Design comfort criteria, by definition, are related to an average person engaged in a specific activity within a defined environment. The terms average person or "user" are neutral and completely obscure differences amongst people. Settings and environments in which office workers feel most comfortable are as varied as their individual physiologies, thus making environmental design difficult. However, there is broad agreement among researchers that individual comfort and satisfaction can be attained by providing individual control of the local environment.
The perception of being in control appears to be as important as having comfortable conditions. Perceived control depends on the presence, design and placement of control devices, but also on the overall effectiveness of control strategies, the attitudes and actions of the management and the way in which physical and human management systems operate together.
Despite such advice, designers continue to build essentially static buildings that are centrally controlled and unable to be fine tuned by individual users. These buildings produce environments of moderate quality that can leave a percentage of the occupants dissatisfied and sometimes ill. We continue to use the design standards which knowingly are unable to respond to 20-30% of the building’s population in terms of environmental comfort and well-being. The design challenge lies in integrating the users’ priorities with energy efficient control, so that their actions are coincident with behaviour that conserves energy.