Electric Supply to Garage/ Annexe

[clarabel]

Hi,

I have just about finished the main build of my new garage with upstairs annexe and need to bring power to it from the house.
I plan to have a couple of wall heaters an electric shower and a small cooker in the annexe apart from the usual low draw extras, I have laid a 4mm2 armoured three core for the annexe.

The supply to the house is a PME can i just connect the the armound via service to the service blocks that are by the meter in the house already or do I need to fit some form of MCB for the annexe supply?.

Rgs

 

[GaryMo]

You'll need short circuit protection and correct overload protection so a 32A MCB would be required for that size of cable depending on other factors (normal SWA or XLPE, length of run for volt drop, installation method, ambient temperature, grouping factor, thermal insulation).

What's the rating of your electric shower, cooker and wall heaters?
Your cable could be potentially (probably) undersized.

What's the size of your main fuse? Have you calculated maximum demand for the existing house and for the new supplies?
Is your supply adequate for the new combined loading?

 

[Lectrician]

4mm? Umm - not good.

Seriously, what size shower, cooker, heaters?

 

[securespark]

Is it attached to the house?

If so, take all final circuits back to the main intake and incorporate all circuits into one consumer unit.