Suggested Route and cable size/rating

[spudz]

3 questions -
- Is my suggested route ok?
- Is the 6mm cabling suggestion ok?
- Would it be much different/cheaper if I stuck with a 13amp Hot Tub?


I am fitting some plasterboard and cupboards in a garage that is attached to the house.
The consumer unit is also in the garage.
I want to have power to the outdoor patio and Hot tub. I would like to install suitable cable(s) behind the plasterboard now ready for the electrician to use in the future. I would like your advice on the best way to do it and the best cable size to use.

I am thinking of running the cable(s) internally (behind any plasterboard/cupboards), so up from the Consumer Unit to the safe zone within 150mm below the ceiling, around the two walls and then down to near the floor where it will exit through the wall to an external box. Then SWA to the patio and Hot tub either clipped along house wall below the dpc or dug into a trench.


The supply for the Patio should have enough power for a small outdoor kitchen (perhaps, electric BBQ, hotplate, Kettle and maybe two 2KW patio heaters) Unlikely, to be using heaters while cooking.
Current Hot Tub is 13A plug and Play type but I am wondering how much more expensive it will be to have a 32amp supply for future proofing
There is a existing outdoor socket close to the Patio but probably of little use (maybe the patio wall heaters or the 13amp hot tub??)

- Internal run from CU to outdoor box 12m
- External SWA from box to Patio 14m (A in photo)
- External SWA from box to Hot Tub 16m (B in photo)

A brief conversation with the guy at the counter in electric suppliers suggested running two 6mm Cables internally and out to the Wiska box then two 6mm SWA to the Patio and Hot Tub with IP65 Rotary Isolator switch.


Very much appreciate any advice/guidance and open to alternative suggestions

 

[ericmark]

Question one has to be, what will the earthing method be? The rest hinges off that.

There are two types of earth used in the UK, TT and TN, the TT uses an earth rod, and TN the earth comes from the supplier.
The TN can be further split into TN-S and TN-C-S.

It is important that no one can touch two different earthing systems at the same time, and the TN-C-S system has a problem should the PEN be lost. In some situations TN-C-S is not permitted, but in the main it is better than TT.

So step one is to ask the electrician what is required, it is not easy, and so until that is sorted, everything else is on hold.

 

[spudz]

Cheers Eric,
I did have a paragraph about earthing in my original draft but deleted it as I thought my question was getting too wordy.
I haven't got an electrician yet, we are getting a lot more work done on the property so will go with the builders electrician or recommendation.
How will he determine our earthing system, a visual inspection of the earthing around the consumer unit and meter cabinet?
Will either earthing system dictate the cables I put in the garage?
I just wanted to put the cables in around the corner of the garage before it gets plasterboard this weekend.

 

[EFLImpudence]

So step one is to ask the electrician what is required, it is not easy, and so until that is sorted, everything else is on hold.