Need Advice - New Kitchen Rewire

[Stephen Paul Jones]

Hi Guys
New to forum and enjoying reading the threads, all interesting, so..
Looking to re-wire my kitchen due to re-fit and some of you will be unhappy (understandibly) as I am not a qualified sparky, but I will notify building control and get the work certified and passed. This is simply an interest of mine and I enjoy it, I certainly don't intend killing myself or anyone else in the process and will get in local authorities for cert...so here goes, lot's of reading, bear with me, as I really can do with the help to clarify if I am wrong alltogether or on the right track being a diy'er.

I am now installing at home a built in oven 3.39kW, microwave 900w, induction hob 7.5kW, Fridgefreezer, under counter freezer, washing machine and Cooker hood 250w.

All appliances with 4 meters of DB and Clipped direct to wall behind open cavity, not insulated, 75mm cavity to address 50mm depth regs, don't intend to mechanically protect wiring, due to 75mm deep and RCD protected. Walls plasterboard lined for convenience, all wiring within prescribed zones!

So, would this be correct for regs... I have a
Wylex,14way Split Load DB, 2x 80A/30ma RCD's with the addition of potential seperated RCBO's below:

Oven and Induction Hob - DB 32A RCBO
Appliance's Total = 10.89kW- 47.34A using diversity and if maths correct:-
30% = 11.2A, 11.2A+10A= 21.2A total, so from DB using 6mm cable via 45A CCU down to Dual Cooker Outlet using 6mm cable, seperated and terminated at both appliance's using 6mm cable.

Fridgefreezer and Freezer - on separate 20A RCBO dedicated radials using 2.5mm cable via Switched FCU's down to flex outlet plates.

Washing Machine - I'm sure read somewhere regarding Nusiance tripping, not sure if 17th Edition about putting the likes of the washing machine again, on a dedicated curcuit, 20A RCBO using the usual method mentioned or, I could spur off rfc with Switched FCU down to flex outlet plate. This was when I was told I was over the top and pointless by a Sparky, always learning, even at 50.

Finally Microwave(900watt) and Hood(250watt) total 5A
Could these both appliances be powered via a junction box to separate FCU's and outlet plates, on 10A RCBO dedicated radial curcuit.

I have room for these dedicated radials and can keep the RCD protected Split Loads seperate, would this then be the making of a High Integrity Unit?
DP RCBO's or SP RCBO's, so many views on this, not sure.

If you have read this far, I commend you for your patients and appologise if my terminology is not adequate and certainly look forward to your comments and would really appreciate the feedback.

 

[Barnaby Stedman]

Do you realise the difference between a DP RCBO and a SP RCBO?

 

[Pete999]

may have this wrong, but you mention you are fitting a dual RCD CU WITH 2 X 80Amp RCDs why are you intending fitting RCBOs, there will be no need as your outgoing circuits will be RCD protected by the 2x RCD s in the CU?

 

[rolyberkin]

Without sounding negative how are you going to test all of this? It's all very well putting cables into sockets and clipping them to the wall but if you aren't going to test it properly and actually understand the results of the tests getting LABC to sign it off won't mean a thing. Also an electrical certificate requires three signatures, one for design, one for installation and one for inspection and testing, how will this happen? How will you know if it is safe prior to flicking the switch?

 

[Dustydazzler]

Without sounding negative how are you going to test all of this? It's all very well putting cables into sockets and clipping them to the wall but if you aren't going to test it properly and actually understand the results of the tests getting LABC to sign it off won't mean a thing. Also an electrical certificate requires three signatures, one for design, one for installation and one for inspection and testing, how will this happen? How will you know if it is safe prior to flicking the switch?

Bang Test ?

 

[Wilko]

Hi - Like any learner, you should not attempt hazardous tasks for which you’ve not been trained. Maybe a find a friendly local Electrician to work with?

 

[Nelder]

I'm sorry but its clear you don't fully know what your doing. There can be no doubt when electricity is involved.

 

[Stephen Paul Jones]

Yes, agree totally with all comments. Wilko, I will get a local electrician to work with and for the reasons Rolybarkin mentioned. Pets 999, I think I will replace with a full board of RCBO's, understand what you are saying, RCD's are already in situ and thought it would be a better arrangement if some curcuits like the freezer are separated from the bank of RCD protected curcuits. Less chance of tripping by isolating those curcuits, especially when you have a fridgefreezer full of grub. apprciating the comments...

 

[remedial]

for the oven I'd put in a 10mm cable for future proofing.

all the separate radials are overkill. if isolation is needed thats what the FCUs are there for.

