Experimental investigation of RTS method to calculate heat gain on walls and flat roof

Multi-layered walls are commonly used building elements that have the potential to reduce cooling loads by improving thermal insulation. This paper investigates the potential of reducing cooling load using different types of multi-layered. For this purpose, a model of a small room (1.15 × 1 × 1 m) was constructed. A software code based on the radiant time series method was developed using MATLAB to extract heat gain results. The results were verified with other researchers, and there was a 0.89% error. Overall, the results show that using solid or hollow bricks in construction can be an effective way to reduce heat gain, where Wall-C achieved the minimum heat gain of 60.8 W m−2 compared to 66.207 and 71.225 W m−2 for Wall-A and Wall-B respectively. The reasons for this could be due to the insulation hollow area provided by the bricks, which tends to reduce heat transfer through the wall.