Wiring up the stairs

[prjwarren]

Just in the process of re-wiring my house as i'm completely gutting it. (very old and tired all round)
My question is:
Is it ok to sink wiring into the wall to feed the upstairs?
I will have a 10mm cable to feed the shower, 4 x 2.5mm cables and 3 x 1mm cables.
i ask because normally you can recognise where cables should be by light switches or sockeks above and below and you tend to be wary and check however there looks to be no viable solution to feed upstairs as half the floors are concrete (especially round the consumer unit) and as the consumer unit is under the stairs it makes sense to go straight up.
Am I wrong in doing this?
I would chase and sink the cables and obviously put metal covering on.
Thanks

 

[ebee]

So long as you stick to the "safe zones" (permitted zones) which can be vertical from an accessory (or a consumer unit) and be RCD protected or be greater than 50mm deep and be RCD protected or run surface (ie in trunking) .

I hope you have notified in accordance with Part P.

Note - although surface cable (in trunking) does not require RCD the circuits themselves (or part of) might require an RCD for other reasons such as to RCD sockets and RCD all circuits of the bathroom (actually not a bathroom but any location containing a fixed bath or shower).

It is considered best to interpret "all circuits of the location" for RCD purposes to mean from the consumer unit itself rather than just the part of that circuit just before it enters the bathroom because a fault before the bathroom could cause the cpc (earth) to become charged and bypass the RCD protection - not something I had considered until it was pointed out to me I must admit and makes me glad that I still supplementary bond in bathrooms.

 

[prjwarren]

Ok thank you for that, as I said I was going to sink and cover the cables but wasn't probably going as far as 50mm, not to worry would sooner it's right.
Thanks again, Paul

 

[prjwarren]

 

[ebee]

That metal covering - capping.
It is only intended to protect the cable from accidental damage from a plasterers float etc before the plaster is applied.
It is almost useless against nail, screws, drills etc.
In fact if I'm doing the plastering I never use it.
Capping comes in plastic & metal versions.

The problem with metal ones is I have seen them where a previous nail hole produced shards of metal in contact with live cable beneath it causing the whole capping to become live. A piece of live capping below damp plaster gives a good area of shock risk on a wall if touched! Ouch!

 

[ban-all-sheds]

Just in the process of re-wiring my house

• When you applied for Building Regulations approval, what did you say would be the way you'd ensure compliance with P1?
  
  
• For a circuit to supply a given load, how would you go about deciding what cable and protective device to use?
  
  
• Do you know which circuits can be ring finals and which cannot, and what the advantages and disadvantages of each are?
  
  
• Do you know what the two main lighting circuit topologies are, and what the advantages and disadvantages of each are?
  
  
• How do you calculate maximum demand and how can diversity be used?
  
  
• What are the 3 different types of domestic single-phase supplies provided in this country, how would you recognise them, and what differences do each make to the requirements for the rest of the installation, particularly any outdoor supplies?
  
  
• Can you correctly identify all components and connections of a circuit by method of testing or otherwise? In doing so can you identify or recognise anything wrong or dangerous with the circuit?
  
  
• Do you understand how the way in which you install cables affects how much current they can carry?
  
  
• What are the rules concerning cables concealed in walls, partitions and under floors?
  
  
• What are the rules for cables run outdoors, buried in the ground or overhead?
  
  
• Where cables need to be joined, how should this be done / not be done and in what circumstances are different methods acceptable?
  
  
• Can you identify extraneous conductive parts, and do you know the requirements for main and supplementary bonding of them?
  
  
• Which circuits should be RCD protected?
  
  
• How do you propose to isolate your supply so that you can connect up your new CU?
  
  
• Do you know what tests you would carry out on the installation - what sequence you'd do them in and at what point you would energise the installation, and for each test do you know what is being measured, why it is important, how you would carry out the test, and with what equipment, and what sort of results you would expect to get if everything was OK?

The thing is, rewiring a house, installing new CUs etc is not a trivial job, and I can assure you that it involves knowing far more than you think it does.

Asking questions here can be a useful part of a learning process, but they are not a substitute for proper structured studying. The key term there is "learning process" - you cannot learn all the things you need to know just by asking questions here. It isn't structured enough - it won't provide you with a way to progress where each step builds on what you learned before.

