form, it is necessary to clear the necessary inner area of the cracks, as well as to maximize the interaction with finishing agents;
after checking the walls and processing the cracks, the detected cavities should be covered and the outer insulation (or decoration) should be made.

Before determining the cause of the flaw, it is pointless to do anything to fix it.

In addition, it is necessary to continuously check the rate of crack growth. To do this, the gap must be marked with markings from the putty composition or concrete mortar... Desirable strip sizes are 100x40mm with a layer thickness of less than ten millimeters. There is also an easier method using paper. Check for breaks every day for five weeks. If problems arise, a major overhaul of the base of the structure and the help of a professional are required.

It is worth remembering that a crack width of more than twenty millimeters is critical. In such a situation, an auxiliary reinforcement of the edges of the cracks and the strengthening of brick structures are necessary. Destructive areas need to be dismantled.

If after checking you noted that the crack has not increased, then you can use simple method sealing a gap in a brick wall.

Crack fixation methods

It is worth remembering that the occurrence of vertical crevices with a width of ten millimeters or more is a harbinger of the destruction of the walls of the structure. Therefore, it will not be possible to repair this crack with cement mortar without a strong metal screed. In this regard, there are several repair options.

Driving in special anchors made of metal into dowels mounted on the edges of the crack.
Installation of longitudinal metal brackets with bends at the edges into pre-made holes in wall surfaces (later they should be covered with cement mortar). This method is the easiest and most reliable when correcting through cracks with outside.

Reinforcement of brickwork with inside special bonding joints. When mounting fasteners into the wall surface, they must be recessed to a great depth (more than half of the entire wall thickness). It is quite possible to alternate fasteners. In practice, the filling of gaps in brick wall surfaces is carried out after the installation of the fixing structures.
Using reinforcement mesh it is rational, if desired, to strengthen the entire area of the structure, because even a careful calculation of the foundation does not guarantee the absence of the risk of shrinkage. When choosing a method and material for eliminating cracks, it is necessary to take into account the forthcoming exterior decoration... All items from metal material are treated with anti-corrosion compounds and masked by painting or plastered over with plaster.

How to repair cracks

Compositions for sealing gaps depend on the location of the flaws (from the inside, outside the house, or even under the window). Inside the room, it is possible to tighten the crack with a gypsum-based composition or a mixture of lime and cement. For outdoor installation, it is better to choose the materials that are most resistant to moisture (otherwise, the finish will not last long).

For minor cracks(less than five millimeters wide) repair with cement mortar is suitable. In situations where shrinkage microscopic cracking does not exceed one millimeter, it is better to cover them with epoxy resin.
For defects with a length of five to ten millimeters the embedding can be done with a mixture of cement and sand in a ratio of 1: 2 or 1: 3. To achieve a plastic consistency, add water.
For more problematic cracks in wall structures made of bricks (as well as in structures with an air layer) a great solution will become foam for installation. Such material requires mandatory protection from sunlight, therefore, after hardening, the foaming surpluses are removed.

For defects of various types fit cement composition with the addition of polymers from the category of M400 grades. The compositions are passed through a fine grate with medium-sized grains of sand or wood glue based on polyvinyl acetate and water. PVA in such cases is added in excess (from one liter per bucket) and added to the composition last.
For problem areas walls(inside or outside), you can use a silicone based sealant. The advantages of such a tool include plasticity and a long service life of the material, tolerance to changes in temperature and humidity, the convenience of sealing cracks using assembly gun... Disadvantage this method are large financial costs, so for large areas and volumes it does not fit.
If it is necessary to eliminate defects from the outside and in the presence of an outdated solution, mixtures with the addition of brick crumbs are used.

At the end of the repair, the condition of the brick surfaces must be carefully inspected within two months.

A crack on a building is not only unaesthetic, but also dangerous. After all, a crack outside is only a consequence, and the reason is deeper - these are cracks in the foundation itself, and this is a direct path to the accident rate of the house and its further destruction. Often there is neither the desire nor the opportunity to build a new building, so a way was invented to preserve the existing structure - screed the house with reinforcement. But before proceeding with the repair, you need to understand all the nuances. Screed at home, the price of work depends on their complexity and, of course, the cost of expensive materials. All this will help you to calculate the builder who this work will perform. The screed of a private house with corners can be done independently, which will lead to significant savings. Buy in advance all the materials required, but also keep in mind that certain skills are needed for the foundation that requires strengthening.

