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[dzzr1brown@aol.com]

Sorry about this but yet another garage wiring question.
I'm having a concrete sectional garage covering 48 sq. m. erected seperate from the main building and have already found that i need 6mm swa cable. I intend to supply this from a second CU with RCD protection and a 32mcb running to a standard CU in the garage with 6 and 20 mcb's for lighting and power.
Question:- Do I need to use RCB protected sockets for every power outlet in the garage or will the one at the supply suffice and is there a minimum height for the CU in the garage. I Intend to line the garage out with board so presume that surface mounting and ducting all cables is the safest option along with running as much cable at high level as possible.
Please be aware that i am competent but not having the required certifications I know I have to have the whole lot checked by a listed Sparks.
Many Thanks
dave

[sparx]

Hi,
you don't have to have it 'checked' by a part P registered 'sparkie';
he must do the work,
it is not permissable to sign off work not done personally!

Only exception is if you pay fee to Local Authority Building Control before starting any work, they will use some of the fee to send around an approved electrical inspector at first fix and second fix stages.

One source RCD will suffice!
Consumer unit must be 'readily accessible' without needing steps.

Surface 'mini-trunking' good option.
regards

[ericmark]

“Question:- Do I need to use RCB protected sockets for every power outlet in the garage or will the one at the supply suffice.”

If the RCD in the house is 30ma at 40ms then no. However it the RCD in the house is larger in ma rating or slower in time then you will need extra RCD to lower the leakage allowed to 30ma max.

Is there a minimum height for the CU in the garage.

I states it must be where it can't be damaged and anyone working on any electric board should be able to step back from the board. However often this is not complied with and to protect the board handrails are fitted which in turn stop one stepping back. This needs to be considered by who ever is signing for the work and it is his call and you must ask his advice is doing anything out of the ordinary.

I Intend to line the garage out with board so presume that surface mounting and ducting all cables is the safest option along with running as much cable at high level as possible.

Anything covered will need to comply with buried cables rules.

Please be aware that I am competent but not having the required certifications I know I have to have the whole lot checked by a listed Sparks.

If you are competent that is above being skilled then there is no reason why you should not fill in your own paperwork, in fact it is a requirement that you do fill in the installation certificate. However the completion certificate can only be issued by the scheme operator or the LABC no spark can fill in these.

The installation certificate has provision for three signatures and it is common to have one highly skilled guy doing inspection and testing and lower skills doing the work but only the larger firms have arrangements with the scheme operator to allow multi signatures. One man bands normally have to do everything themselves.

Using a one man band and multi signatures normally means going through LABC which if a new garage likely you are anyway.

Of course you will have to have included electrical work on the original request and if you have then the need for an electrician to inspect is a grey area. The council will inspect and test but they will not issue an inspection and test certificate only a completion certificate. This may seem daft but the Part P is to BS7671:2001 and all scheme operators need it to comply with BS7671:2008 so a installation which fails today's regulations could still pass with LABC and get a completion certificate.

Competent person. A person who possesses sufficient technical knowledge, relevant practical skills and experience for the nature of the electrical work undertaken and is able at all times to prevent danger and, where appropriate, injury to him/herself and others.

Skilled person. A person with technical knowledge or sufficient experience to enable him/her to avoid dangers which electricity may create.

Do be careful calling yourself competent as if you are the LABC can and will ask you for installation certificate as you are saying you can complete it. I would consider some one holding a C&G 2392 or better (2391) as competent and those with just C&G 2382 as skilled. But that's not what the big red book says.

[dzzr1brown@aol.com]

Hi guys, thanks for the info, just getting to grips with the new regs, i did HNC elect and mech in my earlier years and spent nearly 40 years as a shift engineer in power stations, however i am aware this does not make me skilled but i do know how to do a safe installation. unfortunately these days as you rightly say, that isnt enough. My cable is buried to 450mm and i have the tape to cover it. My book on the regs says that there is no set depth in the regs but you have to take account of the ground and its foreable use, eg possibility of double digging etc.
again many thanks
dave

[ericmark]

With your qualifications you could you your own testing and inspection and the forms are on the IET website.

[austin24]

Thats very true, i have completed the 17th Edition training never completed the part P yet as my trade changed slightly however had a fully qualified sparky fit a new outside light while I was training and he visited twice as it did not work correctly to me 15 minutes to solve the fault as wires were all back to front, hence that firm is no longer in buisness. So if the fully registed guys cant solve a simple fault why do u need so many regs

[TheDoctor4]

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