Treasury plans to make contractors the single point of contact on major projects will lead to poor-quality buildings, consultants warned this week.

Consultants stand to lose their traditional role as the client's main adviser under new procurement guidance drawn up by the Treasury.

Draft guidances 4, 5 and 6 contain advice on teamwork and partnering, procurement strategies and financial aspects of projects as part of the government's drive to take on board the Latham and Egan reports and become a better client.

But consultants are worried that the guidance, which will make Joint Contracts Tribunal and Institution of Civil Engineers' contracts obsolete, will leave too much power in the hands of contractors.

Construction Industry Council chief executive Graham Watts said consultants' worst fear is that they will end up as subcontractors.

"I believe the contractor should be involved from early on but it should not be contractor-led," he said.

"I can't think of any examples where contractor-led design has led to an enhancement of the built environment." Watts claimed that most of the innovation and intellectual force in building came from consultants, and he predicted that the swing towards contractor-dominated construction would not last.

He said: "Public sector clients will soon get fed up with the sort of buildings they get." Watts believes that, although the guidance marks a move away from the traditional role of the consultant, it should be seen as an opportunity for consultants to work more closely with contractors.

He said: "Clients will get better buildings through a partnership arrangement where all parties are regarded equally rather than where a main contractor takes all the design responsibility." Treasury procurement head Mike Burt said the guidance had been drawn up to reflect the major change in the industry in recent times.

He said: "They are guidance notes only, but they are important reference points. They carry a lot of weight."