The Spiral – 66 Hudson Boulevard, a 67-story office building, was built in the Hudson Yards neighborhood of Manhattan. Standing at 1,031 ft tall and featuring 2.85 million sq ft of office space, the building’s design includes terrace gardens along the exterior in the shape of a spiral, leading to the name of the structure. Roughly 30,000 tons of structural steel were fabricated for the project, and ironworkers and operating engineers completed more than 500,000 hours of steel erection.

“When embarking on the Spiral, we set out to create the ultimate modern, collaborative and sustainable workplace,” says Chris McCartin, senior managing director of design and construction at Tishman Speyer. “The tower’s defining feature, a cascading series of terraces that ascend in a spiraling motion to form a continuous green pathway that wraps around the facade, gives occupants readily accessible outdoor space on each tower floor.”

The building’s namesake spiral design was created using a multistory sloping column system.
Image courtesy WSP USA

Creating the spiral posed unique challenges to the construction team. A multistory system of sloping columns was used for the design but caused a substantial imbalance. The resolution was found in a system of horizontal floor steel trusses on each level of the building, transferring the loads to the core and stabilizing the structure.

Safety was of utmost importance to the project team. Construction manager Turner Construction instituted several stringent practices to ensure workers’ safety.

Steel mesh walkways were constructed, giving workers a balanced surface for moving throughout the job site, In addition, a metal screen cocoon system was attached to the building columns, stopping anything from falling during construction.

Adhering to a strict schedule, the project was completed on time and on budget.