T
teaboyjim
Are there tests that an electrician can do to determine if a new electrical installation is needed
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There are not always definitive answers, different electricians will have different opinions. Some electricians will sadly use inspection and testing as a vehicle to drum up work that isn't really necessary.
Testing can definitively state that something is bad, but it can't definitively state that it is good. Inspection is as important, if not more so than testing in determining the state of an installation, but testing and inspection is not a pancea. You can get an electrican installation condition report done and you will probablly have to at some point if you intend to rent out the property, but there isn't much point doing an EICR if a quick visual inspection would be enough to tell you it's rewire time.
Broadly speaking though, there are a number of reasons one might rewire some or all of the circuits in a property.
* The wiring is life-expired. Rubber insulation can harden and crack with age. Rubber has not been used for normal house-wiring cable for decades, so a house wired in rubber is a house that most electricans would say needs a rewire. PVC on the other hand lasts virtually forever if it wasn't defective.
* The wiring is defective, for example some batches of older PVC cables had a bad plasticiser formulation that leaches out producing "green slime". There was also a brief foray into using aluminium cores for domestic wiring which lead to unreliable terminations.
* The wiring has been damaged, for example by fire, floor or rodents, or sometimes because of overloading.
* The wiring is not fit for purpose. The expectations we have of our electrical installations have changed over the years and there comes a point in planning out modifications and extensions where you may decide it's easier to start from scratch.
* The wiring is full of horrible bodges, this follows on from the previous, as expectations have changed people have made DIY modifications to their electrical installations and not all of them did it in an acceptable manner. Stripping out the horrible bodges may leave you with an installation that is not fit for purpose.
* For lighting wiring it lacks an earth conductor, often lighting wiring without an earth will also be life-expired rubber, but I belive there was a period when plastic cables without earth conductors were used.
Can you post pictures of the installation?
Do you know when the property was built?
Testing can definitively state that something is bad, but it can't definitively state that it is good. Inspection is as important, if not more so than testing in determining the state of an installation, but testing and inspection is not a pancea. You can get an electrican installation condition report done and you will probablly have to at some point if you intend to rent out the property, but there isn't much point doing an EICR if a quick visual inspection would be enough to tell you it's rewire time.
Broadly speaking though, there are a number of reasons one might rewire some or all of the circuits in a property.
* The wiring is life-expired. Rubber insulation can harden and crack with age. Rubber has not been used for normal house-wiring cable for decades, so a house wired in rubber is a house that most electricans would say needs a rewire. PVC on the other hand lasts virtually forever if it wasn't defective.
* The wiring is defective, for example some batches of older PVC cables had a bad plasticiser formulation that leaches out producing "green slime". There was also a brief foray into using aluminium cores for domestic wiring which lead to unreliable terminations.
* The wiring has been damaged, for example by fire, floor or rodents, or sometimes because of overloading.
* The wiring is not fit for purpose. The expectations we have of our electrical installations have changed over the years and there comes a point in planning out modifications and extensions where you may decide it's easier to start from scratch.
* The wiring is full of horrible bodges, this follows on from the previous, as expectations have changed people have made DIY modifications to their electrical installations and not all of them did it in an acceptable manner. Stripping out the horrible bodges may leave you with an installation that is not fit for purpose.
* For lighting wiring it lacks an earth conductor, often lighting wiring without an earth will also be life-expired rubber, but I belive there was a period when plastic cables without earth conductors were used.
Can you post pictures of the installation?
Do you know when the property was built?
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Read this best practice guide it does give some pointers, pages 7,8 and 13 show pictures of rubber insulated cable and the problem as it degrades.
Some of the things we are told to look for don't always make sense, I have seen where the grommet is missing, however the plaster is holding the cable in such a way it could not possibly cause a problem, so it is not always cut and dried.
When mothers house was rewired, after some of the old sockets that used PVC cables were reconnected, so some one may assume this house has been rewired and all is good, but can still be some odd bits, where for example the out house was wired using conduit in the concrete and really hard to rewire, so old wires used.
The IET does model forms down load them and try filling them in, there will be bits you can't do, but last but last 2 pages should help, it also gives you an idea of what an EICR is all about.
Most of the time you look at an old house and think to be on the safe side it needs a new consumer unit (also called fuse box or distribution box) so RCD protection can be added, what is hoped is once that is added the installation will fail safe, so start with picture of the CU, see what people on here say, if it is needed then likely the electrician fitting it will give you some report on the state of everything else.
Some of the things we are told to look for don't always make sense, I have seen where the grommet is missing, however the plaster is holding the cable in such a way it could not possibly cause a problem, so it is not always cut and dried.
When mothers house was rewired, after some of the old sockets that used PVC cables were reconnected, so some one may assume this house has been rewired and all is good, but can still be some odd bits, where for example the out house was wired using conduit in the concrete and really hard to rewire, so old wires used.
The IET does model forms down load them and try filling them in, there will be bits you can't do, but last but last 2 pages should help, it also gives you an idea of what an EICR is all about.
Most of the time you look at an old house and think to be on the safe side it needs a new consumer unit (also called fuse box or distribution box) so RCD protection can be added, what is hoped is once that is added the installation will fail safe, so start with picture of the CU, see what people on here say, if it is needed then likely the electrician fitting it will give you some report on the state of everything else.
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