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Exhaust Vent Pipe leaking and Causing Damp

Postby Beatrice1711 » Sun Nov 20, 2022 1:23 am

I have a damp ceiling near a vent pipe.

I climbed into my loft and can see that the roof is dry but the vent pipe is leaking at the joins where it curves.

Climbing onto the roof, the vent pipe looks like this.

The roofer came and said that I will need a pvc cap fitted over that pipe and minor repairs around the base of the pipe.

Let me know if all this makes sense and if we think that this is all I would require to stop the leak?
Vent pipe (rotate clockwise 90degrees)
Ceiling leak
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Simply Build It

Postby stoneyboy » Mon Nov 21, 2022 9:30 pm

Hi beatrice1711,
The first thing to try is to identify which joints are leaking in the loft and to remake them.
If they are solvent joints use pvc glue, if they are ring seal use silicone mastic.
The apron around the pipe at roof level may be leaking but if this is happening you may be able to see daylight when you look inside to confirm this.
I have never seen a cap fitted on a soil vent pipe - don't waste your money.
Regards S
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Postby somuchdiy1 » Sun Jan 22, 2023 5:22 pm

hi should a wall extractor fan in kitchen have a pipe in it. mine doesnt it just sits in the wall cavity , it does have a vent cover on external wall but no ducting inside. thanks
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Postby stoneyboy » Sun Jan 22, 2023 10:55 pm

Hi somuchdiy1,
Yes there should be either solid pipe or flexible ducting connecting the two otherwise damp may form in the cavity. A short piece of flexible hose is the easiest to fit.
Regards S
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