shocking workmanship?? wired up a dangerous socket in the loft and joined wires with tape

If he is genuinely registered with the NICEIC, (it should state his registration number on the certificate in the bottom left hand corner of page 1), then you have full redress through the NICEIC complaints procedure. They will investigate your concerns and get the work put right FREE of charge. However its fairly common to find Non-Competent people who claim to be NICEIC registered and are not and they issue fake/stolen certificates. Best advise is photograph everything and record all conversations, what is said, time/date etc as its all useful evidence. Look for the NICEIC registration number and start from there. Heres a useful link to the NICEIC complaint procedure from their website: http://www.niceic.com/Uploads/File1256.pdf

Report the engineer to NICEIC, they will visit property and enforce him to rectify the work or remove his trading licence

i cannot believe a NICEIC contractor would do this but until i had vied his certificate or give me his details and i can pull up his credentials on the NICEIC web site as you can do? you should now before engaging any contractor sign a contract agreement intailing all works explaining your rights and the schedule of works to be carried out and the 14 day cooling off period. this is now law under the consumer act agreement and its a MUST!!! by all contractors no matter what trade they are i mean everyone and they produce their liability Insurance ?