Scalable Computational Framework for Evaluating Residential Energy Retrofits across Diverse Climates and Occupant Behaviors

Residential energy retrofits are crucial for achieving national energy efficiency goals, yet their large-scale implementation is hindered by diverse climate conditions and occupant behaviors. This study introduces a scalable computational framework to address this challenge by integrating the National Residential Efficiency Measures (NREM) database with International Energy Conservation Code (IECC) prototype building models. The framework enables flexible scenario analysis, from individual buildings to large-scale, cross-regional applications, by systematically evaluating retrofit effectiveness under varied climate zones and occupant behavior patterns. A case study of a representative two-story, single-family house is conducted to assess 16 retrofit measures across eleven scenarios of diverse climatic and behavioral conditions. The results show that wall insulation and HVAC system retrofits yield the highest source energy savings, while HVAC and lighting upgrades offer the shortest payback periods. Conversely, other envelope and appliance retrofits provide marginal contributions to energy reduction and less attractive returns on investment. The analysis further reveals that climate zone and window-opening behavior are dominant factors influencing both energy savings and cost-effectiveness. Notably, retrofits in marine climates exhibit lower economic returns due to milder thermal loads, indicating the necessity of large-scale, regionally-tailored building retrofit strategies. By efficiently capturing the impact of environmental and behavioral factors, this framework offers a practical and extensible foundation for developing regionally adaptive residential retrofit strategies.