Question for the PH Electricians

[Meeja]

I'm doing a little home improvement (Partitioning off part of my old kitchen to form a utility room)

Currently, there are is only one power socket in that area (which has been spurred from somewhere else!)

I'd like to add four double sockets, and my plan is to run a new 2.5mm ring back to the consumer unit (a really easy cable run, using the loft area of an old kitchen extension, I can get from the proposed utility area to the consumer unit in fifteen feet through the ceiling void)

Breaking into the existing ring that feeds the old kitchen (12 double sockets in total on that ring) is a very tricky cabling job (major floor lifting excercise in the floor-tiled bathroom)

Problem is, back at the consumer unit, there are no spare breaker openings on the RCD side of the split level board.

Is it legal to add a second ring main onto an existing breaker? (ie the breaker that is feeding the currect ring in the old kitchen) - so effectively there will be four live wires into the top of that breaker - two from the existing ring, and two from the new ring?

The way I see it, I can do three things:

1 - add second ring to existing breaker (as described above)
2 - break into exising ring to add sockets
3 - new consumer unit with capacity on the RCD side

Before anyone starts with the Part P stuff, I'm not doing it myself, but am just costing things out to myself at the mo..... breaking into the existing will be labour intensive - hence more cost, and a new consumer unit is obviously going to be more cost.

Not looking to bodge, but just wanted to check whether it is legal and safe.

[Ganglandboss]

You cannot add an extra circuit to a breaker like that - circuits leaving a breaker have to be of similar length and cross sectional area. Either of the other two options are OK.

[Gsw500]

Is there space on the other side of the consumer unit?

Assuming its a split load board...!

If so then you could fit an RCBO mcb/rcd to feed the new ring.

[Meeja]

Gsw500 said:

Is there space on the other side of the consumer unit?

Assuming its a split load board...!

If so then you could fit an RCBO mcb/rcd to feed the new ring.

You mean on the non-RCD side? - Yes

There are six slots on the non-RCD side of the board, and four of them are in use - three for lighting, and one to feed the garage (via an RCD mounted next to the consumer unit)

If I understand that you are saying I can bet a breaker with it's own RCD built in, then that would be a winner..... and presumably fairly cost effective, and easy to fit.

[Meeja]

Ganglandboss said:

You cannot add an extra circuit to a breaker like that - circuits leaving a breaker have to be of similar length and cross sectional area. Either of the other two options are OK.

Thanks - that's the cheapest option out of the window then.....

Bugger.

[mik.ross]

Why not break into the existing ring main at the consumer unit instead of at a socket.

[Gsw500]

Meeja said:

You mean on the non-RCD side? - Yes

If I understand that you are saying I can bet a breaker with it's own RCD built in, then that would be a winner..... and presumably fairly cost effective, and easy to fit.

Easy to fit... Yes. As an mcb.

Should cost you around £30

[Meeja]

mik.ross said:

Why not break into the existing ring main at the consumer unit instead of at a socket.

The consumer unit is position just under the ceiling in my downstairs loo. The cables go out of the back of the unit, into the underfloor area of the bathroom.

The new ring cables will come down from the ceiling above the unit

Unless it is safe to make connections to cables within the consumer unit itself, there wouldn't be enough slack on either of the legs of the existing ring to take the cable up into the ceiling void and connect to the new cables (if that makes sense)

Also don't know if there is a max allowed number of sockets on a 2.5mm ring?