Temperature variation in centrally controlled HVAC buildings and its impact on comfort and performance

New buildings are often designed to deliver more or less steady thermal indoor environments. This is especially true for centrally controlled buildings that are fully air-conditioned. Allowing some daily drifting of the indoor temperature with (momentary) outside temperature will result in energy savings, also in 'HVAC buildings'. Therefore the following questions were asked: How do hour-to-hour temperature changes affect health and thermal comfort of building occupants? And what are the effects of temperature drifts and ramps on the performance of building occupants? The conclusion was that there are indications that allowing for (smart) temperature variations can be beneficial in terms of comfort. However so far no studies on e.g. health and performance effects of hour-to-hour temperature variations are discovered. A set of research questions is presented. One of those is: 'What would an ideal (minute-tominute) temperature control algorithm look like in a centrally controlled HVAC building that optimises (simultaneously) occupant comfort, occupant performance and energy use? Future research is described that should allow for answers to that important question.