Stair riser

When designing a staircase, the height of the step (riser) is usually 15 centimeters, and the width of the step (tread or step run) is approximately 30 centimeters, so that the foot can sit completely on the step along the entire bottom surface. Such a design reduces the possibility of the foot colliding with the step when climbing, and sliding when falling. However, due to lack of horizontal distance or other reasons, different dimensions may be applied.