How can we find out the cause of cracks in the wall?

The construction quality problem is also caused by the developer and the construction unit, the construction unit in the construction materials, the construction process, the technical links are not strictly operated, and the developer intervenes to reduce costs. However, if it is caused by quality reasons such as foundation subsidence, if it is only a crack on the surface of the paint film, you can use fine sandpaper to polish the crack off, choose the same color wall paint, and repaint it.

Process: Wipe the cracks with a dry cloth first, paste the tape on the cracks, press the solid, and be sure to close all the cracks. After pressing the top layer of plastic, the acrylic tape is transparent, you can see the cracks at the bottom, the wall or column section at the end of the supporting beam or roof truss has multiple vertical cracks due to local compression, or the crack width has exceeded 1mm.

If one of the above phenomena occurs, it should be assessed as a danger point. <>

It's very simple, let's talk about the practice of repairing houses at that time. Because at that time, it was a practice to repair a house, the foundation was dug grooves, and the better ones were cement mortar to pile up boulders. Due to the temperature, cracks appear in the thermal expansion and contraction of the wall.

This is just like a thing, hot and cold contraction, although this metaphor seems weird. Caused by factors such as low mud marking, poor river sand quality, etc. The solution can be based on the location of the floor to assess the size of the crack to judge how to deal with the crack, the professional and technical personnel of the appraisal department, to the scene to carefully inspect, measure, compare, in a small number, the evidence support, after the cause of the folding, the cause of the result, in order to identify the problem of the crack in the house.

The foundation is sinking, or there are quality problems, cutting corners, shoddy and many other reasons. There is also an impact on whether the house is a frame structure or a poured ground circle beam, and the foundation is not firm. Maintenance, compensation, adjustment of the house, etc., the Quality Supervision Bureau only puts forward opinions, and does not care about coordination, so many things need to be discussed with the developer yourself.

It may be that it is too hot in the room, so it is causing too many cracks. It is possible that the walls at that time did not dry after scraping the cement, and then cracked when it was hot. It may be that the quality of the brush is not good.

The cracks on the wall surface caused by the cracking of the wall paint layer are mainly caused by the poor quality of the wall paint products and the improper operation in the construction process of the wall paint. The temperature is too low to reach the film-forming temperature of the wall paint and cannot form a continuous coating film, resulting in cracking of the wall paint.

Cracks in the structural layer of the wall itself can also lead to cracks in the surface wall. There are two situations, one is that the original wall itself has cracks, and no appropriate treatment measures have been taken in the later decoration process; Second, the original wall was decorated without cracks, but cracks occurred in the later stage due to uneven foundation settlement and large temperature changes.

Causes of Exterior Wall Cracks The causes of exterior wall cracks are:

Cracks in external walls caused by uneven settlement of foundations;

shrinkage cracks, which are the main cause of cracks in concrete walls;

Temperature cracks, which include cracks caused by changes in the temperature of the wall itself and cracks caused by the temperature difference between the roof and the wall.

2.Treatment measures for cracks in the exterior wall Cracks on the concrete wall, in addition to taking corresponding remedial measures from the structural consideration, from the perspective of indoor seepage, the necessary waterproof treatment should be carried out to prevent rainwater from seeping into the room along the cracks.

1) Epoxy resin sealing method. During treatment, epoxy resin is injected into the crack with a low-pressure injection device to close the crack and there are no obvious traces after repair. This is a local repair method and is suitable for when the crack is narrow.

2) Groove sealing method. When processing, you can first chisel a U-shaped groove along the crack position, 10-15mm deep and 10mm wide, and then clean the groove. Coated with a base treatment agent, sealed with synthetic polymer sealing material, and smeared with polymer cement mortar on the surface.

This is a partial repair method that is suitable for situations where the crack width is large.

3) Mixed treatment. Inject epoxy resin into the crack area, or use the groove sealing method to treat the partiality (or comprehensive) along the treatmentAcrylic waterproof coating film can also be sprayed with hydrophobic materials such as silicones.

There are many reasons for cracks, and it is really difficult to tell, but there are some ways to tell. Small cracks are not listed for the time being, but large cracks have the following possibilities. One is a 45-degree oblique crack, which runs from one end to the other, which is usually a shear crack under compression.

The other is at the edge of the window, which is an inverted figure from the edge of the window, or a positive figure downward obliquely, which is usually a settlement crack.

