Which term refers to the horizontal distance of a stair tread from the nose to the riser?

The term that refers to the horizontal distance of a stair tread from the nose to the riser is known as the "run" of the stairs. In stair design, the run measurements play a crucial role in defining the comfort and safety of the stairs.

The run is an essential aspect of the stairway as it determines how much space is available for a person to place their foot on the tread when ascending or descending. A proper run ensures that the stairs are not too steep and provide a comfortable walking experience.

Understanding this term is also vital for adhering to building codes and safety regulations, which often specify minimum and maximum dimensions for the run of stair treads to ensure user safety.

The other terms listed don't specifically relate to the horizontal distance of a tread. "Depth" may refer to the measurement from front to back of a tread but does not specifically emphasize the relationship between the nose and riser. "Flight" describes a series of stairs between two landings and does not address individual tread measurements. "Landing" refers to a flat area at the top or bottom of a staircase, again not focused on horizontal distance related to the tread itself.