Boxes and dry lining

[milliamp]

Hi guys,
I do not get involved with a lot of new build work so I would not know what the preferred practise is with installing socket/switch boxes under the plasterboard.
The local builders are quite happy to have the boxes screwed directly to the blocks, but a new dry lining fella is making a bit of a fuss because he has to dab out the board a bit.
Which is the "current best practise"?

Thanks for your answers

 

[GaryMo]

I always screw 25mm metal backboxes directly to blockwork without chasing in. Plasterers we work with don't have a problem, 12.5mm plasterboard and dab soon gets to 25mm.
Your cables and capping won't be far off the other 12.5mm anyway.
Never had a proud box yet, don't so new-builds on site though where plasterers may want to limit the amount of materials used

 

[Lectrician]

Every boarder is different.

We can usually get away with a 25mm direct to block, but at times get boarders that winge.