What is Sheathing? Sheathing is exterior grade lumber or boards used as a roof deck material. Exterior grade lumber or boards used as a roof deck material.
![GBAD Full Color.png]](https://help.gibraltarbuildingproducts.com/hs-fs/hubfs/GBAD%20Full%20Color.png?height=40&name=GBAD%20Full%20Color.png){kind=small}