From the exteranl electric meter cupboard/incoming supply the wires run inside a stud wall to an internal RCD board in a small cupboard in my hallway.
This is very drafty.
I cannot insulate/plug any gaps behind the meter, so wondered if it is safe to carefully insulate around the RCD - obviously taking care not to disturb incoming or outgoing wires.
Planned on using rockwool fibre but concerned if it may cause overheating?
There is not eough room to insulate the cupboard door - have already thought of that.
No not safe. The consumer unit is a type tested distribution unit and you are only allowed to fit parts recommended by manufacture. The RCD has electronics inside which will be sensitive to heat and the current going through the device will cause it to heat up. With the MCB's they get even hotter.
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