More than 500 rank-and-file sparks voted to take part in unofficial action during a stormy meeting in London last week.

The workers are furious that major employers in the M&E sector are quitting the JIB agreement which has historically set pay rates.

Eight major contractors will quit the JIB in March 2012. They are Bailey Building Services, Balfour Beatty Engineering Services, T. Clarke, Crown House Technologies, Gratte Brothers., MJN Colston, SES and SPIE Matthew Hall.

The move has sparked outrage among electricians who claim it could lead to pay cuts of up to 35% and a “de-skilling” of the industry as new grades are introduced.

The London meeting was the first of a series planned countrywide as the electricians organise under the banner of the rank and file Site Worker magazine.

A spokesman said: “The assembled electricians and pipefitters sent a clear message that they will not accept the de-skilling of their trade or the pay cuts to their national agreements.

“The last time the electrical contractors attempted to cut wages by de-skilling the electrical trade in 1999 it provoked a series of wildcat strikes on the Jubilee Line, Royal Opera House, Pfizers and power generation projects across the UK.”

The electricians now want to see the Unite union ballot members working for JIB firms who have been told that their terms and conditions will be changing next March.

A committee was elected to oversee unofficial strike action.

The spokesman said: “This new movement is on a high and we can spread the mood around the country and throughout construction.

“There will be attacks on other trades too we should try and build things involving Ucatt and GMB members as well.”

Unite is calling on its members to organise on sight to fight the changes and officials will meet with the major contractors on August 23 to discuss the situation.

The pull-out by the eight majors has also stunned the ECA trade body.

JIB chief executive Steve Brawley said: “The proposed agreement is currently being created outside the JIB National Agreement and without the support or backing of the ECA or Unite the Union.

“Consequently, the existing JIB Agreement, in its entirety, will continue to apply to JIB member companies and their operatives representing, as it does, the longstanding partnership between the ECA and Unite the Union.”