The Vikings are looking to make the southern half of their stadium out of a membrane that is opaque. The membrane is often referred to as ethylene tetrafluoroethylene (ETFE) supported by steel. The dome will get a new natural light that will most likely cut down on it’s expenditures.

We previously saw an example of ETFE in 2008 during the Summer Olympics.

There will be five 95-foot-high retractable doors on the west side that will pivot to open, connecting the building to a public plaza and highlighting views of the downtown Minneapolis skyline.

Source: http://www.twincities.com/politics/ci_23235098/vikings-verge-unveiling-final-stadium-design