 At
a cost of $700 million to construct,
Seven's ex-terior walls will
conserve energy, and collected rainwater
will help with cooling and irrigation.
The building boasts a 2-foot-thick
solid concrete core, which will
provide much higher impact resistance
and will house the exit stairs,
utilities infrastructure, and elevators.
The stairwells will be 20 percent
wider than currently required, and
they will be pressurized, which
will prevent smoke from entering
and remaining in the stairwells—a
requirement by city codes all over
the world but not in New York. A
recent federal safety report found
the staircases—their number,
weak walls, and location—in
the Twin Towers to be critical factors
in the deaths of many killed on
Sept. 11. Looking up at the building's
ground-to-sky glass exterior, which
was just being finished as Prism
went to press, you get a sense of
just how magnificent engineering
can be. —Lynne Shallcross
|
Seven
WTC looms 750 feet in the air, offering
a dramatic contrast to the 16-acre
hole in the ground next door. The
bluish-tinted building, a 52-story,
1.7 million- square-foot office
tower, stands for more than just
the WTC rebuilding. It will also
serve as a role model for future
tall buildings in terms of innovative
engineering. Some are already billing
it America's safest and "greenest"
skyscraper. 
