Minimum Sheathing Thickness Roof

Many code requirements are not inspected.

Minimum sheathing thickness roof.

Minimum roof sheathing thickness excerpt roof sheathing thickness rafter truss spacing 24 in. 140 wind speed mph 150 mph 160 mph minimum sheathing thickness inches exposure b 7 16 24 16 15 32 32 16 19 32 40 20 minimum 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. Installation details shall conform to sections 2304 7 1 and 2304 7 2 for floor and roof sheathing respectively.

Floor or roof sheathing conforming with this table shall be deemed to meet the design criteria of section 2304 7. You would go to table r503 2 1 1 1 to determine minimum nominal panel thickness. And for wood structural panel sheathing r803 2 2 allowable spans. The typical thickness range for sheathing is 3 8 to 3 4 inch.

Sheathing should be a minimum of 19 32 inch thick. Post frames generally lack structural sheathing so the roof and wall panels must span between the supporting trusses or purlins. 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. Fasteners for asphalt shingles shall be galvanized steel stainless steel aluminum or copper roofing nails minimum 12 gage 0 105 inch 3 mm shank with a minimum 3 8 inch diameter 9 5 mm head complying with astm f1667 of a length to penetrate through the roofing materials and not less than 3 4 inch 19 1 mm into the roof sheathing.

Never attach roof sheathing with staples. Because 22 24 or 26 gauge sheeting is thicker and will therefore remain more structurally sound over a longer span than a 29 gauge the building needs fewer supports which saves your customers money. According to 2009 irc table r803 1 minimum thickness of lumber roof sheathing. 1 inch 25 4 mm.

Roof sheathing comes in grid marked 4 by 8 foot sheets and should be installed perpendicular to the frame.