Acceptable additional socket configuration

[TheMrX]

I've seen a few other posts on the forum relating to this but none seem to clearly answer my question (with a diagram).

If I want to add a new socket to my ring main is the following acceptable? Blue is existing cables/sockets and red is new.

Thanks for your help.

Untitled

• TheMrX
• 18 Mar 2009
• 2

 

[nitro23456]

why 2 junction boxes?

 

[kevindgas]

why would you need 2 JB's ? use existing cables one to old socket one to new socket and add a fresh bit of wire between sockets
or is there something your not telling us

 

[securespark]

2 jb's because he needs to join the existing cables (in blue) to the new cables (in red). I can only assume the drop to the L/H socket cannot easily be replaced, nor the leg coming from the right.

 

[ericmark]

According to Spring Wiring Matters by IET it seems if we extend a ring main the whole of the circuit must comply with BS7671:2008 i.e. RCD on all sockets under 20A.
However the position as far as a spur seems less clear and you may be allowed to only protect new wiring to BS7671:2008 and old can be left as it was.
In view of that it may not be prudent to extend a ring main. However before extending any ring or connecting a spur you will need to know the ELI of the circuit and see if it is low enough to be able to add to it.
If you have RCD protection there is likely no problem but without RCD protection it is not straight forward.
Remember all tests do need to be carried out there is no get out of jail free card if you DIY rules are same for the trade and DIY.

 

[TheMrX]

nitro23456 and kevindgas the reason for 2 JBs is exactly for the reason that securespark mentions, and certainly nothing to do with hiding information. I'm asking for genuine advice not how to do a dodge job that could risk my home and family.

ericmark I have RCD protection and thanks for the other info.

So all in all this IS acceptable???

 

[electronicsuk]

So all in all this IS acceptable???

If the JBs are 30A rated and kept accessible, I see no problem with it, assuming you comply with all other relevant regs in BS7671 and with your local building codes, although it may be a little 'inelegant',.

 

[ericmark]

Yes

 

[rebuke]

Just to emphasise/clarify what electronicsuk said - your junction boxes must be accessible, i.e. you can't just shove them under a floor, unless it has an appropriate inspection hatch in the right place. In a loft space is OK (as long as you don't board over them) - where are you planning on putting them?

 

[TheMrX]

rebuke They will be in the loft space, which isnt boarded out, so will be connected to a joist up there. (And like the cables, above the insulation!)

Thanks all. Feel a lot happier about doing this now. Cheers.

 

[kevindgas]

certainly no intention of implying you were doing a dodge. I just questioned the need of 2 jb's as it shouldn't be that difficult to remove 1 wire and pull a fresh one in at the same time. but no problem with doing it your way though just i wouldn't do it (for no other reason than i prefer not to use them)

 

[nitro23456]

nitro23456 and kevindgas the reason for 2 JBs is exactly for the reason that securespark mentions, and certainly nothing to do with hiding information. I'm asking for genuine advice not how to do a dodge job that could risk my home and family.

ericmark I have RCD protection and thanks for the other info.

So all in all this IS acceptable???

Explain to me how I have encouraged you to bodge the job and endanger your family?

You don't need two junction boxes as has been pointed out but your way is acceptable.