Thermal comfort is more than just a indoor temperature

"Thermal comfort is the condition of mind that expresses satisfaction with the thermal environment and is assessed by subjective evaluation." (ANSI/ASHRAE Standard 55)

About thermal comfort*

Thermal comfort is a person's satisfaction with the climatic conditions within a built environment thus more complex than just a temperature. Actually, it depends as well on humidity, outdoor climatic conditions and the physiological and psychological state of a person. These individual parameters even change over time. Therefore, thermal comfort can difficultly be achieved with a constant temperature. Furthermore, being exposed to thermal neutrality, i.e. the range of temperature that a person perceives as neither too hot nor cold, hinders thermal comfort.
The general consensus emerging from the last two decades of thermal comfort research is that constancy in temperature may not be the optimum mode of control for building occupants and it may even be detrimental to thermal comfort.

Excessive Heating, Ventilating, Air Conditioning (in short: HVAC) energy demand in the built environment appears to be less a technological/economical challenge than a behavioural and psychological one. Continual enhancements in the energy efficiency of HVAC systems are steadily eroded by escalating thermal expectations of building occupants, i.e. constantly rising room temperatures.

Already 1976, Mower showed that thermal comfort is unattainable in environments where the body is in a neutral, steady-state heat balance with its environment, i.e. period during which the body keeps the same temperature. Therefore, a static temperature provided by classical control means such as thermostats is limited in its ability to provide thermal comfort to occupants.

Previous research focused on describing thermal comfort as satisfactory conditions for a statistical representative reference group. With nowadays new technologies it is possible to move to an individualized approach of thermal comfort.

*Statements based on research of Thomas Parkinson (PhD), Prof. Richard de Daer, Prof. Marcel Schweiker and others.