As an inseparable component of building exterior envelope, the roof serves critical roles in energy conservation, controlling moisture accumulation inside structures, managing heat dynamics and defence for indoor rooms against wind and rain outside. As part of the built environment, the roof has always been more than just a shield. It reflects cultural development and technological progress. The growth of human civilization has long been put on the roof s head even if not as palpably related to it as this saying might suggest. The development of human civilization and the history of roofing are closely related. From the first shelters made of natural materials to today's most sophisticated technology, roof development has played a notable role in architectural history. Roof as an integral component of architectural design, have evolved through time, from basic shelters to intricate technologically advanced structures. In composite climates, characterized by both hot-dry and warm-humid conditions with significant seasonal variations, maintaining thermal comfort in urban residential buildings poses a unique challenge. Among the various building envelope components, the roof plays a pivotal role in mediating heat gain and loss. This paper explores the significance of roofs in achieving thermal comfort in composite climate zones, examining design strategies, material choices, and technological interventions that enhance building performance. Emphasis is placed on passive design principles and their impact on indoor environmental quality, energy efficiency, and occupant well-being.