The white plaster walls turn black and peel after a while, what causes it?

Most people may not know that the alkali return of cement walls is actually mostly related to the damp environment. Because of the alkalinization caused by the evaporation of too much water, if it is not treated well, wait until the putty is scraped.

After the alkaline and salt substances in the bottom layer are precipitated, it will lead to the quality of these paint problems such as the white wall paint peeling off.

Causes of mold on the walls.

1. External factors: excessive humidity; Back to Nantian.

It is a phenomenon of weather resurgence, in which the excessive concentration of moisture in the air will condense and produce water droplets on the surface of an overly cold object, such as wall paint. When water vapor adheres to and infiltrates the surface of the wall paint film for a long time, it is easy to induce mold on the surface of the paint film. Generally, at this time, there are three places where mold is most likely to appear due to excessive humidity, namely the ceiling, the area near the water and the dark corner.

When ventilation is poor or the temperature is low, mold is more likely to appear.

2. Internal factors: the quality of wall paint is not up to standard; The antibacterial and anti-mildew performance of the coating product itself is poor, and water vapor can easily penetrate into the inner layer of the wall, resulting in the growth of mold. Improper operation in the construction process is also easy to cause mildew in the paint film in Huinantian, such as:

Excessive dilution of paint, application when excessive humidity, etc.

3. When the wall has mildew, you can use a toothbrush to brush away the mildew, and then gently wipe it with a soft cloth dipped in alcohol, which can dry the wall and prevent bacteria from breeding.

4. Pour bleach and water into a watering can at a ratio of 1:99 and spray it on the moldy wall.

5. Wipe the wall with a rag and then rinse it with water, and brush the anti-mildew paint after the wall is dry, so that it can be moisture-proof for a long time. There's also a convenient waterproofing remedial on the market that can be sprayed on cracked wall crevices.

Generally, this situation often occurs after the bathroom re-builds the light wall, the light wall partition wall of the bathroom must be waterproof, and the waterproof height must be 2 meters, otherwise the water vapor is easily absorbed by the light wall, and it will penetrate into the wall after a long time, making the wall moldy.

The first is that the wall was not treated well before scraping the putty, the original wall skin was not scraped off and not dried, and the primer was not brushed; the second is that the quality of putty powder is secondary; The third is because the family is more trendy.

The white ash wall will turn black and peel after a while, because the main chemical components in the white ash and the oxygen in the air have a chemical reaction and are oxidized, and the peeling is caused by the dampness of the wall.

The peeling of the white ash wall may be due to the unevenness of the wall, or it may be because the wall is damp, and it is not stirred evenly when painting, which will lead to peeling.

1. Use a shovel to peel the wall surface due to moisture to the cement layer, clean up the dirt and dust on the construction surface, and keep it clean and dry.

2. After that, the separator is applied to the cement surface 2-3 times, with an interval of about 3 hours between each pass, and the separator can play a role in preventing moisture and alkali to prevent the problem of damp alkali in the future.

3. After drying every other day, use water-resistant putty paste to repair the wall completely, and after 4-6 hours of drying, use sandpaper to polish the wall flat.

4. After the putty paste dries the next day, clean up the surface dust, paint latex paint 2-3 times, with an interval of about 3 hours between each time, and paint latex paint to make the wall smooth, white, and have no dust effect.

Answer 1: If the wall is damp and peeling due to rain, the peeling wall should be repaired and the interior should be dehumidified. If the peeling is severe, you need to shovel off the wall, treat the base layer, scrape putty, and brush the primer and topcoat. 2. Before the formal construction, it is necessary to check the firmness of the wall to ensure that the cement mortar on the wall is smooth and firm, so that the subsequent construction will be safer.

If it is found to be loose after inspection, it needs to be replaced to avoid unnecessary leakage. 3. Before the formal construction of the wall, the surrounding wall should be protected, so that when applying putty and paint, it will not cause damage or scratch to the surrounding foreign objects. Scraping the wall or scraping the wall to repair it later requires more time and economy.

