What does the term "sheathing" refer to in roofing?

Sheathing refers to the board material that provides a surface for roofing materials to be installed upon. This layer is typically made from plywood or oriented strand board (OSB) and serves several critical functions in a roofing system. It acts as a base for attaching the roofing covering, adds structural integrity to the roof, and helps with the distribution of weight across the underlying rafters or trusses.

In addition to its structural role, the sheathing also contributes to the overall weather resistance of the roof system by providing a barrier against rain and wind, ensuring that water does not penetrate into the building's interior. The sheathing is usually installed from the eaves to the ridge of the roof and is a fundamental component that supports the roofing material directly above it.

Understanding the role of sheathing is crucial for anyone working in roofing, as it is integral to proper installation and maintenance of roofing systems.