Minimum Sheathing Thickness Roof

Post frames generally lack structural sheathing so the roof and wall panels must span between the supporting trusses or purlins.

Minimum sheathing thickness roof.

The thickness of plywood used for roof decking depends on the roof slope the spacing of rafters and the weight of other material to be put over the decking as well as the design load the. 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. You would go to table r503 2 1 1 1 to determine minimum nominal panel thickness. 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.

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. 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. 1 inch 25 4 mm.

8d ring shank nails should be used instead. Roof sheathing comes in grid marked 4 by 8 foot sheets and should be installed perpendicular to the frame. 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. Floor or roof sheathing conforming with this table shall be deemed to meet the design criteria of section 2304 7.

According to 2009 irc table r803 1 minimum thickness of lumber roof sheathing. Sheathing should be a minimum of 19 32 inch thick. This way no worrying about grabbing scraps to fill in small spots and not having the correct thickness. Never attach roof sheathing with staples.

Many code requirements are not inspected.