Plasterer damaged cable. Is repair okay?

[JohnW2]

How on earth is someone supposed to know that that lot is in the wall when they come to put up a picture etc. ???

We were told that the problem is in "... a cable which runs straight down to a light switch", so if the 'someone' knew anything about so-called 'safe zones' (aka 'danger zones'!) he/she should know that it was possible (probably 'likely') that at least a cable would be buried there!

Kind Regards, John

 

[robinbanks]

Because it's in a safe zone, of course!

 

[securespark]

Strictly speaking, I suppose the answer is yes. However, I'm sure that many of us would feel that 'plastering in' any junction box (even if 'maintenance-free') is far from a good (or 'nice') idea.

Kind Regards, John

Then you must also agree that putting a MF JB under a floor is far from a good idea.

 

[bernardgreen]

Then you must also agree that putting a MF JB under a floor is far from a good idea.

I would agree with that.

 

[JohnW2]

Then you must also agree that putting a MF JB under a floor is far from a good idea.

"Far from a good idea" is putting it far too strongly - but, yes, my (very probably unfounded) 'theoretical uncertainties' relate to 'spring terminals', per se - whether buried in plaster, under floors or even 'accessible'. It's probably just me - I function in a highly evidence-based world, so am always a little uncomfortable about "theoretical uncertainties", even if my concerns about them are "very probably unfounded".

With the best will in the world, there is a limit to what can be discovered by 'accelerated testing' - if one wants hard evidence about what a product will be like after 50 years in-service, one really needs to wait until it has been in widespread use for 50 years! Think of medicines - would you be happier about the safety of a medicine which had been in very widespread use for many decades or one which had appeared far more recently and, even today, is not yet in 'very widespread use'?

We can probably agree that the ideal is not to have any ('unnecessary') joints in cables, even more so if those joints are 'not accessible', no matter what the nature of the joint.

What I don't know is whether MF JBs offer any significant ('safety') advantage over conventional (screwed terminal) ones (i.e. whether they are a solution to a problem which significantly exists). My experience is obviously very limited but I have lived in, and known about, many properties whose electrical installations involve countless conventional (screwed terminal) JBs and I have never experienced, nor heard about, a problem arising as a result of those joints deteriorating over time. If such problems are extremely rare, that obviously raises the goalpost as to how good a 'better alternative' (with 'long-term uncertainties') has to be in order for its use to be justified, particularly during the period when there are uncertainties due to a lack of widespread very long-term use..

For what it's worth, and given that I am certainly no authority on materials, in other (non-electrical) contexts I've come across bits of metal which started their life as 'springs' but which after many years/decades in service have lost some (in some cases most/all) of their 'springiness' - which obviously helps to fuel my 'uncertainties'.

Having said all that, I am personally very inconsistent/illogical/ daft in my behaviour since, whenever I have floor boards up for some other reason, I take the opportunity to replace conventional (screw terminal) JBs with MF ones "because that's what people expect" - which is particularly daft given that no-one inspecting the electrical installation will know what it beneath the floors! Human nature is not necessarily logical!

It's certainly the case that were it not for 'regulations', I would be be comfortable with a situation in which all the ('unavoidable') JBs were conventional ones (although I don't think I would ever be happy with burying any type of JB in plaster!).

Kind Regards, John

 

[robinbanks]

Though if you go to the extent the DNO do to splice a new incomer cable into the existing network, it's ok.. ?

 

[JohnW2]

Though if you go to the extent the DNO do to splice a new incomer cable into the existing network, it's ok.. ?

What is "OK"?

Kind Regards, John

 

[sparkwright]

Then you must also agree that putting a MF JB under a floor is far from a good idea.

Not sure what you mean - putting a MF JB under a (suspended) floor is surely far better than having it buried in a solid wall.

Isn't it?

 

[securespark]

No. Not if the choice is to rip up a tiled, laminate or wet or dry UFH floor or the ceiling below.

 

[JohnW2]

Not sure what you mean - putting a MF JB under a (suspended) floor is surely far better than having it buried in a solid wall. Isn't it?

I would say that it usually is (give or take difficulties in getting the floor up!). However, as I wrote in response to secure's comment, if one has uncertainties about 'sprung terminals' then they exist no matter where they are located - simply easiest to inspect/maintain if accessible, not so easy if under a floor, and even less easy if buried in plaster!

Kind Regards, John