The tower has several design features that are intended to meet green building standards as part of the Leadership in Energy and Environmental Design (LEED) program. The limestone-clad floor slabs of the atrium and office floors contain polyethylene tubes that can carry heated or chilled water to regulate temperature and humidity. A tank in the basement collects rainwater from the building's roof, some of which is pumped through "Icefall" in the lobby. The furniture and lights were also designed to be energy-efficient. Two executive stories have daylight dimming systems, which dim when there is sunlight, while the other office stories have daylight switching systems, which turn off when there is sunlight. Furthermore, about 85 percent of the material from the old building's interior was recycled for use in the tower's construction.