Clustering the built form at LAU2 level for addressing sustainable policies. Insights from the Belgium case study

Population growth has determined two different types of urban development: the vertical growth, tending to compactness, and the horizontal one which privileges a more dispersed and sprawled expansion. Those two urban forms have different impacts on environmental sustainability influencing, among others, the microclimate conditions of a city, the energy demand and its economic cost, and the provision of Ecosystem Services. European policies are oriented towards sustainable development of urban areas reducing the environmental footprint and restoring degraded ecosystem through a Green infrastructure deployment. Understanding the urban form, and specifically, the typology of the building form is crucial for policymakers and urban planners to define strategies for a higher degree of sustainability. The lack of data and the heterogeneity of information across Europe on the built form have hindered the operationalisation of European strategies and their downscaling into national or regional policies. The paper aims to fill this gap proposing a methodology based on a cluster analysis that estimates the built form of Belgium at LAU2 level for addressing single specific actions towards environmental sustainability goals. The cluster analysis uses data traditionally surveyed by national censuses, ensuring the replicability of the method for the upcoming 2021 census, and also the opportunity to update it continuously.