Using natural daylight to illuminate your building is a free, healthy, productive and sustainable use of the sun. According to the U.S. Green Building Council, daylighting helps, “connect building occupants with the outdoors, reinforce circadian rhythms, and reduce the use of electrical lighting by introducing daylight into the space.” There is much for information about daylighting in the Occupant Productivity section of the Building Owner’s Toolkit, but perhaps the most compelling reason to integrate more daylighting into your building is that it’s free and produces no carbon emissions.
Also known as “daylight harvesting,” daylighting can be achieved using a number of technologies, including automated window shades, skylights, reflective interior paints, light tubes, light shelves, electrochromic and thermochromic glass, and more. The National Institute of Building Sciences offers an online course to help you better understand the different technologies used for daylight management.
If you are constructing a new building, making sure that the building orientation is properly aligned with the sun can drastically improve your building’s ability to harvest daylight. According to the U.S. Department of Energy, “South-facing windows allow most winter sunlight into the home but little direct sun during the summer, especially when properly shaded. North-facing windows admit relatively even, natural light, producing little glare and almost no unwanted summer heat gain. East- and west-facing windows provide good daylight penetration in the morning and evening, respectively, but may cause glare, admit a lot of heat during the summer when it is usually not wanted, and contribute little to solar heating during the winter.”