AbstractThe new vision of Smart Cities drives policies regarding sustainability of urban environment in terms of reducing consumption, environmental impacts and improving energy efficiency and safety of building sector. The mutual interaction between buildings and the surrounding built environment can affect all these fields. In particular, the paper investigates this interaction in order to analyse the energy behaviour of buildings at urban scale and the effect on the outdoor comfort. To reach this goal a multi-level and multi-purpose model was developed based on a synergic and integrated bottom-up approach for both energy efficiency and outdoor comfort analysis. The energy analysis is based on the identification of reference buildings with known energy performances, defined sing information available at Public Authorities, statistical studies and data from field surveys. A multi-level parametric approach used for the outdoor comfort analysis allows to identify the Universal Thermal Climate Index (UTCI) and the related stress level of the district starting from the environmental data available at rural station. The model allows the estimation of the current energy and environmental behavior of the built environment and identifies possible renovation scenarios.