Do-it-yourself wall repair—sealing cracks and eliminating other defects. We tell you in detail how to repair a crack in a wall with your own hands securely and permanently. How to hide cracks.

Concrete coverings are used in a variety of areas: when installing floors, concreting surfaces in both industrial and residential buildings, highway construction and much more. However, concrete has a low tensile strength, so during the hardening process the mixture contracts slightly and shrinkage of the structures occurs. Because of this, minor and more serious defects appear on the surface. In this case, sealing of cracks in concrete is required, which is carried out according to different technologies depending on the type of damage and the cause of its occurrence.

Types of cracks in concrete

Some novice or unscrupulous builders prefer to simply cover up a hole or any other defect with putty or mortar. However, before you repair a hole or crack in a concrete wall or other foundations, it is worth understanding what exactly caused such troubles to occur.

There are several types of defects:

Superficial. Such cracks often appear after pouring the foundation during the drying of the sand-cement mortar, if the mixture was prepared without observing the required proportions of the components, low-quality components were used, or there was not enough water in the mixture.
Shrinkage cracks (also called hairline cracks). Defects of this type are considered the most dangerous, since they cause not only deformation of the fundamental foundation, but also the entire building as a whole. This leads to a decrease in strength. Defects of this type appear when there is an uneven load on the foundation and when the cement composition is incorrectly selected.

Temperature-shrinkable. Cracks of this type appear during the hardening process of the concrete base due to the exothermic reaction occurring between cement and water. Very often, when constructing walls and ceilings, novice builders do not take into account the freedom of deformation, as a result of which temperature stress occurs in the concrete mass and defects appear on the surface.
Cracks and holes appearing due to poor quality reinforcement. If the frame for strengthening the structure is too weak, it will bend under loads, which will also lead to the formation of defects. In addition, the reinforcing rods may begin to oxidize. Due to corrosion, the material increases in size, tearing the concrete mass from the inside.

Concrete surfaces located outdoors are also susceptible to cracking. The external environment contains chemically active substances that create favorable conditions for the appearance of defects.

In addition, sharp temperature changes, which can occur both on the surface and in the thickness of the concrete, have a destructive effect. At the same time, it has a detrimental effect not only cold air, but also ultraviolet.

It is also worth paying attention to the width of the cracks, since in some cases such defects are not critical.

Acceptable crack sizes

In the construction industry there is such a definition as the permissible crack opening width, which is determined according to DBN V.2.6-98:2009 based on operating conditions:

The crack size should not exceed 0.5 mm if the concrete surface is not exposed to weather conditions. That is, it is not affected by moisture, low temperatures and ultraviolet radiation.
The permissible crack opening width cannot be more than 0.4 mm, provided that the structure is exposed to weather influences.
The width of the crack should not exceed 0.3 mm if the concrete base is located in an aggressive environment.
It is not recommended to allow the formation of gaps larger than 0.2 mm when we are talking about reinforced structures that are characterized by reduced resistance to corrosion.

Horizontal cracks with a small opening, which often appear in reinforced concrete columns, are also considered non-hazardous.

However, it is important to take into account that there are certain operating conditions under which cracking is not allowed at all:

if we are talking about reinforced concrete structures that constantly interact with liquids and gases (that is, they must be impenetrable and airtight);
when using structures that are subject to more stringent requirements for their durability.

Having determined the type of defect and the need to correct it, it is much easier to choose than to repair holes in a wall or any other concrete surface.

Cement mortars

These compounds are very popular due to their low cost and ability to repair minor shrinkage cracks in concrete.

Repairing a crack

Before you begin sealing, you need to check the crack itself for chips around it. If there are any, then in the near future they may turn into holes, so it is imperative to remove all peeling pieces of concrete. After this you need:

Perform jointing. To do this, using a chisel and a hammer, you need to walk along the entire length of the crack so that its depth is at least 5 mm. If necessary, you can use a spatula to create a depression.

Remove dust using a vacuum cleaner and rinse the resulting cavity with water.
Remove excess water and cover the crack with cement mortar (3 parts sand to 1 part cement with the addition of PVA). In this case, you need to ensure that the composition covers the entire space of the recess.
Moisten the poured cement with water.

Filling the hole

If a hole has formed in the concrete surface in which the reinforcement is visible, the defect can be repaired as follows:

Clean the hole in the concrete and treat its surface with an anti-corrosion compound.
Place pieces of steel wire about 4 mm in diameter into the recess.
After this, the recess is covered with a primer, applying it evenly over the entire surface. In this case, the thickness of the mixture layer should be about 3 mm.
Without waiting for the mixture to dry, fill the hole with a cement compound for sealing cracks in concrete and make sure that it fills the entire hole. If the hole is too deep, then cement is poured in several stages. In this case, each subsequent layer must be moistened with water from a spray bottle.
Level the surface with a lath (metal or wood), moving the tool from right to left.

After the mixture has hardened, excess cement composition must be removed with a spatula and the surface must be plastered. If the crack was too deep, then leveling is done using grinding machine.

Healthy! The cement composition must be poured with a reserve so that it is slightly higher than the floor surface. The mixture will shrink as it hardens.

After 24 hours, the concrete floor can be painted or any finishing material can be laid on it.

However, it is worth considering that such sealing of cracks in concrete will not provide a sealing effect and is not suitable for surfaces that have increased waterproofing requirements. In addition, the cement composition can be considered as a temporary solution to problems. Sooner or later the defects will appear again. If you want to “overhaul” the holes and avoid their occurrence in the future, then in this case you can repair the defects using resins, specialized repair compounds based on them, or sealant.

Long-term repair of defects

Deciding how to repair cracks in concrete long term, it is worth paying attention to this defect handling method. Resin and sealing mixtures based on it are suitable for restoring screeds, blind areas and various concreted areas or horizontal surfaces.

Repairing cracks in concrete using such compounds has a number of advantages. First of all, this is the low cost of the mixtures, as well as their quick drying. On the other hand, the resin allows you to securely fix the seams and keep them from subsequent expansion.

