As some of you know, I’m writing a book on stairbuilding. One thing that gave me the heebie-jeebies was stringer spans. I think most of us build stairs with only an intuitive grasp of the spans, and a vague discomfort that what starts out as a 2×12 really only acts like a 2×6. In fact, not even that as notching one side of any beam (which a stringer is) destroys its grade.
I found a reference for 2 x12s in the Virginia code. If you leave a minimum of 5 in. below the notch, 2 2x12s can span 8 ft., and three can span 11-3. Even better is LSL material, as referenced below here: http://www.trusjoist.com/PDFFiles/2124.pdf
Thought you’d like to know.
Andy
“Never try to teach a pig to sing. It wastes your time and annoys the pig.” Robert A. Heinlein
“Get off your dead
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Is that meant to read 2 or 3 doubled or tripled up? Or is that just the amount of stringers in said stair?
I read it as the number of stringers per stair.Andy
"Never try to teach a pig to sing. It wastes your time and annoys the pig." Robert A. Heinlein
"Get off your dead #### and on your dying feet." Mom
Andy:
What about using LVL for stringer stock - would that be stronger than LSL?
RJC
I don't know. I do know that Trusjoist publishes LSL span tables that I can hang my hat on in a lawsuit, however.Andy
"Never try to teach a pig to sing. It wastes your time and annoys the pig." Robert A. Heinlein
"Get off your dead #### and on your dying feet." Mom