Comparison of energy-effective components of a building envelope with natural fibres and straw bales: a case study in the Sierra Region of Ecuador

The construction of housing and infrastructure is one of the largest contributors to pollution, as it accounts for around 21% of global CO 2 emissions. Reducing the impact of building materials is key to curb climate change. This paper evaluated hygrothermal performance of a case study, Natura y Arte house, built in the Ecuadorian Andes region using straw bales and natural fibres in the years 2021-2022, at 3200 meters above sea level, with mostly constant temperatures throughout the year with great variations from day to night. For this, the research applied on-site monitoring of exterior and interior areas and six surfaces of various components of the building envelope. Walls, floor, and roof assemblies were 2D-FE modelled, including straw bale walls rendered with clay, insulated floor, and composite roof with various fibres. Main results show that straw bale walls provide higher insulation over the other building components, U-value of 0.24 W/m²K was met. The passive design also contributed to a highly insulated building envelope with minimal heat loss, creating a consistently comfortable indoor environment while significantly reducing energy consumption.