I cocked up bathroom fan but have a solution

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so agreed I would run the cables, electrician then checks, I connect up and elec comes back and does all final checks. Lighting circuit is looped at switch and a fused spur feeds bathroom Extractor fan downstairs, which has no window. I forgot to add in a perm live as well as switched. So no overrun on Extractor fan. I eventually found a solution that didn't involve having to rip out plasterboard, or even run any new wires.  Change the switched live to a perm live (easy done where the fan gets its feed from the light switch). Obviously then through a fused fan isolator switch. Then install a vent axia Bluetooth light sensitive fan. Comes on when it detects light hass come on, or if it gets high humidity and just set it vis Bluetooth controller to overrun for 15mins after light goes off.

 

Works a treat.