The craft of monument lighting design

Washington is a spectacle at night. Glittering buildings highlight the skyline, drawing residents and tourists alike to the capital. Most visitors enjoy the monuments that line Constitution Avenue during the day, but when the sun goes down, a spectacular scene emerges thanks to monument lighting design. 

The effects are not easy to create, however. Architects and lighting designers face a number of challenges when lighting monuments. Will the light ensure the monument is depicted as the artist intended? Will non-traditional lighting design be necessary?

For example, 555-foot Washington Monument’s tall, slender design makes it difficult to light in a uniform way. The pyramid-shaped capstone at the top creates a natural shadow when the monument is lit from below. (Jackie Craven)

For many years, lighting aimed individual light sources directly onto the sides and up to the top of the monument. This method, however, created uneven illumination, especially at the pyramid level. Also, because of the illumination angle, only 20 percent of the light actually reached the surface of the monument, while the rest dissipated into the night sky. (Jackie Craven)

When designing lighting for monuments, it is important to evaluate the setting of the monument in relationship to other visible structures and to create a hierarchy of importance. Illumination of a monument can be achieved in multiple ways, and these methods each provide a variety of choices. Understanding how these options work together is critical in creating an effective monument lighting design.

Following are three illumination methods that can be effective in monument lighting design:

• External illumination – Use light fixtures mounted on the ground or from above that cast light upon the monument structure.
• Internal illumination – Install illumination devices (LEDs or LED lamps) inside a sign cabinet or channel letter that sends light outward to the viewer through a variety of sign face, back and return fabrication processes. 
• Passive illumination – Use special reflective materials that do not require a direct power source to make the monument appear as if it’s illuminated at night. (Matt Chaeboneau)

Using these techniques, in 2005 experts tackled longtime challenges and improved illumination of the Washington Monument. They designed a new system for the monument that is more energy efficient and includes fixtures that focus the light with mirrors, or passive illumination.

• Instead of trying to light a tall structure from the ground up, mirror optics direct light 500 feet from the top down.
• The lower levels are illuminated with 66 150-watt fixtures at the base of the monument.
• The 12 mirrored corner fixtures are located on four 20-foot high poles, 600 feet from the monument. (Jackie Craven)
• The elimination of nearby lighting vaults at ground level increased security and diminished the problem of nighttime insects near the tourist attraction. (Jackie Craven)

Today, nighttime visitors to the Washington Monument see a more uniform, three-dimensional structure.

This is just one example of the many memorials and monuments that take on a new persona during the evening. But creating ambiance can sometimes be tricky, even for the most experienced lighting designers. Sensitivity to detail, innovative techniques and an awareness of the surroundings all assist in shaping thoughtful, effective monument lighting design.

Sources:

1. Jackie Craven, "Lighting Design for the Washington Monument" (July 01, 2017)
2. Matt Chaeboneau, "Mastering Monument Sign Illumination" (April 21, 2015)