California IDEX Practice Exam

What is included in the rise of a stair?

1. The distance from finish floor slab to finish floor slab

2. The total number of steps in a staircase

3. The width of the stair tread

4. The height of the stair riser

The correct answer is: The distance from finish floor slab to finish floor slab

The correct answer pertains to the overall vertical measurement in a staircase. The rise of a stair specifically refers to the vertical distance that the stairs cover from one finished floor surface to another, typically measured from the top of one finished floor slab to the top of the next. This definition is crucial for understanding how stairs are constructed and ensures that they meet building codes and safety standards. The height of the stair riser is integral in determining the overall rise since multiple risers contribute to the total vertical height between floors, but it is not the definition of “rise” itself. Other options do not align with the concept of stair rise. The total number of steps provides a count but doesn't inform us of the vertical distance; the width of the stair tread is concerned with the horizontal space where one steps, rather than the vertical rise; and while the height of the riser contributes to stair design, it refers to an individual component rather than the total vertical distance in context.