New York skyscraper uses Ancient Roman flooring technique

A recently converted skyscraper in New York has utilised technology similar to that used in the construction of the Pantheon, which dates back to 126 AD.

The concrete floors in tower blocks use steel beam grids for support and are considerably heavy. Incorporating air voids within these flooring structures reduces their weight. The architects behind the Pantheon utilized empty terracotta blocks to create air-filled cavities that decreased the floor weight.

During the conversion project at 1 Wall Street, a comparable technique was used when adding extra floors to the building. Instead of using terracotta blocks as seen with the Pantheon builders, plastic spheres were utilized to produce air voids. Mark Plechaty, a consultant engineer on this project revealed that concrete void floors have been used by New York City buildings since as early as the 1920s. However, modern use of this technique only began in earnest during the 1990s.

It is estimated that every pound of plastic deployed towards creating concrete voids removes the need for approximately one hundred pounds of concrete, while also reducing costs, making it an ideal solution for integrating additional concrete flooring into any building structure.

Concrete void flooring is increasingly popular around the world, with several variations of the technology competing for market share. As well as floors that use plastic spheres to create voids, polystyrene has been used. The flooring can be constructed on-site, or pre-made concrete slabs are available. It is predicted that the use of concrete void flooring will become even more popular in the coming years.