Silverstein gets the gold for 7 World Trade Center.

Designed with more efficient building systems that will conserve energy and water and deliver cleaner air to its tenants, 7 World Trade Center was given a gold LEED rating last week by the U.S. Green Building Council.

Speaking at the press conference for the event, which was held in the newly finished lobby of 7 WTC, Larry Silverstein, the developer and owner of the building, pledged that all the towers he develops on the World Trade Center site, beginning with the Freedom Tower next month, would meet or exceed 7 World Trade Center's standards. Silverstein also said that construction equipment on the WTC site would emit fewer emissions through the use of low sulfur fuels.

"We realized the enormity of protecting the environment," Silverstein said. "I've been an asthmatic all my life and I can tell instantly when the air is bad, I can't breathe. The atmosphere is precious."

While the Hearst Building and One Bryant Park are aiming to achieve similarly high LEED ratings as well, some observers applauded the fact that Silverstein brought such impressive environmental standards to a speculative office building. Both the Hearst Building and One Bryant Park have anchor tenants, a fact that SOM architects Nicholas Holt and Kenneth Lewis said better allows the developer to include green technology, which is often more costly than standard building systems.

7 WTC is being touted as an economical alternative to midtown space and there is no guarantee that tenants coming into the building will outfit their spaces with systems that match the building's levels of efficiency.

"I hope that executives around the country see the value of this building," said John Whitehead, the chairman of the LMDC.

Robert Watson, the director of international energy projects at the Natural Resources Defense Council and one of the founders of the LEED program, indicated that increased levels of productivity compensate for the costs of green space.

"You're going to have cleaner air and water in the buildings which means that employees will get sick less often and you'll also have a better work environment that will make employees want to come to the job," Watson said. "Even a lot of class A buildings in midtown are built with 1950s technology. People are really going to want to come into a building like this."

So far the 2.1 million s/f 7 World Trade Center has signed deals for almost 300,000 s/f of space.