Bathroom extractor

[Jupiter01]

I often use soil-pipe, which is about the right size, and handy to have around. It is thicker than ventilation duct, and less easily damaged. The internal diameter seems to be a bit tight, though, and I have had difficulty fitting some brands of fan to it

My pipe that pops out of the roof is a grey soil pipe. Perhaps I should buy another length of that?
I do think that I will need small sections of the flexi pipe to go from the pump to this soil pipe (due to the levels I described above) and then again, where it connects to the grey pipe out of the ceiling. Perhaps the latter can be avoided if I am able to use the grey soil pipe.

 

[Taylortwocities]

You could, of course, use the proper pipe for the job! This is a 2metre length, they do other lengths too.
https://www.tlc-direct.co.uk/Products/FD42000.html

 

[SUNRAY]

You could, of course, use the proper pipe for the job! This is a 2metre length, they do other lengths too.
https://www.tlc-direct.co.uk/Products/FD42000.html

There is a tendancy to use soil pipe as it is heavier gauge [and theoretically the same internal diameter as vent pipe although my experience says it is often slightly smaller], as having more mass it tends to not generate as much noise.