 

[Stephen Paul Jones]

I thought that.. now you have mentioned it, I will. cheers Remedial. I agree overkill perhaps, but I think it will be cautious and good practise from a design layout to have at least the fridgefreezer and has I have with the garage on their own separate RCBO curcuits, preference I suppose. Thanks Guys

 

[Intoelectrics]

There's nothing wrong with discrimination in any electrical design, usually more the better. But there is no need to over kill it, which would be costly for no particular good reason. Individual RCBO's are a preferred method and much better for kitchen installations where there is the likelihood of many different electrical appliances being used.
Much more sensible to get a local electrician in to design the install for you, maybe be ok with you working on it and then the sparky signing it off after completion.
Testing of these systems is a requirement and requires the correct testing equipment, knowledge and understanding to complete competently.
If you proceed on your own you could find you have made a costly mistake when its too late. Better to learn as you go with the assistance of a knowledgeable and experienced time served qualified professional.

 

[Midwest]

What about SPD's & AFDD's?

 

[Stephen Paul Jones]

I have mentioned SPD's to some sparky's locally and I see the sense of them with the amount of electronics within households today, but one sparky told me SPD's are a pain in the ar** to install due to the complicated risk assessment paperwork involved, but reading the regs as a DIyer that I am, this is now compulsory on a single dwelling if you do not complete a risk assessment, am I correct Midwest.

 

[Octopus]

but reading the regs as a DIyer that I am, this is now compulsory on a single dwelling if you do not complete a risk assessment, am I correct Midwest.

No.

 

[Stephen Paul Jones]

Intoelectrics... agree, I'm not a sparky, but feel that RCBO's can fit into design alongside RCD protected circuits for discrimination as you stated, especially the kitchen. Also agree with calling in an electrician to assess my install and signing off before energising system. Doing this for the enjoyment and knowledge...but safety is paramount!

 

[SparkyChick]

Intoelectrics... agree, I'm not a sparky, but feel that RCBO's can fit into design alongside RCD protected circuits for discrimination as you stated, especially the kitchen. Also agree with calling in an electrician to assess my install and signing off before energising system. Doing this for the enjoyment and knowledge...but safety is paramount!

As you're in Cardiff, you cannot use the third party certification route. In Wales we are required to follow the 2010 version of Approved Document P which (a) makes the kitchen a special location requiring any work involving changing the fixed wiring a notifiable job and (b) did not contain the provision for Third Party Certification.

This provision was introduced into Approved Document P in 2013 which is after the Welsh Assembly took control of the building regulations (which is why we're still working to the 2010 version).

 

[Stephen Paul Jones]

Sparkychick all noted, but go to your nearest wholesaler, Screwfix or Toolstation near you, they are filled with experience but unqualified time served sparky's (very good one's) who are first, second and third fixing, just to get their certs at the end of the job from a qualified electrician. This is the reality as you know well, I know at least three great successful contractors who do this. Inspection and testing complete, all passed, cert supplied, money changes hands, this is the way of the world. Work is safe, customer is safe and more people earning a living...what's new!!

 

[Pete999]

Sparkychick all noted, but go to your nearest wholesaler, Screwfix or Toolstation near you, they are filled with experience but unqualified time served sparky's (very good one's) who are first, second and third fixing, just to get their certs at the end of the job from a qualified electrician. This is the reality as you know well, I know at least three great successful contractors who do this. Inspection and testing complete, all passed, cert supplied, money changes hands, this is the way of the world. Work is safe, customer is safe and more people earning a living...what's new!!

Screwfix and Toolstation all timed served Sparks??

 

[Stephen Paul Jones]

More Sparks transferring to Screwfix and Toolstation daily, that's why the likes of Denman's and other Electrical wholesalers are closing branches. Quicker service, Guaranteed more items available in stock, most rates compare with wholesalers and all at the touch of an iPad.

 

[Octopus]

Screwfix and Toolstation all timed served Sparks??

call him Sherlock!

 

[Octopus]

More Sparks transferring to Screwfix and Toolstation daily, that's why the likes of Denman's and other Electrical wholesalers are closing branches. Quicker service, Guaranteed more items available in stock, most rates compare with wholesalers and all at the touch of an iPad.

I've given you a "disagree" because you are wrong.

House bashers like Screwfix, but their products and stock profiles fall well short of the kit most of us actually need.

Anyway, I thought you were a DIYer? If you know so much about the habits of sparks why don't you ask them?

 

[SparkyChick]

The fact that it's taking place does not make it right or legal.

