What is the horizontal span or length of a stairway called?

What is the horizontal span or length of a stairway called?

• A. Span
• B. Tread
• C. Total rise
• D. Total run

Answer: (D)

In stair measurements, you separate vertical rise from horizontal run. The horizontal span the stairway covers is called the total run—the overall distance along the floor projection from the start of the stairs to the end. Each step has a tread, which is the individual horizontal surface you step on, but the run is the sum of those treads laid out across the whole staircase. The vertical distance from bottom to top is the total rise, not the horizontal length. So the correct term for the horizontal length is total run.

In stair measurements, you separate vertical rise from horizontal run. The horizontal span the stairway covers is called the total run—the overall distance along the floor projection from the start of the stairs to the end. Each step has a tread, which is the individual horizontal surface you step on, but the run is the sum of those treads laid out across the whole staircase. The vertical distance from bottom to top is the total rise, not the horizontal length. So the correct term for the horizontal length is total run.