Restrictive CFMEU conditions on Queensland sites risk dragging out work and making apartment buildings up to a third more expensive to build, a new analysis suggests.

Queensland Economic Advocacy Solutions found the construction union’s latest agreement conditions, such as union veto on concrete pours and stoppages to attend union rallies, risked adding 18 to 33 per cent extra to the cost of an apartment build in the state, depending on how often the conditions were applied.