Figures seen by RTÉ News show that 15 major works completed by the Department of Education and several hospital redevelopments have cost more than their original budget since 2010.
This new information about capital projects that cost in excess of €10 million has been released to Fianna Fáil's Finance Spokesperson Michael McGrath.
The average difference between the initial tender contract and the final cost was 6%.
The Minister FOR Education said the Department carefully manages and controls costs on all projects to ensure the best possible outcome.
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The biggest single one was the redevelopment of St Luke's Hospital in Kilkenny which was first estimated to cost €13.1 million but the final figure was €20.1 million.
The difference was explained by items added after the signing of the contract.
An upgrade of Galway University Hospital also cost €2.5 million more than the first tender price.
Time delays and contaminated soil were among the reasons listed for the increase.
Cost overruns have sparked much political controversy recently given the €450 million extra required to build the National Children's Hospital.
Deputy McGrath said the National Children's’ Hospital costs were extraordinary in scale but there is a pattern of projects running over budget.
He has passed on this latest information to the State's spending watchdog the Comptroller and Auditor General.
The Cork South-Central TD is also demanding a review of how major capital projects are delivered.
Meanwhile, a Government spokesperson said that the three biggest capital projects of recent years came in on time and within budget.
They said this includes: the LUAS cross city project, the M11 and the Gort to Tuam motorway.
The days of the majority of projects running over time and budget are long gone, they said.