On the subject of untouchable wallpapers and tiles.
Parents in an old and already almost completely rebuilt private house decided to repair the ceiling in a large room. They removed from the ceiling a faner, and underneath it - several layers of geographical wide-format school maps. Moreover, they were stiffened intentionally, and in some places also nailed for reliability. They wiped and wiped it for two weeks. Probably the house would have collapsed, and the ceiling remained whole.