What is the primary function of a roof's sheathing?

The primary function of roof sheathing is to provide structural support for the roofing materials installed above it. Sheathing is typically made from wood, plywood, or oriented strand board (OSB), and it serves as a solid base that anchors the roofing. This structural support is essential as it helps to distribute the weight of the roofing materials and endure the loads, such as snow, wind, and rain, ensuring the roof's integrity.

While sheathing can contribute to some degree of insulation and may also aid in creating a barrier against weather, its main role centers on supporting the roofing system. The aesthetic appeal of the roof is generally influenced more by the final roofing materials than by the sheathing itself. Hence, its primary purpose remains as a supportive structural component within the roofing assembly.