Since the 1st January 2005 it has been a requirement that certain domestic electrical work must be carried out by a competent electrician.
Some items of electrical work such as changing sockets and switches or installing a new light fitting to existing wiring can be done by the householder but in the main a qualified electrician must be employed.
With this in mind, the following links will enable you to check whether your chosen electrician is registered with a competent persons scheme.
If in doubt please contact Building Control on 01772 625400
Find a registered electrician - A register of electricians belonging to the various CPS schemes www.electricalcompetentperson.co.uk/
General guidance - For general advice, guidance and information in easy to understand formats https://www.electricalsafetyfirst.org.uk/guidance/