gray area id say if yur connecting it up to the bathroom light fitting it is
hmmm, if the bathroom has downlights, then the connections are outside the bathroom. as you say, a bit of a grey area.
gray area id say if yur connecting it up to the bathroom light fitting it is
It's a passive vent. Quite common. Regards, Davidas far as i can see there is no fan visible outside on the duct. which makes me wonder if it was a forgotten job as a duct is in place.