In April 2020, the US Embassy in London received a Leadership in Energy and Environmental Design (LEED) Platinum certification from the United States Green Building Council. LEED is the most widely used green building rating system in the world and the Platinum designation is the highest possible rating a building can receive.

The new embassy, completed in 2017, was designed with a holistic sense of responsibility to the environment. The site itself was a 4.9-acre brownfield along the south bank of the river Thames, helping to invigorate the surrounding district with new housing and commercial projects, transportation infrastructure, and public amenities including a linear park extending from Vauxhall to Battersea. The landscape surrounding the embassy includes a pond and pedestrian walkways that not only offer a restored ecosystem and enhanced biodiversity of grasses, wildflowers, and birdlife, but also a carefully integrated stormwater strategy. 

The building's lean cubic form helps save energy and cost. Its highly insulated envelope—comprised of an inner envelope of laminated glazing and an outer envelope of ethylene tetrafluoroethylene (ETFE)—minimizes solar gain and glare, reducing demand for cooling and ultimately decreasing the size of mechanical systems and energy use. Efficient air flow, passive chilled beams, and chilled ceilings minimize energy use and create a comfortable work environment. The design also reduces peak energy demand and employs alternative energy sources like photovoltaics and ground source heat pumps to reduce overall energy consumption.

Open workspaces inside the embassy prioritize natural daylighting and views, and interiors make use of the healthiest available materials. Building systems allow individuals to control their environmental comfort, including temperature and lighting. Six gardens within the building bring the natural world indoors, improving air quality and encouraging occupants to move about and interact in an atmosphere that fosters well-being.  
 
“At the outset of the London Embassy project, ambitious goals were set for environmental performance," said Richard Maimon, partner at KieranTimberlake. "Stringent security requirements made impossible the many passive strategies upon which high-performance buildings rely, effectively starting the design process with an energy deficit. Dozens of alternative strategies were developed to advance the design beyond this deficit, ultimately allowing it to reach the highest levels of performance. Collaborative and holistic design work across the entire team–client, contractor, engineers, consultants, and architect–were essential to this achievement.”