Urban heat islands (UHIs) are a defining challenge of contemporary cities, exacerbating thermal stress and increasing energy demand in the built environment. While UHI research has traditionally focused on quantifying air and surface temperature differences between urban and rural settings, there is limited integration of microclimatic effects into building energy performance, particularly within advanced energy-efficient frameworks such as Passive House and nearly zero-energy building (nZEB) standards. This study proposes an original Local Urban Heat Island Index (L-UHI) that operationalizes multiple urban design and landscape parameters—vegetation typologies, water surfaces, shading geometry, surface materials, and anthropogenic activity—to estimate localized thermal elevation relative to a rural baseline. Drawing on novel high-resolution drone thermal data and urban morphology metrics, the L-UHI model aggregates design-driven cooling and warming factors into a composite index that captures site-specific microclimatic impacts.
Beyond proposing a scalable methodology for urban project evaluation, the research advances a quantitative linkage between L-UHI and building energy performance by translating localized temperature amplification into its potential impact on heating and cooling demand. By incorporating L-UHI as a modified boundary condition within building energy assessment frameworks, the study explores how microclimatic intensification may alter annual energy consumption (kWh/m²·year) in high-performance buildings, including Passive House and nZEB standards. Rather than treating urban climate and building efficiency as separate domains, the proposed approach establishes a methodological bridge between urban morphology and energy modeling, enabling the estimation of climate-sensitive performance deviations at the project scale. The framework thus connects urban design decisions with measurable implications for energy demand and thermal stress, contributing to more integrated strategies for climate-adaptive urban development.