Screed houses with reinforcement need to be done with a fairly serious knowledge of welding and calculation of the required diameter of the reinforcement. Its size is chosen depending on the degree of destruction, the number of storeys of the house and its size. But experts also take into account the roof, its shape and coating, the type of foundation, soil and even the region of residence. The layman may not take into account all these nuances, and the price of a house screed with fittings, which is not so high, is a serious matter and let professionals do it.

If the crack has gone on some small areas of the house, then it is advisable, before the screed of the walls of the house with reinforcement is performed, to lay them out again. Particularly stressed areas can be tightened with thicker, reinforced reinforcement. To implement a screed at home with reinforcement, not so much is needed building materials: the reinforcement itself of the required diameter, studs corresponding to the size and section of the reinforcement, washers and nuts.

The technology for installing the reinforcement is quite simple - stops for the bar are welded on the corners, the level must be different for each wall, this is done in order to avoid abutting the studs and nuts. The resulting corners are attached to the corners of the house, then studs are threaded into the stops, onto which washers are put on and nuts are screwed on. With the help of nuts, the screed of the house is carried out.

When screeding a house with fittings, do not immediately tighten the nuts too much, do it gradually, especially since periodically, about once every six months, the nuts must be re-tightened. The cost of a screed corner at home can be found on the Internet in order to navigate its ranges.

After the work carried out, the final stage remained - priming and painting. House screed whose prices differ depending on the selected fittings, will in any case be an economical option for you. After all, cracked walls are much easier to repair than to bring anew. The cost of pulling together a cracked house will help determine the master who will work on its repair.

If the cracks are very large and deformation occurs in different directions, then the screed of the house with reinforcement will not be able to completely eliminate the defects, it is designed to reduce lateral forces, for the complete fixation of the house, it is necessary to strengthen and strengthen the foundation.

How much does a screed cost?

Screed houses with fittings, the price of which depends on the professionalism and quality of the work of the performers. These renovation work are a good and reliable solution to eliminate small cracks and they are widely used in practice.
But do not forget that self-pulling at home requires serious knowledge of welding on this, if this knowledge is not available, then it is better to trust a specialist to carry out all the planned repairs.

Armature

Reinforcement is a collection of interconnected particles and elements, which, together with a material such as concrete, in reinforced concrete structures are perceived as beams that stretch stress. Reinforcement bars are also used to reinforce concrete in columns.

Reinforcement elements are divided into rigid (angles, channels, rolled I-beams) and flexible (rods of periodic and smooth profiles, as well as knitted or welded frames and meshes).

Consider the classification of types of reinforcement.

Depending on the purpose, fittings are:
- working (the section is assigned by calculation, the forces in the particles of the main load are perceived);
- structural (distribution fittings, perceiving shrinkage / expansion, exposure temperature);
- assembly (installed to combine the structural and working parts); - anchor (embedded parts).

Depending on the orientation in the structure:
- transverse reinforcement, which actively prevents the formation of cracks from the arising stresses near the supports and connects concrete to the reinforcement from the compressed zone in the tensioned zone;
- longitudinal reinforcement, fully and completely absorbing tensile stresses, preventing the formation of cracks in the tensioned zones of the structure.

Depending on the conditions of use, the fittings are:
- unstrained;
- strained.

In pre-stressed reinforced concrete structures, the prestressed reinforcement is exclusively working.

There are five options for reinforcement and concrete contacts:
- contact with concrete structures by friction;
- connection on shear bonds;
- adhesion (the process of joining when concreting a steel reinforcing element);
- interaction cement mortar and steel fittings at the electrochemical level;
- compression of reinforcement with concrete after shrinkage.

If it so happens that a crack has gone along the load-bearing wall or foundation, this is not yet a sentence, it’s just time to take radical measures to strengthen the entire structure. We will talk about the most simple and popular methods of preserving the integrity of a building in this article.

Note. The article uses conditional terminology.

