The answer to 'roof decking or roof decking' is that roof decking and roof sheathing are two distinct components of a roof system. Roof decking refers to the structural layer that provides the foundation for the roof, while roof sheathing is the material that covers the roof decking and provides a surface for the roofing material.
Roof decking is typically made of plywood, oriented strand board (OSB), or solid wood boards. It is responsible for supporting the weight of the roofing materials, as well as any snow or other loads that may be placed on the roof. Roof sheathing, on the other hand, is usually made of plywood or OSB and is installed over the roof decking to create a smooth, even surface for the roofing material to be applied.