We built this city… from waste

¡°Eventually, the future city would make no distinction between waste and supply (¡­)¡± - Mitchell Joachim

Having lived in Africa for a year opened my eyes to many aspects of life. I have never experienced a place where the saying ¡°One man¡¯s waste in another man¡¯s treasure¡± was more accurate. The items I was throwing away without thinking twice, soon found new owners and were cherished as novel. At some point I realized that a few of my neighbors were walking in shoes once mine, which had been resized and remodeled to fit their needs. Several boxes or packages, which had been an impediment to me, were cleaned and turned into lunch boxes for the local kids. This imagination and creative thinking of how to reuse, resize or even give a new function to earlier discarded products was a trigger to look at waste as a resource rather than a problem. The fact that this happens on a rather small scale in comparison to the tons of waste transported daily to the opened landfill, only proved the necessity of an alternative approach.

Aware of the city context and its situation, I then realized that waste could be a key material in construction, as it is a seemingly renewable resource within the limits of any metropolis. Addis Ababa, the capital of Ethiopia, is one of the fastest growing municipalities on the planet. With an urbanization rate of around 4 percent, the city might be a home to 12 million inhabitants in 2050 (a considerable increase from today¡¯s 5 million). As a consequence, the already existing housing shortage will only worsen in the city¡¯s struggle to catch up with the demand. In addition, Ethiopia, like the majority of African countries, depends on the most common materials such as cement and steel, which mostly need to be imported from India and China. Highly taxed, these supplies only deepen the financial struggle and slow down construction sites in the country, closing a viscous circle.

One of the most obvious steps when looking for alternatives is the search for locally available and easily accessed resources that could substitute expensive and imported ones. One such abundant waste material in Ethiopia is straw, a by-product of agricultural food production, which is mostly burned on the fields. In April 2012, a research project was launch to investigate if straw could, in fact, be a structural building material of the future. The ETH Zurich in collaboration with the Ethiopian Institute of Architecture, Building Construction and City Development and the Bauhaus University in Germany built a prototype of double story living unit in Addis Ababa, Ethiopia. Pressed to modular panels, straw proved to be a load-bearing alternative to wood, especially important in a country where deforestation developed into a major problem in recent years. So far, straw is seen as a valueless substance, on the other hand it is widely available and ready to be used for the construction industry. All it needs is the infusion of knowledge on how to do so.

This research is not limited to developing countries. Quite the contrary; it pursues solutions that would suit various urbanized regions. However, when I moved to Singapore, I realized that the challenge in developed areas is yet another: the stigma of refuse, which hinders its full implementation in the urban construction process. To start with the less academic argument, Singapore is known for its peculiar rules and regulations including horrendously high fines for littering or, to be frank, for any kind of social disturbance. Refuse is treated with an ¡°Out of sight - out of mind¡± attitude.

Singapore strives to find the most advanced, high-tech solutions for everything, including waste management, which is already considered as one of the most advanced in the world. An example would be Semakau Island - an artificially created island out of incinerated waste ash. Out of sight, ships carry the remains of Singapore¡¯s incinerated waste away every night into the sea to create a new, green tourist attraction for the future. However, there might be an alternative solution to burning waste, which is a rather ineffective treatment considering the monetary value of today¡¯s trash. Seen as a resource rather than as a problem, this waste could be the starting substance for new, innovative building materials, which this ever-growing city is in dire need of to sustain its construction.

The doctorial seminar, ¡°Constructing Waste¡¯, which I conducted in Fall 2012, was a first approach to this search on an academic scale at FCL. But implementing refuse for future buildings will require a different mindset. One possible idea could be to change our linear understanding of products being destined for landfills or incineration plants at the end of their time. As such, the seminar focused on the remodeling of everyday consumables in order to pre-design them for a second life cycle as a building material.

The first opportunity to apply these efforts in full scale presented itself soon after. ETH-Zurich will be exhibited during ¡®IDEAS CITY¡¯ 2015, in New York, an event curated by the New Museum. Responsible for the pavilion design, my team proposed an architectural solution, which puts emphasize on questions of resilience and sustainability. The resulting proposal ¡°Airless¡± utilizes discarded PET bottles as a stiffening element in a ¡°vacuumized¡± building structure. The bottles, which can be found in any trash bin in New York, are packed in prefabricated arch-shaped foil tubes. Once filled, the air in these tubes is sucked out to create a lightweight, super inexpensive and very efficient self-sustainable structure, which can be used to construct large span spatial arrangements. Additionally, the process does not alter any of the bottles, so at the end of the exhibition they can then be reintroduced into the existing recycling system. Through such activities, we hope to show that ETH Zurich is on the forefront of future-oriented thinking and research when it comes to using waste as a construction material.