Roof Sheathing Thickness Requirements

Never attach roof sheathing with staples.

Roof sheathing thickness requirements.

Requirements for coastal construction are typically different than for non coastal areas. Over spaced sheathing no underlayment is used except at the eaves if eaves flashing is required. N the highest uplift forces occur at roof corners edges and ridge lines. Some departments do not have the man power to do roof sheathing inspection inspectors can not see everything and assume that the builder knows enough to do some things right.

Floor or roof sheathing conforming with this table shall be deemed to meet the design criteria of section 2304 7. Roof sheathing panel spacing hints. Loads will vary with the. 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.

Roof sheathing shall be structural wood panels plywood osb with a minimum five eighths inch thickness grade stamped for use and span. Sheathing type typically 15 32 inch or thicker panels are required in high wind areas. 8d ring shank nails should be used instead. The typical thickness range for sheathing is 3 8 to 3 4 inch.

Spacer type panel edge clips are available from some manufacturers. Minimum thickness most roofs will be sheathed in plywood at least 3 8 inch thick. Over solid sheathing use minimum no. Secure roof sheathing panels to the roof framing with 8d common nails spaced six inches on center at the edges and twelve inches on center at intermediate supports.

7 construction exceeding the minimum requirements6 osb or plywood is the minimum you can use without edge support. Installation details shall conform to sections 2304 7 1 and 2304 7 2 for floor and roof sheathing respectively. 1 inch 25 4 mm. N improved fasteners such as ring shank nails increase the uplift resistance of the roof sheathing.

Sheathing should be a minimum of 19 32 inch thick. Roof sheathing comes in grid marked 4 by 8 foot sheets and should be installed perpendicular to the frame. That will suffice on a roof with rafters set 16 inches apart with minimal roof loads. Where the sheathing thickness is greater than 15 32 inches roof sheathing is required to be fastened with astm f1667 rsrs 03 2 0 131 nails or astm f1667 rsrs 04 3 0 120 nails.