Occupants are often unaware of window opening strategies that can enhance their well-being and reduce energy consumption. Window feedback systems that indicate when to manually operate a window have become a strategy for enhancing the indoor climate, occupant’s satisfaction and energy efficiency. These systems are recognized for providing the comfort benefits of manual window controls while providing the efficiency benefits of completely automated windows (Bordass et al., 2007; Day et al., 2020). However, there is a lack of evidence to what extent window feedback systems are able to provide a successful cooperation between occupants and windows which enhances energy efficiency, satisfaction levels and their well-being.

This research investigated the influence that ambient light window feedback systems can have on the indoor climate and occupants’ satisfaction in open-plan workplaces. The research focused on determining the effectiveness of these systems and on establishing design guidelines for further developments. To do so, an experiment was carried out which assessed an existing and new situation of an open-plan workplace. The existing situation served as a benchmark for the new situation in which an ambient light window feedback system was implemented.

The methodology is divided into two parts and consists of literature research and research by experimentation. The literature research formed the initial part of the study and provided important considerations for the experiment. In addition, it formed guidelines for designing the window feedback system. The research by experimentation part provided objective and subjective data to determine the effectiveness of the implemented window feedback system. In addition, the data helped in determining design recommendations for the further development of the window feedback system and its algorithm. The outcome of the research shows that ambient light window feedback systems can be promising inside open-plan workplaces.

Occupants are often unaware of window-opening strategies that can enhance their well-being and reduce energy consumption. Window feedback systems that indicate when to manually operate a window have become a strategy for enhancing the indoor climate, occupant’s satisfaction and energy efficiency. These systems are recognized for providing the comfort benefits of manual window controls while providing the efficiency benefits of completely automated windows (Bordass et al., 2007; Day et al., 2020). However, there is a lack of evidence to what extent window feedback systems are able to guide occupants towards an effective window operation for both energy and comfort. This research proposes a new window feedback system based on indoor air quality, thermal quality and energy performance. Results from a preliminary testing and deployment are also presented to investigate the effectiveness of the light window feedback system. The outcome of the research shows that ambient light window feedback systems can improve the indoor environment and occupant’s satisfaction in open-plan workplaces. Objective measurements reveal an improved indoor temperature, relative humidity and CO2 concentration. Furthermore, it shows a reduced ineffective window opening time by 55%. Subjective measurements reveal that a majority of the respondents understand the system, do act according to the provided feedback and were satisfied with the implementation. The outcome of this research provides also design requirements for the further development of the light window feedback system and its algorithm.