Three-Quarter Turn Stairs change their directions through 270° by the time the stair reaches the next floor. The direction is changed three times through three right angles, with the upper flight crossing the bottom one. In this type of construction, an open well is formed. This type of stair is normally used when a space has a greater vertical distance but a limited length. Some flights have very few risers, and the landings can provide a place to stop and rest during ascension.
For stairs serving a single user (typically private residential), a minimum of 36” (91 cm) is required. In general public spaces a minimum of 44” (112 cm) must be met—providing ample space for one person and allowing the tight passage of two people. Comfortable two person stair widths range between 49” (125 cm) to 60” (152 cm). For three simultaneous users, a minimum of 74” (188 cm) is recommended. Handrails must be placed every 60” (152 cm).
Three-Quarter Turn Stairs change their directions through 270° by the time the stair reaches the next floor. The direction is changed three times through three right angles, with the upper flight crossing the bottom one. In this type of construction, an open well is formed. This type of stair is normally used when a space has a greater vertical distance but a limited length. Some flights have very few risers, and the landings can provide a place to stop and rest during ascension.
For stairs serving a single user (typically private residential), a minimum of 36” (91 cm) is required. In general public spaces a minimum of 44” (112 cm) must be met—providing ample space for one person and allowing the tight passage of two people. Comfortable two person stair widths range between 49” (125 cm) to 60” (152 cm). For three simultaneous users, a minimum of 74” (188 cm) is recommended. Handrails must be placed every 60” (152 cm).
