Causes of moldy walls
1. External rainwater seeps into the room, causing moisture in the walls. The baffle under the balcony window (mostly made of prefabricated floor slabs, so cracks are prone to occur at the junction of their junction with the wall) and the wall, or poor window sealing performance may cause external rainwater to seep into the room.
2. The drainage pipe or heating pipe leaks, causing the wall to get damp. Over time, the wall will become moldy.
3. The wall insulation is not done well, resulting in a large temperature difference between indoor and outdoors. In this way, the water in the indoor air will condense onto the wall after it is cold, causing the wall to be wet.
Simple treatment tips
1. When mold spots appear on the wall, you can first use a (dry) toothbrush to brush away the mold stains, and then gently wipe them with a soft cloth dipped in alcohol. This can dry the wall and prevent mold from growing.
2. When the mold is not too serious, it is enough to use 80% alcohol to wash the wall. Pay attention to ventilation when cleaning and wear protective gloves, masks and glasses. In order to avoid mold again, pay attention to completely drying the wall, eliminating the causes of mold, and properly heating and ventilation.
3. Add bleaching water (powder) and pour water into a spray bottle at a ratio of 1:99. Spraying it on a moldy wall can immediately solve the problem of mold on the wall. Wipe the wall with a rag; then wash it with clean water, and apply anti-mold paint after the wall is dry, which will prevent moisture for a long time. In addition, there is also a convenient household waterproof repair agent on the market. It only needs to spray it into the gaps in the leaking wall and floor like insecticides, which is very convenient to operate.
4. During wet weather, try to open windows as little as possible. In addition, try to make the walls dry. In humid weather, you can use dehumidifiers, air conditioners, and fans to absorb moisture from the walls. Once the wall or furniture has water vapor, it should be wiped immediately with a dry rag.
How to prevent moldy walls
1. Open the windows frequently for ventilation, or turn on and change the fan to keep the indoor air circulating.
2. The best way to prevent mold from growing on the wall is to prevent condensation on the wall. In the northern region, when room temperature is 18 degrees Celsius and relative humidity is 60%, any object below 10.1 degrees Celsius will condensate.
3. Purchase indoor desiccant and as for indoor use, it can effectively remove indoor moisture. After the active ingredients of the desiccant are used up, they need to be replaced in time.
4. There are three reasons for wall condensation, design, construction, and use. The design reasons include: although the wall meets the moisturizing requirements, the beams, plates and columns have not been moisturized; the heating technical measures are not taken, and the radiator is improperly arranged; the convex corners and special columns on the windward surface of the exterior wall have not thickened moisturizing layers, resulting in the insulation effect not meeting the standards, etc. The construction reasons include: the insulation material does not reach the thickness specified in the design; it is strongly cracked and air-permeable; and no moisturizing and sealing treatment is performed between the joints between doors and windows and walls.
In response to the above problems, we should solve the problem by adding insulation layers, replacing the original insulation materials with high-efficiency insulation materials, and moisturizing and sealing treatment for ventilation. For condensation caused by improper use of the user, excessive indoor humidity should be avoided. As long as it is designed, constructed and used as required, the problem of mold on the wall can be completely avoided.