Why some NYC buildings are more efficient than LEED-certified ones

Some of New York City's oldest buildings are more energy efficient than LEED-certified buildings.

Although the recently built 7 World Trade Center trumpets its LEED-Gold rating to lure renters, it isn't as efficient as the Chrysler Building, which was constructed in the 1930s.

While 7 World Trade Center gets an Energy Star score of 74 -- just below the minimum allowed for that certification -- the Chrysler building scores 84, thanks to extensive efficiency upgrades. The Empire State Building has a score of 80.

That's because old structures tend to have thicker walls, fewer windows and less ventilation. They also don't lend themselves to massive data centers that consume lots of electricity. 

It's also because of energy consumption by tenants. Tenants at the World Trade Center tend to be more data-crunching oriented with firms like Moody's, whereas nonprofits and other firms that require basic computing tend to occupy highly efficient buildings.

Not all older buildings score well, of course. The MetLife Building, built in 1963, scored 39, and the Seagram Building, built in 1958, scored 3.

Those numbers will change for Seagram, which will soon get extensive energy upgrades.

"Some scores will not be flattering, but identifying buildings with the most opportunity to improve is a big part of driving energy savings," Andrew Burr, a performance expert at the Institute for Market Transformation, told the New York Times. "It does put energy on the radar of real estate consumers."

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