Evaluating the impact of building material selection on the life cycle carbon emissions of South African affordable housing

This study evaluated the life cycle carbon emissions of the two most common affordable housing designs primarily used in South Africa. It examined the impact of conventional, alternative and green building materials on life cycle carbon emissions of five main building components: building envelope, internal walls, flooring, windows, and roof systems. The EDGE application modelling software was used to estimate the life cycle carbon emissions of the various building materials and the overall houses. The comparison between the resulting carbon emissions of the three scenarios proved that modifying the building materials from conventional to alternative and green materials is able to reduce ~55% and ~75% of carbon emission of the construction phase, respectively and overall ~10% of life cycle carbon emission of the house. The findings, however, indicated that a change in building material has a more significant impact on the carbon emission in the construction phase than the operational phase. The results, therefore, confirmed the critical role of material selection in affordable housing as the main contributor to the life cycle carbon emissions, given the absence of heating and cooling systems in these housing types. Finally, the finding led to the conclusion that a change in material used for affordable housing alters the method of construction for the proposed materials and consequently lowers the lifecycle carbon emissions produced by the construction industry and improves the sustainability of houses and the housing sector in general.