Extension and Garage Conversion Wiring

[markyrp]

Hi All,

I was hoping to get some advice on some building work which is currently ongoing at my home. I am having a single story extension added to my current kitchen/diner. I am also having my garage converted and some power ran to a new shed which has been recently built.

The builder has been great but electrical work has been subcontracted out to I believe an electrician he uses regularly. The electrician has extended the existing downstairs ring final cct to include an additional 4 double sockets in the extension and 3 double sockets in the garage conversion. The downstairs lighting cct has been extended to include a single light fitting in the extension and 4 downlighters in the garage. I had also requested power to the shed which he has done by running swa cable from one of the garage double sockets which then feeds 3 double sockets (wired as a ring cct) and a single light fitting, all from a single switched fcu. He also ran some coax and cat5e cable for me whilst the building work was going on.


I have numerous concerns over the work. I am an electrical engineer by trade but I am not an electrician and therefore don't want to tell an electrician how to do his job. The number and position of electrical fixtures and fittings were all discussed prior to the commencement of work and the guy has been very accommodating but I have not been impressed with the quality of his work and like I say, I have concerns over whether or not some of it even complies with current regs.

The house was built in 2005 and so has RCD protection for both up and downstairs ring final ccts but no RCD protection for the lighting ccts. From my observations, the relevant ccts where isolated at the CU (isolated as in main switch off) when the additional fixtures and fittings were connected and the testing only started after the ccts were made live. My confidence dipped immediately after he made the ccts live because I heard a sort of 'poof' sound and either an mcb or the rcd tripped. Not sure which but he immediately reset the breaker/rcd and no further problems. When I asked him what had happened he replied 'just the system clearing itself'. An answer that left me stunned.

I don't know what testing he did exactly but I have fixed appliances connected in my kitchen, i.e. cooker, fridge etc. and nothing was disconnected, no light bulbs were removed from the existing downstairs lighting cct and I don't know if he even took the front cover off the CU prior to testing. I did see him writing the results of his 'testing' in the relevant paperwork.

I also asked for my alarm system to be modified to include an additional PIR to protect the area of the extension. He kept blowing fuses in my alarm control panel after trying to daisy chain this additional PIR from the existing kitchen PIR. He drafted in his son to help which resulted in his son frying my alarm control panel which now has to replaced.

The electrician is a really nice guy and appeared to be very accommodating. I have cut him some slack because he is a nice guy and a bit 'oldschool' but not at the potential expense of the safety of my home and family.

Any comments on compliance with regs etc would be greatly appreciated. He is due to come back to replace my alarm control panel but I am unsure whether or not to allow him to continue. I had agreed to pay for any additional work (shed wiring and av cable runs) direct to the electrician and the builder says that the electrician hasn't billed him yet.

Mark

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[Bobster]

I am an electrical engineer by trade but I am not an electrician and therefore don't want to tell an electrician how to do his job.

Care to expand on what you mean by electrical engineer? As being an engineer your knowledge should be far more than the electricians and in fact you should be able to tell him what you want.

 

[J.C.E]

How has the addition to the lighting circuit been installed?

 

[DuaneMHunt1976]

I dont understand this Post, you have 2391 so you know all the testing that is needed.
Also done 17th Edition plus you have "Domestic Installer" as your qualification!

guessing you know also how to check someone with the Governing Bodies or their Qualifications.
If they are not with a Governing body and just do Minor Work so avoid it (what adding to the RING and the Lighting Circuits seems to suggest, Personally i would put the Shed on its own MCB! but that would mean a NEW CIRCUIT and EIC)

 

[markyrp]

I dont understand this Post, you have 2391 so you know all the testing that is needed.
Also done 17th Edition plus you have "Domestic Installer" as your qualification!

guessing you know also how to check someone with the Governing Bodies or their Qualifications.
If they are not with a Governing body and just do Minor Work so avoid it (what adding to the RING and the Lighting Circuits seems to suggest, Personally i would put the Shed on its own MCB! but that would mean a NEW CIRCUIT and EIC)

Just to clarify. I was an Aircraft Electrical Engineer in the Armed Forces and I when I left the forces, as part of my resettlement entitlement I chose to do some courses including a 'Domestic Installer' course, 17th Edition and 2391. I chose not to pursue this any further when I left and went in another direction.

