מחשבון מדרגות

The ideal riser height is 7 to 7.5 inches. The ideal tread depth (run) is 10 to 11 inches. The sum of one rise plus one run should be between 17 and 18 inches for comfortable stairs.

Divide your total rise (floor to floor height in inches) by 7.5. A standard 9-foot ceiling typically needs 13-14 steps. A standard 8-foot ceiling needs 12-13 steps.

Building codes require a minimum of 80 inches (6' 8") of headroom measured vertically from the nosing of each tread to any overhead obstruction.