The cracking was on the protective coating covering all of the Ledge’s glass surfaces, rather than the glass itself, a spokesman for Willis Tower told The Post.
“This coating does not affect the structural integrity of The Ledge in any way,” Brian Rehme said in an email. “Occasionally, the coating will crack, as it is designed to in order to protect the surface of the glass.”
The ledges, which opened in 2009, are made up of three sheets of glass and an invisible layer of resin all bolted to a steel frame at the top of the box. When the ledges opened, the construction chief described how even if all three layers were shattered, the floor would hold. “There’s no problem with putting 5,000 or 10,000 pounds without anything happening,” he told The Post. “It’s been tested.”