Heated Towel Rail wired from an adjacent room

[ColinB]

I'm wondering whether I can legally wire up a heated towel rail that is in a bathroom myself by siting the spur in an adjacent room.

 

Could I take the flex from the towel rail thro' the wall via a flex outlet plate to an RCD protected fused spur outside the bathroom?

[joe90]

I did this into a cupboard behind the wall in my current house.