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

The term "total run" refers specifically to the horizontal span or length of a stairway, which is the distance measured along the ground from the start of the staircase to the end. This measurement is essential in stair design and construction because it impacts not only the overall footprint of the staircase but also compliance with building codes that dictate proper dimensions for safety and accessibility.

Understanding the total run is crucial for ensuring that the stairway is comfortable to use and meets specific design standards. The total rise, on the other hand, refers to the vertical distance between the two levels that the stairs connect, while terms like stairway length or stair span are less commonly used and may not accurately convey the intended measurement, making them less appropriate in this context. Thus, total run is the most precise and commonly accepted term for describing the horizontal length of a stairway.