Midwest, I have replied to your post with a link to the type of led they are. I don't know what you mean by how they are switched ( not on a dimmer if that's what you mean ) . Also I am trying to reply by quoting in responses but when I do I can't see the option of posting the reply so have to just reply at the end of the posts.
@anthonybragg the light fittings themselves aren't covered with insulation ( I guess you mean fire rated covers by that ) . The wiring is simply fed into connector blocks from ceilings and the led have a brown and blue wire only which have been connected to the block also.
@alisdairp - thanks for that. The EIC cert does have the certifier 6 digit ID number and name and address so I will be seeing him in the new year and questioning why its been signed off as fine when its actually tripping . I won't put a higher amp in that's for sure.
The electrician himself works for a company and was recommended by a colleague at work so I went with him purely on recommendation.
In meantime I will turn off CU power and check every light switch and light to see if there's any loose wire on ground floor and if it all looks fine then it may be a frayed wire somewhere in between the joists (I did point 3 out before everything was boarded up ) which were replaced but now I feel there maybe others .
Also he tacked in the wires against the wall in a couple places using nails which were then bent over the wires to hold them in place but I did check and they were loose enough just to hold the wires in place so not cutting into any wires.
Just remembered the above now so hoping these aren't the cause too.
I wasn't there most of the time as was at work so he has made me very concerned now .
If theirs no joy just after the New Year I will simply report him to his workplace , Building control, NIC, and also the tester will be reported and will see how far that takes me , otherwise more costs to correct this will be a harsh lesson learnt.
All the best to you All and a Happy New Year in advance if I don't get back til Wednesday now.
Thankyou to each and every one of you for your input.