So, to eliminate defects you will need to prepare:

angle grinder and diamond-coated discs;
vacuum cleaner;
spatulas and a trough for diluting the composition;
primer composition for concrete;
Epoxy (base A and hardener B);
Fine-grained sifted sand.

Before you repair a crack, you need to clean it of dust and dirt. After this, we carry out the sealing in the following sequence:

We repair the crack. In this case, the width of the resulting recess must be at least 5 mm.
Using a grinding machine, we cut transverse seams in the concrete in increments of 400 mm (the length of the grooves is about 100-150 mm).
We remove the loose layer of concrete and remove dust from the surface using a vacuum cleaner.
We treat the surface of the defect with a primer, and fix the transverse grooves using repair brackets.
We prepare a solution from resin (base), hardener and sand according to the instructions on the packaging with the composition.
We fill the defect with the resulting mixture and quickly level the surface, since the setting time of the resin is only 10 minutes.

The best epoxy compounds

If speak about the best materials for repairing cracks in concrete walls ah and other surfaces, the most effective today are considered to be:

Domestic epoxy resin ED-16 and ED-20 costs about 2,000 per 3 kg. The hardener will have to be purchased separately (costs about 300-500 rubles).
Epoxy 520 resin from the Czech manufacturer Spolchemie costs 3,500 rubles per 5 kg.
German composition UZIN KR 416, which will cost 2,700 rubles per 0.75 kg.

Also very popular are compositions from Italian manufacturer Sika.

However, it is worth considering that this method of correcting defects is not suitable for processing holes that form in concrete foundations experiencing strong pressure from water. In this case, it is worth using a sealant.

Use of sealants and self-expanding tapes

It’s worth saying right away that this method of sealing defects is very expensive, so it is most often used when repairing concrete bowls of country pools. However, despite its high cost, the use of sealant and self-expanding cords has its own advantages:

the ability to process any type of defect;
complete tightness;
possibility of holding installation work in cold weather conditions.

To work, in addition to the standard set of tools, you will need:

mounting gun;
self-expanding tape or cord;
chisel and brushes;
sealant for concrete.

However, before covering up the flaw, you need to measure the dimensions of the cracks and purchase desired type sealant and tapes depending on this. For example, if the hole depth is 60 mm, then an 18 x 23 mm cord will do.

The next step is necessary:

Expand the cracks and remove dust.
Install the cord into the recess.
Fill the remaining space with sealant.
Smooth out the protruding compound using a spatula.

After completing the work, you won’t have to guess how to putty the surface or caulk it. It is enough just to apply the composition and smooth it out.

If speak about the best lineups of this type, the most popular are:

Domestic ELASTOSIL PU 20 costs 280 rubles per 600 ml.
The composition is from the French manufacturer Rubberflex, which today sells for 300 rubles per 310 ml.
PLOW tape Russian production costing about 260 rubles per linear meter.

Injection

Also, when deciding how to seal holes in a concrete wall in the most effective way, especially if not only a crack has appeared, but also water is flowing through it, you should pay attention to this method.

Injection technology involves the introduction of a special composition (polyurethane or epoxy resin, microcement or waterproofing mixture) into the thickness of concrete using special injection pumps that create strong pressure.

To perform such restoration of defects it is necessary:

Make holes in a staggered pattern on both sides of the gap.
Install packers in them (special tubes through which the solution is supplied, reminiscent of a dowel) at an angle.

Pour in the solution.
Pull out the tubes and cover the surface with the building compound.

So, we looked at how to fix a hole in a concrete wall yourself, but what if we are talking about aerated concrete?

Features of sealing cracks in aerated concrete

Cracks form in aerated concrete as often as in conventional cement-sand monoliths. To seal them, work is performed in the following sequence:

A layer of destroyed building material is removed from a wall or any other aerated concrete surface and cleaned of dust and dirt.
The gap is primed. To do this, it is recommended to use a 50% aqueous dispersion of PVA and water (1:3 ratio).
Cracks are sealed depending on their size. If the damage is single and its width does not exceed 0.4 mm, then the gap is widened to 10 mm and any building compound is poured into it (you can use cement or special adhesive for aerated concrete). If the width of the defect is up to 10 mm, then it is better to use porous adhesive composition and widen the gap to 20 mm. If a defect up to 20 mm wide appears, it is recommended to use an adhesive or cement composition, after adding coarse crushed stone from aerated concrete.

After completing the work, it is necessary to cover the treated surface with a sheet of plywood (secure with self-tapping screws) for 3-5 hours.

Cracks in the walls of a house, both inside and outside, are a common occurrence, and they appear according to various reasons, which we will look at below. You will also learn how to repair a crack in a brick wall concrete surface, cracks in drywall, or in a wall plastered with cement. Self-sealing cracks in brick walls is possible for every owner who is not afraid of work and has a minimum set of household tools.

Repairing cracks in brickwork

Destruction of brickwork can occur due to:

Soil shrinkage under the base of the foundation;
High groundwater level;
Shallow foundation deepening;
High load due to erroneous calculations;
Incorrectly prepared mortar and violations of construction technologies.

The area where cracking has appeared indicates the cause of the destruction. Thus, the appearance of cracks in the wall below means that the load-bearing loads from the pressure of the floors are calculated incorrectly. If cracks grow at the top of the wall, then most likely the foundation is shrinking.

Before you cover up the cracks in brickwork, it is necessary to monitor their condition - whether cracks are growing or not. This is done by placing plaster beacons, which are placed along the edges of the crack and hold the strip of paper. There are also special devices with measuring graduations. The crack is monitored for 7-10 days.

