Incremental production of urban space: A typology of informal design.

Informal settlement is a form of incremental urban design and planning that seems set to remain a primary mode of urban development in cities of the global South. Yet, we know very little about how incremental urbanism works. In this paper, we suggest a typology of increments as a conceptual lens for understanding the emergence of informal settlement morphologies. We consider the ways residents extend and renovate buildings at micro-spatial scales and identify typical increments of 'extend', 'attach', 'replace', 'divide', 'connect' and 'infill'. We also explore the informal rights and codes that govern the ways in which some increments encroach on public space – 'rights of way', 'air-rights' and 'the right to light and ventilation'. We engage with the paradox that while every increment is a form of upgrading, informal settlements often produce slum conditions. We suggest that the most effective knowledge base for slum upgrading practices lies in a better understanding of informal settlement as a mode of spatial production. • We have developed a typology of incremental design and construction, identifying typical increments of extend, attach, replace, divide, connect and infill. We have also explored the underlying informal codes or customary rules guiding generative processes with regard to extension and attachment. • Increments of change are at once the materiality of the productive capacity of informality and the expressive manifestation of resistance and anticipation. • While informal codes or rules are proscriptive and work through negotiation and consensus, they cannot necessarily prevent the emergence of slum conditions. • We need a change of mindset, not only from outcomes to codes and processes, but also from rigid to supple codes that can encompass the makeshift and temporary. • Enabling the productive capacities of incremental urbanism and constraining its destructive aspects are equally important when we wish to sustain adaptive capacities of informal settlement over time. [ABSTRACT FROM AUTHOR]