Sustainability Case Study: Cairo's Green Roofs

When we think of traditional roof tops we may picture them as brute, mechanical, heated and noisy due to the use of machinery, with a concrete stairwell and an overall still enclosure. In an almost immediate sense, the physical nature of green roofs gives us a sense of relief, in mere thought about the concept of greening rooftops. We almost become poetic while imagining the possibilities that can arise from vegetating such a mechanical component of a building beaming with life and livelihoods. We can reflect on one of the most essential names in modernist architecture, Le Corbusier , and his five points of architecture, where the Swiss-French architect, along with Pierre Jeannert, wrote the manifesto on supports, free design of the ground plane, horizontal windows, free design of the facade and roof gardens. Le Corbusier's Villa Savoye in Poissy, France sums up his five points of architecture, like a manifesto in itself, but while the opportunities that a residence benefits from the design of a roof garden and the expansion of spatial use beyond physical confines, roof gardens on a wider urban context play a far greater part in addressing serious environmental problems and even a response to over-consumption of resources, excessive use of energy and pollution.

Cairo is Egypt's largest metropolis, with 11 million inhabitants calling it home, and a growing population with challenging urban, social, economic and environmental challenges. Urban gardening and vegetating roofs becomes part of the responsive strategy to address serious environmental challenges, mitigating urban heat island effect, improving energy efficiency in buildings, reducing storm water runoff and increasing biodiversity. In 2019, Egypt’s Ministry of Environment launched a nationwide green-roof initiative to advocate and support the implementation of planting building and facility roofs, reducing as such pollution levels in the country and providing an eco-friendly use of space. Cairo has introduced this initiative to plant gardens on the rooftops of Cairo’s buildings, as part of the sustainable development plan, which aims at mitigating air quality problems as well as assisting with the reduction of excessive electricity supply and demand. Promoting the concept of urban agriculture in the expanding city of Cairo is local business and movement Urban Greens. Their objective is to advocate for a 'new food movement encourages pesticide-free, clean and fresh and local produce.' The strategy of Urban Greens feeds into the dynamic of rooftop farming in Cairo and re-purposes rooftop spaces within dense urban nodes in the city.

Smart cities begin with smart and sustainable urban strategies that analyse the challenges of existing urban and infrastructural anomalies, proposes mitigation methodologies and responses with an initiative. Imagining an urbanism that involves aquaponics, hydroponics and greenhouses on Cairo's rooftops, is in essence a transformation from the status quo, i.e. the existing dense and overpopulated Cairo. The concept of 'ecological urbanism' requires a ‘new sensibility’- one that has the capacity to successfully integrate the various contradictory elements of both the ecology and the urban environment. Density is another challenge added to the concept that is ecological urbanism. To Mohsen Mostafavi, understanding the rises and falls of a city’s population, allows us to control and plan the shape of the urban environment in relation to the level of its inhabitants and their interactions with the urban context. We can view sustainable projects like these as 'urban activism'; beyond the aesthetics of greening concrete jungles, Urban Greens strongly believe in the broader effects of advocating for urban agriculture that is just, provides food security within struggling social contexts and brings low-income inhabitants of Cairo a form of support. Urban Greens are effectively bringing resilience to a city that faces several challenges, most significantly environmental, but how it addresses those challenges is by diversifying resource-dependence and ultimately positively changing lifestyles and habits of spatial use.