Testing the housing and transportation affordability index in a developing world context: A sustainability comparison of central and suburban districts in Qom, Iran

•True household affordability should reflect combined housing and transport costs.•This study measured total housing and transport costs for various locations in Qom City, Iran.•Results show that suburban households spend significantly more than households in the central locations.•This illustrates the feasibility of developing a housing and transportation cost index in developing country cities.

Housing affordability is an important policy goal. However, housing is not truly affordable if located in an inaccessible area with high transportation costs. Increasing the supply of affordable housing in accessible locations helps achieve multiple planning objectives: it reduces transportation costs, improves economic opportunity for disadvantaged groups, reduces accident risks, conserves energy and reduces pollution emissions. In recent years researchers have developed analysis methods for measuring total housing and transportation costs for different locations within cities, called a Housing and Transportation (H+T) Affordability Index. This study applies this type of analysis in Qom City, Iran. The results indicate that suburban-area households spend more than 57% of their monthly income on housing and transport, significantly more than the 45% spent by households in the central district. This is consistent with research results in other urban areas. This illustrates the feasibility of applying housing and transportation affordability analysis in developing country cities to help identify truly affordable and sustainable development.