Embodied impacts of traditional clay versus modern concrete houses in a tropical regime

The environmental impacts of typical residential houses in Indonesia have not been assessed, although the expanding use of material – both locally fabricated and imported – has potentially created damage locally and regionally. This study focuses on two commonly used building envelope materials in Indonesia, the more traditional clay roof and clay bricks, and the more recently popular concrete block and concrete roof. The direct and indirect emissions resulting from the material use in buildings derived from the production process, transportation and construction are calculated. Cement-based houses are seen to be higher impact in the categories of abiotic depletion, global warming and human toxicity, whereas clay-based houses perform worse on acidification, eutrophication and photochemical oxidation. The analysis indicates that the reduction of weathering and the improvement of small-scale production processes in clay buildings could significantly improve the embodied impacts, making clay a more environmentally benign material across the life cycle. Furthermore, the analysis shows that if current trends continue, by 2030 the global warming impact from cement-based houses is predicted to contribute an additional 9 million tonnes CO2-eq compared to if all houses used traditional clay materials.

► Cement houses performed worse in global warming (3 times than clay houses). ► Mortar is responsible for the high percentage of AdP (abiotic depletion potential). ► Clay houses performed worse on acidification and photochemical oxidation. ► CO2 site emission from production of cement is 9 times higher compare to grid emission. ► Cement production process accounted the biggest percentage of emission emits.