I live in Scotland and the electrician is a member of SELECT.

With respect to the lighting circuit, for the extension he used the existing wiring which was for an outside light and extended the cct into the extension. For the garage conversion he simply modified the existing lighting cct and installed 4 downlighters.

I haven't seen the record of test results so I am not entirely sure what tests were carried out or how he has documented the work he has done. As I say, the work is not complete yet and the electrician has all the necessary bits of paper.

I was merely asking for some comments from people more experienced than myself in this area.

 

[malcolmsanford]

To be honest Mark there seems to be several issues here. The design of the outbuilding circuit at best is quite basic at worst poor.

• First there is the obvious what certification was issued for the electrical work? Sometimes Part P is incorporated within the notification of the extension work, but he would still need to issue the very least MEIWC certifcate for the work he did
• The "poof" would have been a fault on his work. Could have been a trapped cable, or reverse polarity which he most likely corrected. If there were still a fault the protection device would not have reset.
• The lights extension, there may have been a need for him to provide RCD protection for the cable he installed. Depending on his method of installation. This is something you need to ask him.
• Though technically what he has done with extending the ring out to shed is acceptable on a spur, it isn't the best design to be honest.
• Can't understand why he has wired a ring circuit off that spur, for just 3 sockets.
• Also it is again poor design that the sockets and the lights are off of one spur. Though technically it is allowed it is poor design

 

[Octopus]

We're you given any certificates for the modified circuits? There should be 1 cert per changed circuit.

 

[DuaneMHunt1976]

Can you do a IR test just on the Cables you are Hooking up.
IE just crock clipping to the cables going off to the New Lighting/Sockets and do a IR test just on them cables before hooking them on.

and the also needs to do a RCD test really to make sure the new part is working correctly so it should go off a few times .

 

[markyrp]

Malcolm,

Thanks for the reply. My thoughts are pretty much the same as your comments.

I think he is going to certify the work on a Minor Works Certificate. The lack of RCD protection on the lighting circuit is a non compliance in my opinion anyway.

With respect to shed wiring, he had left his assistant to get on with the work. His assistant had ran the cable as a ring cct and the electrician just went with it as the cable was already clipped into position. Just clipped T&E, no conduit or anything. Just poor in my opinion.

The builder has already rectified an issue with how the SWA was routed out of what was the garage, into the shed.

With respect to testing, as I said I don't know what exactly he did but I can remember him testing the rcd.

 

[Gazthesparky]

Part P doesn't apply in Scotland. Even so he needs to supply test certificates for any work or alterations he has done..

The poof you heard was likely a fault blowing clear which is a rough and dangerous way of working. You need to perform dead tests first before livening up the new circuits.

Clipping twin and earth in a shed is okish my opinion it's rough and a no no but technically if it's all clipped securely it's ok. I certainly wouldn't and would want conduit to provide better mechanical protection

As for blowing the circuit board on your alarm he is clearly out of his deapth with that to have fried the panel and having to bring his son in.

Where about in Scotland are you?

If you are close and would like a second opinion let me know and we can get something arranged

 

[markyrp]

Gaz,

Thanks for the response. I need to speak to both the builder and the sparky and give them a chance to address my concerns.

I suppose I was just looking for the thoughts of others as I am not happy with the work so far. I may well take you up on the offer of a 2nd opinion. I am in Irvine by the way.

 

[SS-2015]

I have personally fitted supplies to small sheds/outbuildings from downstairs ring (if CU is a pain to get to and customer doesn't need a large supply) but I have always fitted it via 13a FCU and Double pole isolator - at least this way if you have any faults outside you can isolated the external wiring and restore power to your ground floor ring.

As already said, the 'poof' would have definitely been a fault somewhere, which he would have found if he did IR check before energising.

