Question about electric rewiring

Joined
2 Feb 2016
Messages
390
Reaction score
5
Country
United Kingdom
A friend of mine's property has the old fuse wire type consumer unit. Part of building refurbishment to upgrade ceiling lights etc a company is quoting for complete re-wiring to change consumer unit. My question is, with an old system like that is a complete re-wiring needed? Does old wiring eventually need to be replaced?
 
Sponsored Links
Wiring will all need replacing eventually, but it depends on how old, what type and whether it's still practical to use. Many older properties only had a single socket in each room, and even if the wiring was perfect, that's simply nowhere near enough for a modern home.

The presence of a fuse wire fusebox doesn't automatically mean that rewiring is required - they were still being installed in the 1980s and even early 1990s, and wiring of that age is very likely still usable.
 
Thanks for that.

So just out of curiousity a new build this day and age that has new wiring, eventually at some point will the wiring need changing on that too?
 
So just out of curiousity a new build this day and age that has new wiring, eventually at some point will the wiring need changing on that too?
As far as the actual wiring is concerned, probably not in your lifetime. For obvious reasons, no-one yet knows for certain, but PVC wiring is likely to last for at least 100 years, quite probably more. A re-wire might be undertaken before that for other reasons ('requirements' evolve over time, and if they change enough, a 're-wire' may be the simplest solution), but not because there was any problem with the actual wiring, per se.

Kind Regards, John
 
Sponsored Links
Thanks for the replies. For my friends property, just out of curiousity a small 3 or 4 bed house in London how much should a complete rewire with new consumer unit typically cost London price?
 
The mineral insulated wiring of the 1920's is likely still OK today, but the rubber is well past it's use by date, PVC has had problems, the plasticizer can leach out making it brittle, but this is rare, also if over loaded it can be damaged, but in the main PVC cable lasts a long time.

My granddads house wired 1920's had two 15 amp sockets one in hall and one on landing, iron plugged into the lights, dads house 7 sockets, one in each room and on landing, that was 1954, by 1978 when my first house built, still only 4 circuits, sockets, lights, immersion and cooker, but many more sockets, think there were 6 in the kitchen alone, by 1985 when this house built two lighting and two sockets supplies, lights split up/down, sockets side to side.

The introduction of 30 mA RCD's resulted in sockets also split up/down so that the lights and sockets for each room are not on the same RCD, idea is should you get a shock from socket supply you will not be plunged into darkness, but the distribution board has also changed, the so called high integrity so some circuits on RCBO's so sockets again split side to side, which means if there is a problem don't need extension leads up/down stairs, more even loading, and less wire used so better loop impedance.

There are other factors, like cables being run in the cavity wall, then insulation added, so each premises has to be assessed, my dad's house was rewired, but some items were left, the kitchen had been rewired before the full re-wire, and the wet room was also new, so those area were not done. But the rewire resulted in loss of supply to loft except for lights, and reduced supply to garage, and some walls with no sockets due to being papered and hard to redecorate after.

I did not re-wire it myself, main reason was speed, costing £600 a week accommodation for mother while being rewired, so speed was important. At one point there were 6 electricians in the house, I think the guy under estimated how long it would take, seem to remember £3000 and in North Wales and as said some bits not done, detached 3 bedroom house.

But pricing is hard, the different firms suggested different levels of re-wiring, some included LAN cables and TV, some included making good, the one I used did not include making good, however they were good in considering the work needed to make good after. So yes same as cost of second hand car, as so many variables. Council houses were re-wired all surface near where I live, and each house took two days, all done the same, and if tenant had changed things they were charged to correct them, for example if they had fitted a chandelier, it was removed, dumped, and tenants charged.

Today rules don't allow trunking where it could fall off in a fire, and so surface wired re-wires have gone up in price, plus metal consumer unit, and so often it can't be fitted in old location, dads house consumer unit under the stairs, I don't think it should have been fitted there, but was not my decision, it was put where old one was, which was silly as mother could not access it in wheel chair. This all reflects on the price.
 
When I visited Ireland everything seemed more expensive than the UK with the exception of diesel fuel.
 
Last edited:
When I visited Ireland everything seemed more expensive than the UK with the exception or diesel fuel.
Yes, well that's true of course. But - and not forgetting we're talking about London here also - I still think it's a gross underestimate. It might be possible as a price, but certainly not likely.

I recently priced a 3 bed in Donegal at around €8k + VAT, and recently completed a 4 bed in Donegal at €10k + VAT.
 
Yes, well that's true of course. But - and not forgetting we're talking about London here also - I still think it's a gross underestimate. It might be possible as a price, but certainly not likely.

I recently priced a 3 bed in Donegal at around €8k + VAT, and recently completed a 4 bed in Donegal at €10k + VAT.

This answers my mind voice. Fair enough
1. Why some handymen from Europe are so successful in the UK with their business (plumbing, construction, wiring, painting, refurbishments) - Pricing.
2. Why most of the families don't update / refurbish their homes during their life time ?

British Traders and Irish traders(plumbing, construction, wiring, painting, refurbishments) have to make sense with their pricing and ground realities which reflects Trademanship price for the earnings of the people, so many people come forward for home maintenance. Else you have few customers.


Regards
 
Last edited:
A friend of mine's property has the old fuse wire type consumer unit. Part of building refurbishment to upgrade ceiling lights etc a company is quoting for complete re-wiring to change consumer unit. My question is, with an old system like that is a complete re-wiring needed? Does old wiring eventually need to be replaced?
Everything degrades eventually. The question is how long it will take and in some cases we just don't know.

Old rubber wiring tended to go hard and brittle over time. As long as it's not disturbed the insulation still insulates ok, but if it is disturbed it can easily crack. As a result if old rubber wiring is found the recommendation is to rewire as soon as practical and to minimise disturbance to the installation in the meantime.

IIRC PVC wiring as we know it today became common sometime around the 1960s or 1970s and most of it is still good today, though there were some batches which had problems with the plasticiser leaching out.

I think between the rubber era and the PVC era a variety of other plastics were tried, many of which are also still good today but i'm not 100% sure on that.

Eric mentions mineral insulated cable, AIUI the cable itself lasts practically forever as long as moisture is kept out, but if it's poorly terminated and moisture gets in then insulation resistance can quickly degrade. It also needs special "pots" to terminate it and I don't think you can easilly get the pots for imperial sized mineral insulated cables anymore for modification or repair work.

Another problem is that requirements change over time. Different people respond to these changing requirements in different ways. Some people may just work around them by using lots of extension leads. Others respond by adapting and extending the fixed wiring. Such work may or may not have been done in a safe and compliant manner.

Another problem is that lighting circuits wired in the 1960s and earlier may lack an earth connection. That seriously limits your options for doing any work on the lighting circuit without re-wiring it.
 
Based on my experience of PVC BS6004 cable installed from 1980 on, I would say it would last around 100 years as long as it were not subjected to extremes of temperature during its lifetime.

Edited for clarity.
 
Last edited:

DIYnot Local

Staff member

If you need to find a tradesperson to get your job done, please try our local search below, or if you are doing it yourself you can find suppliers local to you.

Select the supplier or trade you require, enter your location to begin your search.


Are you a trade or supplier? You can create your listing free at DIYnot Local

 
Sponsored Links
Back
Top