I have just had a gable end wall damp proofed by having the old wet plaster removed , a waterproof membrane added (Newlath 500) which has had plaster board added using dot and dab and finished with Thistle final top coat about 3mm thick.
The existing wall double-socket box has to be replaced as it is too corroded to keep. Unfortunately the hole cut out of the plaster board is too large (this became evident when removing the old box) . The hole had been made smaller by the use of mesh tape and plaster around the opening which is not strong enough to enable me to screw in the socket face without crumbling the plaster around it's perimeter.
How do I overcome this problem? One thought was to use a 2 to 3 converter socket face which would then extend further out each side onto proper plaster board. Alternatively a plastic surround which fits over the plaster board and under the socket face would enable me to use my existing double socket and negate the need for making good the edges. Unfortunately I have not been able to find such a product at our local B & Q store, only ones for light switches.
Any advice would be much appreciated.
Shaun