You can't carry out a job of this magnitude by asking whatever random questions happen to occur to you. You've already shown that you have some dodgy misconceptions - what if you get something wrong because you have no idea your knowledge is wrong? What if you miss something because you simply have no idea it even exists, and just don't realise you don't know it?

• //www.diynot.com/wiki/electrics
  
  
• //www.diynot.com/wiki/electrics:books
  
  
• http://web.archive.org/web/20080213151445/http://www.kevinboone.com/electricity.html
  
  
• http://web.archive.org/web/20080213151445/http://www.kevinboone.com/domesticinstallations.html
  
  
• http://www.tlc-direct.co.uk/Book/1.1.htm[/list]I suggest you get stuck into the last link right away - it won't give you design ideas, and unfortunately it doesn't refer to the current edition of the Wiring Regulations, but it's free, and will still give you a good grounding which you can augment with more up to date publications.
  
  Or, if you don't want to live in a gutted house with no electricity for several months, I suggest you get an electrician.
  
  As ever, personal recommendations are always the best way to find a reputable tradesman, but if you're having to go ahead without much in the way of those, or references, don't put any store by registration itself - sadly it is possible to become registered with woefully inadequate qualifications and zero practical experience. You don't have to spend long here to see people cropping up who are registered and "qualified", but who are clearly seriously incompetent in reality and who should not be charging for their services.
  
  You are looking for someone to rewire a house, and it may surprise and dismay you to learn that it is quite possible to become a "certified electrician" without ever having done that before, and without having acquired any of the practical skills needed to do it without half-destroying your house in the process.
  
  It's your money, £'000s of it, and you have every right to ask prospective tradesmen what their qualifications and experience are. Just being listed here is not a good enough guide. No genuinely experienced electrician, with the "full set" of C&G qualifications will mind you asking - in fact he will wish that everyone was like you.
  
  I feel sorry for people who have been misled by training organisations and (shamefully) the Competent Person scheme organisers into thinking that a 5-day training course, a couple of trivial examples of their work and some basic understanding of how to use test equipment will make them an electrician, but not sorry enough to agree with them trying to sell their services to Joe Public.

 

[holmslaw]

..

 

[prjwarren]

Ok I fully understand what you are saying with regards to lack of knowledge and it is for that reason I will be contacting a qualified electrician to;
test the wiring and circits I have done and connect to the consumer unit and certify it afterwards.
With regard to people who don't know what they are doing I contacted an electrician who told me he would charge me £3500 to wire the house after I had stripped it and done his chasing. His materials was way way way over the top. I have bought everything plus some extra to what he was going to do for about £1000 les than he said. On top of that I wasn't happy about the fact he was going to take spurs and go back to back off the ring WHY? he was doing a total re-wire for goodness sake, and just to make me feel like he didn't know what he was doing then told me 6mm cable is ok for a 10.5kw shower.
Oh and I wouldn't get a certificate because that he worked for someone and wasn't able to.
In short, I have gone down this route because of the cost and because of the fact I want to know where and what the electrics are doing in my house. I do not want to take short cut and although not qualified I do have common sense and know how a ring main works how the lights work how much load I am putting on a circit and what items in the house should have there own feed and what should be fused. This is the 3rd house I have renovated and along the way have learned and retained a fair amount of knowledge, not just about electrics but most building work. I add that I do appreciate what you are saying about cvowboys and diy disasters and I cringe when I walk into some peoples houses (friends of mine) and what they have attempted to do and what they have thought is ok. Luckily I'm not one of these and am fortunate enough to recognise a master at work and a cowboy.
Thank you for the links but I have read about 5 books on electrics cover to cover and alredy looked into the regs, just could find out about this.

 

[EFLImpudence]

Oh dear. Wait for it.

 

[prjwarren]

With regard to sinking cables 50mm being structural damage would the solution then be to use plastic box type trunking (so that it is instantly recognisable?) and just make it slightly above flush so that it is not so prominent?
I'm obviously trying to do the neatest job possible and did not really want boxing everywhere. Any suggestions greatly recieved.
Thanks

 

[riveralt]

Ok I fully understand what you are saying with regards to lack of knowledge and it is for that reason I will be contacting a qualified electrician to;
test the wiring and circits I have done and connect to the consumer unit and certify it afterwards.

