THE CANADIAN PRESS
VANCOUVER — The roof atop Vancouver’s B.C. Place stadium — the soft, marshmallowy centre of a downtown skyline otherwise crowded with concrete and glass — was deflated Tuesday to make way for a half-billion-dollar retractable replacement.
The dome roof came down after the power was pulled on 16 giant fans needed to keep it up, and crews were expected to immediately start dismantling the mix of fabric and steel cables that have covered the stadium for 27 years.
B.C. Place was one of the few remaining inflatable dome stadiums in North America.
Others include the Silverdome in Pontiac, Mich., the Carrier Dome in Syracuse, N.Y., and the Metrodome in Minneapolis, Minn.
David Bowick, who teaches architecture at the University of Toronto and whose engineering firm has a small role in the new B.C. Place roof, says inflatable domes have fallen out of favour for sports stadiums.
"They’re extremely pervasive for seasonal, smaller sports facilities — soccer domes, tennis domes — but for a stadium, they’re unusual now," said Bowick.
There’s a number of reasons.
While inflatable roofs are cheaper to construct than their rigid counterparts, those savings are eroded over time because of the cost of operating them, Bowick said.
Giant fans must be kept running to maintain the air pressure inside the dome, running up the stadium’s power bills.
Another problem is the air pressure can’t support heavy snow, which instead has to be melted — at a cost. That makes inflatable roofs less attractive for a northern country such as Canada.
And when they deflate, they are expensive to re-inflate and can also cost the operators for any events that must be cancelled.
All of those issues add up, said Bowick.
"Because your structural fail-safe depends on a mechanical system, you wind up with layers of redundancy and very important monitoring you have to do," said Bowick.
By next year, B.C. Place will be covered by a new retractable fabric roof supported by a series of cables and masts. The roof replacement will cost $458 million, and the province says it will extend the life of the stadium by 40 years.
The 60,000-seat B.C. Place was completed in 1983 in advance of the World Expo three years later, and has since been home to the B.C. Lions CFL football team. The Vancouver Whitecaps soccer team will play in the stadium beginning next year.
Earlier this year, the stadium hosted the opening and closing ceremonies for the Vancouver Winter Olympics, as well as nightly medal ceremonies during the Games and the opening ceremonies for the Paralympics.
B.C. Pavilion Corporation, the Crown corporation that owns and operates the stadium, has said most of the roof fabric will be removed and recycled over the next two months, while the spars supporting the new retractable roof should start appearing by July.
One of the first events to be held under the new roof will be the 2011 Grey Cup. In the meantime, the B.C. Lions will play in a temporary stadium located elsewhere.
The aging roof has had problems in recent years. In 2007, heavy snow caused a seven-metre tear in the roof, collapsing it. A month before the Olympics, water poured through the roof and caused a small flood inside.