Project Overview
GPJ were appointed to design the replacement of an existing rooftop Air Handling Unit (AHU) serving general areas within a six-storey hospital building. The existing system had no heat recovery and suffered from high ductwork resistance due to a convoluted supply air route, resulting in increased fan energy consumption and inefficient operation.
Our Involvement
GPJ undertook the mechanical design for the replacement AHU, associated ductwork and ventilation ancillaries, including the BMS control strategy. The design incorporated a new roof penetration directly into the existing service riser, significantly simplifying the supply air route and reducing system resistance.
New extract ductwork was designed back to the AHU to provide heat recovery in accordance with current healthcare ventilation requirements. GPJ also provided technical support throughout construction, attended regular project meetings and witnessed key commissioning activities and BMS controls against the design requirements.
Key Project Considerations
The project focused on improving the energy efficiency and performance of the existing ventilation system while integrating new plant into a live hospital environment. During the works, an existing slam-shut fire damper that had failed in the open position was identified and replaced with new motorised smoke and fire dampers connected to an addressable fire damper control panel.
The completed installation significantly reduced ductwork resistance, introduced heat recovery and improved the overall control and resilience of the ventilation system. The project was completed on programme and within budget.