May only be used where the roof live load design snow load is 40 psf or less.
Roof osb sheathing 24 truss spacing.
If the wood structural panels are tightly butted there is no room for expansion and buckling can occur.
Spacer type panel edge clips are available from some manufacturers.
Sheets of 7 16 inch thick with no edge support can be used in an area where the snow load is 30 pounds per square foot.
For rafters spaced 20 or more inches apart 1 2 or 5 8 inch plywood is recommended.
If the roof live load exceeds 40 psf alternate roof sheathing must be utilized.
Roof sheathing panel spacing hints.
These little changes can effect the maximum spans allowed by code and you can find the label stamped on the sheathing.
I would first verify what you actually have by looking for a stamp on the roof sheathing.
That can mean costly time consuming callbacks.
Typical types of wood used for roof sheathing are oriented strand board known as osb and plywood the most popular being osb.
Boards require a minimum of two nails per truss while sheathing requires six nails due to face width and nail spacing.
Lay sheets in rows with the long edge horizontal to the roof bottom.
Use a 10d box 0 128 inch by 3 inch nail as a spacer to gauge 1 8 inch edge and end spacing between panels.
Plywood and oriented strand board osb like all wood products will expand or shrink slightly with changes in moisture content.
Each of these factors plays a role in determining how many nails you ll need to use per board during roof sheathing application.
The minimum osb panel size is 24 inches in any direction and each sheet end must rest on a rafter.
A structure s roof truss spacing can vary from every 12 to 24 inches.
Apa e30 01 american plywood association engineered wood construction guide e 30 indicates that 7 16 osb for roof sheathing with supports 24 o c.
With edge support and the same snow load 3 8 inch osb can be used.
The most common rafter spacing is 24 inches and 5 8 inch plywood is recommended for that.
Provide a 1 8 inch gap.