What is adaptive thermal comfort?

Overheating in buildings has historically been quantified by the number of occupied hours per year that the indoor temperature exceeds a particular temperature, irrespective of external temperatures. However, recent research has shown that comfortable room temperature changes with the external air temperature meaning that occupants are comfortable with higher room temperatures during warm weather. This is known as Adaptive Thermal Comfort.

A methodology for the assessment of Adaptive Thermal Comfort is presented in CIBSE Technical Memorandum 52 (TM52) “The Limits of Thermal Comfort: Avoiding Overheating in European Buildings”.

The TM52 assessment is based on comparison of room temperature with a maximum acceptable room temperature, which is calculated from the running mean of the outdoor temperature. The running mean used places greater weight on the temperature for days closer to the present as these have more influence on a person’s comfort temperature.