Estimating the Age of Electrics. Rewiring Fun.

[thedawnbefore]

Hi, I'm about to take leap of faith buying a property which I've not been able to see properly. It has a been extended a couple of times since it was built in 1970 and the current owner has no idea about the history of electrics, no certificates of any kind and doesn't want any visiting electricians. They've not touched it since they moved in 2009.

The consumer unit will need moving to the opposite room at about 20ft.

Pic Attached. Would appreciate an experienced eye guesstimating the age of the board? I'm going to guess 1990's given this was the last extension? We're planning to knock a few walls about and knowing the age of the install might tell me whether I'm likely looking at a complete rewire or just extending the cables!

Any guidance appreciated. Thanks.

 

[James]

I would be putting in my guess at early 90's
but wait, someone will actually know when they made that board, probably within about a 5 year window.

 

[telectrix]

1990's sounds about right. that board could be re-used by replacing the MCBs with RCBOs. can you get a pic with the cover off (isolate at main switch first.).

 

[Pete999]

Hi, I'm about to take leap of faith buying a property which I've not been able to see properly. It has a been extended a couple of times since it was built in 1970 and the current owner has no idea about the history of electrics, no certificates of any kind and doesn't want any visiting electricians. They've not touched it since they moved in 2009.

The consumer unit will need moving to the opposite room at about 20ft.

Pic Attached. Would appreciate an experienced eye guesstimating the age of the board? I'm going to guess 1990's given this was the last extension? We're planning to knock a few walls about and knowing the age of the install might tell me whether I'm likely looking at a complete rewire or just extending the cables!

Any guidance appreciated. Thanks.

Test existing if OK extend the cables and re test, rocket science don't apply. common sense rules OK?

 

[thedawnbefore]

I would be putting in my guess at early 90's
but wait, someone will actually know when they made that board, probably within about a 5 year window.

thanks very much that's helpful!

 

[thedawnbefore]

I would be putting in my guess at early 90's
but wait, someone will actually know when they made that board, probably within about a 5 year window.

1990's sounds about right. that board could be re-used by replacing the MCBs with RCBOs. can you get a pic with the cover off (isolate at main switch first.).

thanks a lot, much appreciated.

 

[thedawnbefore]

Test existing if OK extend the cables and re test, rocket science don't apply. common sense rules OK?

Thanks! All down to test results then. Was wondering if building controls might stipulate new cabling standards or something if the install was beyond a certain age.

 

[loz2754]

So the wiring could be up to 50 years old, regardless of the age of the consumer unit. Indeed a leap of faith!
I wonder why the owner doesn't want any electricians to visit???

 

[thedawnbefore]

So the wiring could be up to 50 years old, regardless of the age of the consumer unit. Indeed a leap of faith!
I wonder why the owner doesn't want any electricians to visit???

Indeed. They are in their mid-70's and covid makes negotiating visitors challenging. Am I nuts? It's a 4 bed, detached with ~10 rooms in total (2 story extension in late '90s) so guessing I'm in for a £5-7k rewire job worst case?

 

[telectrix]

if the cables are all pvc, which was standard in 1970. no reason why it should not last another 50 years if nothing has been abused or butchered.
if you're lucky it could possibly be imperial stranded cable.

 

[thedawnbefore]

if the cables are all pvc, which was standard in 1970. no reason why it should not last another 50 years if nothing has been abused or butchered.
if you're lucky it could possibly be imperial stranded cable.

very helpful, thanks v much..

 

[7029 dave]

I would estimate early 90's for the CU, the wiring could be older, do you know the exact age of the property.

 

[freddo]

As above if the wiring is in good condition and not attacked by poor DIY alteration a rewire may not be needed. However a rewire can be the best option if you want to do a lot of alterations, such as adding extra sockets several rooms, changing a large number of centre pendants for downlights, installing extra large cooking appliances and so on. As you want to move the consumer unit to another room, this would also be a good time to rewire to save extending all the existing cables to the new position. If you are planning to fully decorate the house do any rewiring first!

If you do decide to rewire, while the floorboards are up consider installing TV/Satellite/phone points and network points throughout. Also check the condition and function of, and that there are an adequate number of smoke alarms installed.

