THE new National Children's Hospital will not be ready until the end 2018.
It is understood that the project is six months behind the schedule set by Health Minister James Reilly.
Medical services will not be transferred to the new hospital until late 2018, despite Dr Reilly saying in September that it would be ready to open in the spring of that year.
The long-awaited facility is needed to provide modern care for thousands of sick children across the country and was originally supposed to be ready in 2012.
Details of how the hospital, expected to cost €600m, will be delivered are contained in a presentation for companies given at an open day in the office of legal firm Arthur Cox in Dublin.
It was made by chairman of the hospital board Tom Costello, chief executive Eilish Hardiman and senior HSE building officials on Monday.
The new hospital will merge the three existing outdated and structurally inferior children's hospitals in Crumlin, Temple Street and Tallaght in Dublin.
The documents have revealed that a number of milestones needed to plan and deliver the hospital have now been put back.
A design team was due to be appointed for the new building in October this year.
This has been pushed back to March next year.
Also, the board does not now expect to secure planning permission through a fast-track process from An Bord Pleanala until the spring of 2015.