Householders at a new Balbriggan housing estate have not received post since last Wednesday because of a dispute between the builder and the Building and Allied Trades Union.
In another dispute at Tallaght the new stadium for Shamrock Rovers is being held up in a dispute where the main contractor is threatening to have a BATU official committed for allegedly breaching a High Court order forbidding him to picket the site.
Both builders are members of the Construction Industry Federation and the disputes are the latest in a series of skirmishes between builders and BATU over the use of subcontractors.
In both cases the National Implementation Body has failed to bring the two sides together.