By Katherine Gloede

Blurring sometimes rigid boundaries between indoors and outdoors is key to biophilic design. Maximization of natural light, or daylighting, is a key ingredient ripe with obvious benefits and unique opportunities. Natural light reduces daytime energy use and fulfills our inherent attraction to affiliate with nature. This particular connection with the outdoors improves our circadian rhythm and brain function.

A the University of Copenhagen, the Green Lighthouse uses daylighting to reach carbon neutrality. Completed in 2009, the student and faculty center is cylindrical, allowing sunlight to penetrate glazing at different angles throughout the day. At the building’s center, a long spiral staircase is bathed in sunlight from dawn until dusk. Solar shading ensures that, while light disperses, the building is not overheated during summer.

Beyond reduced energy dependence, daylighting with angular intentionality puts ancient knowledge to use—our foremost calendar and timepiece is the sun.

Around the same time the Green Lighthouse was built, architects Carrie and Kevin Burke designed their Charlottesville, VA home as a sundial. Dubbed the observatory, the living room directs sunlight through a rooftop oculus. Not only does this connection with outdoors tell time, but it celebrates important dates. Utilizing changes in the angle of solar radiation throughout the year, the Burkes placed metal-filled incisions in the floor to signify the equinox and solstice as well family birthdays.

A similar feature is incorporated at a much grander scale in architect Santiago Calatrava’s newly opened transportation hub in Lower Manhattan. The World Trade Center Oculus connects the City’s subway system and New Jersey PATH trains with added retail space. The station’s roof is an arrangement of steel ribs and retractable skylights connects the underground terminal with the world above.

World Trade Center Oculus (Photo: Sara Healey)

Calatrava’s creation also employs sunlight beyond the basic principles of daylighting. The entire station is positioned neither perpendicular nor parallel to the City’s street grid. Its unique angle captures uninterrupted sunlight at 10:28AM every September 11th, when the second tower fell in 2001. The “wedge of light” concept, formed by the skylight where the two sides of the steel cage exterior meet, is one of very few design elements that followed the project from first proposals to final construction. A naturally occurring memorial is ingrained in the design.

World Trade Center Oculus (Photo: Sara Healey)

Like the Burkes’ home, the WTC Oculus uses the sun as energy and a timepiece. It is a subtle, but profound commemoration. Connection with Earth’s natural process is coupled with connection to each other.