1 PENN PLAZA

1 Penn Plaza represents a major adaptive reuse and modernization project that transformed a 1960s office tower into a contemporary asset. The existing structure, originally built during Manhattan's postwar commercial boom, required substantial systems upgrades to compete in today's market. Vornado Realty Trust commissioned the renovation, partnering with MdeAS and A+I on the architectural and engineering strategy.

The project's energy performance improvements centered on a comprehensive window replacement program throughout the tower. Triple-glazed windows were installed across all occupied floors, a significant upgrade from the original single or double-glazed assemblies typical of 1960s construction. The triple-glazed system substantially reduced thermal transmittance and improved condensation resistance, directly addressing one of the primary energy liabilities of aging office stock. This window replacement required careful coordination with existing floor slabs, spandrel conditions, and structural frame tolerances—a common challenge in retrofit work where new components must interface with aging infrastructure that may have settled or shifted over decades.

The ground floor received particularly dramatic intervention. The entire ground level was demolished and rebuilt with a new limestone-clad curtain wall system, creating a contemporary street presence that contrasts sharply with the tower's mid-century aesthetic above. This strategy allowed Vornado to anchor ground-floor retail and lobby experiences with modern materials and environmental performance while preserving the existing structural frame above. The limestone ground floor also serves a practical function: it visually and materially separates the renovated commercial tower from the pedestrian realm, establishing clear sightlines to retail signage and creating a more inviting street-level experience than the original 1960s facade would have provided after decades of weathering and obsolescence.