Recent research revealed that an estimated $11M in energy cost is wasted annually due to open vents at the tops of tall buildings. The vents are code-mandated but are left open, allowing tall buildings to become chimneys in winter. A NYSERDA study report published by Urban Green Council quantified the energy impact and recommended retrofits to halt the airflow escaping from elevator and stairwell shaft vents. This session will discuss the benefits of closing these vents, the enabling code change in NYC, and the recommended retrofit options to achieve enduring savings in tall buildings.