One World Trade Center, whose steel core is two-thirds complete, is due for a makeover of part of its exterior.
Prismatic glass panels intended to beautify the first 20 floors of the 1,776-foot skyscraper have proven delicate enough to shatter, forcing the architects and glass manufacturers to conjure up a new design.
“As design moved to the testing phase, it became clear that the prismatic glass simply had too many technical problems to overcome and at a budget that was not cost effective,” said John Kelly, a spokesman for the Port Authority of New York and New Jersey, which is managing the construction of 1 W.T.C. and overseeing the redesign of the podium’s glass. “We have been finalizing a design that will be far more practical while being both distinctive and magnificent.”
The redesign, estimated to cost between $5.5 and $6 million, is currently under way and will not affect the completion of the tower scheduled for 2013, according to the Port Authority. The podium glass wouldn’t be installed until 2012, as originally scheduled, because the building’s lobby space is currently being used to feed construction supplies to its upper floors. There will ultimately be 82 floors plus a spire.
The prismatic glass design for the lower floors of the building has cost $10 million. It was manufactured in China by DCM Erectors and Solera Construction, which entered into a joint venture to bid on the project and were awarded the $82 million contract in August 2008.
DCM-Solera didn’t return calls for comment, and Skidmore Owings & Merrill, the lead architect of the building, declined to comment.
Bill Yanek, executive vice president of the Glass Association of North America, wouldn’t comment on his thoughts about the redesign, but said, “We’re not aware of another project that has used the prismatic glass on such a scale as the W.T.C. was contemplating and now has abandoned.” G.A.N.A. is a trade association comprised of more than 300 member commercial and architectural glazing companies, including Viracon, the largest glass fabricator in the country, which was hired to design the glass façade above the podium.
Viracon purposely steered clear of the prismatic glass when the firm first conceived the design for the upper floors of the tower. “We chose not to bid on that glass in the original design, because it was a technically challenged composition that hadn’t been proven for our company,” said Christine Shaffer, Viracon’s marketing manager.
— Aline Reynolds
