Speaking at the launch of Egan's Accelerating Change report, Alan Ritchie, UCATT's regional secretary, said he was disappointed with its content.
He said that the role of trade unions in the industry had been buried and that employers needed to support unions further.
Ritchie added that the industry needed to address the issue of bogus self-employment and tax evasion before it could even begin to solve other far-reaching difficulties, such as training, the skills shortages and the recruitment shortfall.
Ritchie said: "The biggest problem is that you cannot train and develop people unless workers are properly employed in the first place." He added that UCATT wanted changes made in the industry to meet the unions' agenda.
John Gains, the president of the Construction Confederation, who headed the strategic forum's "people issues" working group said he shared the unions' fears.
He said: "We are very concerned about bogus self-employment and we need to find a working agenda.
You cannot train people unless they’re properly employed
Alan Ritchie, UCATT
I understand the problem."
He added that the image of the industry lay at the heart of the industry's ability to attract, develop and retain the best human resources.
Construction minister Brian Wilson said there needed to be a partnering approach to employer–union relations, as that would "ensure that common ground can be found to help solve problems".
Sir John Egan formally handed over the chairmanship of the strategic forum to Peter Rogers, a director of developer Stanhope, at the launch of Accelerating Change.
Rogers said that there were still groups within the construction industry that had either not heard of or not acted upon the Rethinking Construction message.
He said: "We need to make sure that the forum is as inclusive as possible, and its strategy as clear and as simple as possible."