Spatial Metrics to Investigate the Impact of Urban Form on Microclimate and Building Energy Performance. An Essential Overview

The spatial configuration of cities has recently been the subject of several studies in a variety of disciplines, including geography, urban ecology, urban design, and urban and building physics. As a reaction to the demanding need to reduce the environmental impact of cities, research efforts have focused on the unintended interaction between urban form, microclimate and energy both with diagnostic and design perspectives. The above-mentioned interaction has required the introduction of several metrics able to measure and characterize urban form at a different scale (built form, density, typology, settings, etc.) and to act as performance indicators in microclimate and energy studies. The proposed section puts the issue in an interdisciplinary perspective, addressing the ability of spatial metrics to predict local climate, thermal comfort and energy demand. Basic knowledge of urban morphology and a systematic review of most common metrics are presented and discussed. Then a framework for understanding the capability of existing research methods for microclimate and energy performance assessment is proposed. Finally, critical evaluation on the relevance and roles of urban metrics for supporting urban analysis and fostering climate-responsive design is developed in order to highlight current limitations and offer suggestions for further progress in the field.