Wiring mirror demister in bathroom

Hi all,

I am refitting my bathroom from scratch and will be putting a 1m square mirror on the wall over the bath central to a tiled wall. This will be attached to 6mm WBP using mirror adhesive then onto the wall. I have seen these self-adhesive demisting pads and want to fit one to enable shaving whilst showering in that area.
Onto the question - having removed an electric shower from that wall I have the wiring that went to it. Can I use this wiring to run the demister? I also want to connect the extractor fan to this circuit as well so they run at the same time. I will probably install another demister to the mirror (1.5m x 1.5m approx) on the wall over the basin/wc worktop. I could then use the isolating pull switch (previously isolated the shower) to switch all of this on and off.
I am thinking the wiring is obviously overkill to run all this and will need to change the size (Amp) of the plug in trip fuse at the consumer unit?
Have I got this in my head okay or am I going about this the wrong way?

Thanks,
Glen

possible

a couple of things
1. part P
2. Bonding requirements- see for reference

So basically I have two choices - get an electrician to do it or get it inspected by local authority?

Yep. You get to thank Uncle John Prescott for that.

the two choices you have are either to do it right (to BS7671 and to Building Regs) or not.

To do it right you have 2 options- DIY to BS7671 and local council inspection or use a registered contractor.

It's your money and your choice.