Redecoration is the work of changing how a room looks — new paint, new wallpaper, new curtains, sometimes new furniture. The word is a noun: it names the job, not the doing of it. People say “the redecoration of the kitchen” or “after the redecoration.” It does not mean building a new room from nothing; it means dressing an old room in a new look. Though actually, in everyday speech a lot of people just say “we’re redecorating” (the verb) and never reach for this noun; “redecoration” turns up more in writing, on bills, and in slightly careful talk.