Ive a broken window pane in a bathroom, i went to the glaziers today and asked for a new pane with a circular hole for a fan but he asked how big a hole I said standard size but he said there is no standard.
I was thinking of putting a cheap plastic vent there at first but maybe later a humidity controlled vent, but i have no experience of these.
Any advice please, what size hole, what to put in there?
George