Speculation, changing a single ring main across two floors,

[garethg]

Hi,
This needs a lot of speculation and guess work, but, you lot would know a lot better than I.

The house is a 3 bed Semi, two floors, 1 loft.
How much access would be required to change the wiring so that the current single ring main, was replaced by two, one per floor.

Why? When the house was bought, it was mentioned in the survey that there were too many sockets for the ring main (off the top of my head, 32A RCD, and around 11 single and double sockets throughout the house, some might be spurs, I can't really decide either way on this). This was a minor point, I believe that so long as the ring isn't touched, this was OK previosly and due to current regs may not be suitable.

I would like to add two to three more sockets. They would be good as spurs, they really are just moving what would be plugged in with extension cords currently in the rooms. However, I believe that this is too much (it would only be 1 per room, I actually layed in spur cabling when I had the floorboards up for another task).
The house is in a decent state of repair. If we were to get an electrician in to split the system into two rings, how much 'damage' is likely to be required?

I cannot see definitely which cable it is leaving the consumer unit. There are two 10mm cables, I suspect shower and cooker, and I think 4x 6mm cables.

I do not know the age of the cabling, all I can state it is definitely black/red, but this doesn't help much. Would it be a requirement for the electrician to remove all the current black/red (or is it just any 'new wiring' needs to be blue brown), and if so, as this is in conduits in the walls, is there likely to be damage due to this?
Thanks,

 

[breezer]

cant say withoiut seeing it and finding out what goes where.

expect the worst then when it doesnt happen you will be fine

 

[333rocky333]

If it was in T + E
Find socket near centre of ring in a room that you want an extra one,

Leave one existing wire there,remove and divert other existing wire to the new socket.

Run new cable back from existing socket to CU, and run one new cable back to CU from the new socket.

On the run back to board pick up any othr new sockets.

Part the two existing cables at the board and pair up with relevant new cable.

Creating two circuits

 

[garethg]

If it was in T + E
Find socket near centre of ring in a room that you want an extra one,

Thanks,
Finding one in the middle of the ring might be the difficult part. It also might cause the ring to be one front, one back, depeding on who/how the wiring was done, is this an issue (I guess not really, anyone sensible would check the socket first right??)?

So it shouldn't be necassary to re-wire the place to bring it to current colouring/standards, most of the wiring doesn't look damaged, just dusty!

 

[breezer]

to bring it to the "new colour standards" it will need a complete rewire. BUT new cables can be added in the new colours so long as a sticker to that effect is placed on the CU.

So long as the total floor area is less than 100m 2 you can have as many sockets as you like.

it is how ever a good idea to have the kitchen on its own ring, because there is the kettle,toaster dish washer w/m which if all on at the same time will draw a lot of current

 

[333rocky333]

Up down, back or front, both ways are used and ok and sometimes one way can be more convenient than the other if one circuit fails.

Anyone working on it should always test and not assume anyway.

As breezer says mixing old and new wiring is ok, providing the existing is up to standard,and this set up now exists in many installations.

I too would reccomend an electrician check it over to see the best way to adapt or replace existing and incorporate all the sockets on the rings, rather than spurs.


Do you have spare fuse ways as you will need one if you proceed.

 

[garethg]

I don't particularly want to touch the consumer unit myself, so I would probably get an electrician in, and get them to check that the rest is up-to-spec' at the same time (I would not be able to confirm this, looking at it, it is the same size as I would use (6mm) and it mostly just looks dusty, not burnt). I was hoping to get some consensus as to how major a task it would be, and it seems that it is quite possible that the work could be done with minor fuss (if I am lucky, only raising carpet and floorboards in the hall and part of 1 room).

Not 100% sure what you mean by 'fuse way', there are two empty slots (blanking plates I would call them) at the end of the consumer unit, and one RCD which is ON (never noticed before), but not labelled on any of the items (not on the unit itself, or the diagram left).

One thing that does concern me slightly, (if you see my other post for the background), I isolated the shower circuit by breaking the RCD, however, there was still a 5.9V induced AC voltage on the live (and 3V on the neutral). One of these touched the earth, and the current was enough to trip the consumer box RCD.
Thanks!

 

[333rocky333]

A fuseway is somewhere to fit another fuse or mcb, if spare they may have been fitted with a blank way.

The sockets are more likely 2.5mm rather than 6mm though.

The main rcd does sometimes trip when you touch the neutral to earth, even with the circuit MCB off, that is quite normal.