Can backbox sit proud if reskimming?

[NHW]

So I'm just chasing the sections for my new backboxes. They are 25mm deep and I've basically managed to chase the plaster depth pretty OK (hitting upto the brick).

When I put in the backbox now it sticks proud about 9mm. The entire wall is getting reskimmed anyways so that will bring it out anywhere around 5-8mm. So in theory that will only make the backbox proud by 1mm or possibly flush. Will this be adequate?

I'm only asking because to chase in this was only around 30 mins Inc measuring up and leveling etc. But if I have to knock out brick in order to get it deeper I can see that taking wayyyyyy longer, easily another 30-60mins per outlet. Multiply that by 10 and its quite alot of extra time I could save.

Have included a picture for reference

Again I'm not an electrician or anything, I'm just chasing up the walls and an electrician is coming in to do the actual wiring part since I would always use a professional for that part.

Any advice is appreciated

 

[mattylad]

NO.
1mm proud is too much, if it was recessed by 1mm then that would be fine but not sticking proud.
The faceplates will never fit flush with the wall and that thick is AFAIK not skimming, that's way too much for simple skimming.

What are you knocking the brick out with, paper straws? Get an SDS chisel onto it or drill it.

 

[Mr Chibs]

What about putting 9mm of skim on

Get the chisel out and dig it deeper, levelling it is not paramount, as there is adjustment when faceplate is put on.

 

[johnny2007]

Get a proper back box cutter set and do the lot in half hour.

 

[Wayners]

Dig deeper

 

[flameport]

As above - they need to be flush, anything sticking out is no use and 9mm will be a total mess.

25mm backboxes are not to be recommended either, far better to do 35mm which will allow for flat plate decorative accessories, USB outlets and all the other things which won't fit into a 25mm.

 

[NHW]

Thanks guys, went and got an SDS hammer drill and went through with it and got it flush pretty quickly tbh. Obviously mine was timesaving thinking at first but if to do it properly required it then definitely doing it. I got it to fit a 25mm box in but I'm guessing I need to go with 35 if I'm using it for plug sockets? In that case mind if I ask why the 25mm exist for sockets if 35mm is recommended? Just general curiosity. Thank you

 

[chivers67]

I was just about to post about getting an SDS Angle bit to do it! You can get some that are the same width as back boxes

Some sockets and accessories are ok with 25mm but I learnt the hard way a number of years ago and now fit 35mm as standard.

 

[NHW]

The backboxes I actually got was 25mm's metals

This is also the faces that I got too which say 25mm metal or 35mm dry lining box (guessing for plasterboard)

Slimline 13A 2 Gang Switched Socket with 3 USB Ports (1 x Type C + 2 x Type A, 4.0A) | DETA Electrical

Slimline 13A 2 Gang Switched Socket with 3 USB Ports (1 x Type C + 2 x Type A, 4.0A)

www.deta.co.uk

So I guess 25mm will be ok but again since I've got this drill out already and I'm only going to do it once I'd rather just take the 25mm back and go for 35mm's now. I'm assuming that going back 35mm will not affect the structural integrity of the wall itself? Probably a stupid question I know but just thought I'd ask. Thanks all

 

[davelx]

Get a proper back box cutter set and do the lot in half hour.

Tried one of those - fine on breeze block,etc, useless on 1930's bricks. Stitch drill and SDS chisel for me.l

 

[johnny2007]

Tried one of those - fine on breeze block,etc, useless on 1930's bricks. Stitch drill and SDS chisel for me.l

You probably bought a cheap set.
I have used Armeg set for years and goes through anything.

 

[davelx]

You probably bought a cheap set.
I have used Armeg set for years and goes through anything.

Quite possibly - it was a long time ago, can't remember what brand it was.

 

[SUNRAY]

Opinions on Bosch SDS chisels?

I dug out some garage very hard concrete floor for sewer pipes, took the edges straight off.

 

[flameport]

So I guess 25mm will be ok but again since I've got this drill out already and I'm only going to do it once I'd rather just take the 25mm back and go for 35mm's now.

Some sockets will fit on 25mm - assuming they are the style which stick out from the wall by 10mm or so, and there are only one or two cables behind, and those cables enter in appropriate places where the socket has room for them.
However the extra 10mm makes a huge difference in ease of installation, and will accommodate pretty much all sockets and other items.
A small amount of extra effort now to fit 35mm will make all the difference later on when someone decides they want flush plate affairs after the wall has been decorated.