The thermal behavior of urban blocks is influenced by multiple factors, including climate, design, geometry, materials, and landscape elements. Optimizing these parameters is essential for sustainable and comfortable urban environments. This study investigates the thermal performance of an urban block with a courtyard (UBC) using a 1:10 scale experimental model built with Oriented Strand Board (OSB). The experiment examines the influence of surface coatings on thermal behavior in a naturally ventilated setting, with a focus on courtyard microclimates. A key objective is to assess how architectural form and material properties affect heat transfer between indoor and outdoor spaces. Results indicate that white cladding reduces the indoor-outdoor temperature difference to 1.78 ℃, demonstrating its potential for thermal comfort. However, a maximum temperature difference of 24.29 ℃ suggests substantial heat exchange, emphasizing the role of coatings in moderating urban microclimates. The results emphasize the critical role of coating materials and architectural form in modulating courtyard microclimates, offering valuable insights for urban designers and policymakers aiming to enhance thermal efficiency in dense urban environments.