On the still-windowless edge of the 25th floor, the recently poured concrete floor has just hardened.
"We have high ceilings -- 9 feet, 6 inches -- and we'll have floor-to-ceiling windows. Everyone gets light."
The tower also will have glass inner walls, so that even people stationed near the core of the building will be able to look outside from their desks and check the weather. The constant sunlight will even help reduce heating bills.
Most skyscrapers have eight-foot ceilings -- and solid inner walls.
"There's a word that explains what we're doing: 'biophilia,'" Fox said.
The term "biophilia" was coined by Harvard biologist Edward O. Wilson to label an intense interest in and need for nature. Wilson says that humans have biophilia built into their DNA and that contact with nature is necessary for a general sense of well-being.
"People working at their desks will want to look outside, want to know is it raining out, or snowing … or sunny," Fox said of the building, which is scheduled to open in 2008.
The view isn't bad either: From one angle, inhabitants will look out past the Empire State Building, across the East River toward the Verrazano Narrows Bridge and the Atlantic Ocean. Another side offers views south across Manhattan rooftops and the mouth of the Hudson River toward the Statue of Liberty.
Fox and Durst are considering a "daylight dimming system" that would have light meters for each room that turn up ceiling lights only as much as needed.
They hope that such day-bright office surroundings and anti-claustrophobic high ceilings will help retain employees as the Bank of American chairman asked.
"There are studies that show that employees are 10 [percent] to 15 percent more productive if their surroundings are healthy and pleasant," Durst said.
And the benefits won't be limited to the building's occupants.
"We're actually acting as a giant air filter for New York City," said a subtly smiling Durst, his enthusiasm for the project shining through his understated soft-spoken manner.
"We will take in four times as much air as New York codes require, and the air we expel will be much cleaner than what we take in," he said.
The greater volumes of air make it possible to flush more VOCs (volatile organic compounds) out of the air, diminishing the likelihood of "sick building syndrome" sometimes blamed on imperfect air filtration systems.
He says that people working in the Bank of America Tower will breathe air cleaned of 95 percent of its particulate matter instead of the 35 percent typical in office buildings.
"The air ducts will be under the floor," Fox said. "Each office, each room, will have a thermostat to regulate however much air the occupant wants."
This will bring big power savings because air rising from the floor needs to be cooled down only to 65 degrees, rather than the 55 degrees needed for air coming from ducts in the ceiling where it has to get past the room's rising warm air and hot ceiling lights.
"Floor duct air systems were used by the ancient Romans," Fox said, "and they've been using them for 20 years in Europe. It's only just now starting to appear in the U.S."
The tower has three state-of-the-art natural gas fuel cells to create its own electricity, reducing the amount the owners have to buy.