The preservation of historic thermal environmental systems

The preservation of historic buildings is frequently dealt with at an aesthetic level, preserving the materials and visual attributes of a building within an assigned historical context. This approach to preservation often ignores the historic thermal environment, and as a result, many historic buildings are retrofitted with modern heating, ventilation, and air-conditioning (HVAC) systems. This paper argues that the preservation of environmental systems in historic buildings is critical to maintain a diverse building stock, and to preserve past practices of environmental control in order to educate a new generation of architects and engineers about the performance of passive and low-energy systems. Adapting methods from field studies of thermal comfort, this paper demonstrates that steady-state, predictive models of thermal comfort are not applicable to many types of historic buildings, using the urban arcade as a case example, and therefore, current static models of thermal comfort should not be applied to historic buildings with pre-existing systems of passive environmental control.