Climate-Sensitive Daylighting Design in India: Integrating Passive Strategies for Sustainable Building Performance

Daylighting plays a vital role in reducing building energy demand while ensuring visual and occupant comfort across India's diverse climates. This review synthesizes findings from 31 peer-reviewed studies published between 2015 and 2025 that analyze daylight performance through climate-based simulations, optimisation approaches, and field validation. Evidence across major climatic zones and building typologies reveals consistent design patterns and methodological developments. Moderate window-to-wall ratios of about 16%–20% repeatedly deliver balanced daylight autonomy and glare control, especially when paired with orientation-responsive shading. Courtyard configurations and overall building form were found to strongly influence vertical daylight distribution, with optimized height-to-width ratios enhancing spatial daylight autonomy by up to 93%. Dynamic shading systems and multi-objective optimisation frameworks outperform isolated parametric studies by more effectively resolving daylight, glare, and energy trade-offs, achieving lighting energy savings of roughly 26%. Vegetation layers and surrounding obstructions also affect daylight penetration and glare, though urban-scale modeling remains limited. Although climate-based daylight metrics such as sDA, UDI, and ASE are increasingly adopted, cross-climatic benchmarking, uncertainty analysis, and standardized validation procedures require further development. Emerging human-centric metrics, including vertical illuminance and circadian performance, show promise but are not yet systematically integrated.