Museum Conservation: Preserving More Than Art

It can take a lot of energy and sophisticated building systems to conserve art. Artwork is fragile, and humidity, temperature and light must be maintained at optimal levels in order to preserve it. For these reasons, art museums have never been all that sustainable. To complicate matters, contemporary museums often have elaborate architectural forms commensurate with their impressive collections that, at first glance, may seem to focus on built form rather than practical concerns like energy conservation.

Today, however, as museums build anew, renovate, or expand, museum administrators are taking the opportunity to go green. These cultural institutions are using state-of-the-art technologies not only to preserve their collections, but also to achieve ambitious sustainability goals.

For a museum to be sustainable, the key is the efficiency of its mechanical, electrical, and plumbing (MEP) systems. If a museum’s MEP systems are designed well, its energy usage can be reduced without sacrificing its need to maintain the valuable artwork on display or in storage. Three museums — the Isabella Stewart Gardner Museum (ISGM) in Boston, the Parrish Art Museum in Water Mill, New York, and Crystal Bridges Museum of American Art in Bentonville, Arkansas — are all very different institutions, but they successfully overcame the same challenge: how to make the eye-popping architecture sustainable while preserving great art.

ISGM, for example, is an urban museum that needed to expand and also preserve its original 100-year-old palazzo. It is on track for LEED Gold certification. To complement the museum’s aspirations for sustainability and reduce the ecological footprint of the 70,000-sq.-ft. extension, engineering firm Buro Happold designed a system of 1,500-ft.-deep standing column geothermal wells (the equivalent of eight Empire State buildings standing end to end), which are linked to heat pumps that heat and cool the building. This kind of system is rare for an art museum. Additionally, the engineers found a creative solution to the constricted urban site by integrating the large mechanical elements into a two-level basement, which provided space for the equipment and made the system feasible. The result is a geothermal system that reduces energy consumption by an estimated 25 percent.

In addition to the ground-source heat pump system, the engineers designed the air conditioning systems to minimize wasted energy by tightly controlling the temperature and humidity of the zones in which there are visitors and artwork. For example, the new Special Exhibition Gallery has a 36-ft.-high movable ceiling, but the air quality of only the lower two-thirds of the space (where artwork is hung and people circulate) is tightly controlled.

Yet another institution that is building larger premises for its collection is the Parrish Art Museum; the original museum is a complex of 19th- and 20th-century buildings, while the new 34,500-sq.-ft. building currently under construction is designed by architects Herzog & de Meuron. Buro Happold took a cue from local buildings by using an open loop geothermal well system that provides the heat source and heat sink for a series of heat pumps that supply heating and cooling to the building. Open loop well systems like this one are in fact the most energy efficient means of connecting heat pumps to ground water in order to provide heating and cooling.

Parrish’s open loop system takes ground water from a series of relatively shallow suction wells on the 14-acre site and passes it through the building’s heat pumps before transferring the water to a separate series of diffusion wells over 150 feet away. To further reduce energy use, the engineers designed the gallery spaces to utilize an under-floor ventilation system. This type of system offers tight control of the temperature and humidity, and saves energy and costs by introducing conditioned air through floor grilles at low velocity in the occupied zones. Since the mechanical ducts are concealed, they don’t disturb the ambiance of the galleries.

The rural Crystal Bridges Museum of American Art, designed by Safdie Architects is probably one of the most ambitious museum buildings in recent years; the galleries are “hanging bridges” suspended over a system of ponds. Because the building forms were uncommon, the 201,000-square-foot facility required special attention from the engineers to design MEP systems that would simultaneously preserve the artwork, keep visitors comfortable and limit the museum’s impact on the surrounding environment. To make sure the systems would meet the goals of the museum, Buro Happold used computational fluid dynamics to study the air velocities and temperatures in the different gallery spaces throughout the year. They then used that information to design effective heating and cooling systems for the buildings.

Because each bridge has expansive glass walls for direct contact with the natural setting and daylight, the artwork is hung within gallery “boxes” set a few feet back from the glass. The engineers employed an innovative “buffer zone” strategy to control the temperature and humidity in the gallery “box” spaces apart from the overall bridge spaces. The bridge zones act as buffers to prevent condensation, extreme temperatures, and/or excessive humidity from affecting the art in the central gallery “box” spaces. The buffer zones make it easier to control the climate within each bridge structure, and reduce the energy usage of the systems.

Now that museums can maintain a high degree of operational control while lowering their overall energy use, environmentally responsible institutions are fast becoming more common.

Known for years for preserving and maintaining impressive collections, museums may also become recognized for being good stewards of our environment.