Extractor fan Ducting

[ScubaCollie]

Hi All, noticed wet mark on bathroom ceiling and thought roof was leaking.

Went up to the loft and its the cooker extractor fan ducting thats come away from the roof vent and loads of water trapped in it and escaping from the ducting which is of the standard cheap white stuff. It had just been taped to the roof vent.....

My plan is to replace it with insulated ducting however here is my problem.

The ducting comes off a type of soil pipe that's measures 110mm dia? (please see below photo)

However the roof vent pipe is distorted in size and measures 150 in one direction (9 to 3 o'clock) and 170 in the other (6 to 12 o'clock).

Insulated ducting appears to be available in 100, 102, and 127mm dia.

I could jubilee clip the 127mm over the 110mm soil pipe?

However what the hell do I do at the roof vent as above its 150 or 170 dia due to distortion but either way the 127mm isn't going to fit over it.

It was previously shoved up inside and duct taped hence the reason why it fell out...

Also there's no ducting at all on the bathroom ceiling fan and I was going to use a Y Piece to vent both the cooker and bathroom fan through the same roof vent? But they are 110mm dia on all ends of the Y Piece.....

Are there any experts on here

 

[mattylad]

Do you want cooking smells in the bathroom?

You will do if you join them both.

 

[ScubaCollie]

OK I will ommit the Y Piece and just use for the cooker.

How can I connect the ducting to that Roof Vent Pipe?

 

[Taylortwocities]

One of these?

https://www.amazon.co.uk/dp/B08GG2WK5W/ref=cm_sw_r_em_api_glt_fabc_Y2HH2Y25D8RYS5S8X8TW