Tishman Contributions

John Tishman, then the president of Tishman Realty and Construction, Inc., was the general contractor for the World Trade Center. In these audio excerpts from a 2002 lecture for The Skyscraper Museum, presented with Leslie E. Robertson, the chief structural engineer of the towers, and in a solo oral history recorded in August 2006, John Tishman describes four key features of the buildings’ design that were changed in response to his suggestions to facilitate construction and stay on budget:

Moving the mechanical systems to the lower levels of the building, rather than following the conventional practice of placing them on the roof.

Chamfering the corners of the buildings to create a 2-story opening to allow for hoisting materials into the interior.

Dividing the steel contracts for bidding by specialized suppliers to keep down costs.

Substituting high-polished aluminum cladding for the tower columns rather than stainless steel.