Weird wiring.

[Dave Plowman (News)]

A mate asked me to help sort out a couple of leaks in his toilet, and a dribbling overflow from the main header tank. But that's not the main story. As there was no lighting in the roof void where the tank is so I said I'd fit some.

The house is a 25 year old Barratt's timber framed type. With weird wiring. The lighting is wired in singles - 1mm grey double sheathed cable with a red or black inner. Earth just ordinary green/yellow. All just draped across the joists for the shortest run. The lines looped to the next in the switch box - and the neutrals looped to the next in the ceiling rose. The earth seemed to run at random - but was looped at every switch or ceiling rose I looked at.

I've never seen this before. Always either JBs or ceiling roses used for the required connections. Any guesses as to why it was done this way? Quite wasteful of cable, I'd have said. As most switches had two line runs as it were, one switch return and two earth runs.

Would this really have either saved money in materials or time over 'conventional' in TW&E? Saving money was very important judging by the build of the rest of the house. ;-)

[js.b1]

Unless the cable was free, or from some other job being used up. With Barratt... you're lucky it is not an open back film-set :-)

[ARWadsworth]

Somebody used the wrong cable and had to put the earth in later? ie they should have used red singles with an earth not just red singles.

Adam

[Dave Plowman (News)]

They used grey covered red singles for all the lines and switch returns. Gray covered black for the neutrals. So nothing wrong there. But makes identifying what does what more difficult as they all look the same on the outside. ;-)

[RubberBiker]

Simple explanation - chap had run out of correct wiring, had to get the job done - used what he had in the van. Didn't even bother about earths.

Sometime later, wiring inspection failed, someone else adds in earths.

[Bob Minchin]

There was a period, 70s I think when cable was in short supply and various strange cable types got used. I removed quite a lot of copper 'plated' aluminium t&e when re-building my house in the early 80s.

Bob

[TheScullster]

"Dave Plowman (News)" wrote

I have a 1970s build property, part of a small(ish) estate west of Hull. The lighting is wired similarly, but the earth is catered for by the use of singles&earth. Enough of the individual line and neutral cables have integral earth to ensure all switch and ceiling rose points are earthed - fortunately. Takes a bit of sussing when you're used to the modern twin&earth loop-in standard. Can also be even-more-confusing when some pratt has used black singles for line duty (this was later work not original install).

Phil

[Dave Plowman (News)]

Since it is an estate, I doubt it.

Earths look like they were installed at the same time.

[Dave Plowman (News)]

A single cable with an ECC? Never seen that one.

Plenty older houses were wired in singles - but before TW&E became the norm. And this house was built long after that was the case - and long after earthed lighting circuits too. As it happens it's quite convenient in some ways - makes installing a different light fitting somewhat easier since there's no loop in loop out ceiling rose to worry about.

[js.b1]

1-core...

- 6181Y - Grey sheath over red/black insulation.

- 6181YH - Grey sheath over brown/blue insulation.

1-core + CPC...

- 6241Y - Grey sheath over red insulation & bare CPC.

- 6241YH - Grey sheath over brown insulation & bare CPC.

- Obviously black/blue equally used.

6181Y often used with the various "pilot wire" heater systems (Dimplex, Creda, probably Consort too). I think 6241Y might be replacing it because the CPC helps trip the RCD side rather than rely on OC protection, or because it is a bit more mechanically robust (1.0mm is really wimpy).

[Dave Plowman (News)]

You live and learn. ;-)