Report by watchdog is highly critical
While the Public Accounts Committee report examined seven major arts projects, its most serious criticism centred on the Lyric Theatre.
The Lyric was built in 1968 but by the 1990s it breached health and safety legislation and was in need of urgent repair.
The rebuild was originally estimated to cost £12.4m, however the final cost soared by 42.4% to £17.8m. In total, the Department for Culture, Arts and Leisure provided £12.2m to the project.
The PAC's criticism focuses on the £11m contract awarded to builder Gilbert Ash in 2008.
Although the PAC did not find fault with the company, it criticises DCAL, the Arts Council and the Department of Finance's Central Procurement Directorate.
It details "completely unacceptable departures" from good practice, including:
* Unexplained adjustments to the tender submissions.
* A £413,000 bill paid in full even though it had been stripped out from one of the tenders.
* Documents showing how the bids were evaluated and adjusted were destroyed.
* The sponsoring bodies (the Department of Culture, Arts and Leisure and the Arts Council) failed to attend the tender evaluation meeting.
* The preferred bidder, Gilbert Ash, provided a donation of £150,000 to the Lyric.