Stairwell
Enclosed building section housing the staircase.
The stairwell — in building regulations also called the stair enclosure — is the enclosed building section that houses the staircase and its access points. In apartment buildings, the stairwell as an escape route must meet special fire-protection requirements: fire-retardant or fire-resistant walls, self-closing doors and smoke ventilation. The stairwell is often the design centrepiece of a building.