TL;DR
Tread depth is the horizontal distance from the nose of one stair tread to the nose of the next, the measurement that determines how much foot landing each step offers. The IRC requires at least 10 inches on residential stairs, measured nosing to nosing, with no more than 3/8 inch variation between the deepest and shallowest step in a flight.
What it means
Tread depth is the horizontal distance from the nose of one stair tread to the nose of the next, the measurement that determines how much foot landing each step offers. The IRC requires at least 10 inches on residential stairs, measured nosing to nosing, with no more than 3/8 inch variation between the deepest and shallowest step in a flight. Deck builders set it together with riser height so twice the riser plus the run lands near the comfortable 24-to-25-inch rule of thumb.
Where it sits in the glossary
Tread depth is part of the Trade jargon group inside the ProFix Directory glossary. Browse every term in this category from the glossary index.
Why Ohio homeowners should know it
This is a term Ohio homeowners encounter when reading contractor quotes, hiring paperwork, or inspection reports. Understanding it well enough to ask one good follow-up question is usually all the protection a homeowner needs.
ProFix Directory keeps definitions short on the index page and saves the longer context — Ohio-specific rules, where the term comes from, and which ProFix tools touch it — for these per-term pages so the term is easy to cite and easy to share.
ProFix tools that touch this term
See also
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