The move raises fears that similar pay cuts could be considered in the UK.
Irish employers are pleading with the unions to accept the drop in a bid to save jobs in the wake of the deepening recession in the industry.
The call comes as the Construction Industry Federation - which represents more than 3,000 contractors - unanimously rejected a national pay settlement.
The deal was originally agreed in September and gives workers increaseses of 6% to 6.5% over 21 months. The agreement covers the Republic as a whole and has been accepted by other private sector employers.ADVERTISEMENT
But the construction employers now want the increase to be replaced with a pay cut as the industry dives.
Federation director general Tom Parlon said the proposed 2009 pay deal ignored the current state of the Irish economy.
He forecast that construction employment will drop to 190,000 - down by 90,000 compared with the end of last year.
He said: "Jobs are being lost and construction firms are now tendering at 8% to 10% below the cost of particular projects. Executives within building companies are being laid off or taking substantial pay cuts."
The Irish unions - which include Ucatt and Unite - will fight the move vigorously.
Parlon said: "The bottom line is that the industry can't afford the deal and is seeking a 10% reduction to safeguard jobs in construction. A 6% increase was never realistic at this time."
Talks have now been referred to the Irish TUC's construction committee. Failing an agreement, the employers' claim may be referred to the Labour Court.
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