If something were to go wrong I suspect everyone's insurance company would be looking for a get out clause and they'll have been handed one by the people who do this.

I've been asked to do it and refused, just as I've been asked to provide a satisfactory EICR for an installation that was far from it... funnily enough after a 'spark' (and I use the term loosely) had done a disappearing act when it came to signing off because his mate wouldn't supply him with a cert like he usually did. The job had the potential to be truly shocking in the worst way possible... I believe the client eventually found someone mug enough to sign it off though, but that's OK because it's just someone earning a living.

Ultimately I guess it's down to ones character... whether or not they want to knowingly break the law and assist someone else in doing so. Personally I like to sleep soundly at night which is why I don't engage myself in drive by EICRs and signing off other peoples work.

 

[Stephen Paul Jones]

call him Sherlock!

My name is not Sherlock!!

 

[Octopus]

My name is not Sherlock!!

I was quoting Pete999

 

[Stephen Paul Jones]

I totally commend you for that statement and wholly agree with every word you said, but let's put this in context, as you know there are very good electricians who have their work passed off and do earn a living making the end user's environment safe with good design, good practice and a competent and qualified person to complete Inspection and testing at end of install, this is so true of so many...but, so is the fact that irresponsible contractors sign off "Cowboys" work to the danger of the end user...and should be jailed for this practice, this I also understand! I know of one electrician who is very well respected for his knowledge and 30 years experience in this trade and contractors have told me that he is top of his game and.... take advice off him, yet the contractors sign off his work because he does not want to sit the exams and never will!
So, I was just trying to make this point, of course dangerous work cannot be condoned and I would not sleep at night either. Look, this swings both ways... as an end user, about 10 years ago, my bro had an electrician to put in garden lights, and a day before he finished, me... "a DIYer" turned up at my brothers home and found that the termination of the SWA into the junction boxes and light fitments was so shoddy to the point that within a few days there would have been an ingress of water onto live connections, the copper compression glands had not been tightened and the gland sleeves were not present on some fitting, this electrician was signing his own work off the next day leaving a potential death trap and my brothers kids were 3 and 7yrs at the time, I threw him offsite as he argued this was to regs. So, there are as many "electricians" out there that are even more dangerous than "competent persons", as they have the right to sign off their own poor workmanship!! No trade is exempt from this behaviour, unfortunately.
I'm not a Spark, I have been told by a Spark to sit the Part P, but I am fortunate to have a successful career elsewhere, but does not stop me enjoying and being interested in this trade. I respect Good Practise Qualified Electricians and that is why I am on this site to learn without killing anyone!

 

[Stephen Paul Jones]

I was quoting Pete999

That's me getting it wrong, sorry Murdoch

 

[Dustydazzler]

When doing house rewires I almost exclusively get my junk from Screwfix and toolstation

Occasionally use TLC for bigger trunking etc

Odd ball bits off eBay etc

Hardly ever use any of the traditional wholesalers these days

 

[Stephen Paul Jones]

Screwfix is opening a branch monthly, traditional wholesalers are diminishing, unfortunately true, not just in this sector. Wholesalers do not invest in the services and software to allow local pick up within the hour, online shopping all hours, viewing local branch stock immediately, as I mentioned earlier through talking to local sparks, most are converting, simply due to the convenience.

 

[Dustydazzler]

What absolutely killed it stone dead for me was when my local Screwfix could offer me twin and earth cable about 20% cheaper than my local cef or wf

I used to do a lot of subby house bashing for a big electrical firm who were buying twin and earth by the pallet.
I could still get a roll of 2.5 cheaper in Screwfix

 

[Stephen Paul Jones]

If you talk to the local Branch Managers, Screwfix are now honed in on all other electrical suppliers and are now gunning for the majority of business to be had, they can only improve with the Backing of the Kingfisher Group. Their prices will get keener and will start stocking the more specialised products as described by Murdoch.

 

[Midwest]

Not wishing to divert the thread, but the OP started it

When I was contracting, small turnover, I used both a wholesaler (Rexel) and Screwfix. I primarily used Screwfix, for MK switches & sockets, which were sourced cheaper than Rexel. The other bread & butter stuff Rexel were cheaper, including tw&e. You just have to ask for a better discount with your wholesaler. Screwfix are open at the weekends, my Rexel isn't.

True enough, you can sit on a PC, and get stuff not in stock next day from Screwfix, & see the price, but you can get a similar service from a decent wholesaler.

Agree though, the only 'local' electrical wholesaler I had, has gone under recently.

