Minimum Roof Sheathing Thickness

1 inch 25 4 mm.

Minimum roof sheathing thickness.

The minimum plywood for roofing. Where the rafter spacing is 24 inches on center or less roof boards may be used that have a minimum thickness of 5 8 inch for solid sheathing and 3 4 inch for spaced sheathing. Never attach roof sheathing with staples. Floor or roof sheathing conforming with this table shall be deemed to meet the design criteria of section 2304 7.

8d ring shank nails should be used instead. The typical thickness range for sheathing is 3 8 to 3 4 inch. Many code requirements are not inspected. 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.

Roof sheathing comes in grid marked 4 by 8 foot sheets and should be installed perpendicular to the frame. 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. Rafters run from the peak of the roof. 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.

2 the thickness or rating of roof sheathing on a roof not used as a walking deck shall conform to either table 9 23 15 7 a. Sheathing should be a minimum of 19 32 inch thick. 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.

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. According to 2009 irc table r803 1 minimum thickness of lumber roof sheathing. You would go to table r503 2 1 1 1 to determine minimum nominal panel thickness.