Why London's Olympic Stadium has a roof

Olympic Stadium (Streeter Lecka/Getty Images)
Olympic Stadium (Streeter Lecka/Getty Images)

LONDON – Despite the sun beaming down on London this week, weather reports claim the United Kingdom is headed for its wettest summer since records began in the 18th century. Olympic track fans – and the athletes themselves – can therefore be grateful for the multi-million dollar roof erected over much of the Games’ showpiece stadium.

While the roof is positioned to ensure that the track and all of the 80,000 seats are protected from the elements, Yahoo! Sports reveals that the decision to add a covering to the stadium had nothing to do with comfort.

"A lot of people think the roof is there for the spectators," principal architect Rod Sheard said. "But it's not really."

The real reason behind the 112 specially manufactured PVC sheets stretched across the arena is to avoid an embarrassing scenario where potential world record times could be discounted due to strong winds.

[ Photos: London's Olympic venues ]

If a track race is completed with a following wind that reaches two meters per second, the time is considered to be "wind assisted" or "wind aided" and is therefore invalid for purposes of official records.

"If wind speeds are too high and the races are run tremendously fast, the world record would be disqualified," explained Paul Westberry, the principal engineer of the Olympic Stadium. "That would be terrible. Imagine Usain Bolt's world record being disqualified because the wind speed was too high.

"We had to design a building to protect the environment for the athlete to perform to [his or her] best."

Even though the entire field is not covered, the roof acts as a giant shield that diverts crosswinds over and above the stadium and prevents them from impinging upon the action on the track.

Previous Olympics have had wind-related issues, especially the Rome Games of 1960 when American Wilma Rudolph's Olympic record in the 100 meters did not enter the history books.

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"We need to shield the field of play and that is what the roof does," engineer Glyn Trippick said. "Without a roof, wind comes over the stadium and circulates and creates swirling conditions."

The Olympic site is susceptible to strong winds blowing from the southwest, although local meteorologists admit they have been baffled by the highly unpredictable weather patterns that have raged this summer.

Extensive rain in June and early July disrupted the Wimbledon tennis tournament and led to fears that the London Olympics would be severely affected. Games organizers have been delighted at the bright sunshine bathing the city in the early part of this week and have their fingers crossed for clear skies at Friday’s Opening Ceremony.

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