How to Calculate Unit Run in Staircase Design

What is the horizontal distance between each step on a staircase called?

a) Tread width b) Unit run c) Riser height d) Total rise

Answer:

a) Tread width

When designing a staircase, it is important to understand the concept of unit run. The horizontal distance between the face of one riser to another on stairs is referred to as the 'Unit run' or 'Tread width'. It corresponds to the depth of each step.

In the context of stairs, the unit run is crucial for determining the layout and dimensions of the staircase. It affects the overall design and safety of the staircase.

For example, with a step width of 0.2 m (or 20 cm) and a step height of 0.15 m (or 15 cm), the unit run or tread width would also be 20 cm. It essentially refers to the 'depth' of the step on a staircase, i.e., the part where you place your foot. The riser height, on the other hand, refers to the vertical distance between each step.

To ensure that your staircase meets building codes and standards, it is important to calculate the unit run accurately. This will help in creating a safe and functional staircase for users.

Remember, the unit run is just one of the many factors to consider when designing a staircase. It is essential to take into account other aspects such as total rise, tread depth, and riser height to create a comfortable and user-friendly staircase.