Carving a niche in building energy using modern vernacular house with passive wall materials - A multi-criteria decision-making framework

The building sector, one of the world's largest energy consumers, includes vernacular houses that offer good living conditions. However, increasing population and energy demands have caused vernacular houses to impact the ecosystem negatively, thus losing popularity. Passive design features can alleviate this problem but entail several factors and alternatives. This study aims to develop a fuzzy-based multi-criteria decision-making framework for selecting an optimal wall material for vernacular house that satisfies the technical, economic, environmental and social factors. Seven different wall materials, along with governing factors like room temperature, humidity, cooling and heating loads, cost, comfort index, CO2 emission, job creation and social acceptability, are considered. Four fuzzy-based decision-making tools are used, followed by sensitivity analysis to examine the results. A test cell of an established 3BHK vernacular house is made using design-builder and is simulated with Energy plus software. The error indices confirmed the design-builder model's accuracy, with NMBE and CV-RMSE values for room temperature and relative humidity both under 1 %, well within ASHRAE 14's threshold limits. From the results, cinder concrete is found as optimal passive wall material, resulting in lower cooling and heating loads and CO2 emission by 0.68 %, 9.64 %, and 2.27 %, respectively, than traditional vernacular house.