For this year’s U.S. Open, the world’s largest tennis-specific stadium, Arthur Ashe Stadium, got a makeover. In response to the need to avoid rain delays, the United States Tennis Association (USTA) approached Detroit’s Rossetti Inc., which originally designed the stadium in 1997, to see if the company could design a retractable roof for the stadium.

The original stadium was comprised of a concrete-topped steel structure combined with precast hollow core slabs at the superstructure level, a cast-in-place slab at court level and steel frames spaced radially around the stadium. So Rossetti Inc. collaborated with WSP (the architecture firm behind the One World Trade Center) and decided to replace it with a lightweight composite retractable roof.

The roof has 191,400 square feet of fiberglass panels, each coated in 0.03 inches of polytetrafluoroethylene (PTFE), a Teflon-coated membrane installed by Birdair that is lightweight yet incredibly durable in keeping out the elements, especially the sun. While it allows outdoor quality of daylight transmission, it blocks 90 percent of the solar radiation.

“We had a bold vision for transforming this entire facility, and the roof was a huge part of that,” USTA executive director Gordon Smith told USA Today. “It worked flawlessly.”

According to The Detroit News, the roof takes about six minutes to open or close, and meets New York’s code for hurricane-force winds. Birdair adds that the new roof, which is expected to be used only for rain, opens at a top speed of 25 feet per minute, despite being the size of 17 Olympic swimming pools.

To see a close-up opening of the roof, check out this video below: