After the water pipe is buried in the wall, a groove larger than the pipe diameter should be made. The groove should be plastered to make the pipe smooth, and then the groove should be painted with waterproof paint for effective waterproof treatment. For the floor of kitchen and toilet, the floor drain with slope direction must be adopted, so that the drainage can be more smooth and water can not accumulate at the same time. At the same time, try to avoid changing the location of existing drainage and sewage pipes and floor drains when decorating. When making a washbasin, in order to prevent the sink of the washbasin from splashing on the wall nearby during use, if there is no protection of the waterproof layer, the wall will easily become damp, and even mildew may occur in long-term use. Therefore, when we lay tiles on the wall, we must first do a good job of waterproof treatment of the wall in advance, For some light-weight walls that are not load-bearing walls, the waterproof layer should be at least one meter eight high, and the waterproof position should also be one meter eight high on several walls that are close to the bathing position. If conditions permit, it is better to waterproof the entire wall of the toilet.