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Cantilever support of RSJ

Discussion in 'Building' started by Dave337, 14 Aug 2019 at 10:51 PM.

  1. Dave337

    Dave337

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    Hi,

    Just after a spot of advice. We are having an kitchen extension done (knocking out an external wall (c. 5m)) and have an RSJ across gap. Will be resting on single 100mm brick and supported in the centre by an existing perpendicular cantilever RSJ supported by a pillar. My question is - in the plan the pillar is too close to the future external kitchen wall. Structural Engineer calcs I'm sure are all valid etc. I'm just after theoretical ways that the pillar could be moved further back (ie away from new RSJ). Would having thicker columns for the new RSJ to rest on reduce load in the centre and allow the move? Or would thicker steel in RSJ or pillar allow a move?

    I will be speaking with architect and SE tomorrow - just curious on general rules / logic.

    Thanks

    Dave
     
  2. blup

    blup

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    Rather than move the pillar you could ask if it is feasible to do away with it altogether and spec a larger beam in the new opening with the 4 inch brick upgraded if necessary?

    Blup
     
  3. tony1851

    tony1851

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    Are you saying that the 5m beam is being partly supported off a cantilvered beam, which is in turn supported by a steel column?
    Hard to grasp your layout - can you post a plan?
     
  4. ^woody^

    ^woody^

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    Yeah, a plan and a couple of nurofen.
     
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  5. Leofric

    Leofric

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    Yes , one for your architect and SE I think.
     
  6. bernardgreen

    bernardgreen

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    A cantilevered beam is like a see-saw, any weight on the un-supported end has to be matched by weight or tie down at the other end.

    Not all builders know this .
     
  7. ^woody^

    ^woody^

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    We leant this age 5 on the seesaw in the playground.
     
  8. bernardgreen

    bernardgreen

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    We did, but not all builders had access to a playground :mrgreen:
     
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