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Bathroom Fitting Question
Ducting system for bathroom extractor fan
I have a bathroom which abuts onto what was garage (henceforth referred to as 'garage') sharing a wall with the house. The duct for the bathroom extractor fan used to exit the bathroom through the 'garage' below the ceiling, proceeding for about 2ft horizontally until it turned a right angle to proceed vertically upwards through the ceiling, loft and roof of the 'garage' to end in a kind of chimney protruding about 2ft above the 'garage' roof. The duct was round and about the same diameter as a soil pipe. I wanted the extractor fan pipe raised above the ceiling. In order to accomplish this the builder has removed the horizontal part of the duct, leaving only the vertical part. The part attached to the bathroom fan he has replaced with a duct that is rectangular in cross section and is shaped like a step in order for it to go above the ceiling. He has connected the rectangular end (now above the ceiling) to the round end (exiting from the loft through the 'garage' roof) with white tape by constructing a conduit about a 1ft long and which rises diagonally,out of the tape. It seems to me the sides of the duct need to be firm enough not to collapse if there is any vacuum effect and that maybe there should be a condensation trap? He maintains that the tape is very good quality and will prevent the egress of moisture into the loft and that the original ducting system was non standard and therefore difficult to fit. At the moment I am afraid to use the bathroom fan in case I wreck it. And does this particular arrangement of the builder's contravene building regulations?
You can check part L of the building regulations online hope this helps
Answered 18th Jul 2013