Adaptive thermal comfort and occupants behaviour in Mediterranean residential houses

This study investigates thermal comfort in residential buildings in Koper, Slovenia, located in a Mediterranean climate zone. The ASHRAE Class II protocol was employed, combining questionnaire-based surveys and field measurements to assess both subjective and objective indoor environmental parameters. A total of 580 valid responses were collected from 16 buildings between 2020 and 2021. The preferred temperature identified in this study was 21.2°C, which falls within the recommended range, whereas Griffith's comfort temperature was 19.8°C, slightly below the lower limit. Furthermore, the TSV index consistently exceeded PMV predictions, reinforcing the need for adaptive comfort models. The study also highlights critical indoor air quality issues: 83% of CO₂ measurements exceeded recommended thresholds, and 98% of humidity readings were outside optimal ranges in winter. The analysis of TSV (Thermal Sensation Votes) confirmed that respondents' preferred temperature is 21.2°C. The highest percentage, 97% of respondents, felt comfortable within the range of 19.5–20°C. The findings provide practical implications for building design and operation by demonstrating the importance of adaptive comfort strategies, ventilation practices, and climate-responsive renovation measures. The study provides evidence to support refining thermal comfort regulations and building standards based on local climatic conditions and occupant behaviour.