Design optimisation for embodied carbon and thermal performance of a courtyard house in the warm-humid climate of Ghana

Increasing global temperature points to the need to combat the intense heat in tropical regions. Mechanical cooling systems are one of the main ways to address this challenge. Ironically, using this approach further contributes to the issue of global warming. The courtyard design serves as a climate-responsive alternative that can effectively mitigate intense heat without exacerbating climate change. The effectiveness of the courtyard space in modifying the climate depends on various factors such as building materials and design configurations. As a result, optimising courtyard design configurations to enhance their climate adaptability is crucial, while simultaneously addressing embodied carbon emissions in new building construction to mitigate their impact on climate change. Adopting the life cycle thinking approach, this study sought to optimise a modern courtyard design to evaluate cooling load and embodied emissions in Ghana. The design was optimised for wall construction material, window-to-wall ratio, shading and courtyard eccentricity (degree of centre offset). The parametric study compared 2000 possible alternatives. The results showed that deep and small courtyards are optimum design configurations in enhancing the thermal and energy performance of courtyard houses in warm–humid climates. Walls made of rammed earth reduced embodied carbon by 12% and cooling loads by 16%, as compared to sandcrete block walls. The findings provide new knowledge to achieve a thermally efficient and comfortable contemporary courtyard housing design with low embodied energy suited to warm–humid climates, such as that of West Africa.