The issue of the height of the room designated to accommodate a new printing press for the Oireachtas "never came up" when the business case was being examined, the clerk of the Dáil has told the Public Accounts Committee (PAC).
Peter Finnegan has told the committee that mistakes were made, but he put them down to "human error" and said the decision to buy the computer was the correct one.
In response to questions from Social Democrats TD Catherine Murphy, he said the "first and fundamental mistake" was the absence of architectural input on the evaluation team.
"If we had an architectural input on the evaluation team the issue of head height would have been identified right at the very start. That in turn would have had an impact on the business case," he said.
He said the Business and Strategy Committee, which is made up of a number of senior civil servants, did not sense any issue in relation to the height of the room when they examined the business case.
"Three or four members of that committee went over to that unit, went in to the rooms where the printer was going to be installed and the issue of height never actually came up. There was no sense at all that height was an issue," he said.
"The perspective was that the project involved the purchase of an asset, the complexities around the installation of that asset were not considered at all," he said.
He said another big mistake was that a note in the original tender from the manufacturer of the printer, Komori, raising issues around head height was missed.
"The evidence I got was that they actually missed the statement on the bottom of the page which said the head height was limited," Mr Finnegan said.
PAC chairman Sean Fleming said the costs provided to the committee have risen by 73%, from €1.169m to €2.02m, since Mr Finnegan appeared before the committee in July.
Mr Finnegan submitted a further report on the cost of the printing press to the PAC yesterday, which showed that the total cost has reached €1.8 million, €200,000 higher than the €1.6 million outlined by the Oireachtas just two weeks ago.
Mr Finnegan said the debacle has ended up costing the Oireachtas €112,000 more than it should.
He said: "€112,000 is an awful lot of money. It really is. I understand why people would be very, very annoyed over that."
He was replying to a question from Fianna Fáil's Liam Aylward.
Mr Finnegan told Fine Gael TD Kate O'Connell that the core of the problem was the team overseeing the project ".didn't have the skill set for what they wanted to do".
He also said the Oireachtas authorities did not investigate a leasing option for the printing press, only a purchase option.
Mr Fleming backed the purchase plan by saying: "It's important we have those facilities in-house."
The committee also heard that the printer weighs 17 tonnes.
