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40mm condensate pipe

Discussion in 'Plumbing and Central Heating' started by Fallout, 18 Mar 2021.

  1. Fallout

    Fallout

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    If running 40mm pipe for a boiler condensate from internal to external with lagging. Is it advisable to lag through the wall cavity? Or will it effect the cement seal.
     
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  3. Madrab

    Madrab

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    I wouldn't, unless the hole's a bit on the larger side .... ;)
     
  4. muggles

    muggles

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    Yes, HHIC guidance is to insulate through the wall, with a minimum internal pipe diameter of 30mm.

    Screenshot_20210318-224231_Drive.jpg
     
  5. ScottishGasMan

    ScottishGasMan

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    Yes the preference is to lag through the wall. But very rarely ever see it done. If you didn't then you'd need to make sure the lagging is sealed to the wall with the likes of silicone
     
  6. Madrab

    Madrab

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    Never seen it referenced for a 40mm (46mm) waste pipe, for a 32mm pipe yes but not a 40mm.
     
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  8. ScottishGasMan

    ScottishGasMan

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    The referance is always "a minimum of 32mm AND insulated" So the gas safe inspectors tend to take that as 32mm or bigger and insulated, as opposed to insulated 32mm, but not on larger pipes.
     
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  9. Madrab

    Madrab

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  10. Fallout

    Fallout

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    Cement would eat in to the lagging/not seal due to movement in the lagging?
     
  11. Fallout

    Fallout

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    Or can cement be used?
     
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