Minor repairs cracks in brick walls up to 0.5 cm wide are done this way: cover the damage with liquid cement without adding sand. Process technology:

The gap is freed from dirt and moistened with water;
The edges of the crack are expanded to increase the area covered by the solution, the solution is tightly packed inside;
The same solution, only with the addition of purified sand, can seal cracks 0.5-1 cm in size;

Large cracks (≥ 10 mm) must be repaired in several ways:

The destroyed local section of the masonry is dismantled and the brick is laid over a new one:
1. They remove the bricks, starting from the top rows, and put the bricks back “into the lock”;
2. The area of the new masonry is reinforced with any metal scraps that are suitable in size;
3. If it is impossible to disassemble the brick in the damaged area, cracks in this area can be repaired with a thick layer of cement-sand mortar, as described in point No. 2 above;
The crack is also wedged with T-shaped steel spikes, the edges of which are attached to the wall with dowels. With this method of repair, the same crutches need to be driven in from the inside;
You can repair cracks in brickwork using an installation tool. construction foam or sealant, after the substance has hardened, deepen the damage by 1-2 cm, seal the depression with cement mortar. The sealant is squeezed into the gap with a special construction gun;
An internal crack in the wall of a brick house is repaired as follows: first, the edges of the crack are tightened with a steel plate (plates), the edges of which are secured with anchors or dowels, then the area is covered with mortar;
If during the inspection of the building it is discovered that the wall is cracked due to shrinkage of the foundation, the base must be strengthened with an external concrete grillage along the entire perimeter. The grillage is poured into a trench, which is dug along the entire base to the depth of its placement.

How to repair cracks in a plaster wall

It would seem that a crack in the plaster is not a dangerous and insignificant problem, but this is not only a visual drawback. Not only does it suffer decorative coating, but also brickwork. Most often, plaster cracks on external walls, since their surface is affected by both moisture and temperature changes. Through such small cracks, water enters the bricks, and in frosty weather it turns into ice and destroys the wall.

From the inside, such cracks in the plaster are more like a spider's web - they are small and shallow, and appear due to incorrect proportions of the plaster solution or a thick layer of plaster applied at one time. That is, the technology here is clearly broken, and the problem can only be corrected radically - by knocking down old layer and apply a new one.

How to repair microcracks that may occur after wallpapering, plastering or painting walls? First you need to reinforce these damages with fiberglass mesh, glue a piece of glass wallpaper or fiberglass, and then plaster this place. The plaster mortar for these purposes can be external or internal, and the differences lie in the composition - the external mixture is based on the use of cement, the internal mixture uses lime.

When damage occurs on the plaster, how to repair microcracks? The repair solution can be industrial or homemade, and the repair technology is as follows:

Using a paint brush, the solution is applied to the area where there is a crack, and the surface is rubbed with a grater or spatula;
If the old layer of plaster was applied by spray, then to obtain the same effect after the repair, the brush is wetted in water, and then the plastered wall is moistened with a clap of a wet brush;
What to do if cracks appeared during the shrinkage of the foundation? Such damage can be repaired by deep impregnation with cement mortar. The dried solution is coated with dispersion paint.

It is also recommended to plaster a crack in a brick wall with the addition of astringent plasticizers - gypsum, alabaster, slaked lime.

The use of gypsum accelerates the hardening of the solution; in addition, the mixture with the addition of gypsum does not shrink during use. Adding lime is only necessary for repairing external walls, since lime mortar sets well only with free access to air flow.

Repairing cracks in drywall sheets

Reasons for cracking of plasterboard walls:

Improper installation of the frame and fastening of drywall sheets;
Incorrectly formulated putty solution;
High humidity in the room or temperature change.

Drywall as a building material absorbs moisture well; moreover, a wet sheet can be deformed, and after drying, retain a curved shape. A severely curved sheet or section of a plasterboard wall can only be replaced with a new sheet. And horizontal, diagonal or vertical cracks in a plasterboard wall of a house can be repaired as follows:

Fill the crack with putty or fill it with acrylic;
Plaster, and put a piece of fiberglass on top, apply putty on top, and cover the plastered area with a finishing layer of construction mixture.

Before repairs, the wall surface is treated:

The old plaster is knocked off, the area is cleaned;
The putty is prepared from a ready-made dry construction mixture in the following proportions: two parts dry mortar to one part water;
The putty layer should be no more than 2 mm; it is necessary to repair not only the cracked area, but also 5-10 cm of the adjacent surface;
If reinforcing mesh is used, it is not stretched over the damaged area, but driven into the gap and then plastered;
After the solution has dried (1.5-2 hours), the surface is sanded and cleaned of dust.

Repairing cracks in a concrete wall

Disproportionate concrete mortar in the manufacture of a concrete wall (slab) – main reason formation of cracks. When concrete is being placed into a form (formwork), it must be constantly compacted with a vibratory compactor, as a last resort- bayonet with a shovel or crowbar. The air remaining in the concrete not only weakens the structure of the material, but also promotes the movement of moisture into the pores, which in cold weather will lead to cracking of the concrete. But it’s not enough just to make the right solution and pour it - concrete must be constantly looked after, and especially at the beginning of the hardening process. Freshly poured concrete must be covered with a waterproofing agent so that moisture does not evaporate from the surface quickly and unevenly - if the moisture saturation of the concrete layers is not adequate, the upper, drier layer will crack, as the lower wet concrete will expand and put pressure on it.

Cracks most often appear on walls that are in conditions of contrasting temperatures, that is, outdoors. Freezing in winter, moisture in the cracks expands and causes the crack in the weak point of the wall to grow larger. If reinforcement is encountered along the path of such a gap, it begins to rust, which weakens the entire structure. Therefore, in order to avoid numerous repairs, the building must be periodically inspected for new defects in the walls in order to prevent their further development.

If a concrete wall cracks, it can be repaired by performing the following operations:

Using a hammer drill or a hammer and chisel, the crack is deepened and widened, the area is cleaned of dust and moistened. If there is open reinforcement in the crack, it is painted;
The proportions of the solution are 1:3, with the addition of Bustilat or PVA glue;
If the crack is deep, lay a reinforcing mesh and apply a solution, which is smoothed with a spatula;
After the solution has set, the irregularities are sanded with a grinder.

Cracks must be repaired in any case, even if they are small and short in length, since there is always a danger of their growth.

There are two main types of plaster: plaster for exterior and plaster for interior walls. Typically, both are applied in a layer 15 mm thick. To finish external walls, cement mortar plaster is used, and internal walls are often finished with a softer finish. lime mortar. Plaster is usually applied to a rough and hygroscopic base in one layer. However, to make this finish more durable, sometimes it is necessary to apply it in two or even three layers.

