Architects continue to push the envelope of retractable roof design. Consider the concepts emerging from 360 Architecture for the Atlanta Falcons new stadium, which is being billed as an open stadium that closes, as opposed to a closed stadium that opens.

The 11-sided geometric building would feature an eight-sectioned roof that would twist open like the aperture of a camera. "The interesting thing is even though we have eight parts, they're much smaller than other roofs out there and they have to go a shorter distance," 360 Architecture's Bill Johnson told WXIA-TV, Atlanta's NBC affiliate.

In addition, transparent polymers serving as stadium walls would allow views of the Atlanta skyline. "A lot of retractable roof stadiums just haven't been open very often," Falcons president Rich McKay said. "As good as our weather is, and as good as our environment is, and the fact that we have downtown adjacent to us, we've always wanted that connectivity."

While McKay lauded the design team for its "creativity," the concepts face a vote of the Georgia World Congress Center today and are subject to change.

Paul Steinbach is Senior Editor of Athletic Business.