Architecture · Stairs

Stair Width (Clear)

Minimum clear width of a stairway, measured between finished wall surfaces.

914 mm / 36 in min

Description

Clear stair width is measured wall-to-wall (or handrail-to-handrail if handrails project more than 4.5 in). Egress stairs in commercial and multi-family buildings require greater width than typical residential stairs.

Sources

  • IRC
  • IBC
  • Architectural Graphic Standards

Tags

Values

Residential minimumMinimum
914 mm36 in
Commercial egress minimumMinimum
1118 mm44 in
High-occupancy egressRange
1220 mm+48 in+

Related dimensions