Influence of Building Orientation and Glazed Terrace Design on Passive Solar Heat Gain in Residential Buildings

Introduction/Objective This study investigates the influence of building orientation, geometric form, and glazed terrace design on passive solar heat gain and energy efficiency in low-rise residential buildings under Uzbekistan’s climate. The objective was to identify architectural and envelope strategies that reduce heating demand and improve indoor thermal stability. Methods The study combined theoretical heat-transfer analysis with field experiments on a single-story residential building in Zangiota District, Tashkent Region. Comparative analyses considered building compactness, surface-to-volume ratio, façade orientation, glazing configuration, and four external wall systems with different thermal resistances. Indoor and surface temperatures, relative humidity, and thermal responses were monitored using manual measurements, data loggers, infrared thermometers, and thermocouples over eight consecutive heating seasons (2017–2025). Results A dome-shaped configuration reduced the external envelope area by approximately 20% compared with a conventional rectangular form of similar volume. The best-performing multilayer wall system, incorporating cinder blocks, 150 mm reed insulation, and an external brick layer, achieved a thermal resistance of 4.30 m 2 ·K/W and reduced heating energy consumption by approximately 36% compared with conventional wall systems. Under clear-sky conditions, the south-oriented glazed terrace exceeded indoor air temperature by approximately 5–7°C. Discussion The results demonstrate that compact geometry, improved envelope insulation, and south-oriented glazing can synergistically reduce heat losses and enhance passive solar heat gain and indoor thermal stability. Conclusion Climate-responsive building orientation and geometry, combined with locally available insulation materials and passive solar spaces, provide an effective strategy for improving energy efficiency in low-rise residential buildings in Uzbekistan and similar continental climates.