What Is the Headroom Calculator?
Verify minimum headroom clearance for stairways with our free headroom calculator. Insufficient headroom is a common code violation that can require expensive redesigns. This tool checks clearance at every point along the stair run and identifies the critical measurement point.
How to Use This Calculator
- Enter the total rise, tread depth, and floor thickness above the stairs.
- Set the required minimum headroom (80 inches per IRC).
- Review the headroom measurement at the critical point - where the stair first passes under the upper floor.
Why Accurate Headroom Calculations Matter
The IRC requires a minimum headroom of 6 feet 8 inches (80 inches) measured vertically from the tread nosing to the ceiling or any obstruction above. Headroom violations often aren't discovered until framing is complete, making them extremely costly to fix.
Building Code References
Related Tools
Frequently Asked Questions
What is the minimum headroom for stairs?+
The IRC requires 6 feet 8 inches (80 inches or 2,032 mm) of headroom measured vertically from the tread nosing to any obstruction above, along the entire length of the stairway.