Practical advice on adding a socket to ring main

[JohnW2]

If I understand you correctly, then that is precisely what I suggested, and is fine provided there is room in the existing socket's back box for the necessary connections. I'll see if I can produce a sketch for you.

How about (pretty rough!)
....

Kind Regards, John

 

[JohnW2]

Why ? , as far as I understand that method is compliant with the regulations.

It would be, but it would involve a lot of unnecessary extra work (to widen the hole for the back box) if, as is likely, the existing socket is mounted on a back box.

Kind Regards, John

 

[bernardgreen]

I agree widening the hole by a few millimeters is necessary but it avoids the need to squeeze a connector into the box behind the socket.

Getting a suitably rated connector in the existing back box may not be possible if it is a shallow box. Widening a far easier than making the hole deeper to get a deeper back box in.

 

[neocleous]

How about (pretty rough!)
....
View attachment 164372

Kind Regards, John

That all makes sense to me. I have flat screw less sockets so the ring main extension will in all likelihood work better for me as 4mm2 cable to create a spur will be very stiff and most probably bend the socket outward in the middle.

My only question is if I am able to replace the cable going to the next socket rather than having a joint can I run the unbroken cable through the existing sockets back box? I tried to ask this earlier but I don't think I was clear enough.

Same wiring as in your diagram but no joint which is my preference and yours by the sound of it. No guarantee this will be possible until I start exploring I would just like to know the options before I start.

Thanks

 

[neocleous]

I agree widening the hole by a few millimeters is necessary but it avoids the need to squeeze a connector into the box behind the socket.

Getting a suitably rated connector in the existing back box may not be possible if it is a shallow box. Widening a far easier than making the hole deeper to get a deeper back box in.

Two singles isn't an option in this case as the socket wouldn't match and that would annoy me more than taking a chisel to the wall and putting a deeper back box in.

It's good to know though in case I come across this situation again.

Thanks

 

[EFLImpudence]

OR

If it were for a customer - ripping off comes to mind.

 

[JohnW2]

That all makes sense to me. I have flat screw less sockets so the ring main extension will in all likelihood work better for me as 4mm2 cable to create a spur will be very stiff and most probably bend the socket outward in the middle.

Fair enough - although I have to say that there is really very little difference between the 'usability' of 2.5mm² and 4mm² cable - the stiffness one might gain by the larger CSA of 4mm² is largely offset by the fact that its conductors are stranded, not solid.

My only question is if I am able to replace the cable going to the next socket rather than having a joint can I run the unbroken cable through the existing sockets back box? I tried to ask this earlier but I don't think I was clear enough. Same wiring as in your diagram but no joint which is my preference and yours by the sound of it. No guarantee this will be possible until I start exploring I would just like to know the options before I start.

Avoidance of joints is, where possible always desirable. However, what you propose could represent a fair bit of extra work (the existing sockets are quite probably fed from under the floorboards), so I'm not sure that I would personally bother (unless the floorboards were going to have to come up for some other reason).

Kind Regards, John

 

[neocleous]

Fair enough - although I have to say that there is really very little difference between the 'usability' of 2.5mm² and 4mm² cable - the stiffness one might gain by the larger CSA of 4mm² is largely offset by the fact that its conductors are stranded, not solid.
Kind Regards, John

Ah yes I hadn't factored that in! I'll take the sockets off and take a look where they are fed from and confirm it is indeed a ring main, I've got a few possible installation options now.

Thanks for the tips and suggestions everyone.

Thanks

 

[EFLImpudence]

2.5mm² is stiffer than 4mm².

 

[neocleous]

2.5mm² is stiffer than 4mm².

I'll probably give that a go first then, sounds like it will be less work

 

[TomH93]

It’s also worth looking which way the cables come into the back box. If it’s downstairs then it very likely to be coming from above. If this is the case you could use one leg feeding the existing socket to power your new socket and fish a new piece of 2.5mm from the new socket to the existing socket. A spur could then be taken from the new socket to supply another socket.

If you able to pull the existing cables with the power off and they move in the wall then it will be even easier to do this!

Obviously you would also need to be very careful to not damage the cables when cutting in your new socket.

 

[EFLImpudence]

It’s also worth looking which way the cables come into the back box. If it’s downstairs then it very likely to be coming from above.

He says it is a bedroom with floorboards, but still unlikely to come from above.