A simulation-based study using boundary conditions of a thermal response for common building materials in a low-income housing for Kampala, Uganda

Ibrahim S. Madugu , Emeka Christian Madubuko , Isah B. Yabo, Abubakar Abdulkarim, Ibrahim M. Ribah , Aisha L. Bagiwa, Aminu U. Yabo, Yinusa A. Adediran, Benjamin J. Olufeagba

Indoor thermal comfort is still a major issue in low-income housing in tropical urban areas like Kampala, Uganda, where passive design techniques are frequently the only practical way to manage heat. A boundary-condition-based thermal simulation of popular building materials, such as concrete walls, plastered brick walls, thatch roofing, and dark and light-colored metal roofs, is shown in this paper. Monthly surface temperature rise ([[EQUATION]]) and indoor air temperature rise ([[EQUATION]]) were calculated over the monthly average sun exposure duration using local climatic data, which included solar irradiance, wind speed, and ambient air characteristics. According to the results, light-colored metal roofs minimise surface heating by more than 60%, while dark-coloured metal roofs create significant heat gain ([[EQUATION]] > 10,000 °C under simplified models). Thatch roofs performed better thermally because of their large heat capacity and low thermal conductivity. Thermal inertia from concrete and brick walls hinders heat transport and could cause discomfort at night if ventilation is inadequate. For reasonably priced tropical homes, the study emphasises the necessity of careful material selection and colour adaptation in passive thermal design. These observations help East African cities make evidence-based decisions on sustainable building, architectural design, and housing policy.

Keywords

building materials, solar radiation, absorption energy, boundary conditions