Above the street level in any city floats an untapped resource. This airspace—the void above the road and between buildings—is, for several practical reasons, unused. Surprisingly, a science-backed design proposal suggests that this empty void doesn’t have to just sit empty. Instead, the air above the street could be turned into an entirely new kind of building plane.
Named Oversky, the project proposes a series of semifloating structures that could fill in this unused aerial space. Based on the same technology that allows zeppelins to float, these modular structures would combine into an occupiable cluster of rooms in the sky, connected to adjacent buildings or other fixed structures to enable access. Developed by research and design studio Framlab, the project is an attempt to show how the urban void dozens of feet above the street can be reimagined. “The formed ‘cloudscape’ serves as a new kind of public space,” Framlab’s Andreas Tjeldflaat writes in an email.
Tjeldflaat describes it as a speculative infrastructural system based on proven technologies, including the use of enclosed carbon fiber cells of lighter-than-air and inert helium, enabling the modules to maintain a rigid structure and hover like tiny inflammable airships. Combined into Tetris-like amalgamations, these floating modules could act like individual rooms, offices, or storefronts in the sky.
“Suspended walkways allow the clusters to connect to adjacent building facades,” Tjeldflaat explains.
But this concept isn’t just an architectural pie in the sky. It could also be a new tool in the urban fight against climate change. One pervasive issue facing cities around the world is what’s known as the urban heat island effect. Dense buildings and paved streets absorb and retain more heat than undeveloped or natural land, making cities hotter and leading to the increased use of air conditioners and the emissions they produce.
The modules proposed by Oversky would create shaded microclimates that reflect sunlight and radiation, bouncing back into the sky what would otherwise get absorbed into the dense surface of the built environment. Through what Tjeldflaat calls nanophotonic engineering, the modules would feature “a foam-like material structure with nanoscale air pockets” capable of radiating heat back out of the atmosphere while also cooling the shaded space below. Trees, of course, provide this type of shade quite effectively, but Oversky aims to be an even bigger and more efficient canopy. Tjeldflaat’s initial renderings of the concept show it covering just a portion of the space between buildings, so as to not completely shut out the sun to pedestrians and urban dwellers below.
Recently on display in an exhibition on architecture and climate change at Sweden’s Bildmuseet art museum, the project suggests an audacious alternative to our current highly polluting forms of urban air-conditioning. A conventional air conditioner discharges a significant amount of heat as well as polluting hydrofluorocarbon compounds, “exacerbating the very issue it seeks to mitigate,” Tjeldflaat says.
He notes that much of the air-conditioning used in cities relies on fossil fuel energy—a problem that is expected to only get worse. “The global demand for cooling is estimated to require a threefold increase in energy use by 2050,” Tjeldflaat says.
Oversky is one highly theoretical solution. But Tjeldflaat argues that even if these floating modules aren’t coming to an urban aerial void any time soon, the materials and concepts behind the idea could be implemented in more down-to-earth projects today: “The panels of the modules can certainly be employed on their own as part of more conventional building and infrastructure projects.”