shower cable 6.0 or 10.0

[fabgav]

Hi all.

I was looking into what size cable needed for a 9.5kwh shower and the general consensus is to use 10.0

Having read why with regards to voltage drop, is it mainly down to if the cable is insulated anywhere?
(and the length of run)

My set up will be from CU, under floorboard cable will be sitting on the dirt/rammel that is under there, there is crawling space.
Then up and around a door in the under stairs cupboard in plastic trunking.
Then between ceiling and bathroom floorboard with no insulation,
Then up behind stud wall to loft, into pull cord switch and back down to shower unit.
Total run is 13/15 metres.

I've found a couple of calc's that suggest 6.0mm would be okay.


What are anyone's thoughts?
Apart from the 'If you need to ask you shouldn't be doing it' and the 'call an electrition' and the 'This work is notifiable'

Cheers

 

[EFLImpudence]

Being in trunking will mean you should use 10mm².

It is notifiable, will require RCD protection and should be properly tested for which you will not have the equipment.

 

[PrenticeBoyofDerry]

As above, trunking will factor a de-rating to cable, so 10mm2 T&E would be my cable of choice.
Plus the requirement for 30mA RCD and notification procedures, inspection, test & certs. Any buried cable should be within the permitted safe zones, also cables through joists and chasing in walls should comply to building regs part A

 

[fabgav]

Thank you both.

Surprised plastic trunking acts as such insulation, but then that's why I asked

Many thanks