News release: The new Physical Sciences Building at Cornell University in Ithaca, N.Y., has been awarded LEED Gold certification. Officially completed in 2010, the building earned 47 out of the possible 69 points. The building is equipped with sensors that increase or decrease ventilation based on whether the space is occupied. Air from office spaces is reused in lab spaces, as this air has been preheated or cooled. Finally, before being exhausted outdoors, a heat recovery system recaptures a portion of the heat , which is then used to temper the incoming fresh air. Other efficiency measures include a white roofing system, light-colored paving to reduce heat gain in the building and a rainwater-capture system for irrigation. In addition, the project site is an infill location: It shares walls with two existing buildings, improving thermal performance of both the older buildings by reducing exterior walls that can lose heat.