Working with spray-applied plaster requires special skill. In this case, the solution (for external walls it is prepared in the following ratio: 1 part cement, 3 parts sand; for internal walls: 1 part lime, 4 parts sand) is thrown onto the wall with a sharp movement of the hand so that it lies tightly on it “ pancake." If the throw is weak, the solution will fall on the wall in a lump that will quickly slide off it.

The plaster thrown onto the wall is smoothed with a wooden float, working it in lateral directions from bottom to top. Possible defects (depressions) are eliminated using a mason's trowel: the solution is rubbed into the plastered surface with a triangular trowel.

When finishing walls of a large area, so-called “beacons” are attached to them at a distance of approximately 1.5 m from each other (the easiest way is to use even wooden planks). The work associated with the installation of plaster beacons is perhaps the most important. After all, it is their front edges that will determine the position of the surface of the applied plaster, since the tool smoothing the plaster will move along these edges.

In this case, the wall is plastered in sections between the beacons, and after removing the beacons, these areas are sealed and leveled at the joints.

After removing irregularities, the plastered wall is treated with a trowel, making spiral movements with it. The applied plaster is allowed to sit for about half an hour and only then they begin to grout it - it will be easier this way.

On this base layer of plaster you can then apply the most different kinds plasters. In particular, spray the plaster with a brush or a special plastering machine. To get a smooth plastered wall, a layer finishing plaster smooth with a steel trowel or smoothing iron. In addition, after smoothing, sometimes they also apply to the plaster. gypsum plaster as a cover. Or, on the contrary, you can give the wall a rough, rustic look by treating the plaster layer with a mason’s trowel.

There are many ways to plaster masonry. But all this work requires patience and skill. Before you begin any of them, you should first practice at least a little on some area of the wall to be finished.

How to learn to plaster - we plaster the simplest wall ourselves - instructions

A novice plasterer will need the following tools and auxiliaries: a tank for preparing mortar, large and small wooden floats, a steel trowel, a triangular trowel, a plaster brush, a bucket for water, a brush, small trowels for grouting small depressions. You can prepare the plaster mixture yourself. However, ready-made plaster mixtures are also available for sale for both interior and exterior use, which simply need to be diluted with water.
The spray plaster is applied using a trowel, throwing it onto the wall with a sharp movement of the brush. In order for the plaster to adhere firmly to the wall, it must be of the appropriate consistency.
The plaster applied to the wall is leveled with a large wooden float, lightly pressing on it.
Depressions and cracks are sealed with plaster mortar, smoothing it with a triangular trowel. When finishing a section of wall close to external corner A board is attached to the adjacent wall as a stop-limiter for the plaster.
The plaster applied to the wall is treated with a wooden float, making spiral movements with it and pressing the entire surface against the plaster. It will be easier and easier to work if the plaster is allowed to dry a little.
Using a steel trowel, apply and smooth the finishing layer of plaster mortar onto slightly dried plaster. And here the tool is worked from the bottom up.
With a brush constantly dipped in water, the plaster that has just been applied to the wall can be treated with a “rustic” look.” In this case, the brush is not driven over the plaster, but only patted on its surface, which gradually takes on the appearance of spray-applied plaster.
The plastering machine is filled with liquid mortar. When the brush rotates, the solution is sprayed onto the surface to be plastered.
On top of the plaster on the interior walls, gypsum plaster is additionally applied as a covering. The latter is applied in a thin layer using steel smoother. Walls prepared in this way can be painted or covered with wallpaper. However, the covering is allowed to dry thoroughly beforehand.

SEALING AND REPAIRING CRACKS ON WALLS WITH YOUR OWN HANDS

Cracks not only spoil the appearance of plastered walls. If cracked plaster is not repaired in a timely manner, it can cause more serious damage to both the plaster layer and the brickwork. First of all, this applies to external walls, which are more susceptible to moisture and low temperatures. Through existing cracks in the plaster, moisture can penetrate into the masonry and freeze there. At the same time, the plaster will begin to fall off and the masonry will begin to collapse. Timely repair of cracks will not only put the wall in order, but will also prevent its further destruction.

Before you start renovating a plastered wall, you need to repair all the cracks and chips on it, since neither paint nor wallpaper will completely cover them.

The easiest way to repair plaster is with streak and shrinkage microcracks. In this case, it is enough to simply treat the damaged areas with a pound of deep impregnation, which, penetrating into the plaster, strengthens it. Old wallpaper and paint, of course, need to be removed before this. After allowing the pound to dry, the cracks are painted over with thick dispersion paint.

Cracks that arise as a result of internal stresses, or larger cracks formed during shrinkage of the structure, are repaired. When repairing external walls, only weather-resistant materials should be used.

When repairing concrete walls finished with cement-based plaster, special emulsions (for example, PCI emulsion), into which you just need to add cement and mix, have proven themselves well. The resulting mixture is applied with a brush to the cracked plaster.

The most difficult thing to restore is a plaster layer that is cracked as a result of uneven settlement of the building, which can occur for various reasons.

Cracks caused by settlement of the building are repaired. However, these cracks can appear again and again until the process of settlement of the building stops.

