Nick Wood/Alamy
CASE STUDY
Green Architecture
A recent addition to the Midtown Manhattan
skyline represents a new standard in
green architecture in New York City (see
photograph). Completed in 2006, the
Hearst Tower, home of Hearst Publishing,
was designed to achieve a degree of
energy efficiency 26 percent higher than
that of standard office buildings. The
building’s innovations earned it the city’s
first Gold LEED (Leadership in Energy and
Environmental Design) certification from the
U.S. Green Building Council.
The Hearst Tower’s striking “diagrid”
frame, which incorporates a system of steel
and glass triangles, floods the interior with
natural light while using approximately 2000
tons less steel than a conventional frame.
Most of the steel (90 percent) used in the
46-story, 80,000 m^2 (856,000-square-ft)
building is recycled.
Other energy-saving design features
in the Hearst Tower boost the efficiency of
the building’s heating and cooling systems.
Windows are coated to reduce solar
radiation, and heating and air conditioning
equipment cools and ventilates using only
outside air for three-quarters of the year.
In addition, embedded polyethylene tubes
within the atrium’s limestone floor circulates
water for both cooling and heating. Unique
to the building’s design, a 10-story waterfall
called the “Icefall” chills the atrium. The
Icefall’s water supply comes from rainwater
collected at the roof and drawn into a
53,000-L (14,000-gal) basement reclamation
tank. This water is also used to irrigate the
building’s plants.
Natural light is enhanced by the
placement of few internal walls and only low
partitions. Sensors turn off lights in empty
rooms and control the amount of artificial
light provided based on the natural light being
received.
Finally, building health is protected by
several interior features. Low-vapor paints
and low-toxicity sealants coat surfaces, while
furniture and carpet make use of low-toxicity
recycled content and materials obtained from
sustainable forests.
✓✓THE PLANNER
The Hearst Tower
in Manhattan offers
important contributions
to green architecture.
Energy Solutions: Conservation and Efficiency 463