When purchasing a ready-made house, the new owner in all cases deals with a pig in a poke. And it doesn't matter if it is a new building or a renovated old one. Builders build and repair cottages and private houses in a fantastically short time, which always affects their stability and durability. Regardless of the reasons for its appearance, a crack is a frequent and faithful companion of stone buildings and structures. We will talk about the most difficult cases of these unpleasant and dangerous defects - structural cracks, which serve as signals of the appearance of the mobility of the bearing elements. To stop the crack propagation, the movement should be stopped and the elements fixed, and then repaired and "masked".

Note. A crack in the finish does not always mean the presence of defects in the wall material. Make sure that the damage is exactly carrier material removing some of the trim and exposing the defective area for observation.

Let's leave the theory and consider the three most common cases of the appearance of element mobility: collapse, blockage and separation of the extension.

Collapse

In the event of a collapse, the walls and corners have a visual outward deviation from the vertical, sometimes wavy. Walls can also be deformed in waves or deflected by the entire plane. In most cases, this is accompanied by the appearance of cracks in the upper corners of the door and window openings.

By the degree of coverage, the collapse can be:

Complete. All load-bearing external walls are deformed to varying degrees.
Incomplete (partial). Some walls are deformed.

In both cases, even if only one wall is collapsing, we recommend applying a preventive screed on all sides to prevent the development of movement on other walls.

Depending on the degree of collapse of the walls, measures of different depth of influence are used. We will conditionally divide the degree of collapse into three categories - light, medium and strong, and tell you what to apply in each case.

Light camber

Signs

The tops of the walls are noticeably deformed in the area up to 1/3 of the height of the wall (without the height of the foundation). Cracks in the corners of the openings in 50% of cases. The rest of the walls and foundations are normal (no cracks, deformations).

Cause

Occurs due to the unreliability or lack of an armored belt, roof overload, during construction attic floor on the old walls.

Note. The most common mistake leading to roof overload is unaccounted snow load.

Elimination method

In this case, it is reasonable to use a steel mono-yoke (hereinafter referred to as the cage) on the corner stops for screed walls. At the same time, as in all cases of using various clips, the rods will pass from the outside along the facade load-bearing walls standing in the shape of a rectangle. Sometimes it is necessary to make technological openings for rods in the walls of the outbuildings.

What you need:

Steel corner 100x100 mm (minimum 75x75) - 4 m.
Pipe 1 inch - 1 m.
Stud with thread 20 mm - 4 m.
Stud nuts and washers.
A circle (steel bar) with a diameter of 20 mm or a strip of 40x4 mm - as long as the perimeter of the house.
Welding, painting.

Note. It is undesirable to use fittings for rods, since they are not designed for outdoor work and are subject to corrosion.

How to make an angular stop: on a steel corner 100x100 mm long, equal to the distance from the top of the wall to the top of the window openings plus 20%, pipe sections 150 mm long are welded on.

The number of stops is equal to the number of corners (4).

Work order:

The rods (strips) are welded into two continuous lashes with a length along the walls of the house minus 200 mm (per tightening stroke).
Then hairpins with a free end of 200 mm are welded at the ends of the lashes.
The pins are threaded into the tubes and the lashes are welded together in the middle.
The entire structure is assembled on the ground and fixed at the required height.
The nuts are tightened to a state of tension.

Attention! When using steel clips and ties, remember that they are for anchoring walls. An attempt to return the walls to their original state can result in breaks and sagging areas.

The design of the steel race may vary. For example, in the case of undulating deformations, a channel can be used as one, several or all four rods. Installation will be more difficult, but the entire load from the wall will be evenly distributed over the rigid channel.

Average camber

Signs

All signs of slight collapse extend up to 50% of the wall height (excluding the foundation). The probability of cracks in the corners and boundaries of openings is 80%.

Cause

Weak armopoyas. Lack of a bunch of corners and masonry in the wall material, high material wear, overload.

Elimination method

In these cases, a solid corner cage is used. It is arranged similarly to a mono-holder, but along the entire height of the wall and has more tie belts. With an average camber, it is recommended to arrange three belts.

In all cases, the circle can be replaced with a 10x40 mm steel strip.

Attention! The welds must be good quality(they hold the load). Overlap - 250 mm.

Strong camber

Signs

All signs of medium and light, but at a level of more than 50%. In the overwhelming majority of cases, it is accompanied by the appearance of deep, sometimes open, cracks along the walls and foundation.

