The new, $500-million retractable roof at BC Place stadium won't be able to close when it's raining or there are high winds.

Officials say the retractable roof, which seemed an ideal fit for the West Coast's rainy and quick-changing weather, shouldn't be closed while it's raining because of possible issues with water pooling.

As the roof closes, the fabric creates folds that will become gathered in the centre of the stadium. Officials say the weight the water would create in the folds could potentially create a tear in the roof.

"You can't have those folds collect water, especially with the size of the roof," BC Place Stadium General Manager Howard Crosley told reporters at a press conference Monday.

Crosley said the problem won't affect fans, whose seats will be permanently protected by the outside portion of the stadium at all times.

"The only thing that will be affected is the players on the field. And they're used to playing in open air stadiums, so that shouldn't be a big problem," he said.

Crosley said BC Place doesn't anticipate having to cancel any sporting games because of weather. He added that the decision whether the roof will be open or closed during games will be made far in advance.

The roof, which will be the world's largest cable-supported roof in the world, takes about 20 minutes to fully open or close.

Stadium officials say they chose to install a retractable roof because of the original design of the building, saying its design would not support a metal retractable roof like the one at Toronto's Rogers Centre.

"All of the structure that exists wasn't set up to handle the very significant weight of a metal retractable roof. This technology was sourced through engineers that have worked with our building before," Crosley said.

Crosley admitted a fixed roof would have cost less money, but says the new retractable roof will enhance the ability to market the venue for special events.

Since 1983, BC Place has averaged more than 200 event-days a year, generating $58 million annually. The government says the new retractable roof will add an additional 41 event days per year.

It is scheduled for completion by summer 2011, in time for the Grey Cup and for the Vancouver Whitecaps' first season as a Major League Soccer franchise.

BC Place is run by the BC Pavilion Corporation, which is owned by the provincial government.