This study examines the economic implications of energy inefficiency in the real estate sector, focusing on the risk of asset stranding resulting from evolving regulatory and market conditions. Considering the European Union’s Directive (EU) 2024/1275 and increasing market preferences for energy-efficient buildings, properties with substandard energy performance face growing devaluation risks. This study presents a quantitative framework for assessing the loss of property value resulting from energy inefficiency. The model incorporates three key dimensions: market devaluation, excess operational costs, and CO₂ emission-related penalties. Through market analysis and financial discounting techniques, this framework evaluates the cumulative financial impact of energy underperformance over a defined time horizon. The results indicate that inefficient buildings are becoming increasingly vulnerable to economic obsolescence, particularly as energy prices increase and carbon pricing mechanisms are implemented. These findings underscore the urgency of energy retrofit interventions to mitigate financial losses and preserve asset value. This study contributes to the ongoing climate-aligned real estate investment discourse and provides a decision-support tool for property owners, investors, and policymakers.