Everyone who has ever built anything—a model, a birdhouse, or small pieces of furniture—has a clear sense of the amount of things that can go wrong during the construction process. A screw that is impossible to tighten fully, a warped wooden board, an inattention or a miscalculation that can frustrate plans instantly. When we transport these small inconveniences to a building scale, with countless processes and many different people involved, we know how complex a work can become and how many things can get out of control, taking more and more time and requiring more and more resources to finish. And when we talk about a building that needs to float, be completely self-sufficient, and, after fulfilling its useful life, be completely reused—could you imagine the technical challenges of building something like this?
Buildings have always been used to represent values. From the Gothic cathedrals of the Catholic Church to mirrored bank buildings, architecture can generate an atmosphere of power, confidence, grandeur, and more. For the design of the headquarters of the Global Center on Adaptation (GCA) offices, a global knowledge center that supports countries, organizations, and companies with knowledge and consultancy in the area of climate change, the architecture must reflect concepts of resilience and sustainability. Fun and functional, the floating structure constitutes a key element in a recently remodeled port environment, providing public space at the water's edge—and even a swimming pool. In addition to the offices, the building also has public spaces, most notably a restaurant with a large outdoor terrace.
This idea of developing a floating building that could adapt to changes in sea level is, above all, a highly symbolic gesture. The Floating Office Rotterdam (FOR), designed by Powerhouse Company, is self-sufficient, generating solar energy and relying on a water-based heat exchange system. In addition, its structure is entirely made of engineered wood, which not only dramatically reduces its carbon footprint, but also allows it to be completely reusable, as the structure is assembled without adhesives and therefore easily disassembled. The 970 tons of wood were also taken from German forests close to the construction site, and store as much CO2 as is burnt in an 8 million km journey by an average car.
We spoke to architect Albert Takashi Richters, who worked on the project, and he pointed out some of the issues that the project posed. According to him, “The main challenge of building a floating structure in the first place is obviously that it floats. This means that the floating base must be stiffened using tensioned cables. Other than that, it essentially comes down to balance and uniform weight distribution at the top: any imbalance will have to be compensated with ballast and this dead weight is something to avoid, as it immediately affects the dimensions. These challenges basically force the designer to think effectively about the different components that the building consists of and, in our case, resulted in a very elemental approach to the project. The first way to achieve uniform distribution and balance is to have a clear grid. Balance means that the laws of nature determine a preference for symmetry. We always felt that symmetry in long and short elevations would give the project a strong presence, but in a building like this, it also makes structural sense.”
While there are several structural challenges, there are possibilities opened by the chosen building system: “An advantage of displacing a sufficient volume for the building to float is that it means that there will be a lot of space under the building to place the building plant for climate control and energy storage. This meant that the roof could be kept free for vegetation, as well as a wide range of integrated photovoltaic panels to power the entire building. Contact with water means that the cooling benefits can be enjoyed much more directly through a heat exchange system integrated within the floating base. This is particularly useful for office buildings where the overall heat load is greater than the cooling load.”
Such an elegant structure of glued laminated wood and CLT stands out in the landscape. As is usually done in structures of the type, the structure was totally manufactured and drilled in a factory before it was transported to the site, where it was assembled quickly with the help of cranes. Richters points out that “When it comes to working with wooden structures, the main challenge is that the different parts of the building must be put together in a different order. In the future, the building may have to pass through the Rijnhavenbrug, for example, which means that the dimensions must be compact regarding the building's width and height. To keep the floor heights compact, we chose to integrate the climatic systems within the structure: this means that earlier in the process, the ducting systems already had to be chosen—conventional ducts would not fit in the beams without decreasing their structural integrity, but thicker beams were not an option due to space and weight restrictions. Therefore, a system had to be planned where ducts are divided into smaller tubes. In processes like this, the architect and structural and installation consultants need to work together from the get-go.”
