Role of vernacular architecture in enhancing the environmental sustainability of the building sector

Abstract

Nepal's rapid urbanization, rural-to-urban transition, and economic growth have driven a major shift in building construction, moving from traditional methods using brick, stone, mud, and wood to contemporary Reinforced Cement Concrete (RCC) buildings. This transition in building construction practice raises critical questions about changes in the building life cycle energy use and emission. So, the study aimed to assess the life cycle energy consumption and carbon emissions (CO₂-eq.) of the typical traditional building types in Nepal namely: attached brick houses (ABH), isolated brick houses (IBH), and isolated stone houses (ISH).

The Life Cycle Assessment (LCA) of the Nepalese traditional building shows that the life cycle energy use of traditional buildings ranges from 3573 to 5864 MJ/m², with emissions between 438 and 681 kgCO₂-eq/m²—substantially lower than RCC counterparts. A crucial factor is the use of biogenic materials in traditional buildings, which can sequester −126 to −185.5 kgCO₂-eq/m² during their lifecycle, offering a natural mechanism for reducing carbon emissions. In Nepal, where the energy mix is predominantly hydropower and residential buildings have minimal operational energy demands due to limited space heating and cooling provision, embodied carbon becomes a decisive factor in evaluating the environmental impact of construction. Traditional building practices present a compelling strategy for reducing embodied energy and emissions, thereby supporting sustainable development. The study highlights the importance of leveraging traditional building methods to create a low-carbon future, particularly in contexts like Nepal where renewable energy resources and low operational energy needs align with the advantages of biogenic materials.