In 2010 the South African Government initiated the ‘In-Situ Upgrading of Informal Settlements’ scheme. One of the primary goals of this project is to upgrade 400 000 informal housing units (known as ‘shacks’) by 2014. This housing target coincides with the City of Cape Town’s 2014 Energy and Climate Change Strategy goals – meaning if both the 2014 informal housing and energy targets are to be achieved, it is imperative that the housing upgrades are environmentally, economically and socially sustainable.
The study established what the major housing issues faced by residents of Khayelitsha (Cape Town’s largest informal settlement) were, and based on these findings four key strategies of upgrading informal shelters were defined – namely: elevating, insulating, ventilating and shading the structure. To achieve these strategies, specific incremental improvements were selected based on a literature search that reviewed both local and international transitional housing designs, as well as interviews with South African housing NGO’s, engineers and architects.
These options were evaluated and prioritized using Multi Criteria Decision Analyses. In keeping with the sustainability aspect of the study, the analyses considered the financial implications, thermal comfort improvements, potential for skills-training and sustainable usage of materials of each option.
The results of these analyses were used to make recommendations to the Human Settlements Department detailing the type of in-situ housing upgrades that would most effectively improve the shelter conditions in Khayelitsha. This incremental upgrading approach was determined to be more cost-effective and less material-intensive than the more common ‘eviction, destruction and rebuilding’ slum-upgrading strategy. Furthermore, the cumulative benefits of the upgrade options were modeled on IES-VE and results indicated up to a 7oC temperature reduction during peak summer periods and much more moderate daily temperature fluctuations compared to baseline shack temperatures. However, it was also acknowledged that the success of such a project lies in including the beneficiaries in the planning and decision-making processes, as well as the provision of financial, educational and skills-training support to the Khayelitsha community both during and after the installation of the upgrades.