UCATT general secretary George Brumwell told delegates at the Labour Party conference that if they voted for a motion for an independent review of the PFI, put forward by the public sector union Unison, it would lead to a halt in projects and threaten the health of the industry.
Delegates, however, ignored Brumwell, as well as prime minister Tony Blair and chancellor Gordon Brown, and voted 2-1 for the motion.
The government made it clear before the vote that it would not introduce a review or a moratorium on PFI projects irrespective of its outcome, saying the public would not tolerate delays to hospital developments.
Brumwell, who made his contribution during the PFI debate on Monday, said: "A moratorium would send shockwaves through the industry and hit thousands of workers. The industry is going through a massive boom while the rest of the European market is in the doldrums. That is because of PFI."
Brumwell said delegates should not deceive themselves into thinking that the pre-PFI procurement era represented a golden age. He said: "If anyone thinks it was only when PFI was around that taxpayers were ripped off, think again; taxpayers have been ripped off for 50 years.
"Contractors walked away from jobs leaving the maintenance costs of buildings behind them – 30 years later they had to pull the building down because they were crap. That's the reality."
He added that the PFI environment had changed in the past year.
A moratorium would send shockwaves through the industry and hit thousands of workers
UCATT leader George Brumwell
"Twelve months ago, the industry saw PFI as a gravy train; 12 months later, that has changed. That's because Gordon Brown is putting the screws on them and making them accountable and making them perform."
Brumwell told delegates that he would support the PFI as long as contracts included decent terms and conditions for construction and maintenance workers.
GMB general secretary John Edmonds, whose union has many members in construction, launched a strong attack on the PFI during the debate.
He claimed that the private sector was making excessive profits from the PFI and said: "Money paid to contractors should be going on services, not into the pockets of City institutions."
He added that the PFI led to cost overruns and poor service.
Blair and Brown rejected calls to review the PFI or to introduce a moratorium.