"My new bathroom bathroom extractor fans fan"

I got the electrician round - finally - to sort the cooker hood which went bang before Christmas: It turns out THAT was only a fuse in a plug that went pop! "BUT I got another job for you". I'd noticed a stain beside the extractor fan and decided this had to be something sinister! Turns out the extractor and the pipe were not connected and the fan was just extracting into the loft. I wonder if that solves another apparent "roofing mystery". The fan was making such a racket "that ain't right". All that is keeping the pipe in place is a piece of wood underneath it.

This was clearly a "build a house kit".