Construction continues on Louis Armstrong Stadium at the Billie Jean King National Tennis Center in Queens, N.Y. (U.S. Tennis Association)

The new Louis Armstrong Stadium converts the site of the old facility into one of the Grand Slam tournaments' most intimate large tennis venues, topped by a retractable roof to keep spectators dry, says Jon Disbrow, Rossetti's lead architect for the project.

Last week, project officials marked the topping out ceremony, tied to the final piece of steel installed for stadium construction. The $180 million job is a complete rebuild of a facility originally constructed for the 1964 World's Fair in New York. It served as the primary court at the U.S. Tennis Association's Billie Jean King National Tennis Center before 23,000-seat Arthur Ashe Stadium opened in 1997. The new Louis Armstrong Stadium, situated next to Ashe, will seat 14,000, starting with this year's U.S. Open.

Rossetti, in tandem with general contractor AECOM Hunt and roof designer Morgan Kinetic Structures, kept the cost for building a midsize venue with a movable roof under $200 million by developing a theme of efficiency. A big savings was achieved by not having to design as many HVAC systems for the naturally ventilated building, Disbrow said.

“We didn't have that major expense,” he said. “It's effectively an outdoor stadium.”

The rectangular building expands seating for the USTA's second-biggest facility by 4,000 and the total footprint adds more than 50,000 square feet over the old setup. Despite the bigger layout, the seating bowl is tighter, with an equal distribution of 7,000 chairback seats between the lower and upper bowls.

As part of developing a tighter bowl, Rossetti eliminated a walkway that cuts through the lower deck, a change that pushes seats that were once behind the cross-aisle closer to the court. The architect designed the upper deck to cantilever over the lower bowl, moving the highest seats closer to the action as well. Overall, the bowl's steeper rake improves sightlines for all fans.

“The seats are right on top of the court,” said Danny Zausner, the USTA National Tennis Center's chief operating officer.

The biggest upgrade is the retractable roof, which falls in line with other Grand Slam facilities switching to roof cover to minimize disruptions in play during rainy weather. At the U.S. Open, 25 percent of the crowd typically comes from outside the U.S. Starting this year, they don't have to worry about bad weather affecting matches at the National Tennis Center's top two venues, Zausner said.

In its functionality, Armstrong's roof is similar to Arthur Ashe Stadium's retractable roof, a $500 million retrofit completed in 2016. At Louis Armstrong Stadium, the flat roof powers a smaller load.

Armstrong's roof is expected to open and close in five to seven minutes, the same as Ashe's dome-shaped roof, he said. At both facilities, the roofs are designed to deflect rainfall overhead with the sides open to the elements. (Both roofs are made of PTFE, a lightweight plastic material similar to ETFE, used at new NFL stadiums).

“We designed [Armstrong] to operate like standing under an umbrella,” Disbrow said. “The [sides] are still open with air flow during the rain. It's not like sitting inside an air-conditioned stadium.”

Armstrong's exterior features Oko Skin, a fiberglass concrete product made by Austrian firm Rieder Gruppe that comes out of the box in three textures, Disbrow said. Rossetti used the same material for designing Ariens Hill, the new sledding facility at Titletown, the Green Bay Packers' mixed-use district next to Lambeau Field.

New and bigger video boards at both ends of Louis Armstrong Stadium and food upgrades tied to 95 points of sale, about six times the original number, are other improvements. Levy runs the concessions and will have a 5,000-square-foot commissary to prepare food. There was no cooking infrastructure at the old Armstrong, Zausner said.

Aramark, entering its second year of operating U.S. Open retail, will work out of new stands featuring Wilson and Polo merchandise underneath the lower bowl.

This year's U.S. Open marks the event's 50th anniversary. The opening of new Louis Armstrong Stadium will complete a five-year transformation of the National Tennis Center with more than $600 million in improvements.