Written on Dec 21, 2020
During the design of Forest Park High School’s renovation/addition, SEI’s design team reacted to the need for a central stair with a holistic solution to improve the project’s overall quality. Forest Park High School’s existing 4 story T-shaped plan had a dark core at its intersection. Existing stairs were adequate for egress capacity but remotely located at corridor ends requiring a central stair to improve circulation. A simple central stair would have required reframing the surrounding floors around a new 4-story stair shaft. SEI’s collaborative solution eliminated the entire floor plate of a single square bay on each floor within the existing steel superstructure, saving cost and tremendously enhancing natural light as part of developing viable next generation learning environments outside of the classroom.
The atrium required intense collaboration between Architectural, Mechanical and Fire Protection disciplines. Our design team coordinated with the City Fire Marshal’s office to devise a passive smoke evacuation solution. Smoke hatches were designed to fit between the existing joists in the roof requiring no structural modification. In addition to south facing clerestory windows, transparent smoke hatches would serve as skylights flooding the once dark central core with natural light down to the lowest level. The bank of entry doors was designed with automatic openers to permit relief air as the smoke is evacuated upward. The Mechanical Engineer developed a calculation package corresponding with the architectural code analysis demonstrating that the atrium could allow adequate smoke to accumulate above the highest level of egress while the early smoke detection system would trigger the smoke evacuation by simultaneously opening the roof hatches and the front doors. Prior to occupancy; the City Fire Marshal tested the installation with smoke canisters. The elaborate choreography between detection, mechanical, and architectural systems performed flawlessly permitting safe egress.
The bright atrium now serves as a light well providing full spectrum natural light to the once dark inner core. The vertical volume is a defining feature of the school providing both vertical circulation and a naturally lit collaboration space with amphitheater seating at its base.