Effect of Courtyard Building Morphology and Internal Facade Transparency Ratios on Energy Performance in Hot-Dry Climate Regions: The Şanlıurfa Case Study

Abstract

This study examines the Energy Performance of courtyard residential typology in Hot-Dry Climate Regions using Numerical Analysis Methods, focusing on Courtyard geometry (Width-to-length ratio), Number of storeys, and Window-to-wall ratio (WWR) parameters. Within the scope of the study, three different building models (single-storey, two-storey, and three-storey) were created for Şanlıurfa province, which represents Türkiye's hot-dry climate characteristics. Building envelope thermal transmittance values were determined according to TS 825:2024 standards; in all models, the Building footprint area and courtyard area were kept constant, and the Courtyard width-to-length ratio (W/L) was parametrically varied within the range of 0.25–3.00. Window-to-wall ratio scenarios of 0%, 50%, and 100% were defined only for facades facing the courtyard; a total of 108 different scenarios were simulated using DesignBuilder (EnergyPlus engine) software. The findings obtained under Şanlıurfa's climatic conditions and the defined model assumptions can be summarized as follows: In terms of Courtyard geometry, it was determined that square and near-square forms (W/L ≈ 1.00–1.25) exhibited the lowest Energy consumption in all Number of storeys scenarios for completely Opaque (WWR: 0%) scenarios. With the increase in Window-to-wall ratio, the optimum Courtyard geometry shifted from square forms to wide rectangular forms (W/L ≈ 2.25); the WWR ≈ 50% scenario was found to produce the lowest total Energy consumption value (30.37 kWh/m²) among all parametric combinations examined. In terms of building height, it was determined that in completely Opaque buildings, three-storey structures exhibited an average of 13–15% lower Energy consumption compared to single-storey structures, and Mass compactness has the potential to reduce Energy consumption. However, it was observed that this relationship transformed with increasing transparency ratio, and under certain geometric conditions, single-storey structures could achieve lower consumption values. The simultaneous use of Narrow-Long Courtyard geometry (W/L: 0.25) and high transparency ratio (WWR: 100%) was found to create the most unfavorable combination in terms of Energy Performance, with the annual total Energy consumption reaching 44.43 kWh/m² in this scenario. All findings and design parameter recommendations presented in this study are valid within the framework of Şanlıurfa's climatic conditions, TS 825:2024 building envelope standards, and the defined model assumptions, and it is recommended that the relevant conditions be evaluated separately before transferring to different climate regions or building typologies.

Keywords

• Courtyard building
• Energy performance
• Hot-dry climate
• Courtyard shape factor
• Window-to-wall ratio
• Parametric simulation

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