Entry into a clandestine spaces can vary, including pulling off the homeowner's favorite book from a shelf, touching the right spot on a wall, or even having to play the right series of notes on a piano or moving chess pieces in the right order to get a wall to move.
Humble said requests for incognito doors has increased in the past few years, and that the trend has shifted toward security recently. About 30% of his business is creating designs for high-security rooms, which can involve bullet- and soundproof doors, integrated alarm systems with surveillance and retina or finger scans.
