US Embassy in London

The US State Department envisioned a new embassy in London that would serve as the centerpiece of one of America's longest-standing and most valued relationships. It also aspired to set a new paradigm in embassy design by representing the ideals of the American government—giving priority to transparency, openness, and equality, and drawing on the best of American architecture, engineering, technology, art, and culture. Our challenge for the Embassy was to encompass these values, creating a strong sense of welcome while also meeting specific functional requirements for security, diplomatic work, and environmental sustainability. The Nine Elms district, a South Bank industrial zone under intense redevelopment, is a unique setting for the new Embassy. With an estimated 1,000 daily visitors and 800 staff, the Embassy is poised to establish a strong framework for the urbanization of Nine Elms. A civic plaza and park contribute to this revitalization by connecting the Thames embankment and Nine Elms Lane to a new pedestrian greenway extending from Vauxhall Station to Battersea. The Embassy stands at the center of this burgeoning area of London, with a public park containing a pond, walkways, seating, and landscape along its edges. Curving walkways continue into the interior of the building with gardens on each floor that extend the spiraling movement upward. The internal gardens evoke American landscapes, enhancing circulation by providing alternative paths through the building and informal meeting and gathering spaces. The form of the Embassy is a transparent crystalline cube set atop a monumental colonnade—a radiant beacon at the heart of Nine Elms. Its high-performance facade is made of laminated glazing and an outer envelope of ethylene tetrafluoroethylene (ETFE), a transparent film shaped to minimize solar gain and glare, affording generous natural light throughout the interior and access to the site’s striking views. The tonality of the envelope shifts with the weather and time of day. With sustainable initiatives including brownfield redevelopment, natural habitat creation, healthy and responsibly sourced building materials, and energy efficient equipment, the Embassy is on track to receive LEED Platinum, BREEAM Outstanding, and EPC-A+ ratings and is on track to achieve net carbon neutrality as defined by BREEAM, pending construction phase review. The Embassy takes a two-fold approach to sustainability. First, the building’s energy efficient design conserves as much energy and water as possible through strategies such as daylight-responsive lighting and shade controls, passive and active chilled beams, grey water recycling, and efficient mechanical systems. The landscaped pond is part of an integrated water system that aims to retain all rainwater that falls on the site for landscape irrigation and to keep pollution out of local waterways. Second, the Embassy harnesses renewable resources including solar energy gathered by photovoltaic cells and geothermal energy generated through ground source heat pumps, which use the consistent temperature of the earth to heat and cool the building. The Embassy maximizes efficiency by simultaneously creating heat and electricity by way of combined heat and power (CHP) units. This system generates enough energy to satisfy the Embassy’s power and heating needs while also creating an excess that can be exported to the local community. The design for the new Embassy represents a holistic fusion of urbanism, building, and landscape. It is both evocative and performative, helping to define a new environment for diplomacy while mapping a passage toward a diplomacy for the environment.