How many stringers for stairs?

Discussion in 'Decks & Patios' started by diynewf, Aug 19, 2016.

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  1. Aug 19, 2016 #1

    diynewf

    diynewf

    diynewf

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    I'm in the process of repairing steps leading into my basement apartment. The threads are put together with 2x10 pressure treated lumber and the riser height is 6 3/16" high. There's 2 stringers spaced 36 1/4" apart. Do I need to add a 3rd stringer in the middle or will 2 suffice? I'm not sure what the max span distance for 2x10 board, but the old steps seemed to have held up pretty good over the years, no signs of warping etc.
     
  2. Aug 19, 2016 #2

    nealtw

    nealtw

    nealtw

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    2 will work but the third one takes the bounce out of them. If the first two are attached to wall, install the middle tread first, it helps line up everything.
    I would change the treads to 2 2x6s, 11 inches is a lot more comfortable to walk on
     
  3. Aug 20, 2016 #3

    GBR

    GBR

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    If they are "cut" stringers (notched for treads/risers), 3 are required per code, which you would want inspected as for your liability when you change places with your renters upstairs. If in US, under Prescriptive Codes, 10" is required for minimum tread depth and no nosing IF open risers ("closed" stringer construction). Also note you MAY be required to follow the maximum 6' stringer span for a cut stringer without mid-support. All found here; http://www.awc.org/pdf/codes-standards/publications/dca/AWC-DCA62012-DeckGuide-1405.pdf

    Gary
     
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  4. Aug 29, 2016 #4

    Mastercarpenty

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    Ditto GBR. Even when doing work that won't be inspected or is grandfathered in, I use or add a center stringer when tread width exceeds 24". Given the risks should they fail, I overbuild my stairs- just good common sense to do that.

    Phil
     

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