American Design Drafting Association (ADDA) Certification 2025 – 400 Free Practice Questions to Pass the Exam

The component that provides the vertical height in stairs is the riser. In stair design, the riser is the vertical part of the stair that connects one tread (the horizontal part where you step) to the next. Each riser contributes to the overall height of the staircase, determining how tall each step is.

Risers are important for ensuring safety and comfort in stair design; the height should be consistent to prevent tripping hazards. The total number of risers and their individual heights together define the overall height of the staircase, which is critical in building codes and accessibility standards.

In contrast, the stringer supports the treads and risers but does not contribute directly to the height measurement. Treads are the flat surfaces where you place your feet and contribute to the depth of the stair, while a landing serves as a flat area at the top or bottom of the stairs (or between flights of stairs) and does not provide vertical height.