I need to supply power to my back shed approx 40m away.
I know i need to to go down 500mm but part of the way will be behind a a retainer wall. My question is: if i continue the depth from the house (500mm) behind the retainer wall it will be 1.2m buried. Can i raise the depth of the cable to 500mm when its behind the retainer wall or do i need to continue at the depth i started from at my house level?