Originally Posted by sparkyork

hi matey, welcome to the forum.

firstly are you in rented accomodation or is it your own property? if its rented then get your landlord to sort it out!

if its your own property then as your going to be carrying out work on this circuit then it should be rcd protected. i could be wrong as well but im led to beleive that there should be a suitable pull switch or the like, within the bathroom aswell (someone will confirm whether im wrong or right on this!)

imo, if someone comes to quote for the work then:
1, they will check your main earth bonding to your gas and water or oil services

2, they will possibly either a)upgrade the isolator switch to a rcd protected outlet or b)recommend upgrading your fuse board and feeding the shower from this

3, if they discover that the cable supplying the shower is 6mm they may upgrade this 10mm (i would personally), they may also say that you should have access to electrical switch for the shower within the bathroom

id be expecting to pay at least £150 for the works, and possibly alot more if your main earths need wiring as well as possibly a new fuse board.

hope this helps in anyway.

rich