As for compliance - it's a bit hard to judge without seeing it. I wonder if he has any cable calcs?

 

[Octopus]

Have you been given ANY paperwork regarding the electrical work?

 

[markyrp]

Have you been given ANY paperwork regarding the electrical work?

No paperwork as yet. The building work isn't complete.

As for previous post referring to cable calc's, I would be pretty confident in saying that no cable calc's were carried out.

No means of isolating shed power other than house CU. Just checked and FCU is only for the light.

 

[SS-2015]

So it sounds like the shed is spurred from the house? Unless he's extended ring down to shed?
How far is shed from House?

 

[markyrp]

So it sounds like the shed is spurred from the house? Unless he's extended ring down to shed?
How far is shed from House?

Yes. the shed is spurred off the house ring main. SWA is spurred off a house socket and into the shed which is only about 1.5m away from the house. The SWA is wired into a double socket within the shed. This double socket is connected to a further 2 double sockets wired as a ring cct. A switched FCU with a 13A fuse is then spurred of the first double socket for the light.

The electrician has stated that the lighting cct in the house doesn't require an RCD because he hasn't touched the wiring back to the CU. I can't get my head around this explanation. He has moved the position of a light switch and added additional wiring for light fittings and fixtures. Cable isn't buried more than 50mm below the surface either. I am not sure what the extension is classed as because it is an addition to an existing kitchen/diner. The area is now an L shape open plan and I'm not sure if the whole area is classed as part of the kitchen.

I'm not sure what testing he did but I am puzzled as to how he did his IR testing. I have integrated appliances fitted in my kitchen, none of which were disconnected, nothing was unplugged, no light bulbs removed etc. As previously mentioned, when he made the cct's live for the first time I heard a 'poof' and either an mcb or the rcd tripped. He immediately reset and there hasn't been any further incident but this initial trip and 'poof' sound has left me with a bad feeling.

 

[malcolmsanford]

Marky the spurred circuit for the shed does not comply. If the SWA was a 6 core!!!........... then he may have extended the ring out there. But I'm guessing it has spurred off the ring in a 3 core and into the socket. That is how it should have remained. By him then creating a ring off of the spur and then fitting a FCU off of the first socket for the light, smacks of incompetence really.

He should have fitted the FCU on the SWA and then taken your 3 sockets off of the load side of the FCU. Then really he should have fitted another FCU from the 3 sockets and fused down for the light

As for the non RCD for the light extension of the circuit. As soon as he burries that cable and does no conform to a mechanical way to protect that cable, that cable needs RCD protection. Regardless of it being an existing circuit.

 

[SS-2015]

The tripping would have almost definitely been a fault somewhere, although this would seem un-nerving and almost certainly proves he didn't test it correctly before energising, don't be to hung up on this as what ever was causing the trip can't be there now if he has re-energised system and it hasn't tripped again.

Although there is nothing majorly wrong with spuring a small shed from the ring it isn't best practice and I would certainly want it switched at least (double pole) even if he hasn't fused it down to 13a.

The way he has wired the light in the shed off of a FCU is a standard way of doing it, I would normally fuse that down to 3 or 5 amps - Not 13.

He is right about all the work he's done being extension/modification but in doing this his work must comply with current regs.
i.e Cable zones, RCD where necessary.

Back to the 'poof' sound again - was this on the ring or the lights? if lights is there any chance that it may have just been a bulb blowing?

 

[markyrp]

I'm not sure what tripped when he energised the cct. Could have been an mcb or an rcd. He didn't say but if it was a lighting mcb I don't think it was down to a bulb blowing. I don't have any bulbs out.

I personally don't think that some of the work is compliant. I don't want him to just fit an RCD because I have asked him to. I want to be confident that all of his work is up to scratch. I don't have that confidence at the moment. I am still wondering how he did his IR testing. No appliances were disconnected from the downstairs ring cct and no bulbs or anything were removed from the downstairs lighting cct.

 

[DPG]

Maybe he IR tested L-N to earth at 240V? Daz