Rewire needed?

[Couleddie]

Was talking to a friend last night about the wiring in her 1930s mid terrace. She recently had some new kitchen lights fitted and the electrician made reference to the rest of the wiring so, knowing I have a keen interest in wiring and am currently attempting to make my knowledge official, she asked my opinion. Not having yet had a chance to have a look i'm limited at the moment as to how much info I have but I wanted to get some opinions on what i'm looking at.

What I know so far is that the sockets are the skirting surface mounted beige toggle-switched MKs. Not sure when these were last used but i'm guessing early 60s. What is the likelihood of the wiring NOT being PVC? The CU has not been upgraded and i'm guessing the lighting circuits have no earth.

My grandparents lived in a similar house (since new) which had the sockets rewired (replacing round pin) in 1978 (my granddad was a sparky) but when I investigated the lights back in 1999 they were still rubber sheathed but the accessories had bene replaced. I'm thinking this could be what i'll find in my friend's house as I know a lot of 1930s properties had the round pin sockets updated to 13amp in the 50s and 60s but the lighting circuits were not replaced.

Another question - what CU. I know split load is now considered old hat but I hear a lot of talk about dual RCD. I always assumed lighting circuits shouldn't be RCD protected but don't circuits with cables buried less than 50mm in walls need RCD protection. Not sure yet but there is a possibility that the original conduit is still present in the lighting circuits.

I'm trying to get a look sometime this week really to ascertain if anything needs urgent attention and what the next steps are.

I'm intending to tackle this job myself in accordance with Part P and all the other relevant paper shuffling. I said she could wait until next year when i've (hopefully) become 'official' but I think it needs a look now.

Any thoughts (i'm sure there will be some) would be very much appreciated.

 

[Andy™]

i think at 1930's wiring itll definatly need re-wiring, and most likely, the sooner the better. at a guess id say there is no earth to gas/water (or if there is, probably 2.5 or similar)

cables could be rubber or lead sheath

anything just about all cables in walls need RCD'd, so you lights will probably have to be

dual split load is similar to split load, just has 2 RCD's fed from 1 main switch rather than a main switch and RCD

and as a final note, careful with any fuseholders/flash guards - may be asbestos

 

[sparky999]

When u say become official what are meaning completing C&G or something else?

Have u attended a 17th edition course or intend to do so?

Have you done any work before or is this the first?

If so im sure we can all help you in work and completing ur college course.

 

[Couleddie]

When u say become official what are meaning completing C&G or something else?Have u attended a 17th edition course or intend to do so?

Have you done any work before or is this the first?

If so im sure we can all help you in work and completing ur college course.

Just starting a course that will get me the C&G 2382, 2391 and 2377 as well as Part P and CSCS card. Been seriously into electrical work since 8 years old (29 years ago) and have been 'practicing' for near on 25 years. Unofficially of course but with respect to Part P I am now limited on what I can do and from a personal point of view that's not good. I seriously love doing electrical work and i've done a lot of stuff including rewires, CUs, outside lighting, recessed lighting etc. In fact, most jobs a domestic installer would do. But I need the theory to back up the practical work so here goes.

I'm pretty sure there'll be answers here when I need 'em Pray

 

[kme]

Course there will mate. Good luck

KME

 

[SPECIAL LOCATION]

Hello couleddie.

from the age of the property it does sound as though the wiring will be a bit aged and weary...

you do need to be careful about not disturbing too much in case there is any perishing insulation that just crumbles when you move it!

e.g.

have you got a copy of approved document P..

there is a section in the back there about older wiring practices to be wary of..

such as rubber TRS cables..

http://i291.photobucket.com/albums/ll306/SPECIALLOCATION/OLDRUBBERCABLES.jpg

There is a link on here somewhere to download approved Doc P...

Apache will find it soon I guess?

do you have any test meters?

e.g. an Insulation resistance tester..

in which case you could turn off main switch open the CU,

do an Ins Res test to get an idea of how bad the cables are?

also whilst in the CU look for earth 'CPC' wires on the lighting circuits.

Hope that helps for starters.

Guiness Drink

 

[Andy™]

e.g. an Insulation resistance tester..

maybe even a low reading ohm meter for some installs!

 

[SPECIAL LOCATION]

maybe even a low reading ohm meter for some installs!

yes yes yes....

at the moment I was just thinking about the cables on this instance

e.g if rubber get an idea of how sound they are..

Earth loop & RCD tester also will be a help in general tho ; )B-)

 

[Couleddie]

Thanks all.

Yes, just looking into test meters at the moment. For the moment may look into possibility of hiring as finances are on life support at moment (partner's new car and laptop got there first). Any recommendations would of course be appreciated.

I'm pretty familiar with TRS cable and have experienced the crumbling effect. Was this still used when 13amp installations came in? I've seen a few systems with the skirting mounted sockets wired in pvc with multi-strand conductors but never rubber. I remember the lighting circuits in my terrace were single core rubber with cotton braiding. That was an experience and I kind of got thrown in at the deep end there but somehow I pulled through.

