This project involved a unique combination of construction and logistics for the redevelopment and renovation of an existing 267,000-GSF, 18-story limestone-clad office building, along with the challenge of constructing a 3-story addition at the top, while remaining occupied and functioning during the construction process. The existing building - built in 1949 - was occupied on the first eight floors and stayed occupied and operational during the construction phase. The existing "wedding cake" building was built out, standardizing the floor plate and creating common leasable floors. Upon completion, the glass curtainwall and steel structure totaled 302,000-SF of gross office space in 21-stories.

The exterior limestone façade was stripped from the 18th floor down to the 10th floor, where a temporary protective roof was built and maintained through a full season. Construction consisted of selective terrace and structural demolition along with new structural steel and reinforcement of existing support members from the 9th floor up. The mechanical and electrical equipment were replaced and relocated in their entirety in a phased sequence, while keeping all existing systems operating for the occupied, lower eight floors.

The greatest challenge at 640 Fifth Avenue that our team encountered began in the preconstruction phase, which involved blending the best logistical and construction approach to perform the renovation and new construction work in a occupied and operational facility without disrupting the various tenants and retailers in the building, as well as pedestrians on the adjoining sidewalks, frequenting Rockefeller Center.

The potential for disruption included the various phases of construction, such as the erection of the new steel structure, installing the glass curtain wall, construction of a temporary roof at the 10th floor, reinforcing the steel columns and window replacements on multiple floors. One solution was to eliminate the use of a hoist to load materials to the upper floors of the building during the construction phase. Instead, the team used a tower crane that also served to erect the structural steel, while maintaining zero disruptions to the building's systems, while installing the new MEP systems.

This project was the recipient of New York Construction’s 2004 Renovation Award of Merit.