How to extend ring main and where to channel cable (Domestic property)

[uptown47]

Hi all,

My daughter has asked me to put in a new socket for her. She would like it putting about 10ft from an existing double socket on the same wall. The floor is concrete and her upstairs has just been decorated (carpets etc) so I searched to see if it was acceptable to run mains cable behind skirting (underneath the plasterboard). It seems that this isn't acceptable.

However I found this image on another thread...



This image seems to indicate that it would be perfectly acceptable for me to channel the wall out sideways from the existing socket?

My first question is... is this correct? Is it allowed to channel out sideways from an existing socket in order to put another socket it?

I would preferably like to put the new socket on the ring main (rather than a spur) and I wondered what the accepted method for extending the existing cables in the socket are? Would something like this be suitable?
Debox In-Line Connector Box | Junction Boxes | Screwfix.com

The socket will be used to power a 2KW fire electric fire hence me wanting it on the ring main rather than a spur.

(As an aside.. my background is industrial electrics - working inside low voltage panels in a factory with either 24VDC or 415VAC three phase - I'm not up to speed on domestic wiring regulations - hence the questions - but I am able to operate the necessary tools to get this done and have the necessary respect for electricity not to kill myself or others in the process)

Thanks for any help you can give me on this.

 

[Darkwood]

Welcome to the forum

Yes horizontal on the same wall in line with an outlet is ok.
Any joint hidden within the wall will have to be maintenance free, the box and connectors shown in link do not comply.
As you are adding an additional socket you will have to install it to meet the latest reg's regardless of what regulations the original ring final circuit was wired under, this would mean it must have RCD protection for the cables you install (if cables are buried <50mm deep) and the socket itself must have rcd cover.
If you take out the original backbox and fit a deeper box you could make the ring joint in the back of that box on one leg to keep the additional socket as part of the ring, because it is accessible it can be done with standard connectors.

 

[uptown47]

Hi Darkwood,

A big thanks for the *extremely* fast response!

So, if I understand you correct, I'm ok to use the connector box I linked to as long as I have the connector in the back of the existing sockets backbox? Is that correct?

Cheers

 

[Octopus]

Well done for locating the image of the safe zones - this information is clearly ignored by so many people!

 

[uptown47]

Thanks Murdoch. I think, because I've not done 17th Ed (or any Ed for that matter) it makes me even *more* paranoid about doing the job right. That's why guys like yourself and darkwood and forums like this are a godsend.

Cheers

 

[Pete999]

If you look at Appendix 15 in BS7671, it is generally accepted that loads over 2KW would be better on a dedicated circuit of its own.

Doing it this way would alleviate the overloading of the Ring F C, I believe Regulation 433.1.204 refers although I don't have a copy available to check.

 

[uptown47]

I believe Regulation 433.1.204 refers although I don't have a copy available to check.

If you've just pulled that out of your head then I'm VERY impressed!! Well done that man!! lol

A bit thanks for that info Pete. I'm not actually sure of the fire power requirements at the moment as my daughter hasn't bought it but the one she was looking at was 2KW. I'll tell her not to go any higher than that (and, preferably lower) as to run another circuit from the distribution box would be a nightmare and I've absolutely no idea how I would get a cable from there to the living room?

Just as an aside... the distribution board is in a small porch with a concrete floor. And the upstairs is fully decorated with carpets etc. If you were running a new cable would you rip up the carpets etc upstairs and then channel up the walls from the distribution box?

Or is there a less disruptive solution? Like taking the cable up to the ceiling and then going along in that 150mm zone that is on the drawing (or does that just come into play for wiring in the same room)?

Just curious as to what the professionals do when it comes to installations like that?

Thanks again for all this great info. This is a really great forum and I've learnt a LOT from just browsing it this morning. I've already thrown away all my "socket safety covers" and emailed my two daughters to tell them to do the same. We put them in to protect our grand-daughters but it seems they cause more danger than they sort! (and when I think about it I can completely understand why - don't know why I didn't work it out sooner!).

Thanks again

 

[telectrix]

i'd join in the existing socket back box using these.... ideal in line splice connector.

https://www.youtube.com/watch?v=Kvhik0czv8s

and as ytje heater is not > 2kW, ( 9A), then it will be fine on the rfc. as previously stated RCD protection is a must, either just for the new cable andd socket or, better, for the RFC as a whole.

 

[uptown47]

Thanks telectrix. Those look like a great way of jointing the cable. They're only a couple of quid from Screwfix too so I'll definitely be going down that route.

Thanks again

 

[Deleted member 9648]

Another point is don't just assume that the socket you are extending from is on a ring....even if there are two cables. Test to make sure.

 

[uptown47]

I would never have thought of that wirepuller but you've made a great point.

What is the best way to check? Just test resistance between the two L's and N's and make sure it's only a couple of ohms?

 

[telectrix]

easiest way is ...

diss the legs ( L, N, and E, in the CU, measure end-end of all 3 conductors. then split at the socket you're connecting into and check that the end-end resistances are not there anymore at the CU. then, once you have connected the new socket , measure the end-ends again. then cross connect, measure R1+R2, then connect up, energise, get your Zs, job's a good 'un.

 

[uptown47]

Great stuff. I'll do that!

 

[Midwest]

Is it me, or is this turning into a diy, how to wire up a socket thread. No offence OP, but do you have the suitable knowledge & equipment to test your work after installation?

 

[uptown47]

Is it me, or is this turning into a diy, how to wire up a socket thread. No offence OP, but do you have the suitable knowledge & equipment to test your work after installation?

Hi Midwest

No offence taken at all. I do have the suitable knowledge to do this job and I can borrow a loop tester from work. But you're right, this is a DIY job as I didn't know what the regs said regarding how to tackle this (all sorted now thanks to the good folks here on the forum) and just wanted to make sure that I did everything correctly.

Cheers