
The red-wrapped stairway plunges infinitely as if you were looking into parallel mirrors. The stairwell is a focal point of United Therapeutics’ downtown campus in Silver Spring, Md. It is the largest net zero commercial building in the United States, and the tall space serves as a heat sink.
Stairwell designer: EwingCole, Philadelphia, www.ewingcole.com
Stairwell fabricator/installer: Shickel Corp., Bridgewater, Va., www.shickel.com
Metal wall/perforated panel fabricator/installer: MillerClapperton, Austell, Ga., www.millerclapperton.com
Stairwell walls: Trespa International B.V., Weert, the Netherlands, www.trespa.com





