RSJs on Padstones

Discussion in 'Builders' Talk' started by CRLondon, Jul 19, 2016.

  1. CRLondon

    CRLondon New Member

    I have just had a builder install some padstones and RSJs for some new openings in a cavity wall. I am concerned about the installation for a few reasons.

    1. He has installed the padstones (220 x 200 x 100) sideways so that they span the cavity. I guess this is good for load spreading, but I am concerned as I am unsure whether they are supposed to be used side on, they are bridging the cavity and their now 'top' don't seem to be a smooth as their side faces. This means that the RSJ is in point contact with the high points of the padstone (not evenly spread load).

    2. The padstones are off level. I'm sure this can't be right. I guess it could be dry packed between the padstone and lintel, but seems like a bodge.

    3. The mortar under the padstones has been packed with broken brick.

    I'm not sure if this is a problem, but would really appreciate some expert advice as he is sending through an invoice this evening.
  2. Phil the Paver

    Phil the Paver Screwfix Select

    Photo's we need photo's, to see if its as bad as it sounds.
  3. metrokitchens

    metrokitchens Screwfix Select

  4. KIAB

    KIAB Super Member

  5. chippie244

    chippie244 Super Member

    That was Metro's photo not the OP's
  6. KIAB

    KIAB Super Member

    I have usually fitted padstone edge on ,width of
    I know that, but still carp installtion.:)
  7. KIAB

    KIAB Super Member

    You don't usually lay a padstone flat to bridge a cavity wall, padstone sits on edge on one course of brickwork, you then build the second row with brick or block work.
  8. Jord86

    Jord86 Screwfix Select

    Hi mate, if that photo is representing what your builder has installed then it's very poor to say the least. Do you have any other pictures showing the whole scenario please? Can't understand why the padstones are so low if the guy is a builder who does this type of work day in and out. You can pack the rsj off the pads with slate to level it if needed as it is a durable material, but certainly nowhere near the depth needed for what the photo shows. The padstones should be placed on top of and in line with the supporting walls, not bridging the cavity, with the rsj bearing fully on the area of the padstone. At best would like to think it was only a temporary installation, but as he has cemented it in I would seriously question him if he was planning to leave it like that.
  9. KIAB

    KIAB Super Member

    OP hasn't posted any photo's yet.

    When I've installed rsj's ,have had to use steel shims instead of slate to keep BC happy.:(
  10. metrokitchens

    metrokitchens Screwfix Select

    Well, it is an engineering brick it is resting on. Or maybe a foot from a garden plant pot.
  11. Jitender

    Jitender Screwfix Select

    I'm just looking at my details.

    SE has recommended leaving any props in for at least 7 days.

    On the external wall, how is the outer skin being supported?

    If the steels work hasn't been plastered over, would get BC to come over and check, they told me that they wanted to see any structural work before plastering over.
    KIAB likes this.
  12. KIAB

    KIAB Super Member

    Even using a strong mix, you need a week before removing props, well you did in the old days.:rolleyes:

    Last year, I seen padstones installed, & brickwork below padstone was commons, & not a engineering brick in sight, years ago you always built up with engineering bricks, how times have changed.:(
    I bet builder probably didn't even involve BC.:(
  13. Jord86

    Jord86 Screwfix Select

    Ah I see, jumped the gun a bit there sorry! Not that I don't agree with a bit of overkill here and there for peace of mind but does pertube me how one building control officer will require very different methods and measures used compared to the next(not just meaning rsj's now mind), particularly if it's in the same postcode area. No point arguing with them though......
  14. Jitender

    Jitender Screwfix Select

    This is taken from my calcs:

    Install steel beams and shim / dry pack beams as necessary onto
    padstones to ensure full load transfer.

    d) To minimize cracking of the walls above, preload the new beams by
    using machined steel folding wedges rammed home.
    If the beam is not preloaded there is a risk of initial cracking to the walls
    above as the load is transferred but this will not be progressive.

    e) After preloading the beams dry pack the gap between existing wall and
    the beam using a minimum thickness of 30mm of sand and cement 3:1
    mixed to just bind and then rammed home to ensure a fully packed joint
    for the full width of the beam/wall.

    f) Leave props in place for at least 7 days until the packing is cured.
    KIAB likes this.
  15. KIAB

    KIAB Super Member

    Old school building.:)
    Davmac likes this.
  16. CRLondon

    CRLondon New Member

    sorry, trying to upload photos, but failing due to file size restrictions. First time I have used this site.
  17. CRLondon

    CRLondon New Member

    Here are the pictures of the uneven padstone surface

    Attached Files:

  18. CRLondon

    CRLondon New Member

    and the broken brick packing...

  19. KIAB

    KIAB Super Member

    Total carp,very poor standard of work,completely unacceptable, get BC in to inspect.
    Lintel isn't sitting properly on padstone.

    I'm not there, but looking at photos, I think I would have taken the lot down & built a proper solid pier.
    Last edited: Jul 20, 2016
  20. Davmac

    Davmac Active Member

    Sorry CRL but from those pics, that's a poor job. KIAB is right get the BC in then you have extra weight to throw at your "cough" " builder" to get a proper job done, or at the very least rectified. Strongest point in all the pics is the Acro prop. which in fairness, looks like it's in the centre of the beam.

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