TL;DR
A stair stringer is the diagonal structural member, sawn from 2x12 lumber or formed in steel, that carries the treads and risers of a staircase from one level to the next. Cut stringers are notched to receive treads, which leaves as little as 5 inches of effective depth at the throat, so spans are short and deck stairs commonly need stringers every 12 to 18 inches under composite treads.
What it means
A stair stringer is the diagonal structural member, sawn from 2x12 lumber or formed in steel, that carries the treads and risers of a staircase from one level to the next. Cut stringers are notched to receive treads, which leaves as little as 5 inches of effective depth at the throat, so spans are short and deck stairs commonly need stringers every 12 to 18 inches under composite treads. The IRC's geometry rules, maximum 7-3/4-inch rise and minimum 10-inch run, are laid out on the stringer before the first cut.
Where it sits in the glossary
Stair stringer 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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