Most of the cracks in the wall are caused by the settlement of the foundation, and the height of the floor and the size of the cracks determine the reinforcement problem in the later stage. Hope, thank you!

If the cracks in the filling wall are generally caused by non-standard planting bars, the plastering is not caused by hanging nets, and the load-bearing walls are caused by uneven foundation settlement!

There are many reasons for cracks in the wall, which depends on the direction of the crack and the bearing degree of the foundation to judge the cause of the crack.

If you want to find out the real cause of this situation, only a professional can find out.

Temperature-induced cracking.

Caused by subsidence of the foundation.

Something went wrong structurally.

Roadbed, temperature changes, raw materials. When the wall is cracked, we can use a certain method to do a good job: brush 108 glue at the gap and paste a glass cloth or cowhide sticky note.

Scrape 821 putty powder 2-3 times to scrape flat with the original wall, and then polish it with sandpaper after drying. Use a putty powder knife to scrape out the total width of the gap, and scrape off the figure-of-eight, the outer width and the inner narrow. Use plaster block powder to add trouble gaps, fill the deep depth of not less than 30-40mm, do not need to be smoothed with the wall, lower than the wall.

Adjust the wall emulsion paint, brush the sample first after the architectural paint is adjusted, and compare the color of the wall paint with dryness.

The color is close, the color cast is not large, and then the wall is painted. There are about 5 reasons for wall cracking: the first is that there are gaps in the insulation layer of the original house, which causes the wall to crack after decoration; The second is that the repair and brushing of the wall after slotting is unreasonable, resulting in cracks in the wall; The third is that the preparation of concrete is inaccurate when batching putty, and it is very easy to crack when the preparation is high; The fourth situation is that the preparation of wall putty is unreasonable or uneven scraping.

The fifth is that the preparation of wall paint and water is not suitable, and the above non-standard use will cause the wall to crack.

If the ambient humidity is very high, it will dry slowly and endanger the progress of the project, and may also endanger the quality of the brushing. If it is too dry, it will dry too quickly, and cracks may occur. If you are in the dry season, you should pay attention to fire prevention, because the material is more flammable and explosive.

The cracking of the cement in the wall is due to the fact that in the case of plastering cement plaster, the concrete is relatively small. Cracks caused by concrete and bricks not being thoroughly bonded.

Before the batch of putty, once the cement is found to crack. Then the first thing is to brush the wall solid adhesive on the wall and then hang the label, so that it is not easy to crack. The junction between the Xinche wall and the original structure wall and the position of the working handover between the wall and the concrete wall are very easy to cause gaps due to concrete cracks or different convergence of materials, and the gaps will cause corresponding tensile force in the case of cause.

At this time, the overall surface layer of the wall is attached with steel wire mesh to resist the tensile force and avoid cracking.

The reason for the cracks in the wall is generally because the surface treatment is not in place when the wall is painted, the primer is not fully dried, etc., and after a long period of use, the materials at different levels are misaligned due to the principle of thermal expansion and cold contraction, and they will crack. To deal with more serious and large cracks, it is recommended to scrape off the materials at the cracked position, redo the wall painting, and strictly use compliant materials and standardize construction. If it is only a relatively small crack, you can also buy a special wall joint repair agent, add a reserved topcoat, and fill the crack to repair it.

1. First sprinkle some water on the wall, and then remove it after it is wet, which will save time and effort, remove the wall skin to expose the cement mortar wall or putty layer, and then coat the interface agent on the wall, pay attention to apply evenly, for the cracks, special treatment should be carried out, and the cracks should be pasted with kraft paper tape and white latex to prevent continued cracking.

2. Next, it is necessary to apply and scrape putty powder, it is recommended to choose putty with high particle fineness and hard texture, of course, you can also add a certain amount of white latex to improve the hardness of the putty, and after it is dry, it also needs to be polished on the wall, so as not to have too much dust and affect the adhesion of the paint.

3. Finally, paint on the wall, it is recommended to put more water when modulating, so that the painting is more uniform, and at the same time ensure that each place is brushed during construction, so as to ensure the later construction effect, after the primer is dry, carry out paint-free painting, do not add excessive water, and the hair of the drum should not be too short, but it must be fine.

