Minnesota Blizzard Collapses Metrodome Roof [PHOTOS]

A blizzard for the ages collapsed one of the most iconic landmarks of metro Minneapolis on Sunday morning: the Metrodome. The home of the Minnesota Vikings and former home of the Minnesota Twins could not stand the weight of the 17.1″ of snow that had piled on the Teflon roof over the preceding 36 hours.

For the short term, the Vikings-Giants game that had been rescheduled for Monday night at the Dome will be played in Detroit instead. The NFL has promised free tickets to anyone who wishes to attend the game, as well as preferred seating at the 50-yard line for anyone who has tickets for the Metrodome game and wishes to make the frigid trek to Detroit.
For the longer term, the Metropolitan Sports Commission–the organization that manages the Metrodome, is considering all of their options to repair the roof.

The massive taurpaulin roof — nearly 10 acres in area — collapsed under the cumulative weight of over 17 inches of freshly-fallen snow.

Aerial photos show the roof tore in two places in the center and one near the edge of the roof.

The Metrodome’s roof is made of two layers of Teflon coated fiberglass fabric, and is an air-supported structure supported by positive air pressure. To maintain the differential air pressure, spectators usually enter and leave the seating and concourse areas through revolving doors, since the use of regular doors without an airlock would cause significant loss of air pressure. The double-walled construction allows warmed air to circulate beneath the top of the dome, melting accumulated snow.

A sophisticated environmental control center in the lower part of the stadium is manned to monitor weather and make adjustments in air distribution to maintain the roof. However, such technological efforts aren’t always sufficient to maintain the integrity of the roof.

The roof has deflated five times in the stadium’s history. On November 19, 1981, a rapid accumulation of over a foot of snow caused the roof to collapse, requiring it to be re-inflated. It deflated the following winter on December 30, 1982, again because of a tear caused by heavy snow. In the spring following that same winter, on April 14, 1983, the Metrodome roof deflated because of a tear caused by a late-season heavy snow, and the scheduled Twins’ game with the California Angels was postponed. On April 26, 1986, the Metrodome roof suffered a slight tear because of high winds, causing a nine-minute delay in the bottom of the seventh inning vs the Angels.

Officials haven’t fully assessed the damage from the recent deflation, though they are optimistic the roof can be repaired before the next home Vikings game against the Chicago Bears on December 20th.