The "Total Run" of a stairway is _____.

The "Total Run" of a stairway refers to the horizontal distance covered by the stairs, which is calculated by measuring the sum of the tread runs. Each tread run is the part of the stair where a foot lands, and when these individual tread runs are added together, they provide the total horizontal length of the stairway from the starting point to where it finishes. Understanding the concept of total run is essential for ensuring that stairways comply with building codes and provide safe, accessible use.

The other options focus on different aspects of stair construction. The total height of the stairs relates to the vertical measurement, which is not what total run addresses. The vertical rise pertains specifically to the elevation change, while the width of the staircase indicates how broad the stairs are at any point, neither of which captures the idea of total run accurately.