Buying a new house - scared of rewire - please advise

[gunnersellit]

Hi all
The wife and I are buying a new family home. Price agreed but since then we have looked again and I have scared myself a little when thinking about electrics. Its a 1930's house and I went round to take another look.

We've paid for a homebuyers survey but understand they wont really check the electrics.

There was a double floor extension in 1986 so that part of the property seems ok (not perfect I know, but must be more modern than the rest I think).

I took some pics of the fuse box, its the same as the one in my inlaws house but they have little trip switches in place of the current fuses.

The plug sockets are all modern - not round pins anyway - we opened two and they had earths.

The light switches are all the bakerlite style apart from the extension and they dont seem to have earth wires in the switch or the fitting. The hallway pendants and others look old, with the wire twisted from the rose down to the light. The dining room however has 4 wall lights (all metal) and a ceiling light (again metal). We did not remove these to have a look, but surely they should have an earth!

I know I have not given too much info, but hope to get myself an action plan for the purchase. Are we facing a rewire, or could we upgrade things? what questions do I ask, and can I push the surveyor to doing any more than normal.

Thank
Paul

Untitled

• gunnersellit
• 2 Mar 2011
• 1

Untitled

• gunnersellit
• 2 Mar 2011
• 1

 

[RF Lighting]

I'm sure you'll appreciate it's hard to say without actually seeing the job, but given the age of the fuse box, and your description of the installation I would have said that a rewire is most likely going to be required.

With the fact you are about to move in then now is absoloutly the time to have the house rewired.

 

[ban-all-sheds]

We've paid for a homebuyers survey but understand they wont really check the electrics.

Your understanding is correct.

There was a double floor extension in 1986 so that part of the property seems ok (not perfect I know, but must be more modern than the rest I think).

It could still be no good, though. There's more than on cowboy electrician relaxing at home right now having done dodgy work today.

The plug sockets are all modern - not round pins anyway - we opened two and they had earths.

Did you notice what type of insulation the cables had?

The light switches are all the bakerlite style apart from the extension and they dont seem to have earth wires in the switch or the fitting.

That probably makes the wiring at least 45 years old.

The dining room however has 4 wall lights (all metal) and a ceiling light (again metal). We did not remove these to have a look, but surely they should have an earth!

They should, and they might - you need to check (with the power off). Buy some plastic switches first though so that you can swap them there and then if you find there is no earth.

Are we facing a rewire, or could we upgrade things?

Impossible for anyone here to say, but you should assume the worst if you've got budgets to set, or if you can revise your offer.

what questions do I ask, and can I push the surveyor to doing any more than normal.

You could, but even if he did more than normal, and even if what he did was any use, you'd be be paying surveyors' rates for it, so you don't want to do that.

You need a electrician to carry out a Periodic Inspection.

Will you be moving in straight away? If you do have it rewired it will cost less (because it will take less time) if the house is unoccupied and empty of furniture.

 

[oharaf]

Must say from your description, and with out a Periodic Inspection is hard to say. However there are tell tale signs there. Bite the bullet get in done by someone here

www.competentperson.co.uk

then you're good to go for 30 years

 

[kai]

That service fuse holder - the black box to the right of the meter - looks upside down - is that a TT supply you have there? - the main earth appears to not link up to the neutral section of the service fuse holder as is the case nowadays.

 

[gunnersellit]

Hi
Thanks so far, I have no ides what a tt supply is? I would have thought that earth cable from the box would go off to an earth, not into the black holder?

But I really have no idea? Is the presence of that earth cable unexpected then? Would it have been installed at a later date to the main board?

 

[kai]

In most modern installations (indeed even in my old 1968 built terraced house) the main earth goes into the Neutral part of the Service Fuse Unit - in the form of a PME or TNCS earthing, where the incoming neutral acts as both the earth and neutral conductors from the sub-station.

If you have a TT earth, it means that you rely on an earth stake or rod to provide the earth (as opposed to an electricity company earth), so special precautions can be required on TT supplies.

If you have a TNS supply, i.e. where the main earth is soldered onto the metallic armouring of the supply cable (usually on older installations), that is another form of earthing.

 

[iCraig]

Hi,

As someone thats just had a rewire, I'd either go with a PIR and see what comes back and then rectify it.
Or do what I did, think long term and just bite the bullet and rewire.

I am so glad I did the latter, as when the rewire was in progress although 60% of the wires were PVC, 40% were rubber and some were in shocking condition. And all the DIY bodges over the years were shocking too.

Now after having had it done, we now have sockets where we want them, the lights we want and the piece of mind of having had it done and no need to worry about it for atleast the next 30 years! And I went for an NICEIC approved contractor so got abit of back up from that too.

Cheers

Craig

 

[ban-all-sheds]

the main earth appears to not link up to the neutral section of the service fuse holder as is the case nowadays.

1) Why does that make you laugh so much?

2) How do you know what is, or is not happening, shortly after the point where both the earth cable and the supply cable disappear from view, close together?

 

[ajrobb]

Because the earth doesn't go to the main fuse, it might be a TT supply rather than TN-C-S or TN-S supply. A TT supply has to be used if the neutral cannot carry sufficient fault current back to the distribution transformer's earth. A modern TT installation might use a local earth and would be protected by a 100mA RCD in place of the mains isolator (because the local earth also cannot carry the full fault current).

It is now required that most PVC cable should be protected by 30mA or 100mA RCD on re-wires and new installations (in case someone drives a nail through a cable). Also socket and bathroom circuits should have 30mA RCDs to protect inhabitants from lethal shocks.

If you pay for a Periodic Inspection Report (PIR), you'll KNOW what needs fixing and can get quotes. This can be used as a bargaining tool to get a discount on the house.

 

[ban-all-sheds]

Hi
Thanks so far, I have no ides what a tt supply is? I would have thought that earth cable from the box would go off to an earth, not into the black holder?

But I really have no idea? Is the presence of that earth cable unexpected then? Would it have been installed at a later date to the main board?

//www.diynot.com/wiki/electrics:earthing-arrangements

 

[aptsys]

A TT supply has to be used if the neutral cannot carry sufficient fault current back to the distribution transformer's earth.

AND if there are not multiple rods along the supply cable

 

[ban-all-sheds]

OR if there are not multiple rods along the supply cable....

Not that any DNO would offer a TN-C-S supply without PME.

 

[securespark]

I would hazard a guess it is overhead TT.

The earthing conductor appears to follow the same route as the incoming supply cable.

It is crucial you have a PIR.