How to repair cracks on the walls yourself - instructions for beginners

Plaster that is cracked due to static stress and shrinkage of walls is repaired as follows. First, the crack is widened.
Then the surfaces of the enlarged crack are generously moistened with a brush or sponge. After this, rub the repair compound into the crack with a trowel or spatula.
Until the repair compound has set, a gauze strip or a special sickle tape is placed on top of it and pressed firmly so that its edges extend beyond the edges of the crack.
Seams between structural elements (especially if they are built from different materials) it is unlikely to be reliably sealed with plaster mortar. To do this, you need a sealant that remains flexible. But in any case, the seam must first be cleaned of any remaining mortar.
The construction seam is filled with a special silicone sealant, squeezing it out of the plastic cartridge using a gun so that the sealant penetrates into the seam as deeply as possible.
Immediately after filling the seam, the surface of the sealant is smoothed with the thumb, periodically wetting the finger in an aqueous solution of detergent.
Cracks caused by building settlement usually extend through the entire thickness of the wall. To accurately determine the nature of the damage, knock down the plaster in the crack area with a hammer.
Shaky masonry bricks are strengthened by filling the masonry joints with cement mortar. Of course, you should first remove the old mortar from the cracked joints. Reinforcing wire mesh is placed on the cleared area of the wall and secured with nails.
First, plaster is applied to the fixed mesh for rough leveling, and then finishing.
The applied plaster is smoothed with a trowel soaked in water, making circular movements with it.
After allowing the new plaster to dry, the repaired section of the wall is primed or applied with a suitable protective composition. This base is suitable for painting a wall or wallpapering it. In any case, the patched crack will not be noticeable.

Ladymisty 30ml Nail Extension UV Gel Polystyrene Construction Liquid…

89.17 rub.

Free shipping

How to fix a crack in a brick wall? Brick is the most common construction material, used for the construction of buildings. But its disadvantage is the cracks in the wall of a brick house that appear during operation.

Eliminating such a deficiency is not particularly difficult. In this case, you need to determine the reasons for the appearance of cracks and choose the right technological process, which is recommended to learn from this article.

What are the causes of cracks and their types?

Tip: To detect cracks in brickwork, you should visually inspect the entire house. Pay attention to the direction of the expansion of the split.

The direction of cracks is affected by the loads on the walls.

For example:

Expansion goes downward due to vertical load.
When the foundation subsides, the cracks expand upward.
Due to wear of the material, numerous cracks open closer to the surface.

Cracks can be:

Constructive. Such causes of cracks in brick walls arise due to:

error when calculating the depth of the foundation;
incorrectly chosen load on the walls;
failure to comply with house construction technology;
the brand of masonry mortar does not correspond to the current loads;
lack of wall reinforcement.

Temperature. Such defects are formed from:

freezing of the foundation;
temperature changes.

Shrinkable. Their reasons may be:

pit near the house;
the building is being erected on fill soils.

Deformation. Wrong material selected.
From wear and tear. All materials have a certain service life.

By appearance and depth of cracks are:

Vertical.
Horizontal.
Inclined.
Direct.
Curvilinear.
Walls that are closed or do not extend to the edges.
Through.
Superficial.

Based on the size of the gap, they are divided into:

Wide, more than one centimeter.
Medium, from 5 to 10 millimeters.
Small, up to 5 millimeters.

How to check cracks for stabilization of their further expansion

Advice: Repairing cracks in a brick wall should begin only after the process of its further enlargement has been completely stopped.

Elimination of cracks in the brick walls of a house is carried out after the final determination of the reasons for their appearance and the completion of the shrinkage process. To understand whether the cracking process has ended, you need to conduct a special tensile test.

This is done with:

Gypsum beacons.
Plate beacons with a special scale.

Stabilization can be determined:

Sticking paper on the crack.
Applying a cement strip.

After a certain time, the paper or strip remaining intact indicates that the cracks in the brick wall can be sealed. If you continue the deformation process, you must wait until it is completed. At this stage, there is no point in carrying out any repair work; the crack will reappear.

How to repair cracks in a brick house

Before repairing a crack in a brick wall, you need to prepare tools and materials.

They may be:

A small spatula for easy mixing of the solution.
Container for the mixture.
Construction trowel.
Hammer.
Brush.
Scarpel, for stone processing.
Putty knife.
Polyurethane foam.
Cement.
River sand.
Rolled metal.
Fittings.
Dowels.
Anchor bolts.

Depending on the type of crack in the wall of a brick house, the option of sealing it is selected. For shallow cracks up to 5 millimeters wide, a durable solution of cement or gypsum is used.

In this case, sealing the crack with your own hands is performed in the following sequence:

Conducted preparatory work. The cracks are cleaned of:

garbage;
mud;
dust.

The cavity is generously moistened with water and left to dry.
The crack is treated with putty or cement plaster solution.
Reinforced tape is laid.
A layer of cement mortar or putty is applied to the tape.

To seal cracks up to one centimeter wide, the instructions suggest:

Dismantle cracked areas of masonry.
Clear repair areas of debris and dust.
Re-prime the surfaces (see Why a primer is needed: technological nuances of finishing work).
Drill holes for dowels in increments of 25–50 centimeters.
Fix a metal mesh with mesh sizes of 5x5 millimeters on top with screws.
Cover the mesh with plaster cement mortar, adding a small amount of sand to it.
Finishing material is applied.

The sealing of wide cracks is carried out in the following sequence:

Cracked bricks and cracked bricks are removed from the outside of the wall.
The defect area is cleaned with a construction scraper to remove any dirt and dust.
New bricks are being laid on cement mortar.
This kind of crack can be eliminated using a metal anchor, as in the photo, which is a plate with two pins or anchors located on it.

Tip: Cracks more than one centimeter wide are critical defects in the walls of a house that require special methods of elimination.

To eliminate them you will need:

Clean the damaged area from contamination.
Fill the defect with polyurethane foam.
Leave until completely dry.
Trim the foam to a depth of two centimeters.
Fill the resulting depression with cement-sand or cement composition.
Apply finishing material.

If it is not possible to dismantle the cracked brickwork of a building, you can do this:

The repair site is cleared of debris and dust.
The cracks are sealed with cement mortar.
T-shaped strong anchors are driven into the cracks, necessary for fixation with dowels on both sides of the crack. They are attached to the surface of the wall of the building.

How to repair through cracks

To eliminate such defects, you can strengthen the walls.

In this case:

Preparatory work is carried out: damaged areas are cleaned of old coating, dirt and dust.
The crack is wetted with water and time is given to dry.
The gap is filled with cement mortar and small fraction crushed stone.
If necessary, steel linings are fixed with anchors and dowels.
Produced Finishing work damaged sections of building walls.

Through gaps can be eliminated using metal staples.

