Before we purchased our house, the previous owner "remodeled" the master bathroom. They covered with cement and low-end Lowe's tile red oak hardwood and mid-century tile from 1957. *Gasp* What kind of soul-less imbeciles DO such things?"No need to sheetrock the hole we just punched in the wall guys. We'll just cover it by hanging this mirror over it!" The grey square in the middle is the back of the hall bath mirror hanging over this huge hole we discovered in our wall. Duh?