Green goo

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Has anybody out there experienced the, I believe, traumatic experience of a full house rewire caused by the appearance of green goo? Over the years I have cleaned some sockets contaminated with the green stuff. Should I consider a rewire even if only some sockets and one or two switches are affected? Our house in West Yorkshire was built in 1969. Thanks in advance for your comments.
 
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The cables affected need to be replaced. This generally means all of them, as they would have all been installed at the same time originally.
If some have already been replaced or installed more recently, they may not require replacement.

You can clean the gunge away for as long as you like - it will return and the underlying problem will still be there.

The gunge is the result of a chemical reaction between the plasticiser in the insulation and the copper wire. It can be insulating or conductive, depending on how much copper has reacted with it. This will cause faults where things such as switches cease working, or in other cases conductive paths between wires which will result in overheating and short circuits, blown fuses and so on. Eventually the cable insulation becomes brittle, cracks and leaves exposed wires.

Like it or not, the only solution is to replace the affected cables. How disruptive that is depends on how and where the cables were originally installed.
If in conduit, it may be possible to pull new ones in with little or no disruption. If directly plastered in the walls, then damage, replastering and redecorating is inevitable, unless you want surface mounted cables.
 
The cables affected need to be replaced. This generally means all of them, as they would have all been installed at the same time originally.
If some have already been replaced or installed more recently, they may not require replacement.

You can clean the gunge away for as long as you like - it will return and the underlying problem will still be there.

The gunge is the result of a chemical reaction between the plasticiser in the insulation and the copper wire. It can be insulating or conductive, depending on how much copper has reacted with it. This will cause faults where things such as switches cease working, or in other cases conductive paths between wires which will result in overheating and short circuits, blown fuses and so on. Eventually the cable insulation becomes brittle, cracks and leaves exposed wires.

Like it or not, the only solution is to replace the affected cables. How disruptive that is depends on how and where the cables were originally installed.
If in conduit, it may be possible to pull new ones in with little or no disruption. If directly plastered in the walls, then damage, replastering and redecorating is inevitable, unless you want surface mounted cables.
Thanks for your comments flameport. I'll bear in mind what you have just told me.
 
It seems Woolworths in Australia had bought a load of cable from China and are being required to foot the bill for house re-wires as a result. some reports talk about fire risk others say although the cable will become brittle since used with fixed installations it should not be a problem.

Most manufacturers have been through the problem and it's now rare, but it seems Infinity and Olsent brand were unaware of the problems and so did not test the cable before importing a huge quantity. I have never heard of any firm being required to re-wire a house because of this fault in the UK. Although if the firm is still trading I suppose it could happen.
 
It seems Woolworths in Australia had bought a load of cable from China and are being required to foot the bill for house re-wires as a result. some reports talk about fire risk others say although the cable will become brittle since used with fixed installations it should not be a problem.

Most manufacturers have been through the problem and it's now rare, but it seems Infinity and Olsent brand were unaware of the problems and so did not test the cable before importing a huge quantity. I have never heard of any firm being required to re-wire a house because of this fault in the UK. Although if the firm is still trading I suppose it could happen.
My post is about green goo affecting cables installed in the 60s.
 
It seems Woolworths in Australia had bought a load of cable from China and are being required to foot the bill for house re-wires as a result. some reports talk about fire risk others say although the cable will become brittle since used with fixed installations it should not be a problem.

Most manufacturers have been through the problem and it's now rare, but it seems Infinity and Olsent brand were unaware of the problems and so did not test the cable before importing a huge quantity. I have never heard of any firm being required to re-wire a house because of this fault in the UK. Although if the firm is still trading I suppose it could happen.
The Infinity and Olsent cables are a different problem. See https://www.accc.gov.au/update/infinity-cable-recall-act-now-before-its-too-late, among others)

The Green Goo problem is referenced in
https://www.toms-electrical-services.co.uk/green-goo-wiring/
http://www.electriciansforums.co.uk/threads/green-residue.20323/
an many others.
 
