I think this is fine but thought I'd ask just in case..
Martin Williams 14/09/2026 - 10.36 AM
Hi, I have recently moved a 2G socket literally two/three inches up from it's original location just above a boxed in section as you couldn't get any plugs into it. I have sunk a 2G back box into the wall a couple of inches above the existing one, run a small conduit between the two, and fitted a new double socket in the new location, with the cable running down into the old back box, connected to the existing cable with a 30a terminal block, and a blanking plate put onto the original backbox/socket. After doing this however a few things crossed my mind... The cable to the original 2G socket was I assume a spur... as there was only the single cable going to it, and it it protected by a 32a at the fuse board, when originally inspecting the original cable it looked a little thicker than modern 2.5mm t&e (it was solod core though) and as I was not absolutely certain to what size it was I used a small length of 4mm between the two.. I assumed this was all ok. So basically I have an existing spur, and I have 'extended it right..? not spurred off a spur..?' and the 4mm is ok..? or not..? if not I'll just take it all out or alter it. Many thanks for any advice, much appriciated.
Are you a tradesperson and able to answer this question?
There is a possibility given the information you have given that this circuit is not a ring but a 4mm radial.
In either case what you have done is fine if it is a spur from a ring you have just extended it which is allowed.
You did the right thing using 4mm that way if it is a 4mm radial circuit you have used the correct cable.
Terminal blocks are a bit old hat, though fine if installed correctly but would recommend you use Wago connectors especially for DIY as they are easier to use and less likely to cause issues.
Technically this is an alteration to the circuit and though well within the scope of DIY there are several aspects you may not have considered when doing this. RCD protection in place and tested, adequate earthing to the installation and the condition of the wiring you are extending.
If you are unsure on any of the above I would recommend you hire an electrician to check everything is safe and compliant. They have specialist equipment that can do the necessary checks.
Hi, yes you have only extended the cable, ideally if you had the same size cable it would be the same size through out the circuit, if you’ve used a short piece of 4mm cable that is not a problem.
Hello there,
Firstly, it's unlikely that the existing cable is larger than 2.5mm2 if it is solid core T&E. This would mean you have mixed conductor sizes in the terminals, which is unacceptable.
Secondly, you would have to inspect where the cable came from in order to know you do not have a spur from a spur or if indeed there was a ring in the first place.
These are just two of the situations where DIY electrics can cause issues. Whilst I'm on the side of liberty I cannot in all good consience condone DIY in this situation.
Best regards
DES
