· Two types of wallpaper thickness: Duplex (consist of two layers compressed by each other) and a symplex (single -layer and thin). Duplex wallpapers are strong enough and have soundproofing properties. The special composition with which the duplex wallpaper is covered, protect them from burnout and increase moisture resistance. The crushed wood waste adds to some wallpapers, which makes wallpaper similar to Japanese paper. Wallpaper covered with latex are perfect for the kitchen and hallway, t. To. have high moisture resistance and withstand up to 20 moles.