From what I have read both the Infinity/Olsent cable and the cable found in 60's in some UK homes have the same problem, plasticiser leaching out of the cable. This is made worse in both cases as the cable gets hotter so since Australia has higher temperatures than UK it will be more of a problem there. In the main not only has the plasticiser to have leached out, but also the cable has to have flexed, again brick houses do not flex like ones built from wood, and then the cracks in installation need to allow dust to enter and for that dust to get damp for it to track and heat up, if the wires touch unless very poorly fitted then an overload device should trip, it's when dust builds up and allows tracking so not enough power to trip but enough to heat things up where you have a big problem, again Australia is likely to have more dust than UK.

So because of the country the Australia problem is far higher than UK problem, in the main normal inspection and testing every 10 years will find the problem in the UK before the house goes on fire, but in Australia that is not the case.

However the cable is faulty, there is no question as to if faulty cable or some other external fault, so in theory time does not matter, if a car manufacturer finds a fault in a 10 year old model likely to cause danger they will still do a recall, they will not say Oh it's 10 year old, only designed to last 7 years so we will not recall them. They are dangerous so are recalled. The problem is with a house finding out who made the cable and working out if they are still trading.
 
in the main normal inspection and testing every 10 years will find the problem in the UK before the house goes on fire,

It may be advised but I don't think there is "normal inspection and testing every 10 years" in many UK houses.
 
The green goo is present in some sockets in our house but it doesn't show unless you open up the socket covers. In other words, the contamination, so far, is not severe. I clean the wires about every 3 years. I can't see the need to do a rewire unless it becomes absolutely necessary. Too much of an upheavel.
 
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If the pvc red and black looks sound, its possibly ok, im not sure if its actually conductive, the only real test would be with an INSULATION TESTER to see if the cable core insulation is breaking down, most damage is caused when it runs into the accesories and jams them up, if theres loops behind the accesories then that problems sometimes reduced, i have seen extreme cases where its run out the bottom of a switch and down the wall.
 
I believe the big problem with the slime is that it can get into breakers or switches and gum them up to prevent them operating. A drip loop might help.

There was a paper published by a body (might have been the AEA) responsible for civilian nuclear installations some years ago which I can't find, but here is some info extracted from it.

"This green substance can be either an insulator or a conductor, depending on the chemical reactions involved. Either case can cause serious safety hazards. The substance can drip into components and interfere with their operation. In addition, loss of the plasticizer can lead to embrittlement of the insulation."

https://www.diynot.com/wiki/Electrics:Green-Slime

Here's one I did earlier
34505-190647f01a07a6b65c3c7d987923b194.jpg


[GALLERY=media, 1632]1970's PVC T&E with Green Slime by JohnD posted 3 Jun 2008 at 12:47 PM[/GALLERY]
[GALLERY=media, 1631]1970's PVC T&E with Green Slime by JohnD posted 3 Jun 2008 at 12:47 PM[/GALLERY]

This one was from the 1970's
 
It may be advised but I don't think there is "normal inspection and testing every 10 years" in many UK houses.
It has been debated between my son and I many times, the question should one wire or design with the idea that those who follow may not follow the rules? Be it splitting house side to side instead of up and down, or using light switch back box as a junction box instead of ceiling rose, there is the normal way, and the thoughtful way, which may not be the same, neither breaks the rules, but we have come to expect certain practices.

I feel you can't allow for some one in the future not following the rules or you would simply not wire anything, you have to wire and design with the expectation that those who follow will follow the rules, so people today with lights with no earth should have been made aware of the problem at least five times, within that time they will have redecorated so there is no valid excuse for not modifying, if they have failed to modify then that has been their chose so they can hardly complain that they can't use class I fittings.

