Application of sustainable prefab walling panels in erection of a toilet unit at a rural village

Industrialization has made solid waste disposal a challenge. Utilizing locally available industrial by-products in construction is a sustainable approach. Prefabrication is one of the innovative technologies approved by the Indian Government through which volumetric mass construction was made possible with effective cost and time savings. This study focusses on developing a lightweight prefab walling material that can replace the commercially available walling materials such as red clay and fly ash brick masonries. An agro-industrial by-product, co-fired ash is introduced into the mix design by partially replacing 10% of the fine aggregates. Waste expanded polystyrene beads are used to achieve lighter density and thermal insulation. Fly ash and cement are blended in equal proportions as cementitious ingredients. Crushed sand is completely replaced with river sand. Several mixes were tested for their density and compressive strength for finalizing the optimum mix. This was further tested for physico-mechanical, durability, and thermal properties. These properties are compared to the commercially available walling materials. Based on the results, the final lightweight mix is found to be around 18% and 27% lighter, 1% and 8% stronger, & 68% and 62% less thermally conductive than the red clay brick and fly ash brick respectively. As the developed product is suitable for construction, a prefab toilet unit is constructed at a rural village named Wadhona, Nagpur district, India. It is a part of the Clean India campaign initiated by the Indian government. Prefab elements are cast, stacked, and cured for 28 days. Later, these are transported to the site and erected within 2 days. The total construction and erection cost is similar to the Government approved technique. Thus, the developed end-product is found to be lightweight, sustainable, thermally conductive, and quick in construction at an affordable cost.