Something surprising has happened with many so-called “sustainable” buildings. When actually measured in post-occupancy assessments, they’ve proven far less sustainable than their proponents have claimed. In some cases they’ve actually performed worse than much older buildings, with no such claims. A 2009 New York Times article, “Some buildings not living up to green label,” documented the extensive problems with many sustainability icons. Among other reasons for this failing, the Times pointed to the widespread use of expansive curtain-wall glass assemblies and large, “deep-plan” designs that put most usable space far from exterior walls, forcing greater reliance on artificial light and ventilation systems.
Partly in response to the bad press, the City of New York instituted a new law requiring disclosure of actual performance for many buildings. That led to reports of even more poor-performing sustainability icons. Another Times article, “City’s Law Tracking Energy Use Yields Some Surprises,” noted that the gleaming new 7 World Trade Center, LEED Gold-certified, scored just 74 on the Energy Star rating — one point below the minimum 75 for “high-efficiency buildings” under the national rating system. That modest rating doesn’t even factor in the significant embodied energy in the new materials of 7 World Trade Center.