What is the main function of a roof?

The main function of a roof is to protect the interior from weather. This primary role ensures that the occupants and belongings within a structure are shielded from elements such as rain, snow, wind, and extreme temperatures. A well-designed roof provides an essential barrier that prevents water intrusions and helps maintain a stable indoor environment, which is crucial for comfort and the preservation of materials.

While enhancing energy efficiency, supporting ventilation systems, and contributing to architectural style are important attributes of a roof, they serve as secondary benefits derived from the roof's main function. The ability of a roof to effectively shield against the weather is fundamental to any building's structural integrity and usability, marking it as the most essential characteristic.