Hopefully going to get a look before the end of the week. May try and get some pictures too.

My course material arrived this evening. Tomorrow the journey begins. I'd like to say I find it daunting but I don't. I think this is where I belong - it's just taken me 20 odd years to admit it. Guiness Drink all round I believe.

 

[SPECIAL LOCATION]

Thanks all. Yes, just looking into test meters at the moment. For the moment may look into possibility of hiring as finances are on life support at moment (partner's new car and laptop got there first). Any recommendations would of course be appreciated.

I'm pretty familiar with TRS cable and have experienced the crumbling effect. Was this still used when 13amp installations came in? I've seen a few systems with the skirting mounted sockets wired in pvc with multi-strand conductors but never rubber. I remember the lighting circuits in my terrace were single core rubber with cotton braiding. That was an experience and I kind of got thrown in at the deep end there but somehow I pulled through.

Hopefully going to get a look before the end of the week. May try and get some pictures too.

My course material arrived this evening. Tomorrow the journey begins. I'd like to say I find it daunting but I don't. I think this is where I belong - it's just taken me 20 odd years to admit it. Guiness Drink all round I believe.

PVC became common place during the 60's

I presume you mean 13amp 3-pin fused square pin type plugs & sockets..

non fused round pin plugs were installed common until early 50's

so yes TRS & 13a plugs .. common!

Have you got Approved document P?

Planning Portal - Approved Document P

download a copy and read Appendix C:

that has a lot of older practice information...

you are fairly limited to what you can do without any testers tho? :|

 

[avinalarf]

and as a final note, careful with any fuseholders/flash guards - may be asbestos

Came across fuseholders for the first time today! How would I know if they were asbestos???

 

[kme]

Awkward question Nat.

if the backing looks like white thick cloth ( bit like a terry nappy with too much starch), its likely to be asbestos.

Hope that helps.

 

[avinalarf]

Awkward question Nat.if the backing looks like white thick cloth ( bit like a terry nappy with too much starch), its likely to be asbestos.

Hope that helps.

I like to be difficult! Thanks KME - the backing is really hard - I was guessing at ceramic - does that sound feasible?

This particular job that i looked at today...the CU was up in a bedroom, tucked away in a corner of a fairly old cottage. Only had my head torch and the owner didn't have one, so light was very poor (will bring power torch when I return!). There were 3 100A main fuses present, but only tails coming from one of them. Why would this be so?

 

[kme]

Maybe conversion from commercial premises - old 3 phase supply?

if its white (ish), and "slightly" spongy, it`ll be asbestos.

Could you post a piccie? please Nat?

Thanks

KME

 

[Apache]

Came across fuseholders for the first time today! How would I know if they were asbestos???

If there's a chance of asbestos you should assume it's there. Decent respirator and try to disturb as little as possible.

From HSE website

Are fully trained to work with asbestos and that you have the right equipment. Are sure what is and is not asbestos, STOP and seek advice if you aren't.

Minimise dust while you work and use hand tools instead of power tools.

Keep materials damp, but not too wet.

Wear a properly fitted, suitable respirator (eg FFP3 type).

Don't smoke, eat or drink in the work area.

Clean up as you go using a special vacuum cleaner (class H), not a brush.

Double bag and label asbestos then dispose of it at an appropriate waste site.

Don't carry asbestos into your car or home. Wear suitable disposable overalls (Type 5) and boots without laces.

Don't take overalls home to wash; they should be disposable and bagged in special asbestos waste bags after use.

Decontaminate yourself after finishing work, wipe down your overalls with a damp rag and remove them before removing your mask.

More info here Asbestos - The hidden killer - Campaign

 

[kme]

Nice link / post / quote `pache.

methinks you could have one of my specials drinkies - plus a "scoob"

Unless you`re on call???????

 

[Apache]

Nice link / post / quote `pache.methinks you could have one of my specials drinkies - plus a "scoob"

Unless you`re on call???????

not on call - a Guinness will do nicely, or however Admin spelt it Guiness Drink

 

[SPECIAL LOCATION]

not on call - a Guinness will do nicely, or however Admin spelt it Guiness Drink

the time to worry is if he spilt it!

 

[avinalarf]

Maybe conversion from commercial premises - old 3 phase supply?if its white (ish), and "slightly" spongy, it`ll be asbestos.

Could you post a piccie? please Nat?

Thanks

KME

Not at all spongy - it was rock hard . Shall take a pic of the whole setup when I go back and attempt to post it.

Cheers all

 

[a1]

If there's a chance of asbestos you should assume it's there. Decent respirator and try to disturb as little as possible. From HSE website

More info here Asbestos - The hidden killer - Campaign

There is an advert on the Radio that encourages you to phone them and they will send you out a free info booklet.

I don't know if it is nationwide, but I should imagine it is.

Quite a hard hitting ad too.