Beyond Energy Labels: A Bioclimatic Index for Passive Architecture-Sensitive Assessment of Urban Residential Buildings

Abstract

Improving the energy performance of residential buildings is essential for achieving climate neutrality goals, yet conventional Energy Performance Certificates (EPCs) often fail to account for the climatic and urban morphological factors that shape real-world energy demand. This study introduces a bioclimatic index that integrates urban morphology, microclimate and energy performance to evaluate building adaptability with climate sensitivity. Central to this framework is the concept of acclimatization distance, the thermal gap between indoor comfort and outdoor conditions, which serves as a proxy for thermoclimatic demand. Using geographic information systems (GIS) and multi-criteria decision-making (MCDM), the index incorporates factors such as building height, road surface area, Sky View Factor (SVF) and proximity to green-blue infrastructure, tested with empirical data from 4,954 residential buildings in Zaragoza, Spain. The results reveal a consistent alignment between the bioclimatic index and acclimatization distance, particularly in winter and over annual periods. Key urban morphology factors, especially building height and road surface area, proved to be the main drivers of bioclimatic performance. The study also highlights the limitations of existing EPC frameworks, which fail to integrate passive architectural strategies and contextual microclimatic factors that critically affect energy demand and comfort. These findings underscore the need for climate-sensitive performance tools that move beyond standardized metrics. The index offers valuable applications for climate-responsive urban planning and adaptation strategies, enabling planners to optimize land use, estimate the possibilities for adaptation to outdoor thermal comfort and reduce energy reliance.

Keywords: Acclimatization Distance, Bioclimatic Design, Energy Efficiency, Multi-Criteria Decision-Making (MCDM), Residential Buildings