Building Volume per Capita: A Crowding Metric of Housing Disparities in Gauteng, South Africa

In South Africa’s largest city region, located in the province of Gauteng, a key condition of inequality is that high-income households live in large houses while low-income households live in much smaller accommodation. Innovations in earth observation have enabled the modelling of building volumes in cities and this allows for new ways of assessing housing inequalities in Gauteng. This study calculates building volume per capita (BVPC) for the province as an indication of the volume of residential space in which individuals live. It offers five analyses using this data. First, mapping this metric illustrates that townships, informal settlements and inner city high-rise areas have cramped conditions of less than 10 cubic metres per person, while suburbs have a much higher building volume per capita. Second, the article shows that this metric complements traditional calculations of crowding, such as the number of people per room. Third, it calculates the relationship between BVPC and income and shows that the lower-earning three-fifths of households in the province occupy just 13% of the province’s residential building volume, while the higher-earning two-fifths occupy 87% of the province’s building volume. Fourth, it calculates that 51% of residential hexagons in the province fall below the threshold of adequately sized housing as defined by South African housing standards. Finally, it shows that areas that fall below the threshold have a higher proportion of informal housing.