More than 56% of the world’s population currently lives in cities, according to The World Bank, with this trend expected to continue. In fact, The World Bank estimates that by 2025, almost 7 out of every 10 people will live in cities. In South Africa, this percentage is even higher, with 68% of the country’s population currently living in urban areas. As urbanisation has increased, however, so has urban sprawl and pressure on infrastructure. Philip du Toit, Project Architect at BPAS Architects, suggests that we need to look at our cities with a fresh lens to find sustainable ways of addressing increased urbanisation.

Palimpsest – Layering (sub)urban fabric

Du Toit proposes a concept he calls “Palimpsest  – layering (sub)urban fabric”. The term palimpsest was originally used to describe an ancient form of recycling, where parchment (which was expensive and difficult to come by) would be repurposed, scrubbing some or all of the existing text off of it to reuse it. Often, traces of the original content remained. This term has since been borrowed for other situations, such as artists reusing canvases and creating layered artworks.

Du Toit first became aware of the idea of palimpsest in art through the photography of Jason Shulman, who creates artworks by photographing  whole films into single, abstract composite images. He began to implement the idea in his own photography, but using multiple photos of buildings and scenes in the real world.

As he was studying architecture, he began to consider how the idea of palimpsest could apply to urban design. “I ended up doing my thesis at the University of Pretoria on this idea, looking at how we can use existing buildings and build on them in a three-dimensional environment to create new spaces,” he explains.

Rather than developing empty sites or demolishing old buildings to make way for new ones, Du Toit suggests reusing the canvas of the cities to improve densification, minimise development costs, address housing pressures in urban and suburban areas and combat urban sprawl. This methodology also allows for wasted space to be repurposed, and for individuals – not only large-scale developers – to create solutions for themselves.

Green solution

“It’s a green solution to use existing buildings,” says Du Toit. “It can help to address various issues, such as reusing buildings in cities that have become abandoned, or addressing changing population needs. There are examples of how this has worked internationally, and I think it’s something that could be very effective in South Africa too.”

Du Toit cites examples of how this methodology has worked well, and others where it could be improved upon. For example, in California, Jonathan Segal pioneered a model of architects as developers. To help address a shortage of rental housing in San Diego, he designed, built, and managed 15 projects that are credited with playing a key role in the city’s renaissance.

On the other end of the spectrum, Torre David, an incomplete development in Caracas, Venezuela, that was halted midway is an example of organic urban palimpsest. A community of homeless people moved into the development and repurposed the space for their own needs.

While these type of “urban slum” applications are not ideal, Du Toit says that when properly managed, urban or suburban palimpsest can be undertaken in a way that ensures existing infrastructure and property prices are positively affected, rather than compromised.

Vertical urban interventions

For example, it’s increasingly common in South Africa for homeowners in suburban environments to build a granny flat in the backyard to accommodate ageing parents or grown-up children. Instead, Du Toit suggests exploring vertical urban interventions, which, if applied correctly and on well-suited properties, could help make cities greener.

“Homeowners working with architects can ensure that these interventions could take place based on good urban design principles,” he says. “The redevelopment, or layering, of existing single residential properties could be used to help provide more houses, offering opportunities for more people to live closer to commercial, social and educational nodes. They also offer additional income for homeowners by way of rental.”

He says that the City of Cape Town has created a precedent for this by changing its town-planning regulations in recent years to allow for up to three dwellings per residential erf, which simplifies redevelopment procedures by negating a zoning change application.

There is also room for developers to get involved in bigger projects, particularly within urban nodes, by partnering with city councils and town-planners to relook existing properties with an eye for development. “This type of partnership means there’s proper consideration given to green infrastructure, such as rainwater harvesting and solar installations, which ensures existing infrastructure is not put under strain,” he says. Urban and suburban palimpsest can help cities to evolve in the wake of COVID-19 and hybrid working, which has seen a downturn in the need for office space, as well as curbing urban sprawl, creating new economic opportunities and catering for shifting community dynamics.

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