Replacing Bathroom Ducting

[relicalpha]

Hi,

Found my bathroom's extractor fan ducting has a hole which has now started causing a problem in colder temperatures and leaking through the ceiling It looks easy enough to buy some more and replace, however to prevent me screwing it up please could someone suggest how I might remove and refit the ducting from the plastic roof vent end shown below?

I was expecting a metal clip or similar but it seems to go directly into the plastic vent with no obvious removal method - would you expect the end of the plastic pipe to pop off? Or should I just pull/force the ducting downwards? Or could it be glued in or something? Thanks for any help!

 

[Demon]

I've had various ducting kits that have a plastic collar that has a large screw thread on the inside that the flexible ducting actually 'screws' in to it.. Then I've had kits where it's bonded in.. either way, I'd start trying to just twist it gently and see if it can unscrew from the end..

When replacing it, I'd suggest not coiling it up as shown currently, not only does the inner diameter of the tubing reduce when bunched up, but having such a sharp set of bends will impede air flow as well..
When I moved in, the extractor was similarly ducted, I just cut the flexible ducting down to a fraction of it's length, pulled it to extend so it wasn't collapsed and just had a single gentler bend in it and the air flow increase was quite significant..

 

[relicalpha]

I've had various ducting kits that have a plastic collar that has a large screw thread on the inside that the flexible ducting actually 'screws' in to it.. Then I've had kits where it's bonded in.. either way, I'd start trying to just twist it gently and see if it can unscrew from the end..

When replacing it, I'd suggest not coiling it up as shown currently, not only does the inner diameter of the tubing reduce when bunched up, but having such a sharp set of bends will impede air flow as well..
When I moved in, the extractor was similarly ducted, I just cut the flexible ducting down to a fraction of it's length, pulled it to extend so it wasn't collapsed and just had a single gentler bend in it and the air flow increase was quite significant..

Thanks a lot - turns out it's bonded to the bottom 10cm of the roof pipe. I've broken it off at the bottom and removed it.

Do you think I could just saw off the bottom section of pipe where it's glued in, then just clip a new one onto the vent pipe? Is there anything to be careful of doing that?

As a more general point here, with that pipe joining a vertical plastic vent, is condensation sitting in the bottom loop of the tube not always going to be a big issue? As it's a large pipe am I safe to assume it will just evaporate?

 

[Demon]

Thanks a lot - turns out it's bonded to the bottom 10cm of the roof pipe. I've broken it off at the bottom and removed it.

Do you think I could just saw off the bottom section of pipe where it's glued in, then just clip a new one onto the vent pipe? Is there anything to be careful of doing that?

As a more general point here, with that pipe joining a vertical plastic vent, is condensation sitting in the bottom loop of the tube not always going to be a big issue? As it's a large pipe am I safe to assume it will just evaporate?

Regarding rejoining the ducting, absolutely, it's just ducting, nothing special so I'd probably cut it off and attach any which way I could..

Regarding condensation, the fact air is flowing should prevent any real build up, the entire point of ventilating is to stop it condensing, when mine got blocked due to a leak that was dragging in fibres of insulation, there was minimal signs of condensation and my vertical pipe that goes to be ridge tiles is metal!

 

[2004typer]

How big is the hole? Noticed it's an aluminium duct - would it be feasible to get some aluminium duct tape and wrap it around the duct where the hole is?

 

[JRJ]

What's nearby? if worried about condensation you could run it in solid ducting with a condensation trap fitted but would need somewhere for the drain to run.