The people of Rotterdam know a thing or two about living on the water. About 90% of the second-largest city in the Netherlands lies below sea level, which leaves it vulnerable to rising waters. To prepare for the inevitable, the waterlogged city has been building parking garages that can double as emergency reservoirs, parks that can act as retention ponds, and homes that sit on floating pontoons.
Now, Rotterdam has added another tool in its climate change tool kit. The city recently unveiled the world’s largest floating office. Moored at Rijnhaven port, the structure was designed to rise and fall with the tide, so even when the water rises enough to flood the harbor, the building will rise with it and be spared any damage.
The Netherlands has been building floating homes since the mid-1980s. In 2019, it even welcomed the world’s first floating farm, which spans about half an acre and is now home to 40 cows. This floating office marks yet another step in the country’s endeavor to coexist with water. It also provides a framework for coastal cities in the U.S. that are threatened by sea-level rise, like New York City, New Orleans, and Miami.
The Floating Office Rotterdam was designed by local architecture firm Powerhouse Company, which is also redeveloping a 12-acre site along the harbor. The three-story building spans 50,000 square feet and sits on a floating foundation that’s about 60 feet away from the mainland and is accessible via a floating gangway.
The building houses the Global Center on Adaptation headquarters—an international organization founded in 2018 to support and advise countries and companies on climate change—plus a restaurant and public terrace with a swimming pool. The architects have an office there, too.
The whole structure consists of two parts: a floating concrete foundation and a timber building. To build the foundation, the architects took a page from floating homes, which are built on a floating concrete block. Here, they combined 15 floating blocks to form the base of the office building, then assembled the building using elements that were fabricated elsewhere, “like Lego construction,” explains Nanne de Ru, the firm’s founding partner. The entire structure was then fastened on a pair of large mooring poles that help stabilize it and prevent it from swaying. “Even when it’s stormy, it feels level,” he says.
The building may be the world’s largest floating office, but its location on the water helps make it more sustainable, too. “The floating concrete foundation acts like a large heat and cooling reservoir,” de Ru says. The team also used the water in the harbor to cool the building.
The building operates off-grid and produces 140% more energy than it uses. This is helped by more than 9,000 square feet of solar panels on the roof, overhanging balconies that provide shade, and thick woolen insulation in the walls. From design to completion, the structure took about 18 months to build, compared to the roughly two to three years it takes to construct a building on land. De Ru says it was about 30% more expensive than a similar building would have been on land, but that those costs will be offset over time by lower energy use.
The concrete foundation was designed to last about 50 years, which is about the average life span of a regular house. At that point, the wooden structure could move to another location. “You could unscrew the entire building and rebuild on land,” de Ru says, adding that alternatively, “you can always unmoor it and position it in another location.” (The fact that the building essentially sits on a barge also helped secure a permit more quickly.)
Floating structures have long been a dream of utopias, from Buckminster Fuller’s unrealized proposal for a floating city in Tokyo Bay in the 1960s to Danish starchitect Bjarke Ingels Group’s recent proposal for a floating city that can house more than 10,000 people. At a smaller scale, though, the concept has been inching toward reality: from a floating public space on a London canal to a floating school in Makoko, Nigeria.
In Rotterdam, the floating office building draws a lot from the country’s acquired knowledge of living on, and with, the water. But de Ru believes the concept could work anywhere. “You might be able to build such a structure in Manhattan, for instance,” he says. “There is a lot of Dutch knowledge in this project, but it’s an easy and simple building that can be built anywhere in the Western world.”