Can a building contribute to reducing carbon dioxide in the atmosphere throughout its life? Can cities and architecture play a decisive role in carbon sequestration? Based on data and a concept developed by Skidmore, Owings & Merrill (SOM), the answer that emerged from COP27 in Sharm el-Sheikh was yes. Dubbed Urban Sequoia NOW and the result of extensive research conducted by the studio, the concept represents a radical rethink of architecture and construction practices that can be implemented right away. The initial figures from the research were actually presented at COP26, but now, thanks to the work of an international and interdisciplinary team, they’ve been translated into a practical approach that can be used for different scales and types of architecture. In other words, this visionary idea has now taken its first steps to being a buildable reality.
Using the system, a high-rise would reduce upfront embodied carbon by around 70% when compared to the construction of a normal high-rise. And this percentage continues to rise throughout the building’s life. Five years after construction, the reduction in whole-life carbon would reach 100%. Then, over a hundred years, an Urban Sequoia building will absorb more than 300% of the amount of carbon emitted during construction and operation.
“We recognize the need to alter the trajectory of climate change by going beyond net zero,” explained Chris Cooper, partner at SOM, during the presentation at COP27. “We need to take carbon out of the atmosphere through the built environment, and we have developed a design to do just that.”
To achieve this goal, the SOM team treated buildings like living organisms whose “breath” reduces embodied carbon (i.e. the carbon dioxide linked to materials and construction throughout the life cycle of a building), thereby generating energy and absorbing carbon from the atmosphere, while also achieving a longer life expectancy than today’s typical 60 years.
As mentioned by Yasemin Kologlu, SOM design principal, accomplishing these goals is to totally rethink the design, construction, materials, mechanical systems, and integrated technologies of buildings.
Instead of following a typical additive construction approach, in which building systems, along with carbon in the atmosphere, are added to the built structure, Urban Sequoia NOW offers a subtractive process that integrates more systems into one.
The heart of the approach is a ventilation and air (and carbon) recirculation system based around openings directed towards the core of the building. The carbon captured by this system is then stored for use in various industrial applications, completing the carbon cycle and forming the underpinnings of a new circular carbon-removal economy.
Another fundamental element of the concept is garden areas in the body of the building. And then there are the materials, including wood and bio-concrete, to reduce embodied carbon emissions, and solar glass.
Although the concept can adapt to the most varied settings and building types, it was developed in particular for the most densely populated areas of the earth and, as a result, those most affected by carbon emissions.
“Urban Sequoia is a systems approach, a philosophy,” said SOM sustainability director Mina Hasman. “It is a way of thinking about cities as ecologies, as living and breathing systems that can be reconfigured to achieve dramatic reductions in whole life carbon, reframing the built environment as a solution for the climate crisis.”
Architects: Skidmore, Owings & Merrill (SOM)
Render courtesy of SOM