During the drying process of the wall, try to open the window for ventilation and natural drying. Do not turn on the air conditioner to speed up drying, so as not to cause cracking of the wall. Preparation before putty:

Before applying putty, check the flatness of the wall. When the wall is not smooth enough, it should be leveled, smoothed, and then painted with putty. If the economic conditions allow, it is recommended to brush the RCC interface agent on the wall, and then start to apply putty powder after it is completely dry, so that the wall will be firmer and not easy to peel or peel off.

When brushing putty, it is recommended to brush it twice as much as possible, and the interval between the two times should be longer, so as to ensure a better putty effect.

How to deal with the peeling and white ash of the wall: 1. First of all, it is very important to choose high-quality materials. When decorating the house, we try to choose high-quality wall paint, to a large extent, to prevent the phenomenon of wall peeling, so when we choose materials, we must buy through formal sales channels, and choose qualified products, especially paint.

2. Secondly, it is very important to paint the wall and lay the foundation. The walls of a new house generally only need to be sanded with coarse sandpaper and painted according to the normal procedure. The walls of old houses will crack and peel, so when painting the walls, we must pay attention to the grassroots treatment.

3. Finally, it is necessary to strictly control the construction process. In order to better prevent cracks in the wall, it is also necessary to strictly control the entire construction process. There are many details that can only be done best if you personally stare at the painter.

Blackening of plastered walls is caused by a variety of factors. First of all, the blackening of the wall may be due to the wall absorbing too much moisture, causing mold and algae to bloom. This usually happens in damp and unventilated rooms, such as bathrooms and kitchens.

If this happens, the walls need to be cleaned and disinfected in time to prevent algae and mold from growing back.

Secondly, the blackening of the wall may be due to surface contamination. Walls can be exposed to airborne contaminants and dust, which can form a layer of black mold on the surface of the wall. In this case, cleaning and coating restoration are required to regain a smooth, uncluttered appearance of the wall.

In addition, the blackening of the plastered wall can also be caused by the use of unsuitable paints or materials. If the wall is covered with low-quality paint, the surface will be dismantled or untreated after years of use, and it will feel like it will shrink or crack, making the wall difficult to clean and easy to stain. At this point, it is necessary to recoat and waterproof.

In short, although there are many reasons for the blackening of the plastered wall, in daily maintenance, good ventilation should be maintained to avoid a series of factors such as excessive humidity and pollution. At the same time, you should choose materials that meet the requirements for construction, maintain and protect the wall to keep it dry, clean and beautiful.

1. The ash on the white wall may be that the construction of the base layer of the wall has not been cleaned, in this case, the base can be re-treated, and then painted with latex paint, and sandpaper sanded after drying. 2. When scraping the large white wall, we must master the correct construction method, such as scraping putty first, then polishing, and finally painting, so as to ensure the final effect of the white wall. According to professionals, many construction workers will save the polishing link in order to covet aspects, but this is not right.

1. Because the paint needs to be completed after a period of time from construction to complete drying, in order to ensure that the construction quality is not affected, after the completion of the construction, before the white is completely dry, it must be maintained for a period of time. Take the spring another wheel code, because the hardness of the big white wall is low, so pay attention to avoid bumps in the later stage, so as not to leave traces that are difficult to recover.

2. If there is only one point of ash, and the range is relatively small, you can use decorative supplies to cover the place where the ash is dropped, and try not to touch it. However, if the scope of ash is relatively large, or the ash is more serious, then it is necessary to remove the existing white wall, then clean the base surface, apply a layer of interface agent, and then scrape putty again and paint latex paint.

Dust and black spots on the wall are caused by the resurgence of moisture on the wall.

Solution. First of all, the wall should be cleaned, free of floating ash and loose faults, and kept dry.

Use the sealing curing agent material and apply it directly to the ash wall with a roller, which needs to be applied several times, and the flatness will not change after painting. The material effectively penetrates into the interior of the wall and reacts with the internal output to form a hardened layer, increasing hardness and improving wear resistance.

Specialized building materials factory shop.