Exactly with the Metrodome,BC Place Stadium in Vancouver had the same kind of roof as the Metrodome. They refurbished BC Place & replaced its roof with a retractable roof that has cables attached to the roof enclosure like spokes on a wheel. The cables pull the retractable roof out like putting up a sail on a sail boat.just in 360 degree directions. The Vikings can play in TCF Bank Stadium,which by the way can expand their seating from 50,000 seats to 80,000 seats,& I'm very sure can have heating installed in the causeways for wintertime play. The Vikings' ownership is just so myopic about getting a brand new palace,they don't want to see or consider those options that I've given.
There are a lot of reasons why they may not want to go with existing venues, probably mostly has to do with who owns them and the politics and costs involved in using those properties. For example, it cost them almost $1.8m to play their disrupted home game on TCF Bank Stadium after the roof caved in in the Metrodome. They've nearly paid that debt off - Vikings have nearly paid off university for using stadium - NFL - Yahoo! Sports