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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[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

 

[markyrp]

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

Daz,

I had thought of that but I would have to see his record of test results. I wasn't asked anything about my current system. What I had connected etc.

Maybe he just routinely carries out IR by connecting Line and Neutral together.

 

[DPG]

Maybe so yes. It would explain it. Daz

 

[Octopus]

Daz,

I had thought of that but I would have to see his record of test results. I wasn't asked anything about my current system. What I had connected etc.

Maybe he just routinely carries out IR by connecting Line and Neutral together.

Which IMHO isn't really acceptable when doing new/additional work on a circuit.

It all sounds like a bodge on the cheap!