 

[Zerax]

If you talk to the local Branch Managers, Screwfix are now honed in on all other electrical suppliers and are now gunning for the majority of business to be had, they can only improve with the Backing of the Kingfisher Group. Their prices will get keener and will start stocking the more specialised products as described by Murdoch.

I've noticed that Screwfix are more expensive on some items these days... it's starting to be a chore comparing pricing with Toolstation on the wholesalers. I even find that B&Q (also part of Kingfisher) can be cheaper than Screwfix sometimes... I think generally they're getting very clever with pricing, making more margin in the process.

 

[Stephen Paul Jones]

I agree with you all, it is a real shame that even the independent wholesalers are few and far between, but the likes of Screwfix and Toolstation are well-oiled machines with big funding and will only improve, and yes, they will slip in some raised prices here and there (clever retailing). But, I really do hope that the wholesalers survive, because the giants are dominating all sectors of the markets, just look at how empty the high streets are... anyway my apologies, I have diverted the thread, I did come on here originally for advice from you experienced guys and have been well satisfied with the advice received, learned and few things along the way and have had some enjoyable debates and discussions with you all. Glad I joined the forum

 

[Tony Reidy]

Hi Guys
New to forum and enjoying reading the threads, all interesting, so..
Looking to re-wire my kitchen due to re-fit and some of you will be unhappy (understandibly) as I am not a qualified sparky, but I will notify building control and get the work certified and passed. This is simply an interest of mine and I enjoy it, I certainly don't intend killing myself or anyone else in the process and will get in local authorities for cert...so here goes, lot's of reading, bear with me, as I really can do with the help to clarify if I am wrong alltogether or on the right track being a diy'er.

I am now installing at home a built in oven 3.39kW, microwave 900w, induction hob 7.5kW, Fridgefreezer, under counter freezer, washing machine and Cooker hood 250w.

All appliances with 4 meters of DB and Clipped direct to wall behind open cavity, not insulated, 75mm cavity to address 50mm depth regs, don't intend to mechanically protect wiring, due to 75mm deep and RCD protected. Walls plasterboard lined for convenience, all wiring within prescribed zones!

So, would this be correct for regs... I have a
Wylex,14way Split Load DB, 2x 80A/30ma RCD's with the addition of potential seperated RCBO's below:

Oven and Induction Hob - DB 32A RCBO
Appliance's Total = 10.89kW- 47.34A using diversity and if maths correct:-
30% = 11.2A, 11.2A+10A= 21.2A total, so from DB using 6mm cable via 45A CCU down to Dual Cooker Outlet using 6mm cable, seperated and terminated at both appliance's using 6mm cable.

Fridgefreezer and Freezer - on separate 20A RCBO dedicated radials using 2.5mm cable via Switched FCU's down to flex outlet plates.

Washing Machine - I'm sure read somewhere regarding Nusiance tripping, not sure if 17th Edition about putting the likes of the washing machine again, on a dedicated curcuit, 20A RCBO using the usual method mentioned or, I could spur off rfc with Switched FCU down to flex outlet plate. This was when I was told I was over the top and pointless by a Sparky, always learning, even at 50.

Finally Microwave(900watt) and Hood(250watt) total 5A
Could these both appliances be powered via a junction box to separate FCU's and outlet plates, on 10A RCBO dedicated radial curcuit.

I have room for these dedicated radials and can keep the RCD protected Split Loads seperate, would this then be the making of a High Integrity Unit?
DP RCBO's or SP RCBO's, so many views on this, not sure.

If you have read this far, I commend you for your patients and appologise if my terminology is not adequate and certainly look forward to your comments and would really appreciate the feedback.

Your going over the top get a sparks in will save you money

 

[Des 56]

I'm not a Spark, I have been told by a Spark to sit the Part P

What has "sitting the Part P" (whatever that happens to be) got to do with the training required to become a electrician

It seems to me yet again,a building regulation is thought to have something to do with a electrical qualification

 

[Stephen Paul Jones]

Dee56... This suggestion was made to me in a conversation recently by "A Qualified Spark" as I clearly stated in the thread. If the point you just made is relevant and correct, which I have no reason to doubt, then this is directed at your fellow Spark and validates my point made in an earlier thread (Tues 10:41pm), which does give rise for concern, are all Spark's up to the job?

