Socket Backbox Problems

All your electrical questions regarding electrics from within the United Kingdom

Moderator: Moderators

Post Reply
J Kelly
Newly registered Member
Posts: 6
Joined: Wed Apr 04, 2018 11:17 am
Has thanked: 3 times
Been thanked: 0

Socket Backbox Problems

Post by J Kelly » Wed Apr 04, 2018 12:01 pm

Hi all,
I'm Trying to change a surface mount socket to a recessed socket. I have managed to change 2, however on the last one I have a problem after marking and cutting the recess, a hole has appeared in the breeze block or (something that resembles a breeze block), I think the cavity is right behind it, although I'm not even sure it is cavity but just a design of the block. It is a party wall, but judging from the outside brickwork it is one breeze block thick. I need to fit a 35mm box as the old wiring is thicker and harder to get in a 25mm box. any ideas?

Thanks.
Attachments
IMG_20180330_131124 (Custom) (Custom).jpg
IMG_20180330_131124 (Custom) (Custom).jpg (221.19 KiB) Viewed 1019 times
IMG_20180329_184651.jpg
IMG_20180329_184651.jpg (189.85 KiB) Viewed 1019 times
User avatar
Kev888
Senior Member
Posts: 413
Joined: Wed May 14, 2014 1:38 pm
Location: Derbyshire
Has thanked: 73 times
Been thanked: 52 times

Re: Socket Backbox Problems

Post by Kev888 » Wed Apr 04, 2018 2:15 pm

If I'm interpreting correctly, your excavation has barely gone beyond the plaster so far. Are the holes just the old socket's screw holes or did they really appear with such a shallow cut? And/or is the problem that the hole shows only a very thin depth of block?

It depends on just how thick it is, but some blocks are hollow (sometimes filled with insulation). But certainly don't assume the wall is double thickness with a cavity. It is quite normal to just have the one thickness of brick or block.
These users thanked the author Kev888 for the post:
J Kelly
Rating: 7.14%
Kev
J Kelly
Newly registered Member
Posts: 6
Joined: Wed Apr 04, 2018 11:17 am
Has thanked: 3 times
Been thanked: 0

Re: Socket Backbox Problems

Post by J Kelly » Wed Apr 04, 2018 3:16 pm

Thanks for the reply,
Yeah the picture is a bit deceiving, on the side you cant see, I have dug out about 20-25 mm actually Into the block. Then started digging out the side where the hole is and which I think must have been the rawl plug hole to secure the old backing and noticed I can see what looks like either the cavity wall or the block is like the picture below. Just wondering how to go about it, if I knock the thin bit of block out,

Thanks
Attachments
P6260012 (Custom).JPG
P6260012 (Custom).JPG (317.92 KiB) Viewed 991 times
User avatar
wine~o
Senior Member
Posts: 24690
Joined: Sat Jan 10, 2009 3:49 pm
Location: hants/dorset border
Has thanked: 1325 times
Been thanked: 3632 times

Re: Socket Backbox Problems

Post by wine~o » Wed Apr 04, 2018 4:00 pm

:welcomeuhm:

Keep hacking away and be prepared to say "hello" to your neighbours... :lol:

Kidding.

If it is a hollow block then a suitably sized lump of wood can be employed (siliconed to the block) to screw the back box to.
These users thanked the author wine~o for the post:
J Kelly
Rating: 7.14%
Verwood Handyman

Verwood Handyman


___________________________________________________________________

If you feel you have benefited from the Free advice given on the Forum, Please consider making a donation to UHM's Nominated charity, read all about it and donate here :

http://www.donnasdreamhouse.co.uk
User avatar
Kev888
Senior Member
Posts: 413
Joined: Wed May 14, 2014 1:38 pm
Location: Derbyshire
Has thanked: 73 times
Been thanked: 52 times

Re: Socket Backbox Problems

Post by Kev888 » Wed Apr 04, 2018 4:40 pm

Yeah, I agree. Glue in a bit of timber, certainly don't drill/screw it into a thin skin on next door's side. Sometimes blocks are like those you pictured, but only one brick width - its more rare, but in that case the depth could be quite small.

