Bloomberg’s European headquarters, designed by Foster + Partners, has won the Stirling Prize, the UK’s most prestigious architecture award. Located in the heart of the City of London, the Bloomberg HQ comprises two buildings connected by a bridge and was designed with sustainability in mind. It is the top-rated major office building in the world based on BREEAM, the most established sustainability assessment method. The sandstone facade is defined by large bronze fins that vary in scale, pitch and density according to orientation and solar exposure, while providing shade and ventilation. At the center of the 3.2-acre site is a public pedestrian arcade that re-establishes an ancient Roman road and a museum displaying the Roman temple of Mithras in its original location, where it was discovered 60 years ago. The flow through the building is choreographed by art: Upon arrival, visitors enter a double-height artwork made with curved timber shells called “Vortex,” while the public plazas in the outdoor arcade are highlighted by a three-part water sculpture by Cristina Iglesias titled “Forgotten Streams,” which pays tribute to an ancient river that once occupied the area. The Stirling Prize is awarded annually by the Royal Institute of British Architects (RIBA), which honored the Bloomberg building over five other finalists. “After vigorous debate, the jury reached a unanimous decision – Bloomberg’s new European HQ is a monumental achievement,” RIBA President Ben Derbyshire said in a statement. “This building is a profound expression of confidence in British architecture – and perfectly illustrates why the UK is the profession’s global capital. This role and reputation must be maintained, despite the political uncertainty of Brexit.” Bloomberg say the building uses 73% less water and 35% less energy compared to a typical office building, due to innovations applied to power, lighting, water and ventilation systems. The internal airflow is adjusted by smart sensors based on the number of people occupying each area of the building at any given time, reducing CO2 emissions by approximately 300 metric tonnes each year. A further reduction of 500 to 750 tonnes is provided by a combined heat and power generation unit that reuses its own waste heat for cooling and heating the building. “From our first discussions to the final details of the project, Mike Bloomberg and I had a ‘meeting of minds’ on every aspect of the project – its sustainable focus, commitment to innovation and drive to create the best workplace for Bloomberg employees. The RIBA Stirling Prize is a testament to the incredible collaborative spirit that has underpinned the entire project from start to finish,” said Lord Norman Foster, founder of Foster + Partners, in a statement. The heart of the building is the 6th floor “Pantry,” a large concourse and café space that offers panoramic views of the city. A distinctive bronze ramp winds down to the office floors below, and is designed to stimulate chance meetings and impromptu conversations. The hi-tech workspaces have ceilings fitted with 2.5 million aluminum petals that regulate acoustics, temperature and light. “When we embarked on this project, we wanted to create a cutting-edge design that would push the boundaries of what an office building could be, which meant setting new standards for openness and sustainability. At the same time, we wanted to honor London’s history and contribute to its vitality,” said Michael R. Bloomberg, the American businessman and former New York City mayor, in a statement. “We knew that if we could achieve both objectives, we’d have a building that would inspire everyone who set foot inside it.” The RIBA Stirling Prize, now in its 23nd year, is awarded to the architect of the most significant building of the year in the UK based on such criteria as design vision, innovation, originality, accessibility, sustainability and the capacity to stimulate and delight occupants and visitors. The Bloomberg HQ was shortlisted in July along with five other buildings, including the New Tate St. Ives gallery in Cornwall and the Bushey Cemetery in Hertfordshire. Last year, the prize went to the Hastings Pier, which was destroyed in a fire in 2010 and redesigned by London-based architecture firm dRMM.