My brother has moved in to a new (to him) house.
The house has been rewired in I guess the last 10 years.
Many of the 13Amp sockets are mounted on the skirting board - (boxes - not flush mounted).
He (with my help) would like to move them about 1 foot up the wall.
There is no slack in the cables serving the existing sockets.
What is the correct way to do this.