Minimum Roof Sheathing Thickness

Many code requirements are not inspected.

Minimum roof sheathing thickness.

Floor or roof sheathing conforming with this table shall be deemed to meet the design criteria of section 2304 7. And for wood structural panel sheathing r803 2 2 allowable spans. The minimum plywood for roofing. Thickness or rating 1 the thickness or rating of roof sheathing on a flat roof used as a walking deck shall conform to either table 9 23 14 5 a.

Roofs are framed with rafters or trusses which are rafters joined by internal braces so they install as a single component. The international code council icc is a non profit organization dedicated to developing model codes and standards used in the design build and compliance process. You would go to table r503 2 1 1 1 to determine minimum nominal panel thickness. Never attach roof sheathing with staples.

Roof sheathing comes in grid marked 4 by 8 foot sheets and should be installed perpendicular to the frame. According to 2009 irc table r803 1 minimum thickness of lumber roof sheathing. Building codes for roofing reqiure a minimum 1x4 and the spaces between battens should not exceed 3 1 2 inches figure 2 46 wood shingles over spaced sheathing and figure 2 47 wood shakes installed over wood sheathing are illustrated below. Osb roof decking thickness 7 16 1 2 or 5 8 if were using osb we get 9 16 we dont worry about getting both 7 16 and 9 16 for walls then the roof we just get all of the same.

8d ring shank nails should be used instead. 1 inch 25 4 mm. Rafters run from the peak of the roof. The typical thickness range for sheathing is 3 8 to 3 4 inch.

This way no worrying about grabbing scraps to fill in small spots and not having the correct thickness. Installation details shall conform to sections 2304 7 1 and 2304 7 2 for floor and roof sheathing respectively. The international codes i codes are the widely accepted comprehensive set of model codes used in the us and abroad to help ensure the engineering of safe sustainable affordable and resilient structures.