An electrician belonging to one of the competent persons schemes will not be able to certify your work unless he has been involved with it from the beginning.

With regard to people who don't know what they are doing

Which, given your questions and responses, would be you.

I contacted an electrician who told me he would charge me £3500 to wire the house after I had stripped it and done his chasing. His materials was way way way over the top. I have bought everything plus some extra to what he was going to do for about £1000 les than he said.

Why didn't you get three quotes from someone recommended to you or from a member of the competent persons schemes.

On top of that I wasn't happy about the fact he was going to take spurs and go back to back off the ring WHY? he was doing a total re-wire for goodness sake, and just to make me feel like he didn't know what he was doing then told me 6mm cable is ok for a 10.5kw shower.

I'm glad the alarm bells started ringing.

Oh and I wouldn't get a certificate because that he worked for someone and wasn't able to.

And in view of what you propose you still won't get one.

I do not want to take short cut

but you are!

and although not qualified I do have common sense and know how a ring main works how the lights work how much load I am putting on a circit and what items in the house should have there own feed and what should be fused.

And of course how to test a ring final circuit.

This is the 3rd house I have renovated and along the way have learned and retained a fair amount of knowledge, not just about electrics but most building work.

All properly complying the Building Regulations and BS7671 of course with certificates et al.

Thank you for the links but I have read about 5 books on electrics cover to cover and alredy looked into the regs, just could find out about this.

If you feel that you are competent to carry out this work and have read these books then why are you asking questions like this on a DIY forum. If you feel you are competent then follow the correct procedure and apply to your local authority building control - they are there to help you.

 

[riveralt]

With regard to sinking cables 50mm being structural damage would the solution then be to use plastic box type trunking (so that it is instantly recognisable?) and just make it slightly above flush so that it is not so prominent?
I'm obviously trying to do the neatest job possible and did not really want boxing everywhere. Any suggestions greatly recieved.
Thanks

Why are you seeking to bury cables at 50mm - why not 20/25mm? - As long as the cables are in the safe zones and the circuit complies with BS7671 what is the problem?
What type of circuits have you designed?
How are they to be protected?

Reading books is one thig - understanding them is another.

Either speak to BC or get a proper electrician in to do the work.

 

[prjwarren]

Your right of course, this site should not be called DIYnot as it is really for experts to have a debate and critisise us lower mortals. The gods of electrics wouldn't lower themselves to come down to our level and check someone else's work, even if it was common sense but then I forgot! It is only us lower mortals who ever make mistakes and electricians didn't have to learn anything, they just plugged themselves in uploaded all relevant data and never ever asked anyone else for advise!

 

[riveralt]

Your right of course, this site should not be called DIYnot as it is really for experts to have a debate and critisise us lower mortals. The gods of electrics wouldn't lower themselves to come down to our level and check someone else's work, even if it was common sense but then I forgot! It is only us lower mortals who ever make mistakes and electricians didn't have to learn anything, they just plugged themselves in uploaded all relevant data and never ever asked anyone else for advise!

Competent Person Scheme members - not certifying your work - has nothing to do with the gods and mortals reference - its all to do with common sense, which you classed yourself as having, but in this instance at least seem to have lost.

One thing you do learn in this job - is that you never ever stop learning. I have absolutely no problem in giving anyone advice - but I try to judge the advice on the initial question asked, the responses given and scale of the work proposed. In all three cases I was not confident that you are competent enough to do this work.

I say again if you feel that I am wrong and you are truly competent to design, install and test what is a major electrical job then you should apply to the BC. If not then you should get the help of an electrician and not try and pick up bits and pieces from this forum.

 

[flameport]

The gods of electrics wouldn't lower themselves to come down to our level and check someone else's work, even if it was common sense

Electricians can of course check other people's work, and issue a report on the condition of it. However the issue is that the work you are intending to do is notifiable, so there are only two legal options:
1. Notify building control and pay the required fee before the work starts.
2. Have a member of a competent persons scheme do the work and notification for you.

If you install these circuits in your house without notification, you are breaking the law. Attempting to then get an electrician to notify the work you have done simply won't happen, as all of the schemes specifically prohibit this.