As a result of Apartheid, there are millions of displaced communities living in South African informal settlements. Although Government launched the ‘In-situ Upgrading of Informal Settlements’ scheme in 2010, to date only a couple of prototype transitional designs have been developed – none of which address all the housing issues expressed by residents (i.e. extreme indoor temperatures, winter flooding, risk of fires spreading). Therefore, this research focused on assessing sustainable incremental upgrade options for the existing housing stock in these settlements – with the aim of substantially improving living conditions without employing the classical ‘eviction, destruction and rebuilding’ strategy normally used for slum-upgrading schemes.