 

[brianmoooore]

Couple of extensions since it as built, and now more alterations to the structure. There comes a point when it makes more sense to start again than to extend the extensions.
It's not only the condition of the wiring to consider, but the expectations of the installation as well. I started electrical contracting in the '70s, and have only recently stopped, and towards the end of my career it wasn't unusual to fit more lighting points and socket outlets in just the kitchen, than in the whole of a similar sized house in the '70s.

 

[westward10]

It has EN60898 devices fitted so it is 1991 onwards because EN680898 superseded BS3871 in 1991.

 

[thedawnbefore]

I would estimate early 90's for the CU, the wiring could be older, do you know the exact age of the property.

Thanks. Yes it was built in 1970. I'm led to believe this means it was probably PVC and on further research the standards labelled on the CU are early 1990's.

 

[thedawnbefore]

It has EN60898 devices fitted so it is 1991 onwards because EN680898 superseded BS3871 in 1991.

thanks, very helpful!

 

[westward10]

The wiring in my house is 90% original from 1971.

 

[thedawnbefore]

Couple of extensions since it as built, and now more alterations to the structure. There comes a point when it makes more sense to start again than to extend the extensions.
It's not only the condition of the wiring to consider, but the expectations of the installation as well. I started electrical contracting in the '70s, and have only recently stopped, and towards the end of my career it wasn't unusual to fit more lighting points and socket outlets in just the kitchen, than in the whole of a similar sized house in the '70s.

Thank you, good to know. I'm erring towards a full rewire but hard to estimate the scope given they're not allowing visitors.

 

[SJD]

Thanks. Yes it was built in 1970. I'm led to believe this means it was probably PVC and on further research the standards labelled on the CU are early 1990's.

PVC wiring from circa 1970 is often good condition, so long as you don't have a case of "green goo" which can affect cables from late 1960's to around 1970 or 71 (google it, if not familiar). Tell tale signs are streaks of green oozing from switches or sockets, etc.

 

[thedawnbefore]

Another clue being that the meter is 5+ meters away in another room (a separate garage that was added 10+ years after the house was built) and has a card labelled \'99'. I'm thinking of moving the CU next to it again as part of the intended works. It's hard to imagine this install being earlier than 1990?

 

[brianmoooore]

PVC wiring from circa 1970 is often good condition, so long as you don't have a case of "green goo" which can affect cables from late 1960's to around 1970 or 71 (google it, if not familiar). Tell tale signs are streaks of green oozing from switches or sockets, etc.

That's also the era of 1.0mm2 cpc in 2.5 T&E. Anyone remember exactly when it was realised it didn't meet the regs?

 

[westward10]

The 1.0 cpc was in existence between 1971 and 1981 which coincided with the first 15th Ed being released in1982 where it was not included unlike the previous 14th Ed. The issue with a 1.0 cpc was where it was protected by a semi enclosed BS3036 fuse.

 

[Dustydazzler]

My dad rewired his house late 70s and it has 1mm cpc on the 2,5

i know because I changed the fuse board about 20 years to a new fandangle Mk split load board when I was an apprentice

 

[telectrix]

when I was an apprentice

was tha 1970's or 1870's?

 

[Dustydazzler]

I there are still peoPoe around from the 1870s i would be very surprised

 

[LastManOnline]

The 1.0 cpc was in existence between 1971 and 1981 which coincided with the first 15th Ed being released in1982 where it was not included unlike the previous 14th Ed. The issue with a 1.0 cpc was where it was protected by a semi enclosed BS3036 fuse.

Downsizing the circuit fuse/mcb could be one solution for that problem.
So if the wiring measures out OK, passes a visual too (no green goo) and finally if its not wired with JB, s under the floor (common in 60,s and 70,s) then I, m personally happy with the status quo.
However, bearing in mind the circumstances of moving into a new hom with possible renovations it is the ideal opportunity to rewire and plan for current and future needs.
I think on balance I might just lean towards a rewire if the budget permits

 

[UNG]

All things considered you are looking at knocking some walls about, with some or all of the wiring potentially 50 years old and relocating the CU would need the wiring extending to the new position add to that is there enough socket outlets as back in the 70's they were few and far between and it may be better to consider the rewire while you have got the mess of the remodelling work