To build a good staircase it is important to consult local building codes and make careful measurements. Slight errors in step height or evenness can be a hazard, warns Popular Mechanics.
The three main measurements of a staircase are the width, rise and run. The rise is the total height of the staircase, which is a vertical measurement starting at the floor below the staircase to the floor above the staircase. The number of steps is the rise divided by seven rounded down to the nearest whole number. For example, if the rise is 92 inches, the number of steps is rounded down to 13. The height of each step is the rise divided by the number of steps. The resulting step height should be between 7 and 8 inches.
The run of the staircase is the horizontal distance traveled when climbing the stairs, which equals the number of steps multiplied by the horizontal depth of each step. The horizontal depth of a step is the distance from its front edge to its back edge, which should be at least 10 inches. For safety and comfort, a staircase should be at least 4 feet wide, and for tall staircases, an intermediate landing can provide an easier climb, suggests Popular Mechanics.