I need to instal a chimney style cooker extractor fan/hood which I haven't bought or even chosen yet! I am in the process of sorting the electrics out for the new kitchen (building site at mo) and need to know whether most extractor fan hoods run from the normal ring main wiring or whether it should be wired up to the isolated cooker main - if you know what I mean. Someone out there will find this easy - I do know it kinda depends on what type of extrtactor hood you buy, but I just wondered if anyone knows the wiring requirements for a bog-standard glass/chrome chimney extractor hood which can either do filtering the air through filters or through an outside vent? Ta.