Just over a year ago, we got an exclusive sneak peak at Renzo Piano‘s much-celebrated new Modern Wing at the Art Institute of Chicago (here’s parts two and three of our early look). At the time it opened, it was the talk of the town, helping to solidify the city’s architectural legacy. Oh but how quickly the honeymoon has come to an end. The building has now found itself at the center of a lawsuit between the museum itself and the British engineering firm that helped build it, Ove Arup & Partners. The museum alleges that the firm performed shoddy work in a number of areas, resulting in millions of dollars spent on repairs. Ove Arup has said it’s shocked by the suit, saying that it had been trying to work out any problems with the museum since apparently early 2009, before the building had even opened. According to Engineering News Record, the museum says that “the talks went nowhere” and so they had little choice but to file suit earlier this week in an effort to recoup the money spent fixing the problems. Here’s a list the issues that make up the lawsuit:

The dispute centers around alleged errors and omissions in heating and cooling systems, concrete floors, the building envelope, a portion of the roof referred to as the “flying carpet,” a pedestrian bridge, as well as “incorrect structural engineering.” It also alleges Arup provided an insufficient number of experienced engineers to handle construction administration, which contributed to “costly delays and required revisions to work already completed.” The claim says AIC spent or will have to spend some $10 million as a result of Arup’s poor performance on the project.

If there’s one person resting easy while this courtroom battle kicks off, it’s Renzo Piano, whose design for the building isn’t being held at fault by the Art Institute.