Building Physics of HVAC Interaction with Enclosure Systems and People

Many building types are designed, especially in the commercial office field, as a cold dark shell where interior tenant fit-out will occur later. Many aspects of the fit-out, such as final heating, ventilation, and air-conditioning (HVAC) system layout, partition wall locations, and the location of larger assembly spaces like conference rooms or other amenities, may not be fully defined at the same time as the core and shell. If tenant spaces are designed separately from the core and shell, the disconnect between the two designs may unintentionally impact the comfort of the interior space where it does not perform at a high level. As people utilize and move through the space, they are constantly being impacted by the building physics of the interior environment. This includes moisture and heat transfer across their skin. Clothing and footwear can impact a person’s overall comfort within the space based on how heat transfers through these and, in some cases, on moisture load within the space. System furniture, layout of structure, and HVAC system type and distribution can also affect a person’s comfort by adversely impacting the intended building enclosure performance. As the art and science of building design becomes more complex, it is necessary for designers to maintain a suitable proficiency in both these spheres and understand how different building systems interact. The wealth of scientific and technical data relating to the performance of buildings is one of contemporary architecture’s primary assets. This paper will cover the aspects of heat, air, and moisture transfer that impact our built environment and the interaction of HVAC with interior spaces, enclosure systems, and people. The authors will use examples from several projects to identify the concerns and practical solutions that can be implemented to improve a person’s comfort within interior spaces.