If the old wall has peeling or cracks, you can't brush latex paint directly. Use professional tools to level the wall first, and ensure that the wall is free of floating soil and smooth, and then blow putty, or you can clip a certain amount of white latex.
Usually it is leveled twice, and after the putty is completely dried, it is smoothed and polished with fine sandpaper. If the original wall is latex paint, the foundation strength is good, and it can be brushed directly after simple nap repair.
Extended data
Common problems in construction
First, the wall cracks: This phenomenon is the most common, and the specific reasons depend on the situation. If it is GRC light partition wall, crack prevention treatment should be done at the joint. Glass fiber cloth or kraft paper is generally used, and the partition wall is prone to small cracks due to its own characteristics.
Therefore, in order to ensure that there are as few cracks as possible in home decoration, it is best to stick glass fiber cloth or bean bag cloth all over the body. In the case of load-bearing wall or solid wall, the reason for cracks may be that the construction putty is too thick or the interval is short, and the putty is not dry. In this case, it is more common to transform old houses into three links and one leveling.
2. Uneven wall color: mainly because of different colors, the grassroots has not been handled well. This situation must be covered by scraping putty or brushing primer once. In addition, when purchasing materials, we should pay attention to the same manufacturer, the same variety and the same batch number, otherwise there will be color difference.
Third, the surface is rough: the main reason is that the grass-roots treatment is not clean, the brush has sand, debris or the operating environment is not clean. Preventive measures include cleaning the basic treatment, cleaning brushes and dust-proof environment.
4. Peeling: The main reason is that the foundation is too smooth or greasy. The preventive measure is to clean the bristles of the base with a steel brush, and the oil stain is decontaminated with a solvent.
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