New ring main in kitchen

[Barry]

Traditionally / historically (to me, at least) it seems that cable drops to sockets and switches are just that, ie, vertical drops from ceiling to socket. My question is, is it possible to run cable horizontally and still comply with the various rules and regs?

Forget Part P and kitchens for now (that will be dealt with properly), I just want to know if my plan is feasible as it would make life so much easier.

We're renovating our kitchen and I want to rewire and give it it's own ring main before plastering and tiling. If I stand looking at my kitchen window, there is a wall to my right and behind this particular part of it is the glory hole "under the stairs", on which is mounted the consumer unit, at a height of about 2ft 4in maybe 2ft 5in.

What I'd like to do is to go under the stairs, drill out through the back of the consumer unit and then chase a channel out horizontally, at that height, around that wall, then going vertically up to socket boxes positioned on that wall above the worktops, finally going up and across the ceiling void to drop down to sockets on the opposite wall. I'm an absolutely abysmal drawer but, if you promise not to laugh too much, you can see a very rough drawing of what I mean here:

for your input, good or bad.

Barry

[Christian McArdle]

In a kitchen, I would run horizontally directly from socket to socket at the above worktop height. This reduces the circuit length. It is allowed by regulations, although I would only consider it in the kitchen situation.

Your solution is only acceptable if the horizontal sections are surface mounted on the wall (i.e. behind the units). If buried, then they would need physical protection.

Christian.

[David Hansen]

On Mon, 17 Jul 2006 15:55:20 +0100 someone who may be "Barry" wrote this:-

That would be fine if:-

1) all the cable runs are mechanically protected under the surface.

2) the cable is run on the surface.

3) the cable is run horizontally or vertically between visible sockets, with or without mechanical protection. You could drill above the consumer unit to come out into the back of a socket and then run horizontally to the next socket.

From a socket as 3), otherwise 1) or 2).

No problem.

As in my first paragraph.

[Barry]

Thanks for your reply Christian. If you'd be so kind to have a look at my (equally abysmal) second drawing here:

would that be the preferable option. I hadn't thought about a socket on the dividing wall between kitchen and "under the stairs" but it would certainly come in handy.

Thanks,

Barry

[Ron Lowe]

And you will run a second 2.5 T+E in the same channel, from the last socket all the way back to the CU to complete the ring?

Or will you run the other leg of the ring a different route back to the CU?

[Barry]

A different route back Ron. The layout in my useless illustrations is because the bath is above that particular part of the kitchen and the side of the bath has been tiled over by the previous occupant of the house. It looks lovely but there's no obvious way of getting the side of the bath off without smashing the tiles - hence I can only go up into the ceiling void once I'm past the bath :o)

Barry.

[Dave Plowman (News)]

- not down, horizontal, then up as shown. This is pretty convenient as you'll usually be covering the cable run with tiles so it doesn't have to be made good to perfection. It's also worth not actually fixing the backing boxes until you tile - as it's then possible to get them exactly uniform between tiles and coarses.

At the first and last socket if you wish to run horizontal from that you'll need to protect the cable - only vertical is acceptable unprotected.

[Guy King]

The message from David Hansen contains these words:

What qualifies as protection?

[Tim S]

Heavy gauge steel conduit (not the thin stuff). I believe standard capping, metal or plastic doesn't count.

Or, some types of cable are deemed to be inherently protected, eg MICC, SWA or earthed-foil screened cable of a certain BS type (can look up if you are interested).

HTH

Tim

[Barry]

Thanks very much one and all, I'm a much happier bunny now :o)

Barry.

[Christian McArdle]

Looks fine to me. Be careful not to unbalance the ring using a long unsocketed run back to the consumer unit.

In fact, with the layout as proposed, it is essential if you want to avoid the need for cable protection.

Christian.

[Dave Plowman (News)]

Not sure about that one - it might well happen that most of the load on a ring is taken off 'one end' only in practice? Doesn't the design allow for this?

[Christian McArdle]

When designing such circuits, I tend to run the flow and return (as it were) alongside each other. However, I alternate which cable gets each socket. This way, balance is usually maintained, even if much of the load tends to one geographic location.

If you anticipate all the heavy load at one end, you should make allowances in the design. Either use 4mm cable, a radial circuit, or the method above.

Christian.

[Fred]

This may sound a daft question but is there any requirement in the regulations to balance a circuit?

If it was deemed important wouldn't it have been added? The regulation already assume a maximum working temperature of 70 degs C for PVC covered wire where in practice an occasional working temperature over this is not going to do much harm. In terms of temperature do the regulations take into account of things like heat above light fittings?