 

[Stephen Paul Jones]

Just a question guys, (back to my kitchen install), I have lifted the loft insulations today (large Bungalow) it is an absolute shambles up there, JB's shoddily put together, no sleeving on any cpc's in the boxes, outside lighting connected directly to 32A FRC with a broken JB and even 1.5 cable from that JB's to a 2g socket, which by the way is supplying my livingroom!... not anymore, I might add.... and I won't even go into the cable routing, mind-boggling. So... comes to my question, is it a good idea to lay 150mm medium duty cable tray on ceiling joists to organise and clip all this cable into? rather than clipping directly to joist? (needless, over the top?)

 

[Intoelectrics]

Anything that improves the install is a good thing. What you have to ascertain is whether the cost justifies the ends.
Reminds me years back when I did some sub-contracting work for another electrician. He only did domestic and very small commercial installs (shops and stuff) I had only ever mainly done industrial to this point so doing domestic was a novelty for me (at first). I was clipping a load of cables along the joists on the first floor. I made sure each cable was dead straight and the clips all lined up nicely so it looked very neat.
Later the guy I was doing the job for called in to see how I was progressing. He noticed the cable runs I had clipped and commented "F*** sake that's a neat job, the mice will be well impressed"

 

[Wilko]

Access and current rating are not helped by burying the cables under a mountain of insulation in a loft. So if the cables were run in a tray it would be helpful, but in my experience no one will pay for it.

 

[Stephen Paul Jones]

Thanks guys, I will use the trays, so much neater and the insulation can run under them, reducing rating problems as mentioned, going to order some from TLC today, if you know of a cheaper supplier, please let me know.

 

[Stephen Paul Jones]

Is it from a feasible and regs point of view ok to put the 45amp cooker isolation switch and a number of FSU's (to a number of appliances from the kitchen) in a cupboard in the utility room 10-15 feet away? Other than fuse protection, these switches are for maintenance only and will be easily accessed.

 

[telectrix]

isolation switches should be in close proximity to the appliances. scenario could be a chip pan fire. you can't get close to the hob to turn off: accessible isolation switch within a couple of yards is advisable. then get the wet towels on the job. N.B. if the hob is gas, the above is irrelevant. (apart from the wet towels).

 

[Intoelectrics]

isolation switches should be in close proximity to the appliances. scenario could be a chip pan fire. you can't get close to the hob to turn off: accessible isolation switch within a couple of yards is advisable. then get the wet towels on the job. N.B. if the hob is gas, the above is irrelevant. (apart from the wet towels).

Unless some idiot put the isolation switch in too close proximity in which case you'd get burnt before you could isolate.

 

[telectrix]

if it's too close, it would be melted and unswitchable, maybe a case for a regs.amendment. cooker isolators must be metal.

 

[Stephen Paul Jones]

interesting comments, the regs even for you qualified Sparks can be interpreted slightly differently, so are these switches for isolation (cooker switch, eg maintenance) or clearly for an emergency, therefore must be reasonably close to the appliance? is there a given distance in the regs?

 

[Octopus]

Thanks guys, I will use the trays, so much neater and the insulation can run under them, reducing rating problems as mentioned, going to order some from TLC today, if you know of a cheaper supplier, please let me know.

What does your spark say about all this?

 

[Octopus]

Thanks guys, I will use the trays, so much neater and the insulation can run under them, reducing rating problems as mentioned, going to order some from TLC today, if you know of a cheaper supplier, please let me know.

What does your spark say about all this?

 

[Stephen Paul Jones]

Have not hired a Spark yet, but the reason for this me joining this forum was to engage with a huge range of Spark's, like yourself, to get an impartial and broad view regarding my questions and concerns, also to gain additional ideas, rather than rely on the "one" hired spark to suggest the design of my electrical layout, which could be constrained due to his ability or limited views. Sensible in my mind... and I have received really constructive feedback so far, which is appreciated.

 

[remedial]

Its seems unlikely that you have any intention of hiring an electrician. But the point of this forum isnt really to enable homeowners to do their own electrical work (which, in your case is probably notifiable).

I suggest you hire an electrician to design your circuits for you. If you want to share the design on here you will get plenty of feedback on it. Alternatively you could buy the books and figure it all out for yourself.

 

[Stephen Paul Jones]

I am sorry to have to say this.... but there is always the one, on any Forum!!! Trainee Access, It's amazing, how long have you this sixth sense?..... knowing what I am planning, you should be on stage, waisted as a Spark. I have come on here as I have an interest in the subject and to discuss my thoughts and to get a general view before I take on a Spark, a little bit of info for you, I chatted to David last night and David is an electrician from Ponty, but I thought you would have known this and... he is calling me on Monday evening. Clue in my previous thread "not hired one yet"... assumptions!