As those who work in the field know, old buildings can also be sustainable buildings. A LEED green building certification is often associated with modern new office towers, but in fact, some of our oldest structures benefit the most from sustainability upgrades. Increasing energy efficiency and reducing carbon impact is an imperative in today’s world, but preserving the unique architectural features of historic buildings, and their cultural context, does not have to take a hit as a result. Also, many older buildings have lasted as long as they have because they were built with sturdy materials that stand the test of time—an inherently sustainable quality.

Keeping our older buildings in use makes sense from the standpoint of sustainability—but it is also important because of their value as markers in our communities. Careful preservation ensures that the places from our past that have cultural value continue to support future generations. LEED projects cover many diverse styles and uses. The following three historic buildings, ranging from the 15th century to the 1920s, all serve as places of learning for their communities, just as they did in years past.

Fay House, 1807 (Cambridge, Massachusetts)

The oldest building in the United States with a LEED certification, Fay House was built in 1807 as a private residence. Beginning in 1885, it served as the first permanent building for Radcliffe College, an early higher education institution for women and one of the historic "Seven Sisters" colleges of the Northeast.

Now part of the Radcliffe Institute for Advanced Study at Harvard University, the Fay House renovation called for use of the LEED for Building Design and Construction rating system, where it achieved a Gold-level certification. Green updates like geothermal energy, occupancy sensors, and use of salvaged materials were combined with facade restoration and accessibility features to bring the historic integrity of the structure in line with 21st-century needs.

As part of a Cambridge historic district, the project was subject to review by the Cambridge Historical Commission. Although it was not required to be reviewed for Secretary of the Interior’s Standards, the standards were followed in rehabilitating the building, according to Venturi, Scott Brown and Associates, the architecture firm involved.

Kate Loosian served as the project manager for the Fay House certification and is now the director of facilities management at Harvard Radcliffe Institute. According to her, the team faced two related issues in preserving the building’s historic character.

The first was “the inherent challenge of restoring historic spaces while designing and renovating for modern institutional office and meeting use,” says Loosian. “The first two floors of Fay House were built as a family residence in 1807. Even the additions made during the Radcliffe College years reflected uses from a different time and purpose. Bedrooms and old library spaces do not necessarily make great offices. However, it was also a wonderful opportunity to restore some of the glorious spaces that had been subdivided in prior renovations.”

The second challenge was fitting modern systems into a historic structure originally built to be heated by fireplaces and lit by candles. “We needed fan coil units and their piping, controls, lighting, life safety systems, an elevator, and A/V systems,” says Loosian. “Coordinating and concealing all the infrastructure that supports modern amenities and expectations was an enormous undertaking.”

One of the advantages of the site, though, was pockets of existing infrastructure. For example, for heating and cooling, the team was able to use geothermal wells that had originally been installed for an adjacent building.

Another benefit was the daylighting and views provided by a building originally designed with plentiful residential windows. “This was a LEED credit that capitalized on the building’s origins,” says Loosian. “Utilizing daylight harvesting and occupancy sensors, we made a notable impact on our energy use for lighting, as well as plug loads.”

Loosian encourages green preservation professionals to honor the existing historic structure of their projects. For Fay House, the design and construction teams were dedicated to retaining as much of it as possible. “We managed to keep much of the bones and finishes of the original building, and we sourced far fewer new materials by prioritizing reuse,” says Loosian.

“This building is a physical reminder of the fascinating history of Radcliffe,” she says. In the 19th century, Radcliffe College was founded to ensure education opportunities for women at a time when they were not allowed to attend Harvard College. The first dean of the institute, Drew Gilpin Faust, later became the first woman president of Harvard University, bringing the history full circle.

“Today, Harvard Radcliffe Institute is one of the world’s leading centers for interdisciplinary exploration, and Fay House is not only an exemplary sustainable building, but also the hub of our leadership and administration,” says Loosian. “I personally love that the institute leans into the future by standing firmly and proudly on the foundation of our past.”

Sede Centrale Ca’ Foscari, 1453 (Venice, Italy)

Overlooking the Grand Canal, the Venetian Gothic palazzo Sede Centrale Ca’ Foscari claims the title of oldest LEED-certified building in the world. The name means “headquarters,” for which the structure serves for a modern university. Built in 1453 by Francesco Foscari, the doge of Venice at the time, Palazzo Foscari became in 1868 the seat of the Royal School of Commerce—what is today Ca' Foscari University of Venice. The building is certified under LEED for Operations and Maintenance, the rating system option for existing structures.

As part of the historic city center and a UNESCO World Heritage site, Sede Centrale is subject to restrictions that ensure preservation of its historical, cultural, and artistic value, says Gabriele Rizzetto, general director of Ca' Foscari University.

To preserve the special characteristics of a half-century-old landmark, all sustainable upgrades and maintenance must follow certain guidelines. Photovoltaic systems are not allowed on the roofs of any Venetian building, and green roofs are also prohibited.

Though this presented a challenge, the project team got creative to increase energy efficiency in a less visible way. At Palazzo Foscari, careful architectural assessments were undertaken to locate the heating and cooling systems in a way that was “discreet and organic,” according to Tiziano Pompele, manager of real estate and purchasing area. The team installed systems inside the building in particular “ad hoc areas” to avoid disrupting the exterior of the building.

Underground spaces outside the building were carved out for hot and cold running water systems and sewage treatment. The attic served as a location for cooling towers so that they would not be visible from the outside. Inside the building, vertical air shafts were created for the passage of the pipes to limit the need for false ceilings and air pipes, says Pompele.

LEED credits with which the project achieved strong results included Sustainable Sites and Alternative Commuting Transportation. Heat Island Reduction credits were achieved because of the high-albedo materials used as roof coverings.

Existing comparative data helped the project team. The university had already been monitoring emissions and energy consumption, which “enabled us to [use] this information for certification purposes,” says Massimo Mion, director of the building management office.

Serving as an example for similar future projects is a side benefit of achieving LEED certification. “Palazzo Foscari is the most iconic building in the university,” says Martina Gonano, director of the Ca’ Foscari sustainability office. “Ca' Foscari can therefore be a stimulus to the local community … as an important case study with respect to the ecological transition that everyone will have to implement in the coming years.”

African American Library at the Gregory School, 1926 (Houston, Texas)

The LEED Gold African American Library at the Gregory School is housed within a historic 1926 building. The brick structure was the second home of the first public school for Black students in Houston, started in 1870 in a wooden building. Designated as a State Archaeological Landmark, the Gregory School is located in a historic district known as Freedmen’s Town, possibly the city’s oldest African American community.

The library serves as a resource to “preserve, promote, and celebrate the rich history and culture of African Americans in Houston, the surrounding region, and the African Diaspora," with historical exhibits, a digitizing lab for old photographs, oral histories from Houston residents, and collections for researchers and the local community.

The project team was able to keep the carbon footprint small on this brownfield site. Under the LEED for Building Design and Construction rating system, the library project achieved eight out of 14 Sustainable Sites credits. The area of the original 26,000-square-foot building was kept the same to minimize site disruption, and a reflective “cool roof” was installed; non-roof surfaces were also paved with highly reflective material.

Ten out of 15 Indoor Environmental Quality credits were achieved through a strong focus on strategies to create a positive experience for library patrons and a healthy indoor atmosphere. Low-E window glazing improved the thermal efficiency of the building while also providing views to the outside from 91 percent of the regularly occupied spaces in the library. Low-VOC coatings and wood products were used to protect staff and visitors from off-gassing, and the floor does not require waxing, further reducing chemical exposure.