There is growing need for new buildings to support the urbanization and demographic boom in developing countries. These buildings should be environmentally friendly, economically accessible and, most importantly, thermally efficient. The latter aspect is particularly important when dealing with naturally ventilated buildings in hot-dry regions. For this purpose, the thermal design of walls based on compressed earth blocks (CEB) need to be studied in order to achieve optimal use of this material. The present study aimed at experimentally analysing the thermal performance of a test building which has three different design (wall layers) of external wall and two scenario of ventilation. Thermal sensors was used on the test building in order to determine the indoor and outdoor air temperature as well as the surface temperature of the walls. The results show that the location of wall layers influences the indoor climate. When CEBs layer is placed inside, it leads to the highest reduction of the indoor temperature fluctuations. When CEBs layer is placed outside, it presents the best opportunity to prevent overheating in building spaces mainly occupied at night. Regardless of the wall design, nocturnal ventilation is the most suitable strategy which leads to improving the indoor climate compared to continuous ventilation. It is highlighted that the occupancy pattern of the buildings’ spaces as well as the addition of the insulation layer to the CEBs walls are important factor to consider for the design of external walls.