The International Building Code defines institutional occupancies under Institutional Group I and includes the use of buildings or structures where care or supervision is provided to persons who are or are not capable of self-preservation without physical assistance. It also includes facilities that house persons who are detained for penal or correctional purposes and/or those whose liberties have been restricted.
VRF systems are direct expansion heat pump systems in which multiple indoor units are connected to a common condensing unit, which can be either air or water source, via a refrigerant piping network. These systems have become popular in North America in the last 10 years and are often applied to less complex institutional occupancies. In this article, we will review the basics of VRF systems and highlight some considerations for applying these systems to Group I occupancies. Specifically, we will examine considerations for heating redundancy, the requirements necessary to meet ventilation and airflow requirements, and compliance paths for ASHRAE Standards 15 and 34.