For this:

Prepared:

metal plates - two pieces;
bolts for tightening, they will be passed through the wall.

Tip: To prevent further opening of the crack, steel brackets should be driven into the wall on both sides. Bend their ends to the wall and secure with bolts.

Before fixing, the bolt holes are filled with cement.
Large defects can be eliminated by installing several staples.
The crack itself is sealed with cement in the same way as in other cases.

How to eliminate cracks in brick walls and dangerous cracks

For cracks that appear on the walls of external brick walls, a metal clip is used. Depending on the width of the wall, the dimensions of the cage and its design are selected. To eliminate serious cracks that threaten to destroy the house, metal joists are installed on both sides of the wall. This will allow the building to be covered with a powerful steel bandage.

How to eliminate foundation deficiencies

Cracks can often be caused by flaws in the foundation.

By strengthening the foundation, further formation of cracks and their spreading can be prevented.

For this:

A trench is dug along the area where the crack appears, no thicker than the monolithic base, but with a depth slightly below the edge below.
The crack site is cleaned, freed from poorly retained elements, cement mortar, and slightly enlarged.
The area is drilled for reinforcement vertically and horizontally.
The anchors are woven with reinforcement and welded. In this case, the distance between the reinforcement is from 0.6 to 1 meter, which depends on the size of the crack. The created structure will become a frame connecting the house with a new reinforced foundation.
Wooden formwork is being installed.
Concrete is poured.
Allow to dry for approximately 28 days.
A blind area is being made.

Paper beacons are used to check the elimination of the cracking process.

After the restoration of the foundation, the walls are repaired:

Destructions up to 5 millimeters are repaired with cement mortar, the edges are beaten, cleaned, and wetted so that they adhere well to the mortar.
Cracks larger than one centimeter are sealed with cement and sand in a ratio of 1:3.

If there are large gaps in brick walls, emergency measures will need to be taken:

The brickwork is dismantled from above, damaged parts are removed. New bricks are laid with a lock, reinforced with metal rods, profile corners or metal strips.
When masonry breaks, metal strips are taken, their ends are bent into the masonry and pressed out with bolts, anchors and screws.

Advice: If it is impossible to use such methods, crushed stone and cement should be poured into the gap. At a distance of approximately 25 centimeters on both sides it is necessary to drive in T-shaped anchors. The elements are connected with metal strips.

Deep cracks that cannot be completely sealed with cement are filled by injecting mortar. To do this, holes with a diameter of more than 25 millimeters are made in increments of 20 centimeters along the perimeter of the crack. A tube with a solution is inserted into the holes. Through it, a sealant is pumped into the gap with a pump or vacuum syringe, carefully filling the voids.

For very large cracks in brick walls, if the masonry is cracked through and through, repair work is carried out from the outside and from the inside.

Wherein:

The area is cleaned and its edges are processed.
The crack is deeply moistened and filled with crushed stone and cement.
If necessary, steel plates are installed, which are secured with dowels and anchors.
After drying, the wall is sealed with plaster or other cladding.

How to strengthen brick walls

Advice: If there are no results after repair work walls, it is necessary to partially re-lay them.

To guarantee the strength of a cracked brick wall, it is advisable to strengthen it from the inside of the building.

This means:

Sealing the crack.
Putting a lock or metal profile on it.
The lock is attached to the wall with anchors, and the gap is closed across it, which will prevent its expansion in the future.
Repairs can be made with metal staples; their ends should go into the wall to a depth of at least 1/2 the thickness of this wall, in which holes for the staples should be drilled in advance.
Within a day, such a repaired wall can be put into operation. But in any case, you cannot load it too much - the wall will only gain full strength in a month.

If the cracks appeared due to an improperly poured foundation, the best solution The foundation will be strengthened with an auxiliary concrete belt.

For this:

A trench is dug around the entire perimeter of the house with a depth greater than the depth of the foundation.
The auxiliary belt will be placed in it.
To prevent further cracks from forming in the masonry, the base is poured using the appropriate technology.

What kind of cracks there can be in brick walls, their cause, and how to eliminate them can be learned from the video in this article. Cracks in brickwork are very common. The cost of solving this problem varies, but it is worth getting rid of it immediately to avoid compromising the structural integrity of a residential building.

I saw several written requests in my mailbox, where people asked me to tell them why it was in the walls and how to seal them. It turned out that everything they knew and did before did not work. Not a single method saved them from new formations. So I decided to write this article.

I haven’t talked about this topic with anyone for a long time, and I came across similar work about a dozen years ago, so I decided to update my knowledge and see what great minds have come up with that’s new in this regard. By the way, we always try to give you the latest information so that you keep up with the times. After all, something new is often invented, and applying it is often cheaper and more effective.

Let's get to the bottom of the problem

Well, let's start by defining the types of cracks. Yes, they are radically different from each other, divided into two types. The first is erosion cracks, caused by a process called erosion, although weathering may also be involved. So, erosion is a process of destruction that is associated with time, with the influence of mold, precipitation, wind or thermal expansion.

For example, we have a wall that was plastered with ordinary cheap cement, and even in a 1/3 ratio. Yes, the plaster holds up and looks beautiful. But it absorbs moisture and crumbles due to insufficient molecular bonds. But as a result, water penetrates into it, washing away all our connecting elements from the top layer.

When the time of autumn rains comes, they abundantly saturate and saturate everything around with moisture. The wall does not have time to dry thoroughly before winter, and the moisture freezes, and at the same time it greatly increases in volume. Try typing in glass bottle water and place in the freezer. You will see that once it freezes, it will easily crack the bottle. And if it is a metal container, then it will simply bend or inflate.

So, the same thing happens in the thickness of the plaster, water tears it apart from the inside. Do you see how much there is? So, all these factors, of course, destroy over time surface layer more and more. And what is the result? That's right, microcracks appear. The length of each of them is approximately 1 cm.

If they are not sealed, then even more water will get into them, or some other factors will act doubly intensely and increase the cracked areas several times. If in this case you do not cover them up, then after some time such plaster will completely fall off.

