In article ,
David Hearn wrote:
Can anyone advise what depth backbox I should use? I'm adding a 2G MK
socket, and was planning on using 25mm - however after reading the
instructions it said that for = 9mm face plates, use 25mm, and 9mm
use 35mm. I think the 2G MK socket is about 9mm - but I just wondered
what the benefit was with going with 35mm, and whether 25mm is very
cramped (2x 2.5mm T&E). Its an internal block + plaster wall (1930's
block), so I don't want to go too deep (not to mention that the deeper
I go, the more work it is!).

Is 25mm a bit shallow?

To me, yes. So I always use 35mm for sockets. It's not that much more
work, really.

One final thing - when I fitted some before, I set them too deep as I
thought they should be plastered into place. I think they should be
screwed into place and made good with plaster (rather than 1/2 - 1" of
plaster being the thing to hold it in place) - am I correct?

It's often a little tricky drilling a hole *exactly* in the right place in
some types of brick and block work. And the back of the recess is likely
to be a bit uneven - if you're anything like me. ;-) So a dollop of quick
set mortar can be an easy way - with the box wedged exactly in place until
it sets. Then make good the plaster with that one coat stuff.

--
*He's not dead - he's electroencephalographically challenged

Dave Plowman London SW
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