The Ledge at Willis Tower Closed after Sacrificial Glass Layer Cracks
Willis Tower officials closed all four boxes of The Ledge, the 103rd floor tourist attraction atop the Chicago skyscraper, after cracks appeared in the sacrificial coating layer designed to prevent scratches on the glass, according to an NBC News report.
Alejandro Garibay, his brother, and two cousins were in the glass enclosure that juts out of the west side of the building shortly before 10 p.m., May 28, when Garibay said they heard cracking. The visitors stepped off the glass and immediately alerted a staff member.
Glass fabrication officials as well as Brian Rehme, spokesman for public relations firm FleishmanHillard, reported that the structural integrity of The Ledge boxes is sound and that the visitors were never in danger.
When the tourist experience opened in 2009, engineers said the boxes were composed of three layers of glass each about one half-inch thick. They were built to hold five tons, officials said.