What StairSolver checks
Inputs used for this warning
- lowest ceiling height above the stair
- opening length
- selected stair layout
User input fields: lowest ceiling height above stair, ceiling or floor opening length.
Headroom
Headroom is the tightest overhead clearance along the stair path, and it often becomes the hidden problem in basements, attics, and remodels.
The short answer
StairSolver uses this as a baseline planning check. If the measurement crosses the threshold, the report explains what number triggered the flag and what to ask before building, buying, or approving a plan.
Report boundary
Baseline risk, not local approval.The local authority, inspector, engineer, or qualified stair professional still decides the final answer for the exact property.Referenced article content
This is a StairSolver summary of the cited source content, written in plain language so you can understand the rule before opening the official reference.
What StairSolver checks
User input fields: lowest ceiling height above stair, ceiling or floor opening length.
Why it matters
What to ask before building
What this page cannot prove
Official source links
These links leave StairSolver. Use them when you want to verify the official citation, then come back to the calculator to test your dimensions.
Baseline residential stair check for minimum stairway headroom.
International Code Council / irc-baseline-2026-07-01Open 2021 IRC R311.7.2