Yes, there will be a sink. I shall earth bond that back to the new consumer unit.
My thinking re. earthing of the telephone box is that this is made of cast iron. Intention therefore is to earth bond this back to the new consumer unit too.
Hi EricMark - thanks for the advice. A P-nut sounds like a possible solution, with a cable from that to the earth block. The plastic of the new consumer box seems strong, so I'm sure this will work. As to my other questions, I think I can see what's what, but one learns through repetition and...
I hope that someone can help. The first garage to my house has power, with its own consumer unit, with a 100amp main switch, and spare MCB slots. I can completely isolate this consumer unit at the main board, where's there's an RCD for it.
The second garage is a few metres away from the first...