Moving cables and sockets/switches over insulation

[Camerart]

Hi,
I'm about to reroute cables and sockets/switches from the ceiling down to the socket height after insulating a wall.
I understand this will derate the cable, so what it the best way to do this please?

EDIT: Should be in DIY
Camerart

 

[Lou]

WELCOME I have had the thread moved

 

[Rockingit]

Hi,
I'm about to reroute cables and sockets/switches from the ceiling down to the socket height after insulating a wall.
I understand this will derate the cable, so what it the best way to do this please?

EDIT: Should be in DIY
Camerart

You'll have to give some more info! Is it that you have an existing wall with existing cable and socket, and that you're basically just adding insulation over the top?