Credit: Blaine Brownell
New York's Empire State Building recently earned an Energy Star score of 80 out of 100.
A December article in TheNew York Times reported the discovery that older structures typically outperform new ones in conserving energy. While that may not come as a surprise to many architects—who know that historic buildings typically have thicker walls and smaller aperture sizes—the announcement apparently baffled many Manhattan-based building owners and developers.
Gerard Schumm, RFR Realty executive vice president and owner of the Seagram Building, claimed to have been "shocked" to find that his modern icon scored a lowly 3 on the 100-point Energy Star scale. And what of the 7 World Trade Center, a newly constructed, gold LEED-rated building? It received a 74—not even clearing the benchmark of 75 established for high-efficiency buildings by the federal program.
Fans of the famed Chrysler and Empire State Buildings, however, will be happy to note that these landmarks scored 84 and 80, respectively, due to recent mechanical and envelope upgrades (in addition to their more-conservative approaches to glazing).
Does this mean architects should apply historic approaches to cladding tall buildings? Not necessarily, although we must take into account all the factors that contribute to energy efficiency. Architects must look at a variety of methods for achieving improved performance, rather than simply mimicking early 20th-century (while avoiding midcentury) architecture. New glazing technologies, exterior shading devices, and the addition of second skins on existing buildings are a few examples that can deliver improvements. Nevertheless, it's clear that we can do better, especially since New York City generates 80 percent of its CO2 in conditioning buildings.
We must also consider the testing methods used to determine Energy Star (and other energy program) scores. For example, if one simply monitors how much energy a building uses, one can blame inefficiencies on the façade when there might also be significant interior lighting and equipment loads. Thus, as architects continue to refine approaches to designing high-performance structures, we must take into account the whole building and its comprehensive use.
We must also not forget occupant experience. For example, the 1970s energy scare inspired buildings with deep footprints, low ceilings, and inadequate access to daylight and fresh air. These structures might perform adequately on the Energy Star scale, but they can be debilitating places in which to work and live. The goal will be to find ways to minimize energy use while maximizing inhabitant livelihood—a challenge that will remain one of the highest goals of tall buildings for years to come, and offer a creative opportunity for the next generation of architects.
Blaine Brownell is a regularly featured columnist whose stories appear on this website each week. His views and conclusions are not necessarily those of ARCHITECT magazine nor of the American Institute of Architects.