Interesting conclusion from Ph.D. Thesis by Atze Boerstra on “Personal Control over Indoor Climate, Impact on Comfort, Health and Productivity”
Office workers often have no or limited possibilities at their workplace to control their indoor climate. They nowadays frequently are exposed to environments deprived of operable windows, adjustable thermostats and other opportunities to fine-tune their local air quality and personal thermal environment according to momentary needs. When office buildings are (re)designed personal control over indoor climate and adjustability of facades and HVAC systems are apparently not always high on the agenda. This probably is due to a lack of knowledge in terms of personal control related mechanisms amongst relevant decision makers (principals, architects, consultants etc.) and amongst building scientists in general.
The core research objectives of “Personal Control over Indoor Climate, Impact on Comfort, Health and Productivity”
- to examine relationships between availability and quality of HVAC/building related control devices in office buildings and perceived control over the indoor climate;
- to examine relationships between perceived control over the indoor climate and comfort and satisfaction of office workers;
- to examine relationships between perceived control over the indoor climate and health of building occupants, specifically the incidence of building related symptoms (SBS);
- to examine relationships between perceived control over the indoor climate and (self-assessed and objectively measured) performance and (self-assessed) sick leave of office workers.
Conclusion on “Personal Control over Indoor Climate, Impact on Comfort, Health and Productivity”
The combined outcomes of the database analysis, the field study and the laboratory study support the hypothesis that control (having or not having control) over one indoor climate alters one’s reactions to that indoor climate. The mechanism involved was not totally explained but, overall, the combined studies imply that investing in effective and usable indoor climate controls will enhance perceived control over the indoor climate. Enhanced perceived control also improves office workers’ satisfaction with their thermal environment and the indoor air quality at their workplace. It also increases overall comfort perceptions. The results related to the productivity effects (both self-assessed and objectively measured productivity effects) were rather inconclusive. Also the results in relation to the incidence of building related (SBS) symptoms were somewhat inconclusive.
As modern office buildings become more and more open plan offices of the future, where workers may not have a fixed designated work station, in many instances, will ask for more than just standard controls like operable windows and adjustable thermostats. Recent developments in the form of personal ventilation systems and local climate control systems integrated in office furniture seem to open up promising alternative routes towards better adjustable indoor climates in offices.
This PhD study revealed that personal control over indoor climate is a complex phenomenon that involves many aspects. The conceptual model was partly validated but some mechanism-related questions remain unanswered. To better understand how office workers use controls and to understand how building occupants’ perceptions about their indoor climate are influenced by the presence and use of these controls, it is necessary to look beyond the traditional borders of building science and indoor climate research. Further research is needed in close cooperation with environmental psychologists and other social scientists to explore in more detail how control over one’s indoor climate affects comfort, health and task performance.