Daylight and view through residential windows: effects on well-being

The discovery of intrinsically photoreceptive retinal ganglion cells (ipRGCs) in 2001 was a great leap forward in photobiology, and ignited strong interest in the possibility of using light exposure to improve health and well-being. CIE in 2004 promulgated five "principles of healthy lighting", and proposed that these principles should lead to a renewed emphasis on architectural daylighting because daylight is rich in the short wavelengths and bright at the times of day that seem most important to circadian regulation. The science has moved rapidly in the ten years since the last substantive reviews of the state of the art on the health and well-being effects of daylight and windows, making it time for a renewed examination of the literature. There has never been a thorough review that focused on residential windows, so our review has focused on that application. This conference paper will briefly report on the review and summarize the research questions that we think are most urgently in need of answers.NRC publication: Ye

On the influence of building design, occupants and heat waves on comfort and greenhouse gas emissions in naturally ventilated offices. A study based on the EN 15251 adaptive thermal comfort model in Athens, Greece

According to the Intergovernmental Panel on Climate Change the buildings sector has the largest mitigation potential for CO2 emissions. Especially in office buildings, where internal heat loads and a relatively high occupant density occur at the same time with solar heat gains, overheating has become a common problem. In Europe the adaptive thermal comfort model according to EN 15251 provides a method to evaluate thermal comfort in naturally ventilated buildings. However, especially in the context of the climate change and the occurrence of heat waves within the last decade, the question arises, how thermal comfort can be maintained without additional cooling, especially in warm climates. In this paper a parametric study for a typical cellular naturally ventilated office room has been conducted, using the building simulation software EnergyPlus. It is based on the Mediterranean climate of Athens, Greece. Adaptive thermal comfort is evaluated according to EN 15251. Variations refer to different building design priorities, and they consider the variability of occupant behaviour and internal heat loads by using an ideal and worst case scenario. The influence of heat waves is considered by comparing measured temperatures for an average and an exceptionally hot year within the last decade. Since the use of building controls for shading affects thermal as well as visual comfort, daylighting and view are evaluated as well. Conclusions are drawn regarding the influence and interaction of building design, occupants and heat waves on comfort and greenhouse gas emissions in naturally ventilated offices, and related optimisation potential.<br /