Extemes of mixed-use architecture: a spatial analysis of vertical functional mix in Dhaka

Abstract The concept of mixed-use is now well-established as an urban design and planning principle that adds to the vitality, walkability and productivity of the city at neighbourhood scale. There is much less research on the dense and complex vertical mix of functions within buildings. This paper investigates the extremes of informal vertical mixing of functions within buildings in Dhaka, where commercial and retail functions often penetrate to upper floors and where access routes are often mixed with residential functions. A modified form of space syntax analysis is used to analyse and critique the mix of circulation patterns and functions in 15 complex mixed-use buildings. The plans and relational diagrams reveal how different functions are mixed or separated, and the relative spatial depth they penetrate from the street. Five primary circulation diagrams emerge with different degrees of informality in different districts of the city. Under conditions of informal adaptation, vertical functional mix produces benefits in the form of synergies but also problems of privacy and security. To engage effectively planners need a complex understanding of the interrelated spatial, social and economic logics involved.