The Hubert
H. Humphrey Metrodome, known as The
Dome, is the crappy stadium that, sadly, the Minnesota Vikings call
home.
The roof of the Metrodome is
air-supported. It requires 20, 90-horsepower industrial fans to pump it full of 250,000 feet of
air a minute to keep the roof inflated. The roof is made up of two layers. The outer layer is very thin and is made of Teflon-coated fiberglass. The inner layer is made of fabric. There is lots of dead space between the two layers. This space contains the fans, that blast the space full of hot
air to insulate the roof.
In the winter, the temperature of the roof-supporting
air is turned up. This helps melt the heaps of
snow that fall in Minnesota and builds up on the the roof… and as it turns out, it doesn't do that good of a job.
During the 2010 Minnesota Blizzard, well over 17 inches of
snow fell in the Minneapolis-St. Paul area. The record snowfall caused the roof of the Metrodome to collapse.