Last edited 27 Apr 2017

Thermal pleasure in built environments: physiology of alliesthesia

This article summarises a research paper 'Thermal pleasure in built environments: physiology of alliesthesia' by Thomas Parkinson & Richard de Dear published in 2015 in --Building Research & Information, 43:3, 288-301, DOI: 10.1080/09613218.2015.989662.

It is the second in a series exploring thermal alliesthesia in the context of indoor comfort.

It has long been recognised that our experience of thermal comfort is more complex than the steady-state heat balance adopted by many international standards which strive simply to achieve 'neutrality'.

As de Dear (2011) stated: If the very best that can be achieved in an isothermal, cool, dry and still indoor climate is 'neutral' or 'acceptable' for little more than 80% of a building's occupants at any one time, then the standards that have been set to date leave much to be desired.

The recent mainstreaming of 'adaptive comfort' begins to recognise the dynamic complexity of thermal comfort. However, 'thermal alliesthesia' goes beyond this, proposing that the hedonic qualities of the thermal environment (qualities of pleasantness or unpleasantness, or 'the pleasure principle') are determined as much by the general thermal state of the subject as by the environment itself. In its simplest form, cold stimuli will be perceived as pleasant by someone who is warm, whilst warm stimuli will be experienced as pleasant by someone who is cold.

The alliesthesia hypothesis suggests that non-steady-state environments where there are localised differences in skin temperature can create conscious experiences of thermal pleasure. The paper proposes that the alliesthesia concept is more complex than simple consideration of the relationship between core and skin temperature, and includes a spatial component. For example, we derive pleasure from wrapping cool hands around a warm mug.

The paper suggests that the concept of a one-size-fits-all approach to the provision of thermal comfort using centralised mechanical systems is flawed, and diversity in thermal preferences suggests criteria for evaluating comfort may need to be reconsidered. The implication is that standards for building services would focus more on providing the appropriate thermal conditions to the individual.

Non-steady-state thermal environments may give the potential to lift occupant satisfaction rates above 80%. To create instances of thermal pleasure, these dynamic effects need to be better understood, and solutions developed that excite the thermal sense and overcome thermal boredom.

Thomas Parkinson & Richard de Dear (2015) Thermal pleasure in built environments: physiology of alliesthesia, Building Research & Information, 43:3, 288-301, DOI: 10.1080/09613218.2015.989662

Read the full paper at Taylor & Francis Online.