Loft space has a 10mm T&E cable terminated into a JB in the loft space which was from a old shower being removed. The requirement is for a oven and microwave being installed into a new space at back of kitchen where only a 13Amp socket is available. The current draw would be 22Amps. The new cable will be pulled through a 1st floor down in to the kitchen through the cavity wall. Shall I take the new cable down as 10mm or drop down to 6mm and change the MCB at the CU to 32Amp????? The full cable run is around 30Mtrs.