New extension

[Tipi]

My neighbours are having a small new extension built in the new year and have asked me to do the electrics for them.

They have a 6 way Wylex board in the garage probably 40 years old.

The majority of the cables are ancient (stranded conductors PVC insulation). There have been some alterations done professionally in the last 10 years or so.

They don't want a rewire (and I certainly wouldn't want to take it on).

So, what's my best option?

Install a second CU just for light and power to the new or extend the existing installation?

From what I've seen the installation probably conforms to 15th Ed

 

[betty swollocks]

if it was me,

i'd split the tails and install a new db to serve the new circuits for the extension upgrading the bonding if required

that way theres no need to concern yourself with the existing wiring

 

[danny7299]

if it was me,i'd split the tails and install a new db to serve the new circuits for the extension upgrading the bonding if required

that way theres no need to concern yourself with the existing wiring

+1

 

[Evans Electric]

You have two options , Betty's way as above or replace the C/U ,. Nothing wrong with Betty's method ,I do it a lot, but really its time that Wylex went , I assume its rewirable.

There should be no problem with the age of their "ancient" "stranded" cable , nothing wrong with 15th edition wiring ( been OK for 40 years has it not?)

So I think you should advise a board upgrade , then at least they will have RCD protection for their outside plugs and shower .

 

[Larnacaman]

There should be no problem with the age of their "ancient" "stranded" cable , nothing wrong with 15th edition wiring ( been OK for 40 years has it not?) So I think you should advise a board upgrade , then at least they will have RCD protection for their outside plugs and shower .

Agree 100% ....Sound advise!!

 

[Manator]

There should be no problem with the age of their "ancient" "stranded" cable , nothing wrong with 15th edition wiring ( been OK for 40 years has it not?)

So I think you should advise a board upgrade , then at least they will have RCD protection for their outside plugs and shower .

Subject to testing I would assume nothing.

 

[Tipi]

Thanks all,

You're quite right: it's a rewireable Wylex board. Ugh. No sign of any catastrophic faults though.

I'll test the existing installation.

The electric shower was removed when the bathroom was redone a few years ago - it has electric underfloor heating and a power shower run from a sub CU in the airing cupboard (30mA RCD). Looks like the shower circuit got reused. No sign of a cpc other than that in the 6mm2 T&E. Is one required when RCD installed?

They have no outdoor sockets though I guess the electric chain-saw gets used outside

No cpc on the existing lighting circuits of course.

Replacing the CU looks like the best option if the rest of the installation checks out. Otherwise I'll just split the tails...

 

[batty]

Amazing they can afford an extension but not rewire there lighting.

 

[Tipi]

Yes, perhaps if they hadn't redecorated they might consider a rewire. But then, if I hadn't just put a new set of tyres on the car I'd have got rid when the fuel pump failed...

 

[SLIPSHOD & SLAPDASH]

You may be opening a can of worms replacing the C/U when there is no Cpc in the lighting

 

[SPECIAL LOCATION]

My neighbours are having a small new extension built in the new year and have asked me to do the electrics for them.They have a 6 way Wylex board in the garage probably 40 years old.

The majority of the cables are ancient (stranded conductors PVC insulation). There have been some alterations done professionally in the last 10 years or so.They don't want a rewire (and I certainly wouldn't want to take it on).

So, what's my best option?

Install a second CU just for light and power to the new or extend the existing installation?

From what I've seen the installation probably conforms to 15th Ed

The FIRST question HAS to be...

When was the whole installation last inspected & tested?

or is there NO sticker on the board telling you? as per 514.12.1 page 93 Big red book.

Or can they give you copies of the previous electrical certificates as per 15th?

As significant alterations & additions are going to to added to the installation I would be recommending a FULL PIR to asses the condition, arrangement & loading of the existing circuits.

Without knowing exactly whats there..

It is impossible to say whether it is better to add NEW circuits or extend existing.

e.g. a few more lights may well fit comfortably onto the existing circuit...

Or the existing lights may be easily split into a more pratical arrangement?

With some bargain prices available for some fully loaded Dual RCD CU's

It may well be just as cheap to put a complete new CU on the wall..

As it is ONLY 6 circuits.. allowing 1/2 hr per circuit to test and swap onto new board,

3hours extra would be a negligible cost figure relative to new circuits and building works.. and IMHO give a far more satisfactory overall result rather than leaving an OLD CU that will STILL need replacing at some future date....

What happens if while you are working there they say..

can you put one extra socket in the bedroom or that new outside light or extractor fan in the downstairs loo...

You then got to start looking at making existing circuits comply which can be a ****** if you are still running off the Wylex!!!

Bit of basic common sense, good practice & overall value for money needs to be applied IMHO...

:coffee

 

[Tipi]

You may be opening a can of worms replacing the C/U when there is no Cpc in the lighting

Indeed. On further examination there is a cpc to all the ceiling roses, none at the plateswitches though. The boxes have no terminal to connect a cpc and so my guess is it was cut off.

---------- AUTO MERGE Post added at 20:29 ---------- Previous post was at 19:46 ----------

The FIRST question HAS to be...When was the whole installation last inspected & tested?

or is there NO sticker on the board telling you? as per 514.12.1 page 93 Big red book.

You're having a laugh.

They have lived there for over 25 years. It will never have had a full inspection and test. The bathroom and kitchen were both done before Part P.

Or can they give you copies of the previous electrical certificates as per 15th?

See above

As significant alterations & additions are going to to added to the installation I would be recommending a FULL PIR to asses the condition, arrangement & loading of the existing circuits.

It still depends on the state of the existing. If it's unsafe I wouldn't be going ahead without rectifying any problems. If it merely doesn't comply with 17th then splitting the tails looks like the better option.

Without knowing exactly whats there..

It is impossible to say whether it is better to add NEW circuits or extend existing.

e.g. a few more lights may well fit comfortably onto the existing circuit...

Or the existing lights may be easily split into a more pratical arrangement?

One circuit for upstairs lights, one for downstairs. Only 8 points downstairs - only require another two - no problem there (apart from that missing cpc)

and a couple of extra socket outlets.

With some bargain prices available for some fully loaded Dual RCD CU's

It may well be just as cheap to put a complete new CU on the wall..

As it is ONLY 6 circuits.. allowing 1/2 hr per circuit to test and swap onto new board, 3 hours extra would be a negligible cost figure relative to new circuits and building works.. and IMHO give a far more satisfactory overall result rather than leaving an OLD CU that will STILL need replacing at some future date....

That's a very good point.