First, mildew, moldy time in 2-3 months, you can use a wet towel to wipe the moldy point, a lot of mold first deal with; then the fungicide sprayed on the moldy place of the wallpaper, kill the wallpaper On the mold, after drying and drying, mold treatment, a small area of mold can be basically eliminated. Repeatedly spraying the anti-mold agent several times after drying can effectively prevent the wallpaper from becoming moldy again.
Second, the moldy area is larger, the moldy spots are more serious, and the wallpaper is torn off again, the moldy spots on the walls will be removed (if you can't afford to re-treat the walls), re-stick the wallpaper.
Third, the lower part of the window sill, or the external wall of seepage causing moldy, will generally be very soft wall foam, you need to remove the wall grassroots, re-putty putty, brush base film and paste wallpaper. These processing skills need to be completed by a professional wallpaper master.