Officials at Vancouver's B.C. Place are searching for answers after the stadium's inflated dome roof — destined for the spotlight in the 2010 Winter Olympics — collapsed on Friday. 

With a sound "just like thunder," the Teflon-coated roof fell, leaving the torn fabric hanging over the Vancouver landmark and a giant hole in the city's skyline.

The roof of B.C. Place Stadium collapsed with a loud bang in Vancouver on Friday.
(Kevin Kimmet/CBC)

B.C. Place officials said the collapse was an intentional controlled deflation after one panel of the roof was torn off.

However, general manager Howard Crosley told a news conference Friday afternoon that it was still not known what caused the initial problem.
 
"At this particular point in time, we're still assessing what that was. We also conducted a standard evacuation of the facility in the interest of public safety."

'Like elephants running through your living room'

Two City of Vancouver workers told CBC News they heard the fabric flapping, followed by what sounded like an explosion, ripping a hole in the inflated roof of the building that is to host the opening and closing ceremonies for the 2010 Winter Olympics.

Part-time stadium worker Trevor Holness was inside the facility during the noon hour when he noticed that the roof was sagging.

This is a view of B.C. Place Stadium from the Library Square Tower.
(Kevin Kimmet/CBC)

He said he was warning other workers about the possible danger when "huge gusts of wind caught the slack in the roof, and it was an intense sound."

He described it as the sound of "elephants running through your living room. It was thunderous."

Holness said there was a seven-metre tear in the roof that "grew across the bottom and travelled up one side, and there was like the whole corner flapping, the sound was insane."

Paul Walker, who was also working inside the stadium, told CBC Radio the tear sounded "just like thunder." He said that the air in the dome then started "being sucked out really fast."

He said water started pouring down from the hole in the roof. It had been a snowy, rainy day in B.C., but there's no word on whether that was a factor.

There were no reports of any injuries.

Crosley said a new panel to repair the roof has been ordered. But he could not say when the roof will be repaired and the dome re-inflated.

Poor maintenance cited by NDP

The New Democrat MLA for Delta North says a lack of proper maintenance may be to blame for the roof collapse.

Guy Gentner first raised the issue in the legislature last May, warning the roof was in bad shape.

"B.C. Place Stadium is close to its end. The roof is ready to fall down, according to the service plan. Its anticipated lifespan is coming to an end. Could the minister tell us when the life-cycle replacement is due on the roof at B.C. Place Stadium?"

Olga Ilich, who was then the tourism minister, offered this reassurance.

"Apparently the roof is expected to last another 15 to 20 years if it's maintained properly in its current state," she told the house.

She also confirmed that it costs more than $300,000 a year to maintain the roof.

The stadium, which is home to the B.C. Lions football team, seats 60,000 and was completed in 1983, three years ahead of Expo 86. It has been the largest air-supported stadium in the world.