Young Brunette Girl Outside On The Old Rock Stairs

• The slope or pitch of the stairs is the total rise divided by the total run (not the individual riser and treads due to the nosing). It is sometimes called the rake of the stairs. The pitch line is the imaginary line along the tip of the nosing of the treads. In the UK, stair pitch is measured in degrees from the horizontal.
• Headroom is the height above the nosing of a tread to the ceiling above it.
• Walkline – for curved stairs, the inner radius of the curve may result in very narrow treads. The "walkline" is the imaginary line some distance away from the inner edge on which people are expected to walk. Building code will specify the distance. Building codes will then specify the minimum tread size at the walkline.
• To avoid confusion, the number of steps in a set of stairs is always the number of risers, not the number of treads.