Tread
The part of the stairway that is stepped on. It is constructed to the same specifications (thickness) as any other flooring. The tread "width" is measured from the outer edge of the step to the vertical "riser" between steps.

The part of the stairway that is stepped on. It is constructed to the same specifications (thickness) as any other flooring. The tread "width" is measured from the outer edge of the step to the vertical "riser" between steps.
