Part of a sweeping $100 million complete overhaul of the 42-story, 742,000 SF 330 Madison Avenue, MdeAS designed a custom curtainwall system to be installed over the existing exterior wall. The new curtainwall is comprised of high performance insulated glass units, greatly enhancing the energy performance of the building envelope. To attach the curtainwall to the existing tower, MdeAS developed a custom clipping system to anchor the panels directly to the existing mullions. Extensive testing was performed to ensure the existing system could support the additional load. Completing the transformation, MdeAS also expanded and renovated the lobby, introducing a palette of dark granite floors, beige stone walls and a custom designed ceiling and lighting system punctuated by a richly-veined marble feature wall.