Landmark Battle Turns Green
Best fate for many energy-inefficient glass towers may be the wrecking ball.
Developers and other backers of a massive plan to rezone east midtown have a new and surprising arrow in their quiver: a green one.
A report by an environmental consulting group has concluded that the city's dozens of midcentury glass-sheathed skyscrapers, with a total of tens of millions of square feet of office space, are so wildly energy-inefficient that it would be better for the environment to bulldoze them and start over.
...According to the report, a building that is torn down can be rebuilt with 44% more square footage and still use 5% less energy. The bottom line is that the energy needed to tear down and rebuild a tower could be offset by energy savings from the new structure in 15 to 28 years.
"The tragedy of these [midcentury modern] buildings is that they can't be adapted," said Bill Browning, a co-founder of Terrapin Bright Green, the consulting firm that conducted the report, whose sponsors ranged from the New York State Energy Research and Development Authority, to architecture firm CookFox and the Real Estate Board of New York, the powerful landlords' group.
First off, the single-glazed curtain walls that represented the height of modernity in the 1950s were often cheaply produced and typically leak heat like a sieve. What's more, the structures are often too frail to support state-of-the-art, energy-efficient, double- or triple-glazed glass. While Lever House, the landmark glass-box office building at 390 Park Ave., was successfully retrofitted recently, it represents a rare exception. Built as a corporate headquarters in 1952, it was constructed to a far higher standard than many of the scores of nameless knockoffs that came later.
Outdated HVACs
Those cheaper glass towers frequently have outdated heating, cooling and ventilation systems, by which a constant volume of air is cooled and pumped into the building. If some offices need to be warmed up, the air-conditioned air is reheated. The report calls this system "analogous to driving a car with the accelerator pushed to the floor and controlling one's speed with the brakes."
...A prime example of the sort of energy-oozing building the report is addressing is the 47-year-old, 32-story glass box at 675 Third Ave., the first tower constructed by developer Douglas Durst after the Third Avenue El was torn down in the 1950s. The building is well-cared-for Class-A office space, has no mortgage and is about 80% full. It also has little in the way of exterior insulation.
"We'd consider tearing that building down if it made economic sense," said a Durst Co. spokesman.
The report concludes that it does indeed make sense. A developer could end up with a building that houses almost twice as many people by using space more efficiently—and demands about half the energy per capita.
Preservationists argue, however, that midcentury glass towers are the very definition of midtown.
"These buildings were incredibly interesting developments, built for the expectations of 1950s corporate America," said Simeon Bankoff, executive director of the Historic Districts Council. "They should be seriously considered for preservation."
Some of them are already protected, such as the Lever House and the 1958 Seagram Building, across the street on Park Avenue. Leaders of REBNY and other real estate industry groups have argued that it makes sense to preserve such masterpieces but not scores of unremarkable copycats.