Roof Sheathing Should Be Installed

In this case to keep the panel s strength axis perpendicular to the hip trusses the panels on the hip roof portion must be installed with their long dimension oriented up and down the slope.

Roof sheathing should be installed.

Roof sheathing comes in grid marked 4 by 8 foot sheets and should be installed perpendicular to the frame. In areas where the wind speed is greater than 130 mph nails for attaching the roof sheathing to intermediate supports should be spaced 6 inches on center for at least the first 48 inches from the ridges eaves and gable end walls. 24 inches on center the actual distance between panel supports measured along the slope is greater than the truss spacing. Sheathing is installed perpendicular to roof trusses.

The first thing we check is the thickness of the material used. 8d ring shank nails should be used instead. Sheathing should be a minimum of 19 32 inch thick. For plywood composite or osb boards installed on rafters it should be at least 5 8ths of an inch thick.

If the top chords of trusses or rafters are warped or bowed install blocking to straighten. This can be done with a straight piece of lumber 6 feet to 10 feet long or a long carpenter s level. Slide the sheet one rafter width over the end of the roof so the edge is centered on the next rafter offset one rafter spacing from the first piece of installed sheathing from the row below. Tongue and groove installations require thicker material at least 1 1 2 inches thick as they don t often require insulation and often double as the ceiling.

Local roof repair contractors inspect the sheathing during maintenance repairs and especially during roof replacement. Trusses or rafters should be shimmed as necessary to provide a level nailing surface. Then its condition is inspected.