In general, you understand, we have now described an example of an erosion crack on the surface of the plaster of a building. Exactly the same can be found indoors. For example, if the wrong composition of cement was selected, then it may not respond very quickly to thermal expansion and may also crack.

There is another type. For example, if we talk about a very old brick house, which was not finished with plaster, but simply a brick was laid under the jointing. Yes, here erosion, even over a long period of time, cannot do anything to brick, that is, to compressed and baked clay.

Most likely, erosion will wash away the suture cement, and as a result, small cracks in a brick wall. If the cement from the joints is washed enough so that the main load is removed from it, then where will it fall? Of course, it will either attack the remainder of the concrete in the seam, or it will move to a larger section downwards, and then overcome it too.

All this, it would seem, is nonsense. But tell me, what is the purpose of plaster? That's right - prevent harmful factors from reaching the main wall. And I’ll tell you that even plaster with minor defects can cope with this. The cracks that have appeared are the result of your savings, because the wrong type of cement was selected that was needed. Either you didn’t know about the existence of another, or you just saved money.

After all cement mortars there are any. For example, decorative, heat-resistant, structural, lightweight, dense, porous, astringent, tensile, protective-radiation, polymer, chemical, heavy and several dozen different ones!

Yes, in regular ones construction stores you won’t find them, because it is profitable for the buyer to purchase only one type, the cheapest, and sell it to you at the highest markup. But, as you can see, if you want, you can choose a special one for any type of work. Well, not about that now.

In general, the plaster described above copes with its task, that is, it protects the main walls from destruction. And if you saved on it on purpose or not on purpose, then be so kind as to patch it up a little, and everything will be fine. We will describe how to do this later.

Now comes the fun part. I am almost 100% sure that you asked for advice not because you need to fix a dozen tiny cracks, but because you have a real problem with the formation of significant cracks. If you have not small cracks on the wall, but large ones, half a meter or a meter long, and they arose not just on the plaster, but in the body of the main, that is, load-bearing, wall, then you do not have an erosion crack, but a real one deformation

Remember for the rest of your life, a deformation crack never just appears, and you will never eliminate it with any coating. If you have one, then you need to fight not with it, but only with the cause of its occurrence.

So, let's figure out what are the causes of deformation cracks and list them.

Excessive one-sided shrinkage of the foundation

The most terrible type of deformation. In addition, this is the most common situation, it occurs everywhere. If the foundation was not poured according to technology, if dozens of conditions for its pouring were not met, then it may crack. As a result, the wall located on it will also crack. In this case, a shear will occur - not a shear, but a shear - of the static loads, and the entire structure will begin to move relative to the axis, which will yield to this movement.

Yes, it's a little difficult to understand. Let's diagram what we're talking about:

As you can see, part of wall "A" begins to move. This movement can be either vertical or horizontal. In any case, this is an extremely serious building defect. And if such a problem arises, we are faced with global work.

Many people advise foaming the crack, covering it up, and that’s it. But if you think rationally, you can realize that on average square meter the wall weighs about a ton. Of course, there are 500 kg, there are also 5 tons - it doesn’t matter. So, part of the wall weighing 20–30 tons goes down, while also pushing through the foundation. It is simply unrealistic to solve such a colossal problem with simple putty. Well, never mind, more on this later.

Damage to the foundation due to damage to the blind area

The blind area is connected to the base and is an element that protects the foundation from water. So, if the blind area is damaged, water begins to flow into the foundation space. It liquefies the soil and accelerates shrinkage.

If the thickness of the freezing layer reaches the level of water in the foundation, then when it freezes, it similarly begins its destructive effect. And when destroyed, we get, again, the consequence that was described above.

Thermal expansion

This can also be a problem, but quite rarely. The atmosphere inside the room does not change quickly. The house is like a thermos in which the temperature is constantly maintained. Inside, it is almost equal to the temperature of the room walls. If it is -10 outside and +25 indoors, then constant heat exchange occurs. From heating devices to walls, from walls to atmosphere and vice versa. So, the temperature inside, as we know, does not change, and thermal expansion is either completely absent or extremely insignificant.

Now let's imagine a house that has had no window for several years. For example, at your dacha it was broken, but you didn’t see it or decided not to put it back in. So what happens? The weather outside changes very quickly. In the autumn-winter period, it often happens that during the day the temperature is +2, and at night it drops to -8. As you remember, our window is broken, and the temperature in the room is changing at exactly the same speed as outside.

The walls of the building, having heated up during the day, cool down very quickly at night, and vice versa. So they begin to play like an accordion: sometimes they expand, sometimes they narrow. Since the rate of temperature change is high, the speed of this “game” is also high. And concrete or brick walls- this is not an accordion, so they can’t stand it, they burst.

In this case, only the walls burst, but the foundation remains intact. Although it is difficult to eliminate such a malfunction, it is possible. At the same time, it is possible to make it as if it did not exist.

Design changes

These also cause deformation cracks. To help you understand faster, let's give an example. Let’s say you bought a house, and in the middle of the hall there is a column, and it’s like an eyesore. If you don't like it, kill me. Without thinking for a long time, you tear it down, and six months later you begin, perplexed, to ask: why are the walls cracking?

Well, how can they not crack or burst if you demolished the support beam, which carried the lion's share of the load. The walls took on a load they were not designed for and began to burst. Everything is simple and sad. If you have a similar situation, then now you have serious work ahead of you, which we will describe below.

Rotting, damage to stiffeners or support beams

Cracks can also occur for this reason. If, for example, you have a two-story building, and the span above the window was built using not a channel, but wooden beam, then when he can no longer bear the load, what will happen? That's right, at this point the wall will burst, or something even worse will happen.

The same applies to damage to stiffeners or concrete lintels. If, for example, you had a seismic beam in your apartment, but you didn’t like it and you demolished it without permission, get ready for serious problems and punishment, because cracks are now inevitable. And they will arise not only for you, but also for all your neighbors, who will definitely call the BTI.

Let's say you live in your private house, which you recently bought, you have one room upstairs that is empty, and you decide to put it there lathe. Yes, somehow you manage to get it in there, you are happy and everything is fine. And a month later you discovered that you had a finger-thick crack on your wall. Strange, yes, where did it come from?

