Abstract

Numerous heritage buildings are being renovated across historical cities in Southeast Asia as part of conservation efforts. Many such buildings suffer from poor indoor daylight quality, negatively affecting occupants’ visual health. This study proposes a novel framework to analyze daylight quality in heritage shophouses using window-to-wall ratios and five metrics. Three typical shophouses with different shape factors (SF) are considered case studies. The shophouses were simulated in Rhinoceros®, Grasshopper®, ClimateStudio™ V1.9, and DIALux evo® to examine different window-to-wall ratios (WWR10–100), aiming to identify an optimal value for high-quality daylight within the buildings. The results show that West-facing (0°) buildings can have suitable indoor daylight, except in cases where a building has an internal courtyard. Increasing the WWR value improves most daylight performance metrics, except the ASE metric, which requires careful control through a reduced WWR–particularly in buildings with narrow and elongated layouts. For buildings with square-shaped and rectangular layouts, even a modest number of openings (WWR10–40) can meet most metrics suggested in LEED V3 and LEED V4 standards. This study serves as a guideline for developing building control regulations in historic urban areas to promote the sustainable adaptation of traditional shophouses.