Organisers of the demos are planning events in Newcastle and Manchester tomorrow targeting sites run by Crown House, Balfour Beatty and NG Bailey.
A protest will also be held outside the Shard in London as rank-and-file workers voice their opposition to plans by employers to pull out of the JIB.
A campaign spokesman said: “The Shard was chosen even though we are having difficulty identifying the electrical contractor because most workers are with one of the 10 or so agencies for mechanical and pipe fitters.”
Protests have already been held at Blackfriars Station and Westfield shopping centre in Westfield.
To watch a video of these events click here