The answer to this is simple. The contracting company is wrong.
Conservatories are not exempt.
Here is a second opinion.
tell them that unless they get this tested and give you a certificate that it’s compliant, then you will have no alternative but to get it tested and any remedial work done by a third party and you will charge them (and sue them through the Small Claims Court is necessary) for the cost.
You might want to print the article off and this page and asked them to explain that and where as you have shown them in writing that the conservatory is not exempt ask them to show you where it is shown that its exempt. They may struggle!
Incidentally, the conservatory may or may not require building regulations approval depending on all variety of different criteria but the electrical installation does
Can I clarify anything else for you?
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