For SOM, WSPCS, the local mechanical-electrical-plumbing engineer Baros Baum & Bolles and Tishman, construction of the replacement for 7 WTC, which collapsed on 9/11, was a rehearsal for 1 WTC. The 52-story 7 WTC, open since 2006, was also a steel-first building (ENR 9/12/05 p. 37). For it, Tishman worked out both technical and labor issues.

The steel-first sequence begins with three floors of steel trailed by two of deck. Three floors of deck concrete follow. Two floors of shear walls come next, trailed by four floors of core slab and stairs. For six floors below that, workers fireproof steel. The curtain wall brings up the rear.

To date, the only big snafu concerns a redesign of podium cladding, prompted by the glass maker's inability to meet the specification. SOM says a redesign will be ready this fall. Solera/DCM holds the cladding contract.

The individuals building 1 WTC report that the job has changed them and their firms—and not only due to emotions associated with building a tower rising from Ground Zero. Estevez sums it up, saying, “This is not a cookie-cutter building.”