Fitting a back box before or after skim?

[matt84]

Hi

We're moving into a property that needs a skim (some old blown plaster) but whilst we're at it I'm going to going to get rid of the wall mounted sockets and fit metal back boxes so obviously I'll be drilling through the old plaster/brick to fit this.

Here's where I'm stuck.....

Have the skim done then do the chiselling and fitting and make good myself or fit the back box whilst the walls are in need of a skim?

I know nothing about plastering and just thought if I fit it flush before the skim then it would be installed below the plaster when the skim was finished or would I leave it a bit proud so the skim matched the level of the back box?

Thanks!

 

[Adam_151]

Definatly before, no two ways about it, and you'll probably have to rough fill the chases/around the boxes before plasterer comes unless you have arranged for him to do this otherwise you'll mess his schedule up...

Dont worry if the box is recessed in a few mill rather than spot on with the plastered surface, thats normal, what you dont want is for it to be sticking proud of the finsihed wall

 

[Taylortwocities]

Here here.

Fit boxes then plaster.

In the morning, you don't put your shoes on before your trousers!
(Or do you?)

 

[PrenticeBoyofDerry]

No disrespect, but are people really that illogical?

 

[matt84]

Thanks for the replies.

It's nothing to do with being illogical, it's not knowing whether fitting a back box prior to a skim would cause the faceplate to be sunk into the finished plaster, I don't know the thickness of a skim.

Thanks again for the tips.

 

[securespark]

In the morning, you don't put your shoes on before your trousers!
(Or do you?)

Hey!

I have been known to do that...

 

[PrenticeBoyofDerry]

Thanks for the replies.

It's nothing to do with being illogical, it's not knowing whether fitting a back box prior to a skim would cause the faceplate to be sunk into the finished plaster, I don't know the thickness of a skim.

It would hardly matter much if the backbox were recessed, it is more important that it is not proud of the wall.
Plastering is the final stage prior to decorating, so if you intend to sink things in to walls, do it prior to plastering.

PS, skims would normally be about 3mm.

 

[JohnW2]

It's nothing to do with being illogical, it's not knowing whether fitting a back box prior to a skim would cause the faceplate to be sunk into the finished plaster, I don't know the thickness of a skim.

The faceplate is tightened onto the surrounding plaster, not the back box, and it doesn't matter if there is a bit of gap between faceplate and box - the screws are quite long (and longer ones are available!). If the box were flush with the wall prior to skimming, that would be fine.

Kind Regards, John

 

[PrenticeBoyofDerry]

The only real exception, would be if you were using grid modules, were it is a damn site easier if the backbox is level with the finished wall.
So if you intend to fit any grid modules be a little more exact!

 

[JohnW2]

The only real exception, would be if you were using grid modules, were it is a damn site easier if the backbox is level with the finished wall.

Agreed.

Kind Regards, John

 

[PrenticeBoyofDerry]

the screws are quite long (and longer ones are available!).

And if you have got some fancy face plates with matching screws and the screws are too short, you can use extension studs with the fancy screws.

Untitled

• PrenticeBoyofDerry
• 27 Nov 2013
• 1

 

[ban-all-sheds]

In the morning, you don't put your shoes on before your trousers!
(Or do you?)