What type of air movement does the Stack Effect describe?

The Stack Effect refers to temperature and buoyancy-driven air movement that occurs in buildings, particularly tall structures. It is based on the principle that warm air is lighter and will rise, creating a pressure difference within the space. When the air inside a building is warmed, it becomes less dense and rises, creating a lower pressure at the lower levels of the building and a higher pressure at the upper levels. This pressure difference can result in the movement of cooler air from the lower areas into the building, effectively causing a flow of air that is driven primarily by temperature differentials rather than external factors such as wind or humidity.

This phenomenon is critical for understanding natural ventilation, energy efficiency, and smoke control strategies in building design and safety protocols, especially during fire events. Recognizing how the Stack Effect operates helps in assessing air movement dynamics and implementing effective measures for smoke management and environmental control in high-rise buildings.