I am sure you are more than capable to do the work but it is evident that many organisations are taking the view that electrical installation work should only be undertaken by competent electricians with the appropriate formal qualifications to prove such. That basic qualification is the NVQ Level 3 + AM2.

Doing a wiring regulation course or an inspection and testing course would be beneficial but would not formally accredit competence, irrespective of your experience. So for example, having a degree in electrical engineering is neither here nor there in one of the biggest telecom companies in the UK. If the operative does not have a NVQ L3, then even minor electrical installation work would not be permitted.

Maybe its all mad, but facilitating a route for experienced electricians without formal qualifications pays a fair chunk of my grocery bill!

Further to Lyle's response; for your awareness and to expand your own knowledge base of BS7671 there are typically college organised courses for the 18th Edition IET Wiring Regulations (City & Guilds 2382-22) - the course can be delivered at nights or weekends (overall duration 20-24 hours). Outcome of training will require you to complete a short open book multiple choice exam. Upon conclusion of the training and exam you'll receive the 18th Edition certificate. The course itself costs circa £550 and extremely beneficial - dependent on the course organiser, you should receive plenty of reading material and support. 

Thanks for the responses. We, as an organisation, ask that contractors have the C&G 2382 qualification. Recent experience has taught me that I would only employ apprentice-trained people into roles like this and the jokes about the two week wonders etc is all making a bit more sense. 

There is no way I'm doing an NVQ, I'd never be able to justify it for my job. I do think taking the 2382 course would be beneficial, and I would be able to justify it. It is a start either way.