Natural cooling and heating strategies have gained significant attention due to their ability to dissipate heat without electricity, particularly through radiative cooling (RC), especially in tropical climate areas, is essential in achieving sustainable and energy-efficient architecture. However, normal methods are often limited due to some environmental factors such as sunlight, rainfall and also snowfall constrained their effectiveness. To control these factors behaviour, we study about the thermal performance of two exterior wall materials—weather paint and red gutka bricks (Multani Tiles) during daytime or under high temperature through an integrated experimental and computational approach. The weather paint reflects almost 60-70% of sunlight depends upon their thickness and texture. Also, the red gutka bricks reduce temperature from 5°C - 10°C on similar properties. Experimental investigations include building-controlled sections of walls with both materials and capturing surface temperature variations using an infrared heat gun under different weather conditions. Simultaneously, four parametric building models have been developed in Revit, two for hot and two for cold climates, incorporating advanced passive design strategies such as optimized orientation, thermal mass integration, and adaptive insulation techniques. A comparative energy performance assessment is performed using Revit's simulation tools to assess the impact of wall material selection on thermal performance and indoor comfort levels. By combining experimental results with synthetic energy modelling data, this study offers a significant understanding of material efficacy in passive climate adaptation for sustainable environmentally friendly green practices aligned with climate-responsive design principles.