Lighting circuit without earth - mounting flush posible?!

[AndyPRK]

At the time, the light switches would have had metal back boxes, however where the screw threads go into would have been nylon (or some insulator).
I don't know if you can still get these though.....

 

[bernardgreen]

Eniacs wrote

It may have been regs for a few years, but the house was built in 1959. Im not going to upgrade the house every single time a new reg comes out.

You don't have to and no one is pressuring you to do that.

Its been SAFE and WORKED for 50 years now, its not going to change in the future.

It has worked for 50 years now and now one has had an accident with it. That does not mean it is safe and and accident will not happen in the future.

It will change as the insulation deteriorates and copper corrodes and all manner of other things age.

You are changing the switches, so you are disturbing the cables. If the insulation has become brittle it may just fail.

Would you drive your loved ones on the motorway in a fifty year old car without having had the brakes and steering checked for wear and tear and deterioration from rust ?

 

[eniacs]

Hi Bernard;

Your right - if the insulation comes off i will have to replace it. It is in good condition in the ones i looked at - i was amazed when i realised it was from 1959 - it doesnt look at all like it, i would have put it at 1990 myself.

Tradingdepot has a number of surface and embedded PVC boxes i'll use one of those. Thanks to the genuine replys to this post.

 

[flameport]

It may have been regs for a few years, but the house was built in 1959. Im not going to upgrade the house every single time a new reg comes out.

Upgrading every time the regulations are updated is not required.
However when your house was built, the wiring regulations were the 13th edition. The current edition is the 17th.
Those are just the major editions, and doesn't include the 30+ amendments which have been published during the last 50 years.

Its been SAFE and WORKED for 50 years now, its not going to change in the future.

Safe and working are two very different things, and any wiring 50 years old is life expired, regardless of how well it was installed originally.

I'll go with the standard PVC box in the wall i think. I have 3 weeks to complete the house not 3 months!

Replacing the lighting wiring in a typical house would take a week at most, and in many cases only a few days.

 

[RF Lighting]

There is no point wasting your breath with this fellar.

I don't even understand why he came here, if all he's going to do is ignore our advice, and just carry on with his original plan anyway.

 

[eniacs]

FYI im on a high voltage course as we speak i normally deal with 11'000volts so im well aware of what is safe and what is not.

Im a marine electrician and qualified to degree level. I do maintenance on my car too so its not like im a newbie to safety or electrics or doing any kind of DIY...

 

[Johnmelad502]

The house might be 50 years old but the wiring might only be a few tears old.

Anyway, have a look here and you might find what you need to allow the use of metal back boxes.
http://shop.comdir.co.uk/Products.aspx?intGroupID=968

 

[RF Lighting]

FYI im on a high voltage course as we speak i normally deal with 11'000volts so im well aware of what is safe and what is not.

Im a marine electrician and qualified to degree level. I do maintenance on my car too so its not like im a newbie to safety or electrics or doing any kind of DIY...

Woopie do for you

 

[bernardgreen]

If the insulation crumbles even just slightly at the switch then it is porous.

Condensation or other water getting to the cable in the wall or ceiling will penetrate the insulation. This will corrode the copper making it thinner and this might then lead to the copper overheating and starting a fire.

Or the damp will conduct electricity to the surface and provide a nice at best tingly area on the wall. Or maybe a area of with fatal potential.

If are plastering the walls in the area where there may be old cables take care with the wet plaster and the metal trowel.

 

[eniacs]

Alrite John;

Nice solution - thinking outside the box i like it!

RF lighting;

Thanks for the usefull replies! Why did you bother posting here!

Flameport;

Its not running the wires that would take me the time - and i'd enjoy that - its the telling the authorities, and then the repairs work afterwards that i couldnt get done quickly

 

[flameport]

The house might be 50 years old but the wiring might only be a few tears old.

The wiring has no earth, which means it will be 1966 at the latest. 43 years ago.
Even allowing for someone using old stock of cables and not using the current (at the time) wiring regulations, it will be at least 40 years old.

 

[flameport]

its the telling the authorities, and then the repairs work afterwards that i couldnt get done quickly

10 minutes to fill in and post a building notice, and a couple of hours filling in the chases above the light switches?

 

[sparkwright]

1959?
i assume your old wiring is PVC?
it's not rubber is it?

 

[RF Lighting]

RF lighting;

Thanks for the usefull replies! Why did you bother posting here!

Because I like to help people carry out safe electrical installations.

When someone is just going to bludgeon on regardless of what everyone is telling them then WTF is the point of me even trying?

 

[eniacs]

Sparkwright;

Yes its PVC - if it was rubber i'd be rewiring!!!

Flameport;

I was worried about the ceilings in the ground floor - i'd have to rip down the ceiling or pull up the floors and every single light in the house is a wall mount light (apart from kitchen and bathroom thinking about it)

The house was built 1959 since the regs change was 1966 the wiring must be original...