Engineering a Phased Laboratory Exhaust Upgrade at the University of Maryland’s Frank S. Bressler Research Building

The University of Maryland, Baltimore recently upgraded the ventilation system in its Frank S. Bressler Research Building, a nearly 50-year-old medical school lab building that supports cancer research and other work. The building's original heat recovery and exhaust system, which pulls air out of labs and captures heat from it before it's exhausted, was due for replacement. Engineers redesigned the system to recover more energy and add backup capacity, while keeping the labs running the entire time, since shutting down research space wasn't an option.

To pull this off, the team used temporary fans to keep most of the normal airflow going on one exhaust line at a time while new equipment went in above the old units, riser by riser, across six main exhaust lines. Rooftop crane work had to be scheduled around medical helicopter traffic and satellite equipment on the roof. The finished system now moves 465,000 cubic feet per minute of exhaust air and recovers over 5.6 million BTUs per hour of heat from that air to warm incoming fresh air, cutting energy waste. The project also replaced aging pumps, heat exchangers, and piping for the building's hot water heating system.

This is a large institutional retrofit, not something that applies directly to a house. But it points to a broader idea relevant to any building, including a home: recovering heat from air that's being exhausted, rather than just venting it outside and losing that energy, is a proven way to cut heating and cooling costs. Similar heat-recovery ventilation systems, at a much smaller scale, exist for homes as well.