There are fears for the fate of the Allianz Stadium rebuild as Multiplex, one of two builders competing for the contract, is suing Cox Architecture over their work together on another stadium project.

The Allianz Stadium rebuild has been fraught from the beginning, with many architects and civilians alike outraged at the decision to demolish and rebuild the stadium rather than completing a renovation to bring it up to current building standards.

Recently, the Berejiklian government has been forced to search for another builder for the project after Lendlease pulled out. Despite this, sports minister John Sidoti continues to assert that the project will be delivered on time and on budget. 

Multiplex was thought to be the favourite, considering it was shortlisted for the original contract, however the company is now suing Allianz Stadium architect Cox Architecture for the quality of its architectural services on Optus Stadium in Perth.

In the lawsuit lodged by Multiplex, the company claims that Cox’s services were “inadequate, erroneous, inconsistent with accepted practice at the time”. Multiplex also claims it was misled as to the quality of Cox’s services. "Those representations were false and ... amounted to conduct in course of trade ... that was misleading, deceptive or likely to mislead or deceive, which caused loss to the plaintiff in contravention of Australian consumer law," reads the lawsuit. 

The company is also suing engineer Arup over what it claims was poor geotechnical work and pedestrian movement modelling.

“We are in communication with both Cox and Arup who understand the status of the writs which have been lodged but not served,” a spokeswoman for Multiplex has told The Australian.

“It will have no impact on the potential delivery of the Sydney Football Stadium and we would welcome the opportunity to deliver another world-class stadium together. Multiplex has worked with Cox and Arup on a number of projects and we expect to continue our positive working relationship with both parties on future projects.”