Run Length — Glossary entry
Category: Glossary entry
Horizontal length of a stair flight in plan.
The run length is the horizontal projection of a stair flight in plan – measured from the leading edge of the bottom step to the leading edge of the top step of that flight. It corresponds to the product of the number of goings and the going itself. The run length is one of the most important planning variables: it determines how much floor area the staircase occupies, and it is the basis for deciding on intermediate landings, curved sections or changes of direction when space is tight. The sum of all flights and landings gives the overall staircase length.
Related terms
Related terms: Stair Flight, Walking Line, Tread Width — Historical Term, Intermediate Landing, Stair Elevation (Workshop Drawing).