Hi all

When fitting an electrical socket, should the edge of the mounting box be
flush with the outer surface of the wall?

So for example, if your plasterboard is 10mm thick fixed onto 25mm batten,
should you use 35mm mounting boxes.

Or can you get away with using 25mm mounting boxes?

I would like to fit all my mounting boxes before I fix the plasterboard. I
was hoping that once the plasterboard was fitted I could just drill and open
up the hole over the mounting box. However, if the mounting box was 35 mm I
wouldn't be able to fix the plasterboard on (unless I had created the hole
in the plasterboard first - which I don't want to do)

Thanks for your time.