Cause

Most often, deformations of the base or foundation are combined with the causes of slight to medium collapse. May be accompanied by partial destruction of the foundation.

Elimination method

For repairs, a solid corner cage and a retaining wall (support) or a retaining belt of the foundation are used.

The retaining wall or support is part of the reinforcement belt applied in the deformed area.

Support belt - repair structural element designed to strengthen existing foundation walls along their entire length. It is used when it is necessary to strengthen the foundation. Material - reinforced concrete.

Back-up device. Let's consider an example of a corner section. A solid belt is arranged in a similar way.

First you need to determine the size of the backwater. If we had to resort to such radical measures, it means that it is too late to calculate the load, especially since existing foundation stays in place. Therefore, we simplify the calculations in the direction of increasing the safety factor. The backing thickness should be 50% of the foundation wall thickness, but not less than 400 mm. If possible, the bottom of the backwater and the foundation should be at the same level. The optimal ratio of the aboveground to the underground is 1 third above the ground, 2 thirds below the ground.

Attention! Reinforcement rods at the corners must be solid (bent at 90 °). The minimum side of the corner support is equal to three support thicknesses.

Work order:

We excavate the damaged area and clean the trench. We clean the wall of the foundation from oils and organics, residues of waterproofing.
We drill holes with a diameter of 18 mm into the wall of the foundation to a depth of 200 mm in a checkerboard pattern with a step of 200 mm.
We drive in reinforcing pins with a diameter of 16 mm and a length equal to the thickness of the support plus 200 mm (hammered into the wall) minus 40 mm (protective layer).
We tie a working reinforcement with a diameter of 16 mm with a pitch of 200 mm to the pins with a knitting wire.
We make U-shaped clamps from 10 mm reinforcement according to the dimensions of the frame of the beam (support) 600x360x600 mm (workpiece length 1600 mm) and install them with a step of 200 mm.
We install the formwork by size.
We lay concrete (factory or prepared on site) with vibration.
After the concrete has set (3 days), we remove the formwork and apply waterproofing.
We produce backfill soil with ramming and pouring.

Backwater reinforcement: 1 - foundation; 2 - working L-shaped rods Ø 16 mm; 3 - formwork; 4 - U-shaped clamps Ø 10 mm; 5 - rods driven into the foundation, Ø 16 mm

Costs for the device 1 lin. m backing with a thickness of 400 mm, a height of 600 mm in the manufacture of concrete on site:

Name	Unit rev.	Qty.	Unit price, rub.	Total cost, rub.	Note
Rebar 16	running. m	20	30	600	Wall pins and work rods
Rebar 10	running. m	10	20	200	U-shaped clamps
Knitting wire	Kg	0,5	200	100	Snapping all elements of the wireframe
Concrete	cub. m	0,25	1000	250
Waterproofing	sq. m	1	20	20
Formwork costs	sq. m	1	100	100	Self-tapping screws, nails, boards
Additional expenses	-	-	300	300	Disks, drill, etc.
Total material				1570	Depends on local conditions and contract
Work				1000
Total material and work				2570

Blockage

The walls are piled up inside the building. Can be complete or partial (incomplete). In different degrees of deformation (light, medium, strong) one stop method is used.

Note. To repair the blockage, you will need to carry out welding works indoors, which is most often associated with conducting overhaul the whole building. Take care of fire safety.

Full blockage

Sign

Three or more walls are piled up inside the building (to varying degrees).

Cause

Weak armored belt, material wear, violation of technology during construction (weak solution, lack of corner reinforcement, etc.).

Elimination method

Rigid spacer self-supporting steel cage (frame) on through fastening.

What you need:

Rotary hammer with a drill 18-20 mm.
Channel 50x100-150 - length equal to the perimeter of the walls that need to be reinforced.
Steel plate 200x200x3-4 mm (up to 300x300).
Reinforcement 16 - 3 wall thicknesses for each running meter of the frame.
Good welding (tension), painting.

