A new high-tech US embassy building was recently completed in London. The billion dollar project has been in the works for seven years and takes the form of a massive glazed cube supported atop colonnades. It's more efficient than you may expect too: the building features rainwater recycling and solar panels, and is slated for both the LEED Platinum and BREEM Outstanding green building certifications.

Designed by Kieran Timberlake, the US Embassy in London measures 518,050 sq ft (48,128 sq m) and is 65 m (213 ft) tall, or 12 stories. Its glazed facade is partly covered in a transparent film of plastic (ethylene tetrafluoroethylene to be exact) that's shaped to reduce solar heat gain and glare, while maintaining the Thames view and allowing natural light inside.

The transparent design is also meant to represent transparency and openness in US politics.

"The State Department envisioned a new embassy that would serve as the centerpiece of one of America's longest-standing and most valued relationships," explains Kieran Timberlake. "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."

There are three entrances to the embassy. A consular entry receives visitors seeking passports and visas, the main entry is for staff and visiting dignitaries, while the smallest is a service entry.

Once inside, there are multiple indoor gardens meant to evoke America's landscapes and the office layouts themselves are flexible. Lots of contemporary artwork by both British and American artists is on display, to celebrate the shared culture on both sides of the Atlantic.

Sustainable tech in the embassy is pretty extensive and includes daylight-responsive lighting and shade controls, efficient demand-controlled ventilation, roof-based solar panels and ground source heat pumps, which use the earth's consistent temperature to help heat and cool the building more efficiently.

A rainwater recycling system captures water for use in toilets, irrigation in the embassy's interior gardens, and the pond. The water fixtures are efficient and effort has been made to make the area an ecologically valuable landscape for wildlife.

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