Twenty-Five Year Award: Broadgate Exchange House

Located in London’s Broadgate Development, the ten-story office building designed and engineered by Chicago-based Skidmore, Owings & Merrill spans over the tracks of London’s Liverpool Street Station. The jury recognized the hybrid building and bridge site for its holistic approach encompassing architecture, engineering, and master planning.

The AIA announced today that The Broadgate Exchange House, designed and engineered by Skidmore, Owings & Merrill (SOM), has won the 25-Year Award, celebrated for its function to holistically achieve urban planning in an already dense city and structural design that serves both form and function. The 10-story office building, which opened in 1990, employs mid-century Modernist, cube forms with curved arches that support the building over rail infrastructure. Positioned as the centerpiece of the Broadgate Development—which is also master planned by SOM with the help of British Rail—the designers chose one of the last remaining areas available for development, in an area characterized by thousand year-old roads and more recent rail infrastructure, as a result of London experiencing a financial boom in the 1980s, demanding a need for more office buildings.

Credit: SOM | © Alan Delancey for Wordsearch

Acting as both a building and bridge, the hybrid structure enables the Liverpool Street Station to retain use of its 18 rail tracks underneath the office building. Framed by four parallel arches, each set placed internally and externally, the building relies on these curved structures, so that it does not rely on columns. The four arches spring out of eight piers, that the Exchange House sits on, four on each side, each 260 feet across. The arches are tied to the bottom seven stories, providing structural support, and allowing the bridge to act as a building.

Jury comments:

“The structural and urban concepts integrated within the project were expressed with an inevitable clarity and pragmatic elegance that even after twenty-five years, continues to highlight the entire urban setting that it helped generate.”

“The project embraced the technical challenge of having the building actually bridge the broad expanse of tracks below by developing a unique and efficient tied arch structural system, which also suspended an open entry plaza and pubic courtyard at the building’s first floor, profoundly enhancing the urban condition.”

The 25-Year Award is given to architects who designed projects that have been built for 25 for 35 years and consistently maintained their architectural design and significance. To be eligible, the design must be commissioned by an architect who was licensed in the United States when the project was completed.

This year's jury for the 25-Year Award included Calvin Lewis, FAIA, professor of Iowa State University's Department of Architecture (chair); Ray Calabro, FAIA, a principal with Bohlin Cywinski Jackson; Nicole Gerou, Assoc. AIA, Midwest quadrant director of the AIAS, representing Lawrence Technological University; Ana Guerra, Assoc. AIA, of Jacobs, winner of an AIA Associates Award in 2014; Sherri Gutierrez, AIA, vice president and office director of Arquitectonica in Miami; Jill Lerner, FAIA, principal with Kohn Pedersen Fox (KPF); James McDonald, AIA, principal with A&E Architects; Waller McGuire, executive director of the St. Louis Public Library; and Angela O'Byrne, FAIA, president of Perez in New Orleans.