Bioclimatic Enhancement of a Low-cost Earthen Dwelling in Niger Through Comfort Optimisation and Local Skills-based Technologies

[EN] The paper presents the outcomes of research conducted within the framework of the "Urbanisation4Change" project in Niger, implemented between 2021 and 2023 by a consortium coordinated by the CISP Ngo, and funded by the European Union Emergency Trust Fund (EUTF) for Africa under the D.E.S.E.R.T. Programme. The study, carried out by the Politecnico di Torino, focused on the bioclimatic optimisation of an earthen housing prototype, employing passive architectural strategies and technologies tailored to the specific social, cultural, and economic context. The prototype, proposed by CISP, was designed for a new settlement intended to accommodate migrants and local populations with limited access to housing on the outskirts of the city of Agadez. Following an extensive review of the literature and a detailed analysis of the climatic and environmental conditions in Agadez, a set of passive bioclimatic strategies aligned with vernacular construction practices was identified. By means of an adaptive thermal simulation model, the indoor comfort conditions of the housing prototype were assessed, and the impact of each enhancement strategy was systematically evaluated. Subsequently, multiple scenarios were elaborated, combining the most effective strategies to maximise improvements in indoor thermal comfort. Furthermore, a field investigation into the availability of local construction materials and artisanal skills enabled the validation of the feasibility of the selected strategies, as indicated by the simulation outcomes. The identified strategies were then developed to the technological scale, actively involving local artisans in the design and implementation processes. As a result, prototypes for two of the three technologies were successfully produced on-site.