Lighting Junction Box Advice

[Mushty]

We have lived in a 1930s home for several years now that has a loft conversion. I've just been out in the roof space around the room in the loft and have found a junction box that serves a bedroom light in a room below containing the cable in and out and to the light and switch. All four have the earth wire just snipped off, is this something old sparks would do, I'm thinking not, of course.

So it's been like this for all the time we've been here and for however many years before. I've found another nearby with the earths twisted together outside the JB which I believe isn't uncommon but I think not done these days. It's certainly left me wondering what other potentially iffy electrics are hidden under the floor!

Any advice greatly appreciated.

 

[Murdochcat]

There are lots of installs like this and it’sa really good idea to make improvements. That said unless you have some test kit you won’t be able to confirm earth continuity

 

[Mushty]

Thanks for the prompt reply - so are you saying it's not necessarily dangerous?

 

[plugwash]

We have lived in a 1930s home for several years now that has a loft conversion. I've just been out in the roof space around the room in the loft and have found a junction box that serves a bedroom light in a room below containing the cable in and out and to the light and switch. All four have the earth wire just snipped off, is this something old sparks would do,

Maybe some would have done it when earths first came in, old habbits die hard and all that, but earths have been required for decades now.

So it's been like this for all the time we've been here and for however many years before.

The presense of brown/blue cable tells us that it was done in 2004 or later.

Thanks for the prompt reply - so are you saying it's not necessarily dangerous?

It depends what's fed from the circuit past the point of the "breaks".

If there are metal light fittings then it would be classed as "potentially dangerous" on a condition report, but the danger is frankly pretty low, since light fittings are touched rarely and even more rarely touched at the same time as anything else.

If there are metal lightswitches past the point of the break the risk is rather higher.

 

[robinbanks]

All four have the earth wire just snipped off

It may be that the lighting circuit pictured here joins into or is fed from a section of the circuit that has no earths; not uncommon for old lighting installs to be earthless. Snipping the wires thus does strongly indicate that this part of the lighting circuit has no earthing arrangement. You should proceed appropriately and install only light fittings that are double insulated (look for a square inside a square on the outside of the box) and light switches that are not metal (hello boring white plastic!)

If you can successfully trace an earth path from the consumer unit to here then link them up by all means but I rather get the impression that you won't succeed (and don't just open the CU, see a 2core+earth leaving the lighting MCB and assume it means the whole lighting circuit is successfully earthed; test and make sure, and test for full earth continuity after you do any linking

Personally, as you may not have appropriate test gear, I feel it safer to assume your lighting circuithas no earthing anywhere and install accessories that you touch as appropriate, infuriating as it may be to find something you like the look of, at a price you want to pay, that is double insulated

If there are metal light fittings then it would be classed as "potentially dangerous" on a condition report, but the danger is frankly pretty low

Picking up a C2 for it would stop you being able to rent the property out, if that steers your opinion - you're allowed to live with the danger yourself but not kill a tenant with it. If you treat your own life as if equal worth to a tenant, you may want to attend to C2s

 

[Mushty]

Thanks for the replies, that's a bit more reassuring. I'm planning on investigating a bit more when I get the chance just to see what else I can safely see around. The place has clearly been rewired at some point, there is evidence of old discarded black rubber cable where it has been replaced, it's mostIy white pvc (red/black) but assume additional work was probably done when the loft conversion took place, hence the (post 2004) grey (blue/brown).

The CU has probably been around for a while, it's a plastic Square D Quickline II and there is also another small CU in the loft conversion that would have been added at the time - probably time to get it all checked over by a qualified spark.

Cheers.

 

[blup]

An up to date board with rcd/rcbo’s provides an additional measure of safety for faulty earth wiring but does not address the problem as there are likely to be metal switches and back boxes in the circuit. Testing earth continuity would identify if the problem is limited to that jb.