Adaptive Thermal Comfort of Planned Low-income Housing of a Developing Country: Case of Kigali, Rwanda

Abstract

Global warming is expected to raise the average temperature of the tropical region by up to 3?4°C in the next 70 years. Due to the vulnerable living conditions that are predominant in mostdeveloping countries in the region, this will dramatically affect the indoor thermal performanceof exclusively, naturally ventilated buildings that form the majority of residential buildings inless-industrialized nations. In addition, the lack of knowledge about the built environment andthermal comfort design guidelines may significantly affect locals’ health and well-being,especially among low-income groups. This study evaluates the thermal performance of lowincomehousing that were constructed as a governmentsponsored project for urban revitalizationin Kigali, Rwanda. Dynamic thermal simulations are carried out through EnergyPlus softwareusing the DesignBuilder program as user interface. Annual discomfort hours and discomfortdegree-days are calculated using the ASHRAE 55 adaptive comfort model. The results indicatepoor thermal environmental conditions in this planned low-income housing structure. Indooroperative temperature is outside the adaptive comfort range for about 70% of time annually with955.3 discomfort degree-days. The roof was found to be the key element causing indoortemperature to exceed the upper comfort temperature threshold, while wall material mostlyinfluenced indoor temperature below the lower comfort temperature limit.