This is all assuming next door haven't done something odd anyway, like make a big recess in exactly the same place you're doing!
Last edited by Kev888 on Wed Apr 04, 2018 4:42 pm, edited 1 time in total.
Kev
J Kelly
Newly registered Member
Posts: 6
Joined: Wed Apr 04, 2018 11:17 am
Has thanked: 3 times
Been thanked: 0

Re: Socket Backbox Problems

Post by J Kelly » Wed Apr 04, 2018 4:41 pm

wine~o wrote::welcomeuhm:

Keep hacking away and be prepared to say "hello" to your neighbours... :lol:

Kidding.

If it is a hollow block then a suitably sized lump of wood can be employed (siliconed to the block) to screw the back box to.
Haha, Yeah I know the walls are pretty thin, but don't really know if there's a cavity there or how its built. Was going to just knock through and do what you suggest with wood, but am concerned if it is some kind of cavity and if so would it present any problems..fire risk or anything. What's left of it seems I could just tap it with a screwdriver and it would just fall out.
J Kelly
Newly registered Member
Posts: 6
Joined: Wed Apr 04, 2018 11:17 am
Has thanked: 3 times
Been thanked: 0

Re: Socket Backbox Problems

Post by J Kelly » Wed Apr 04, 2018 4:45 pm

Kev888 wrote:Yeah, I agree. Glue in a bit of timber, certainly don't drill/screw it into a thin skin on next door's side. Sometimes blocks are like those you pictured, but only one brick width - its more rare, but in that case the depth could be quite small.

This is all assuming next door haven't done something odd anyway, like make a big recess in exactly the same place you're doing!
Yeah, seems I could do that. I did look on the neighbours side and there were no obvious signs of something being in the way. no sockets or pipes anyway. Just concerned having part of it in a hollow void or cavity.
User avatar
Kev888
Senior Member
Posts: 413
Joined: Wed May 14, 2014 1:38 pm
Location: Derbyshire
Has thanked: 73 times
Been thanked: 52 times

Re: Socket Backbox Problems

Post by Kev888 » Wed Apr 04, 2018 5:15 pm

In some cases there isn't much choice (in fact in things like stud walls it is inevitable), but of course you will be filling the hole with a metal back box. You could additionally seal/glue around the back-box, to help prevent drafts & dust etc getting so freely past the edge of the socket.
These users thanked the author Kev888 for the post:
J Kelly
Rating: 7.14%
Kev
J Kelly
Newly registered Member
Posts: 6
Joined: Wed Apr 04, 2018 11:17 am
Has thanked: 3 times
Been thanked: 0

Re: Socket Backbox Problems

Post by J Kelly » Wed Apr 04, 2018 5:21 pm

Kev888 wrote:In some cases there isn't much choice (in fact in things like stud walls it is inevitable), but of course you will be filling the hole with a metal back box. You could additionally seal/glue around the back-box, to help prevent drafts & dust etc getting past the edge of the socket.
Yes, I think that's what I'll have to do. Attach a block of wood with silicone or grip fill? and screw the box to that. I'll see tomorrow when I knock it out I guess.
J Kelly
Newly registered Member
Posts: 6
Joined: Wed Apr 04, 2018 11:17 am
Has thanked: 3 times
Been thanked: 0

Re: Socket Backbox Problems

Post by J Kelly » Wed Apr 25, 2018 8:38 pm

Thanks for your help, finally got round to fit it. After knocking through, sawed off a bit of CLS and stuck it to wall with a bit of bonding mixed with cement and screwed the box to that. I cut it to size so I could fit a 35mm box in. I did try Pinkgrip but it didn't seem to work, but sorted now.
OnlyMe
Approved Electrician
Posts: 2840
Joined: Sun Apr 24, 2011 6:01 pm
Location: South Yorkshire
Has thanked: 180 times
Been thanked: 610 times

Re: Socket Backbox Problems

Post by OnlyMe » Thu Apr 26, 2018 6:40 pm

Kev888 wrote:If I'm interpreting correctly, your excavation has barely gone beyond the plaster so far. Are the holes just the old socket's screw holes or did they really appear with such a shallow cut? And/or is the problem that the hole shows only a very thin depth of block?

It depends on just how thick it is, but some blocks are hollow (sometimes filled with insulation). But certainly don't assume the wall is double thickness with a cavity. It is quite normal to just have the one thickness of brick or block.
The simple way to decide if it is single skinned (very rare IMHO) is to measure from your window /door frame to the party wall and do the same with your neighbours widow/wall. Add the two together and subtract from the distance between your window/door and the neighbours. 11 inches and it's a cavity wall.
Post Reply

Return to “Electric Forum UK”