It may be that there is a problem with the decoration, or it may be caused by moisture, and it is necessary to determine what causes the cracking, and the net can be repaired.

Generally speaking, there are many reasons for wall cracking, the common ones are wall settlement or displacement, the splicing of the old and new walls, and the joints of the decoration ceiling.

Cracks in the wall are a situation that we often encounter in our lives, do you know what are the reasons for cracks in the wall? I think it is mainly caused by the settlement of the house or the deformation of the gypsum ceiling, today I will introduce the method of repairing the cracks in the wall, I hope it can help you!

1. The reason for the cracks in the wall.

Sometimes, many houses have no problems with the original walls, or have been treated accordingly before painting, but after renovation, cracks will gradually develop over time, why is that? In fact, the reason lies in the almost inevitable settlement of houses. There are two kinds of housing structure problems, one is the settlement of the house, and the other is the deformation and settlement of the gypsum ceiling.

1. Housing settlement.

Housing settlement is mostly caused by uneven settlement of the foundation, which is common in old-fashioned multi-storey apartment houses. Specifically, the surface of the wall shows a 45° direction crack. The top surface mostly runs through the east and west ends.

In addition, if the old apartment is a liquid stool structure, cracks often occur at the junction of the two slabs. Generally, the cracking situation is different, and different treatment measures need to be taken to repair the crack and prevent future wall paint cracking.

2. Deformation and settlement of gypsum ceiling.

Another common cause of wall cracking is the settlement of decorative elements such as suspended ceilings. One of the common ones is the deformation and settlement of the ceiling of gypsum board. Gypsum board ceilings are generally constructed using two processes.

One is the use of wooden keel, due to the natural lack of stability of wood, generally poor treatment or construction is not in place will cause thermal expansion and contraction caused by surface deformation, the other is light steel keel, sometimes the decoration company in order to save materials, intentionally increase the keel spacing, resulting in gypsum board settlement in the future.

Second, the wall crack repair method.

1. Buy elastic putty.

At present, there is a kind of "elastic putty" on the market**, which can be directly selected when decorating the wall to make up for the problem of wall cracks. However, the elasticity of this putty is not very large, and if it encounters a crack with a relatively large area, it will not work.

2. Cement sand repair.

If the depth of wall cracks exceeds 1cm, cement mortar is preferred to repair wall cracks.

3. Brush adhesive patches.

If the cracks on the wall are relatively small, you can directly take the steps of brushing glue - sticking cloth - making putty. Before brushing, the wall base at the cracks in the wall is cleaned, and a layer of newspaper or good cloth is pasted, and the tension of paper fiber or cloth fiber is used to ensure the integrity of the latex paint.

1. After the completion of the house, various pipelines are buried through the wall or other behaviors that change the use of the house, which destroys the integrity of the wall, reduces the bearing area of the wall, and weakens the bearing capacity of the wall, thus causing cracks in the wall. This kind of crack must be repaired with cement mortar in time.

2. The crack caused by the uneven settlement of the foundation, this crack is generally an oblique crack, which develops from the bottom to the top, and the crack goes to the depression. The cracks caused by the uneven subsidence of the foundation do not cause the strength or stiffness of the wall columns, and are repaired with cement mortar after the settlement is stabilized. If the stiffness and strength of the wall column components and the house structure are sufficient, then the wall cracks caused by the uneven subsidence of the foundation do not need to be reinforced, as long as the cracks are repaired.

3. Temperature splitting. This type of crack is the most common type of wall, located at the junction of different materials, and occurs due to their different properties of thermal expansion and contraction. This kind of crack only affects the appearance of the interior of the house, does not affect the safety of the house, can be pasted at the crack non-woven fabric, installed steel plate mesh or mortar to plug the joint, and then used paint to repair.

Cracks caused by temperature changes are difficult to repair, but there is no danger of the house collapsing and carrying skin. In order to avoid the occurrence of such cracks, it is necessary to solve the problem by solving the difference between the line swelling of the two different materials of the roof and the brick wall. Generally, the common method is to do a good job of roof insulation.

4. The quality of masonry construction is poor, the ash is not full when the wall is built, the thickness is uneven, the assembly method does not meet the requirements, etc., when the brick wall is built, the bricks are not wet, and the dry bricks are used on the wall, etc., which will reduce the bearing capacity of the masonry, so that the wall will have cracks in the future.