1. Visiting from the US? Why not try DIYnot.US instead? Click here to continue to DIYnot.US.
    Dismiss Notice

Extractor duct at an angle

Discussion in 'Plumbing and Central Heating' started by Jupiter01, 13 Oct 2019.

  1. Jupiter01

    Jupiter01

    Joined:
    30 Mar 2015
    Messages:
    2,602
    Thanks Received:
    28
    Country:
    United Kingdom
    I am kicking myself as I’ve made the same mistake as I did a few months ago!
    I’ve drilled out the extractor hole and fitted a vent on the outside. Now that I’ve tiled the bathroom, I’ve noticed that the duct is not level and hence the extractor is raised by an inch at the top.

    I could use a flexible duct but that will need me to clim on a ladder outside to fix it to the vent.

    can I instead, use half rigid pipe and half flexible? This will mean that I can push the rigid pipe against the vent from the inside and then use the flexible duct to connect to the extractor unit.

    Thanks in advance.
     
  2. Sponsored Links
  3. SFK

    SFK

    Joined:
    23 Jul 2010
    Messages:
    1,553
    Thanks Received:
    358
    Location:
    Oxfordshire
    Country:
    United Kingdom
    • Thanks Thanks x 1
  4. Jupiter01

    Jupiter01

    Joined:
    30 Mar 2015
    Messages:
    2,602
    Thanks Received:
    28
    Country:
    United Kingdom
  5. SFK

    SFK

    Joined:
    23 Jul 2010
    Messages:
    1,553
    Thanks Received:
    358
    Location:
    Oxfordshire
    Country:
    United Kingdom
    Yes. That is the correct flex pipe.
    Note that there is also a kit here (that I have not used) that shows that this is normal practice: https://www.screwfix.com/p/manrose-tumble-dryer-termination-kit-100mm/11703?_requestid=653921
    I attach the flex pipe to the coupler with a zip cable and couple of self taping screws. Then I normally simply push the connector into the straight pipe as a non-permanent join so I can clean later if needed. A bit of glue if you wish to make it permanent.

    But you have a potential problem depending on direction of tiit.

    I always tilt the pipe in the outside wall downward towards the outside.

    The outside wall tends to be cold. The water vapour being moved by the fan can condense on the cold walls of the pipe in the wall, forming water droplets.

    If the wall pipe is tilting down towards the outside the drips of condensed water flow outside with no issues (it will only be a few drops on outside wall).

    But if the wall pipe is tilting down towards the inside, the drips water from the condensation can collect in a U section of the pipe and then leak onto the ceiling. This is not always an issue (if only a bit condenses) but can leave a stain or damage on ceiling if there is a lot of condensed water (ie cold day with lots of steamy showers).

    SFK
     
    • Thanks Thanks x 1
    • Like Like x 1
  6. Sponsored Links
  7. SFK

    SFK

    Joined:
    23 Jul 2010
    Messages:
    1,553
    Thanks Received:
    358
    Location:
    Oxfordshire
    Country:
    United Kingdom
  8. Jupiter01

    Jupiter01

    Joined:
    30 Mar 2015
    Messages:
    2,602
    Thanks Received:
    28
    Country:
    United Kingdom
    My pipe slopes down in an inward direction. I assume the u section will be inside the cavity and any drips will be here? I assume that's not too unusual for the cavity?
     
  9. SFK

    SFK

    Joined:
    23 Jul 2010
    Messages:
    1,553
    Thanks Received:
    358
    Location:
    Oxfordshire
    Country:
    United Kingdom
    If you are using straight pipe in the wall, by which I mean this:
    https://www.screwfix.com/p/manrose-100mm-round-ducting-1m/544gy
    any water will flow back to the joint between the straight pipe and the flexible pipe. For me this is normally at the inside wall (as I put the straight pipe all the way though the wall so that it is flat on the inside wall and on the outside wall).

    Note that what I have suggested might be a problem, is only a small risk as the air is normally moving fast and this condensatation issue happens more often where the pipe goes through a cold roof. So I would not get worried about it, but I wanted to warn you of the risk as it is a possibility.

    SFK
     
    Last edited: 14 Oct 2019
  10. Jupiter01

    Jupiter01

    Joined:
    30 Mar 2015
    Messages:
    2,602
    Thanks Received:
    28
    Country:
    United Kingdom
    update: this worked a treat @SFK. My extractor is now flush against the tiles.

    Just noticed I don’t have the finished pic. Here’s work in progress.

    Thanks for your help
     

    Attached Files:

  11. DIYnot Local

    DIYnot Local

    Joined:
    3 Sep 2019
    Country:
    United Kingdom

    If you need to find a tradesperson to get your job done, please try our local search below, or if you are doing it yourself you can find suppliers local to you.

    Select the supplier or trade you require, enter your location to begin your search.


    Are you a trade or supplier? You can create your listing free at DIYnot Local

     
Loading...

Share This Page