Energy and thermal performance of a typical rammed earth residential building in Western Australia

Rammed earth (RE) constructions are gaining relevance worldwide for their reduced embodied energy when local materials are employed, and the material is stabilised with sustainable stabilisers or with a low quantity of cement. Besides, RE construction offers good thermal performance under specific climatic and technical conditions. However, the material is characterised by poor thermal resistance, which led to the common practice of insulating RE walls. This study focuses on the effect of including natural fibres (Spinifex) on the thermal properties of cement stabilised RE made of crushed limestone. This study integrates an experimental approach investing the thermal properties of RE with a building dynamic simulation approach employed to assess the energy performance of a typical residential building against the Australian National Construction Code's requirements. The thermal performance of the building is assessed under different climate-specific adaptive thermal comfort models regarding the Western Australian climates. The results show that the inclusion of Spinifex fibres positively affects the material's thermal properties. Besides, the study illustrates a considerable difference in the evaluation of the discomfort hours when climate-specific models are adopted compared with internationally accepted standards.