ETFE’s Pyramid on the Rooftop of a Skyscraper to Adorn the Nightscape

Taiyo Kogyo’s U.S. subsidiary, Birdair Inc. (Birdair), has completed a pyramid-shaped structure on top of a high-rise building.
This extremely impressive structure installed atop a landmark building in the city overcame various difficulties, including difficult construction conditions and a shortened construction period, before its completion. The building, called Legacy Union, completed in Charlotte, North Carolina, USA, is approximately 200 meters tall, making it the fourth tallest building in Charlotte. Birdair was originally contracted to value engineer the ETFE film pyramid structure and was ultimately awarded the contract to design, fabricate, and install the ETFE film, clamping hardware, reinforcing cables, and steel frame. The steel frame fabrication and installation was performed in cooperation with Steelfab, a major steel frame contractor in Charlotte. The steel frame needed to be pre-assembled prior to lifting, but it was difficult to find a suitable location in the heart of the city. Careful preparation was also required to hoist the steel frame to the roof of the building. Finally, two tower cranes provided by Gilbane and Shelco, the general contractor for the structure, were used to hoist the steel frame. Birdair developed a three-tiered scaffolding system for the property in order to place the steel frame on the penthouse atop the building, and the pyramid was successfully erected.

As the project progressed, the overall process changed, and in response to the client’s request, Birdair was able to accelerate the process beyond the original schedule. As a result, the structure was completed an additional four weeks ahead of the shortened process and eight weeks ahead of the original schedule. In addition, the winter months meant that the ETFE film had to be handled with care, but fortunately, good weather conditions throughout the construction period allowed for a successful completion of the project. Thanks to the efforts of Birdair’s team and subcontractors, we were able to successfully deliver a new architectural addition to the Charlotte cityscape.