The structural covering placed directly over framing members which also serve to transfer loads into the pitched chord truss. Wood structural panel sheathing is commonly sold and installed in 4’ x 8’ sheets.

OSB Sheathing
Oriented Strand Board—Manufactured from waterproof heat-cured adhesives and rectangularly shaped wood strands that are arranged in cross-oriented layers, similar to plywood. This results in a structural engineered wood panel that shares many of the strength and performance characteristics of plywood. Produced in huge, continuous mats, OSB is a solid panel product of consistent quality with no laps, gaps, or voids.
Wood structural panel roof sheathing varies in thickness based upon the spacing of the roof framing and the load that results from snow, etc.
OSB is stored off the ground on the job site.
Raised heel pitched chord trusses bear on double top plates and are connected to the wall with metal straps to resist wind uplift forces.
Pitched chord roof trusses are sheathed with OSB. Scissor trusses create a cathedral ceiling effect from inside the room.
Pitched chord roof trusses are manufactured with a large center opening that creates a closet off the master bedroom. The bottom chord of the trusses is wide, since it is also acting as a floor joist.
Plywood Sheathing
Plywood—manufactured from thin sheets of cross-laminated veneer and bonded under heat and pressure with strong adhesives. Plywood is also referred to as a wood structural panel.
Plywood Sheathing.
Structural Insulated Sheathing
Structural Insulated Panels—High-performance building panels for floors, walls, and roofs in residential and commercial buildings. Each panel is typically made using expanded polystyrene (EPS), or polyisocyanurate rigid foam insulation sandwiched between two structural skins of oriented strand board (OSB).
Structural Insulated Panels.