Table 6.
Gaps in knowledge of daylight research related to environmental factors.
| Impact of latitude, time zones, climate | |
| Seasonal changes | Does exposure to seasonal changes in day length have consequences for human physiology and health, as some of the existing literature suggests [79,111,207,208]? |
| Latitude | In those most vulnerable e.g., living at high latitudes, light therapy and improved home/work lighting has been shown to be useful for winter depression and sleep disorders, given that there is insufficient daylight for some months of the year [209,210]. |
| Location within time zone | Does the location within a time zone modify daylight’s effect on an individual’s circadian phase [208,211]? |
| Daylight saving time (DST) | Is there a long-term effect of daylight saving time [212,213,214,215] on wake and sleep physiology? |
| Micro/macroclimate | How does ambient temperature, humidity, and air pollution modulate daylight’s effects on physiology? |
| Rural vs. urban environments | Is there a difference in daylight exposure dose between those living in rural vs. urban environments? |
| Architecture, urban design | |
| Daylight conditions in buildings | What role do the complex daylight conditions in buildings, such as building orientation, window positioning, glazing, play on visual comfort/adversity (glare), productivity and performance, circadian entrainment and health in general [32,216,217]? Could architecture be deployed to accentuate spatial-temporal modulation of daylight to stimulate retinal photoreception? |
| Glazing | How do single vs. double vs. triple glazing systems, electrochromic windows, and new technologies such as smart windows with integrated micro-daylighting systems influence health [218]? How effective is dynamic glazing in order to address heat emission and light? |
| Floor orientation, spatial distribution of daylight | How does the location of apartments (floor and geographical orientation) within a given building, and the indoor spatial distribution of daylight, affect human health? |
| Daylight enhanced qualities | What design can provide daylight-enhanced qualities in single buildings and urban settings? |
| Complementation with electrical light/daylight systems | How can the geographical orientation of a building, which determines its indoor light intensity, be compensated/complemented with daylight systems/electric light? |
| (Day-) light control systems | How should modern (light) sensor and controller technology be used to support health, performance, and well-being of its inhabitants? |
| Self-control of (day-) light | How much self-control over sensor control is necessary and desired [219]? |
| Alienation from nature | What are the consequences of losses of daylight/weather/seasonal effects due to urban densification, loss of daylight recreation areas, daylight restriction due to high buildings etc. on mood, health and quality of life [69,220,221,222,223]? |
| Role of view | Low daylight exposure and daylight deprivation usually also means deprivation from a view. This could have additional and far-reaching negative consequences, although research to date is scarce [223]. |