DENVER (CBS4) – An inspection of the celebrated tented roof over Denver International Airport in late 2021 revealed “critical” issues in some of the cables supporting the roof. Inspectors say some steel cables were “overloaded” and others were at risk of failure.
“There is concern of failure in the 20 more severe cases,” wrote the inspectors. “Though we cannot say how soon a failure may happen, we do not recommend on waiting on replacement of these cables.”
The report was delivered to airport managers Jan. 7, according to a CBS4 Investigation. Nearly five months later, DIA officials acknowledged “critical” repairs urged by inspectors have not been done, but are still being evaluated.
“That team is currently working through their investigation, meeting weekly to discuss progress,” said the airport’s Senior Vice President of Communications, Stacey Stegman. “The report from the structural engineer should be expected in June or July when we will define the project to make the repairs.”
The roof is inspected annually by Birdair, a New York-based contractor which was involved in the initial creation and installation of the DIA fabric roof. The airport opened in 1995.
Inspection reports of the roof over the Jeppesen Terminal, also known as the Great Hall, for 2019 and 2020 were routine and contained few critical or noteworthy issues.
However the 2021 inspection, which was conducted over the course of two weeks in November and December of last year, was a different story.
The Birdair inspectors noted 40 cables in the upper reaches of the terminal appeared to be “crushed at the strut tips. There is concern of failure in the 20 more severe cases… Though we cannot say how soon a failure may happen, we do not recommend waiting on replacement of these cables. This item sure to be prioritized as ‘critical,'” wrote the technicians.
They went on to write the “East and West glass curtain wall cables on exterior are in poor condition, cables exhibiting a ‘crushing’ effect which indicates cables are likely overloaded… crushing effect in cables not previously observed in previous inspections and is believed to be a recent development. Cable failure is of concern, this was immediately brought to DEN’s attention.”
Jim Starling, DIA’s Executive Vice President and Chief Construction and Infrastructure Officer, told CBS4 even if some cables failed, it would not be a catastrophic event.
“The structure is engineered for redundancy,” said Starling. “It takes into account issues like that coming up. If an individual element failed, there is still redundancy within the structure.”
The inspectors also noted drain pans suspended from the West Curbside Canopy had come loose and were “a falling hazard” and were a “critical” item.
“The issues they identified,” said Starling. “We take care of them.”
The inspection also revealed some large tears in the tented roof, ranging in size from 3 feet to 6 feet in length. The technicians said they repaired four large tears during their inspection and said some of the tears and damage occurred during the Great Hall renovation project.
They said in a high wind event, the tears could have become much worse and caused widespread “panel failure” if they had not been found and repaired.
The fabric roof that spans the main terminal is the length of three football fields and totals about 375,000 square feet. The roof is showing its age, and it has been recommended the 400 ton covering should be replaced in the next five to eight years.
Starling said the airport is “programming right now to replace the roof in our next capital improvement program.”
He said it is too early for a cost estimate, but he said the replacement project will begin with design work.
“We got the iconic roof,” said Starling. “And we need to make sure it stays in great shape.”