With the help of glass and large stainless steel panels, the entry pavilion of the recently opened National September 11 Memorial Museum is on par with the “Reflecting Absence” design of the memorial at the World Trade Center site.

The global architectural firm Snøhetta was commissioned in 2004 to design the pavilion, which stands on top of the underground museum and is the only building on the memorial plaza. According to Snøhetta project manager and project director Anne Lewison, glass makes up 22 percent of the outside of the pavilion.

“Our intention was that the pavilion should have as much glass as possible,” says Lewison, “but we needed to reduce the overall percentage of glass and keep it focused on the atrium at the west side of the building and closest to the center of the memorial to meet the security requirements.

The pavilion at the National September 11 Memorial, which stands on top of the underground museum, is the only building on the plaza. (photo credit: Joe Woolhead)

“In addition to meeting the sustainability criteria, the low-E coating allowed fine reflective surfaces on all sides of the building. “

W&W Glass held the primary contract for the pavilion project but hired out much of its work to several contractors. Bruce Hernsdorf, project manager at W&W, says the “full spectrum” of glass was used on the project, including tempered, laminated, insulating and coated.

According to Snøhetta, the pavilion is “on target to receive a LEED rating of Gold,” as it boasts “a number of sustainable features including optimized minimal energy performance, daylight and views, water efficiency, wastewater re-use,” while using “low-emitting and locally-[sourced] materials and fabricators wherever possible.”

Island International Exterior Fabricators handled the stainless steel mega panels, and Post Road Iron Works Inc. created the structural steel framing where the original World Trade Center “tridents” are housed, as well as steel supports, mechanical platforms and stair towers on the site. Erie Architectural Products did the aluminum curtainwall veneer and storefront, and Viracon provided the glass.

“It was extremely rewarding to work on a project with such national and historical significance,” says Hernsdorf. “It was not just another project. It was special.”

W&W began its on-site work in mid-2009 and was “full-bore” on the project until the 10-year anniversary, when funding dried up, according to Hernsdorf. The company still maintained a background presence in the project until it picked back up a year later.

Hernsdorf said he had as many as 50 workers on site at once during the busy portions of the project, with an average of about a dozen at a time on a daily basis from beginning to end. He credits “the use of sophisticated 3D modeling” in the speed of which it was completed, adding that “there were very, very few right angles.”

“It was all done in advance,” he says. “Nothing was field measured.”

Lewison elaborates on the design of the pavilion, which stands next to two reflecting pools formed in the footprints of the original Twin Towers, as well as a plaza of trees.

“The role of the museum pavilion in the center of the WTC memorial is to mediate between the trees and the waterfalls and the commercial towers around the site,” she says. “. . . The Plaza Level glass provides an opportunity for visitors to see the Memorial and the trees reflected back at them in a way that we have called ‘Reflecting Presence.’

“The pools reflect the past, the horror of the event and the absence of the towers and the victims. The Pavilion reflects the season and the weather, and families and friends moving around the memorial is a confirmation of the present and great hope for the future.”