Operating procedure:

Determine the perimeter of the walls to be reinforced. If necessary, we punch technological holes (for the channel) in the partitions.
We divide each wall into steps close to 600-700 mm (but no more). We retreat ½ step from each corner.
Burim through holes 18-20 mm.
On steel plates, perpendicularly weld reinforcement pins with a length equal to the wall thickness plus 100 mm.
We install the resulting anchors into the holes with the plate outward.
Trying on each channel from the inside, mark it under the holes.
We burn the holes in the channel for the reinforcement by welding.
We paint the outer shelf of the channel with a primer (it will adhere to the wall).
We install the channel on the pins in the holes.
We weld the pins in the holes.
In the same way, we install the continuation of the channel.
When the entire perimeter is installed, we weld the channel to each other along the joint and make welded linings from reinforcement 16 - 2 per joint with an overlap of 300 mm.
We reinforce the corners in any way possible (for welding).

Ideal for such a clip - if it will then be covered with a suspended ceiling. Then you can arrange diagonal rods. If false ceiling not expected, we close the tire with a box.

Attention! The plates on the outside and the reinforcement welded to them passing through the inside of the wall are a strong cold bridge and it will destroy the wall with condensation. Be sure to insulate the plates, and preferably the entire wall.

Partial blockage

Sign

One or two walls are overwhelmed.

Cause

The walls are located close to a busy roadway (with tram). Washing with atmospheric waters.

Elimination method

Partial cage arrangement according to the solid principle. The side of the interrupted corner is equal to one third of the length of the heaped wall, but not less than 1.5 meters.

Arrangement of a partial inner cage: 1 - wall with a blockage; 2 - reinforcement with a plate; 3 - channel 100x50x4 mm

With combined collapses / rubble (when the walls diverge into different sides), use the inner frame (first of all) and the outer screed (secondly) together. IN severe cases use all amplification options at once or their combination.

Cost calculation 1 running meter inner cage:

Outbuilding department

Let's consider the most difficult and at the same time popular case - the combined one.

Sign

A through crack along the inner corner or at the junction of the extension with the main building with a medium to strong collapse of the outer wall.

Cause

Lack of attachment to the wall of the main building during the construction of the extension (in 90% of cases). Weak foundation under the walls of the extension. Overloading of the extension (superstructure, balcony).

Elimination method

Combination of through, semi-through or anchor cage and back-up:

Through cage - the rods pass through the load-bearing wall and are fixed (nuts, welding) on a thrust bar or plate located on the inner side of the wall.
Semi-through cage - one side is of the through type, the other is fixed from the outside to the embedded part.
Anchor clip - rods are attached to embedded parts, arranged on anchors in the walls of the building.

Extension screed options: 1 - semi-through; 2 - through; 3 - anchor; 4 - corners 100x100 mm; 5 - rods (rod, plate); 6 - capital walls; 7 - plate with anchor; 8 - plate 4 mm

You can arrange any of these types of clips using the instructions above.

Rules for the construction of anchor rods:

A thrust bar or plate located inside the building must not hit the top of the doorway.
Arrange embeddable parts in the walls at a distance of 1/3 of the extension wall length, set aside from the junction of the walls, but not less than 1.5 meters. Drill 3 points with a diameter from 12 mm, depth 2/3 of the wall thickness.
If the number of anchor rods is more than 2, place them with a break along the length of 1 meter.
The walls of the main building should be free from deformations and cracks.

The support can be as separate (under outside wall), and along the entire length of the foundation of the extension. In this case, the reinforcement is driven into the foundation of the main building at an angle.

Most often, the types of deformations described above occur in houses made of marl or bricks laid on clay. Even in the case of the initial stage of deformations (the appearance of small cracks), we recommend using a preventive screed at home on corner frames. Remember that any metal passing through the wall into the room is a cold bridge and will negatively affect the condition of the wall if it is not insulated.

Vitaly Dolbinov, rmnt.ru

Note. The article uses conditional terminology.

Note. A crack in the finish does not always mean the presence of defects in the wall material. Make sure that it is the carrier material that is damaged by removing some of the trim and exposing the defective area for observation.

Let's leave the theory and consider the three most common cases of the appearance of element mobility: collapse, blockage and separation of the extension.

Collapse

By the degree of coverage, the collapse can be:

Complete. All load-bearing external walls are deformed to varying degrees.
Incomplete (partial). Some walls are deformed.

In both cases, even if only one wall is collapsing, we recommend applying a preventive screed on all sides to prevent the development of movement on other walls.