Members of the AEEU and the MSF unions have voted overwhelmingly in favour of a merger.
A secret postal ballot has endorsed plans to create a super union with over one million members.
The new union will be the second largest in the TUC and will have assets of over £100 million and an annual income above £60 million.
Sir Ken Jackson, AEEU general secretary, said: "This will be the UK's strongest union, with the strength to back our members at work. We'll have the resources to set the agenda across every sector of the UK economy."
Source
Electrical and Mechanical Contractor