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  1. guitarman001

    guitarman001 New Member


    I recently bought a new build for my terminally ill wife. I think the place is great but I'm worried about two things I hoped somebody could help me with.

    One is actually the roof - it has soffit vents only - somebody else told me ridge vents would also be good not only for ventilation but to secure the first row of tiles. I don't know what standards dictate.. maybe soffits are enough. (His was a Marley roof and two front tiles fell off before the builder put in ridge vents. Mine is a Russell roof).

    To the main issue.. I remember a co-worker told me years ago that pipes in his loft were connected with tape and that this started to leak waste gases into his loft. He had a battle with his builder to get a proprietary seal put in to join the pipes.

    I understand even if pipes are low pressure, an air tightness test still has to be done, even if just 100mBar for 5 minutes on bathroom exhaust pipe. I don't think that's been done and was told that tape connecting my pipes is ok - duct tape, fit for purpose.

    I'll post two pics and please, if you could advise, that would be a massive help... With the wife's illness I'm really struggling to check this out according to any sort of standard and don't know what to do.

    The one with blue tape is from the kitchen and en suite, I think. The one that looks like it's been sealed with masking tape is the main stack from the main bathroom, I think.. I don't know why tape would be used if a proper rubber seal was already in place..

    Apart from this, and it may not be an issue, I'm pleased and think the site team is good, so want to stay on-side.

    Thank you ! :)


  2. guitarman001

    guitarman001 New Member

    Fyi I'm typing up the snagging list for Monday. If this isn't right and needs sorted, any and all advice is GREATLY appreciated.
    Thanks once again on behalf of both of us!
  3. ShaunCorbs

    ShaunCorbs S. Mod Trusted Plumber GSR Top Contributor!!

    looks like there from an fan/extractor set, and they look fine
  4. jtsplumbing

    jtsplumbing Plumber GSR

    These look more like extractor vents from bathroom/kitchen not main soil vents, some roof spaces require ridge vents for air circulation to stop condension ask your builder about them
  5. guitarman001

    guitarman001 New Member

    Thanks, guys!
    So pipes for an extractor set don't need any sort of rubber seal between them - tape is good enough?

    Though I think I should still ask if they've been pressure tested because my friend did have a break I the tape of his join and it did make his loft a bit smelly!

    Much appreciated!
  6. ShaunCorbs

    ShaunCorbs S. Mod Trusted Plumber GSR Top Contributor!!

    Yes they don't need to be tested as there's no pressure really just a flow of air

    Normally use silver foil tap but gaffa tape works ok as well (the black stuff)
  7. guitarman001

    guitarman001 New Member

    Thanks everybody for your help!
  8. guitarman001

    guitarman001 New Member

    Hi guys,

    Another point that's been raised...

    Should these pipes be insulated? Else if hot air is rising inside and the cold loft air meets the hot pipe, there will be condensation forming and running down the exterior of the pipe?
  9. ShaunCorbs

    ShaunCorbs S. Mod Trusted Plumber GSR Top Contributor!!

    Tricky point non arnt but depends on how long the run is

    And you can get insulted duct flex if they say you can't

    Think with this point I think your fighting a loosing battle
  10. guitarman001

    guitarman001 New Member

    I think so, too.. good to get your take on it though, thank you.
  11. JCplumb

    JCplumb Plumber

    Condensation doesn't form on a hot surface.
  12. guitarman001

    guitarman001 New Member

    Good point.. it's warm air on a cold surface, isn't it? So if it does form, it will be inside the pipe and would drip back down to the extractor itself.
  13. Chuck

    Chuck Active Member

    Drains aren't really my thing, but If the first picture is of the top of a soil stack then I don't like the look of how it's been done much. I think I'd ask some questions about what's under all that tape and wrapping. Where's the rodding point for when a blockage needs to be dealt with?

    I'd prefer it to be either straight up and though the roof via a proper kit or an air admittance valve in the roof space. But, as I said, drains aren't really my thing.
  14. ShaunCorbs

    ShaunCorbs S. Mod Trusted Plumber GSR Top Contributor!!

    It's for a fan
  15. Chuck

    Chuck Active Member

    Hmm, okay. It just seemed odd to me that, if that's the case, it's done so differently from the other one. That and the OP writing "The one that looks like it's been sealed with masking tape is the main stack from the main bathroom, I think.." made me wonder.
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