Well, of course! You have placed a machine, the minimum weight of which is 3 tons, on an area of three squares. And the slab that took on the load began to put a huge mass of pressure on a section of the wall, which as a result could not stand it and burst.

We eliminate erosion cracks

Let's move on to the “sweetest” part of our story. I say this because everything is done extremely simply and does not require much effort. Understand that all your actions should be aimed only at preventing the damaging factor from entering the crack body, and nothing more.

If you pursue the goal of preventing their occurrence, then it is pointless; you will not be able to do this anyway. Perhaps you can treat the surface with a strengthening primer, but the effect of this is minimal. So, in order to eliminate erosion cracks, do the work in the following sequence.

Since you still have to worsen the visual condition of the wall by applying some other solution to it, leaving stains, then treat the entire wall with a strengthening compound. It won't be redundant. And if you don’t want to do this manipulation with the entire wall, then apply it only to the crack and, preferably, into its cavity too. This can be done with a syringe or sprayer, which, for example, you have left over from a window cleaner.
Dilute the solution, and it is better not to use gypsum-based putty or cement, but, for example, tile adhesive or a similar composition. Such products bond better with the surface, and in this case your putty will definitely not fall out of the wall.
We collect glue or some other solution into a large syringe or similar device and press it into the crack. Sometimes I even took a thick bag, poured a little glue into it, cut off a corner (a very tiny piece), and worked with it like a pastry bag. Just don’t press, otherwise the bag will split along the seam.
We fill the crack until our solution begins to bulge out of it.
We take spatulas and draw them from above, leveling our solution along the plane of the wall.

That's all. We carry out such manipulations with all our cracks. Upon completion of the work, it would be useful to prime everything again.

Elimination of deformation cracks

And this is the most serious, hard and thorough work. We have to spend a lot of money and work physically. So, information for general understanding. If there has been damage to the foundation, it is useless to build the wall; the foundation needs to be repaired. If there has been damage to the wall without damage to the foundation, then the wall must be sewn. If a seismic beam, stiffener or some other support was damaged, then it needs to be restored.

I won’t say much about the restoration of beams and other supporting elements. Remember the main thing: you don’t just have to restore this beam, weld it with reinforcement and concrete it. You will have to transfer the load that was there before to it, and this is done either molecularly or using jacks.

Now let's talk about the first two types of work.

Restoring the foundation

In order to do this, carry out the work in the following sequence.

That's it, the work is finished. Now, as soon as the old foundation moves even a millimeter, the new foundation will take its load; they are now tightly connected. All that remains for you is to plaster the crack. Only plastering should be done after at least two months. The entire structure must “play” and lie on a new foundation. If you plaster it the next day, you will see a tiny crack again in a month. This is exactly the distance that was needed for everything to rest on the new foundation. And if you did everything correctly, then you will never remember about it again.

This is how, friends, the cracks are eliminated once and for all, and not just covered over and forgotten. Understand that if you cover it up, it will do absolutely nothing. By the way, we once restored a building kindergarten, which burst during an earthquake. So, we measured the shrinkage by gluing a ruler to one side of the crack and measuring the discrepancy. It was a cosmic 2 mm per month, and this is critical.

We completely restored the damaged building in this way, and then the quality of our work was checked by gluing strips of glass to the control points of the cracks. None of them have burst to this day, since we always provided a guarantee, and every year we ask how our foundation stands there.

How walls are sewn

If there were cracks on the walls for some reason, you inspected everything and did not find damage to the base, then the foundation is intact and you will have to sew up the walls. So, necessary work depends on the type of damage, of which there are also two. The first is local damage, and the second is global.

In case of local damage, that is, when a small area is damaged, small and simple work is required. And if the damage is global, for example, your entire building bursts, then you will have to do something more complicated.

So, local view damage. These include small cracks one meter long, +/- 50 cm. These are sealed as follows.

Global damage. They are eliminated in exactly the same way as local ones. Only there, as you already understood, the crack is twice as large, and therefore we have to do something else.

You will have to throw several reinforcing belts over the entire building. It's done like this.

We mark lines around the entire perimeter, at a distance of 50 cm from each other. We make as many of them as we can fit. If the damage to the walls is not so severe, then we do it at a distance of 1 meter from each other.
Along the entire length of the marked lines we make grooves 20 mm deep.
We lay the reinforcement along the entire length in one groove. And we grab it there with a few strokes of alabaster or putty - it doesn’t matter what exactly, the main thing is that it holds.
And now the most difficult part, here you will have to work as a team. So, let's take the cutter. As you know, this cutting machine, operating on oxygen and propane. So, we take the cutter and warm up all our fittings. Let's do it as hard as possible. If its length does not exceed 6 meters, then great, you can use a cutter to heat it all up red-hot, this will be ideal.
As soon as the reinforcement has turned red, and it must have a diameter of at least 16 mm, then we grab the other two segments close to the wall from both edges. And they didn’t just stick it with slag from the electrode, but made a high-quality, solid seam. Because we are making a tense tension coupling, and it will be constantly under load.
We move on to heating the next one and repeat the same operations.
Once all the belts are welded, we plaster them.

Well, in the end, as soon as the metal cools, the entire circuit pulls our house together with tremendous force. By heating the metal, the molecules expanded and the length of the reinforcement increased. Then she returned to her previous position, only there she already had points of support - other reinforcements, which were all pulled together, as if with a noose. And now your walls will never crack again; they will be constantly rigidly restrained by reinforcing belts. It's like a woman's corset tightening her waist.

Well, friends, as you can see, everything is not as simple as you expected. In another article we will tell you how such serious problems could have been avoided. Because prevention is always easier than correcting something that has already been damaged.

I hope you found our story useful. I want to tell you finally that our goal was to write an introductory article, not rigid technical literature, so it should not be relied upon as instructions for use. And as you understand, only you are responsible for all actions you take. Therefore, approach all work wisely and carefully, and you will never have any problems. Good luck!