This Architectural Drawing is of Detail section of stairs. The riser is the vertical surface of the stair. The tread on the other hand is the horizontal surface of the stair and the part of the stair you step on. Nosing is the portion of the tread that overhangs the front of the riser. Often a stair builder will talk about the rise and run of the stair. There are three main components to design when building a staircase – the treads, risers, and stringers. Stairs must be at least 36" wide with a minimum headroom of 6' 8" Risers must have a maximum height of 7 ¾" and open risers must be 4" high or shorter. Each tread in a stair must have a minimum depth of 10". The treads of curved staircases must not be less than 6" deep. For more details and information download the drawing file.
