Tread — Underfoot element
Category: Underfoot element
Horizontal, walkable part of a stair step.
The tread is the horizontal, walkable part of a stair step. It carries the entire foot load and, together with the riser, forms the complete step element. In open stairs, the riser is absent; in closed stairs, the tread is connected to the riser. The surface of the tread must be slip-resistant and abrasion-proof.
Related terms
Related terms: Tread Depth (Going), Riser, Projection Depth, Knot Grade, Stringers, Tread Thickness.