M&E firm Haden Young was accused of deliberately setting out to bust one of its subcontractors on the Exeter Schools PFI project at an employment tribunal last week.
The allegations were raised by former Haden Young manager Alan Wainwright, who has brought a claim of unfair dismissal against the company.
His claims centre on a previously dormant company, Bromsgrove-based DUSC Electrical, which he says was awarded over £1 million-worth of M&E work on the project by Haden Young's southern operations manager, Eamonn Dunne.
DUSC Electrical went into liquidation in February 2006 with debts of £1.1 m illion.
But Mr Wainwright's witness statement describes how another subcontractor on the Exeter scheme, Sean O'Connor, of High Spec Comms Civils, came forward after being left £180,000 out of pocket by the collapse of DUSC.
He said: 'Mr O'Connor informed me that it was his belief that Haden Young had deliberately set out to bust DUSC to boost Haden Young's financial position on the project.
'Mr O'Connor explained that he had learned that Eamonn Dunne had originally awarded the initial subcontract package of work to the dormant company as the company employed a long-standing friend of Mr Dunne's, Chris Lavery.'
Mr Lavery became a director of DUSC in February 2005. Mr Wainwright claimed that Eamonn Dunne's brother, Kevin, also went on to work for DUSC.
Mr Wainwright has also made allegations of blacklisting and fraud against Haden Young at the tribunal, which finished on Tuesday.
In his closing statement he said: 'Any compensation awarded by the tribunal will go nowhere to covering my true financial losses. I want the tribunal to know there was no financial motive for me raising these matters and my primary objective is to prove the abhorrent working practices of the company.'
Haden Young declined to comment.