Extensions Question

Completion paperwork

Hi, we are nearing completion of an extension which has included new boiler and new electrical box (and electrical work in other areas of the house). We have been in close contact with building regulations and know we are required to get a completion certificate from the building inspector but could someone tell me please what other paperwork should we be expecting from the builder? i.e. guarantees etc. Also, I know that gas and electrical work needs to be certified, at risk of sounding completely stupid (I am pretty clueless with this!) is there standard paperwork used here or is it just a case of the plumber / electrician signing something or showing their qualifications and certificates to building regulations? Many thanks for any help

Thanks Simon, that was really helpful, but have one further question -From what he has said, our builder is planning to do the electrical work himself and have it certified by an electrician. I think this is ok as long as it is certified? but should the electrician be coming to check the work as it goes along (i.e. check connections etc that are under plasterboard) or can he cerify it by doing checks at the end (as previously said I am a bit clueless and just want to make sure everything's ok!). Also, when the electrician and plumber put their registration numbers on building regs paperwork, is it then building regs responsibility to check this or ours? Thanks again for info..

3 Answers

Best Answer

The boiler will have an installation and commission certificate in the installation instruction package, to be completed and registered by a GAS SAFE REGISTERED Engineer. The Electrician will have a separate book that he will Complete upon completion and provide you with a copy. This cannot be done prior to completion in case a cable/fitting is damaged during the works. Appliance Guarantees are normally placed in a Kitchen Draw at completion, but speak to your builder! Any Insurance Baked Guarantee Works- Certificates will be provided (normally shortly after completion) And Building control will require a visit at/shortly after completion, their certificate will follow (normally within 2weeks. The plumber/electrician have to put their registration No.s on the relevant forms.
The previous Government tried to implement a standard home sellers package so that everyone did the same thing...but it never really took off.

I hope this is of assistance

Regards Simon

Hello Peggy,

It should not be a problem for your builder to do this, I often do the same myself.There SHOULD not be any connections under plasterboard, except maybe, extending existing supplies, however the electricians tests will show anything amiss! He will not need to check as work goes along. He will remove sockets etc. to check at the end. Modern test devices show most problems just by plugging the in.
It is the responsibility of the registering body to check relevant qualifications etc, not yours or building control. Your details go on the installation forms, and they will be in touch if anything is wrong!

Answered 26th Aug 2011


Member since 19 Jul 2011

very common this, theoretically he can sign it off without having seen or touched it, however this then means that he is responsible for all the wiring rather then the builder.

As long as the builder knows the regulations then you will not have any problems.

Chances are that the electrician knows that the builder knows what he is doing.
And thats why he is willing to sign work off for him.

Legally there is no clear yes or no, (I believe) as long as it is done by a competent person, and the building control is informed, either by a qualified electrician or via the building control coming round.

Answered 29th Aug 2011

Union Plumbing and Heating

Member since 30 Oct 2010

The electrical side of your question the work should be carried out by a registered Electrician the builder is not allowed legally to do this work himself if he is not a registered Domestic installer unless it is inspected in compliance with the British Standards BS7671
The testing inspecting(visual at first fix) and recording of the results before the system is energised made live is essential then another series of testing is carried out after being made live this is all recorded on an installation certificate and a full copy usually at least 3-5 pages should be left for the owner.

Registered Electricians cannot sign an installation certificate for someone else if they did not install the work themselves this is dishonest!

A report on the condition of the electrical system can be issued and this can be accepted by the building inspector if he chooses to do so.

Your builder is just trying to save himself money if he does work he is legally not qualified to do, if he thinks he is clever enough to carry out electrical works then he should prove it and get inspected by the NICEIC or similar the fact is it would cost him thousands of pounds to do that! The proper test equipment costs from £800 - £1500 pounds, learning how to use it far more, registering as a domestic installer £400+ every year. That's why electricians are not cheap and builders try and do it themselves.
You can check that an electrician is registered as a domestic installer go to this site it also explains why he should be ' Building control'


or ask him which body he is registered with look up their website and check

Answered 3rd Sep 2011


Member since 9 Oct 2008

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