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Unsupported Wall?

Discussion in 'Residential Foundation Codes' started by Francis Vineyard, Sep 20, 2011.

  1. Francis Vineyard

    Francis Vineyard Sawhorse

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    In 2009 the concrete tables R404.1.2(2) through (7) now says Maximum Unsupported Wall Height; how is it unsupported?
     
  2. steveray

    steveray Sawhorse

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    Without looking....Aren't they talking about the difference between interior and exterior grade heights?
     
  3. Sifu

    Sifu Gold Member

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    A wall is typically supported at the bottom by a slab and at the top by construction of a floor system.

    The 2006 commentary:

    "Lateral support at the top and bottom of the foundation

    wall must be provided to resist the lateral loads imposed

    on the foundation wall.

    The prescriptive bottom support is provided by a

    basement floor.

    The top support is provided by connections and anchor

    bolts as prescribed in Tables R404.1 (1) and (2)."
     
  4. Francis Vineyard

    Francis Vineyard Sawhorse

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    When to use Tables R404.1.2(2) through R404.1.2(7) or Table R404.1.2(8) is based on where the vertical rebar is placed; section R404.1.2.3.7.2 reads identical to the commentary for section R404.1.2.2;

    “Tables R404.1.2(2) through R404.1.2(7) require the vertical steel to be located at the centerline of the wall. Table R404.1.2(8) requires the steel to be located with a maximum cover of 1¼ inches from the inside face of the wall. Tables R404.1.2(2) through R404.1.2(8) are based on reinforcing bars of Grade 60. Table R404.1.2(9) provides for use of an alternate grade of steel and bar size."

    “Unsupported Wall Height” is simply the distance between the lateral support at the bottom and top of the wall. Table R404.1.2(8) footnote “e” mentions unsupported height whereas the other tables footnote “d” is a given from the table referenced.

    May an expert add; confirm or deny my presumption.
     
  5. steveray

    steveray Sawhorse

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    I was thinking unbalanced backfill.....sorry....I think I wouuld agree with you FV..
     
  6. Daddy-0-

    Daddy-0- Moderator

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    Don't have my book but there is a section for max. unbalanced fill that is used for limiting the amount of fill you can place BEFORE the wall is laterally braced.(floor slab and floor joists.)
     

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