Optimal Window-to-Wall Ratio (WWR) for Perceived Satisfaction with Natural Ventilation: A Post-Occupancy Evaluation in Affordable Housing of Kolkata, India

This study’s purpose was to identify the optimal Window-to-Wall Ratio (WWR) that maximises homebuyers’ perceived satisfaction with natural ventilation in affordable housing in the hot and humid climate of Kolkata, India. The methodology employed a rigorous, user-centric, quantitative approach. Data was gathered through a large-scale post-occupancy survey, collecting 383 valid responses from residents across 32 affordable housing complexes. Perceived satisfaction with natural ventilation was quantified using the Percentage of Scale Maximum (%SM) method from five-point Likert-type scale responses. Residents’ perceived satisfaction was correlated with the measured WWR of each complex. Using polynomial regression, a predictive mathematical model was derived to assess the non-linear relationship. The findings identified an optimal WWR range of 24–33%, with the mathematical peak satisfaction (at 97.5%) occurring at a WWR of 33.31%. Beyond this range (either below or above), the predictive mean satisfaction falls. The originality of this research is its innovative integration of perceived satisfaction with a quantifiable design parameter (WWR) in the affordable housing sector, shifting the research paradigm from a traditional, energy-based assessment to a human-centric adaptive comfort model, and using a predictive mathematical model to calculate optimal WWR based on post-occupancy residents’ perceived satisfaction in a hot and humid climate.