PoP wrote in message . ..

The fan should be a spur from the upstairs ring main, not the lighting
circuit. And upstairs ring mains tend to come up from the floor rather
than down from the loft. Note the word "tend", you can't count on it.

Why not from the lighting circuit? Isn't that the way to wire them if
you want them to switch on automatically with the light switch (eg as
in the case of an internal bathroom/toilet)?

David