Constructed in 1957, the 39-story office building, encompassing 1.25 million square feet of commercial space, underwent a transformation where its original aluminum exterior was replaced with a contemporary glass, aluminum and steel curtain wall. This updated facade comprises 300,000 square feet of custom large-format curtain wall panels, creating seamless, mullion-free floor-to-ceiling windows extending from column to column, with each panel measuring 11′ x 20′. These expansive units significantly increase the window area in the office space, overcoming the challenge of the existing structure’s low ceiling height while enhancing natural light and panoramic views.

The redesign not only tripled the window area but also adhered to ambitious sustainable design standards, optimizing the efficiency of the building’s heating and air systems. Beyond the facade, the design team capitalized on the existing massing of 660 Fifth Avenue – featuring a podium and tower with various setbacks – to incorporate exterior terraces on three sides, including a notable east-facing terrace along Fifth Avenue.

Front actively collaborated on the project, contributing to the entire process from Concept Design through construction. The team meticulously developed, analyzed, and detailed the entire new envelope of the building. The resultant primary facade system is an unprecedented unitized curtain wall, showcasing the largest horizontal panels ever utilized in a redevelopment within New York City.