So I suppose the question is how long does it take for the green goo to appear? If the cable was fitted in 1970 and the fault became apparent in 1980 then I can see why any supplier or installer would say you have not reported the fault within a reasonable time, so tough you can't claim now, there has to be some time limit, can't really expect the Italians to come and repair Chester's Roman walls. Maybe today it is different but years ago if you got a trade discount then the cost of replacing was down to you, so if you bought an alternator which proves faulty at trade price, then you could return it and get a replacement, but you would not get the labour needed to change it FOC only the alternator.

So if you returned the cable with green goo they may replace the cable, but would not install the cable. And it is not the cost of cable that's the problem, it's the cost of labour to do the work. And cable is considered to have a limit to how long it will last, in the 1950's the rubber cable had quite a short live span, in the 1960's and 70's although the cable was expected to last longer, I don't think anyone expected cable to last 45 years plus, and items like light bulbs have an expected life which is the point where half the bulbs will have failed not when they should all still be working.

At the time when we had cable in the UK which could give out green goo we really did not know that much about plasticiser and how it would act over the years, but the Infinity/Olsent cable was produced when all manufacturers should have known about the problems. So yes the Infinity/Olsent cable was in essence a manufacturer trying it on in the same way as VW did with their cars and emissions. It was a criminal act rather than part of a learning curve.

The question is what to do about the cable? Now if an EICR was done and it failed to find the faulty cable, then there is a case for claiming from person doing EICR. But trying to show that the goo was there when it was inspected would be hard, so in real terms I think unlikely to get anywhere with that, so in real terms it's really down to owner to replace cables. I I had some cables in my dad's old house which were faulty, but it was by no means all cables, however testing to find which cables do need changing and which do not would be hard. Today we should have a paper trail, so cable in living room wall feeding the gas fire ignition system should have paperwork to say it was fitted by Joe Blogs in 1998 connecting into the ring final at upstairs socket directly above the fire. But the active word is should, I have just had a part re-wire, I know what bits they did, but you would have a hard time working out what they did from the paper work. Today I would be able to point out what they did, in 5 years time it would be harder, in 10 years time near impossible. Paperwork says they installed a ring final, but it does not even say how many sockets were on it.

So it would seem you need a re-wire and your going to have to pay, next question is how long will it wait? Near impossible to tell how long before the plasticiser has reduced to point where cables will crack and cause tracking, again looking at dad's old wiring it was to a stage where we could not get a RCD to hold in, so likely with a 30 mA RCD it will trip before it becomes a fire risk, but one can't be sure about that, now if a central heating pipe starts to leak the insurance will not normally pay out, but if it leaks and causes damage they often will, the point between paying for it all and paying for part seems to vary, and maybe insurance will pay out, but if you ask and they say no, then you will have to re-wire immediately so is it really worth asking? All will it just cause more problems.

The big question is:- Is the house habitable with the faults? If you can disconnect the faulty cables then likely yes, if not then for insurance to pay you need some one to stick out their neck and say house not habitable until repairs are completed. And still at mercy of the insurers, seems daft but people with money can take the chance, those without the ready cash have more of a problem.
 
I can't see how house insurers will pay for a rewire. If the house catches fire and insurers could prove the owner knew the wiring was dodgy they may reject the claim. It's not worth the risk IMO.
 
when its bad, it looks like this (one I did earlier!)
[GALLERY=media, 21175]Untitled by Taylortwocities posted 2 Apr 2010 at 9:32 AM[/GALLERY][GALLERY=media, 21177]Untitled by Taylortwocities posted 2 Apr 2010 at 9:32 AM[/GALLERY]
 
when its bad, it looks like this (one I did earlier!)
[GALLERY=media, 21175]Untitled by Taylortwocities posted 2 Apr 2010 at 9:32 AM[/GALLERY][GALLERY=media, 21177]Untitled by Taylortwocities posted 2 Apr 2010 at 9:32 AM[/GALLERY]
Mine definitely doesn't look like that! The main fuse box is immaculate. Some sockets are showing contamination though, on removal of covers. Cleaned them a few years ago and will be keeping an eye on them. Your photos make me feel better. Thanks.
 
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