secret room IN the stairs! I need a secret room somewhere in my house. So have the secret room under the stairs, but to actually make it secret, don't put the door under the stairs, put it in the stairs.
A secret storage in a staircase can be a great hidden storage for bulky things that look unflattering when stored in full display. It’s the same space under stairs only hidden and accessed from the floor in the staircase. At: The Bottom Of The Stairs