Business School Clears the Air

CHALLENGE:Washington University connected two adjoining buildings at the heart of the Olin School of Business with a five-story glass atrium as the centerpiece of a $65M renovation. What had been a shared, open courtyard would now be enclosed space, requiring ventilation and smoke controls. The geometry of the structure would essentially trap smoke in the event of a fire. Maintaining unbroken space and allowing natural light to filter through the atrium and illuminate all five levels below is one of the most welcoming design aspects. INFLUENCE:Passive natural ventilation has been a common European design practice for decades, and highly advanced products have been developed over the years to support this building practice. SOLUTION:Because building fire protection code (NFPA92B) allows for natural ventilation as a means of smoke control, a mixed-mode system was proposed, combining natural and mechanical ventilation—though the smoke control system would be entirely passive. The architects and the structural engineering company worked together to specify architectural-grade ventilation products, including glazed natural ventilators for the roof. A combination of doors, windows, and ventilators work in concert to allow cool air to enter the atrium space at low levels. As warm air rises, it exits through high-level ventilators from Bilco at the top of the space. The large difference in height between the low-level entry of fresh air and the exit of warm air through the atrium creates a large buoyancy effect that draws air through the building. The upward airflow and circulation creates a cooler, more comfortable indoor environment and an ideal path for smoke extraction. As an added benefit, a mixed-mode solution such as the Olin School’s put-in-place can also accommodate the concept of nighttime purging. null