Garage Roof Sheathing Thickness

Minimum thickness most roofs will be sheathed in plywood at least 3 8 inch thick.

Garage roof sheathing thickness. If your roof is more on the flatter side then it s expected to have a heavier load. Roof sheathing or decking is one of those elements. If the nails penetrate the sheathing but not the studs the minimum plywood thickness that the irc designates is 1 2 inch. That will suffice on a roof with rafters set 16 inches apart with minimal roof loads.

For heavier loads a 40 20 rated panel 19 32 or 5 8 will support a 130 psf live load and 48 24 rated panels 23 32 or are good to175 psf. Roof sheathing comes in grid marked 4 by 8 foot sheets and should be installed perpendicular to the frame. The inch thick boards extend from the eaves just past the exterior walls where they butt up against the plywood roof sheathing. That s considered to be the minimum.

When ordering the sheathing divide the total number of square feet of roof surface by 32 square feet a 4 x 8 panel and add an extra 15 for waste. This minimum will only work if the rafters are set 16 inches apart at most and if the roof doesn t have too much load. Never attach roof sheathing with staples. Get free estimates from local roofing contractors.

Unlike with plywood siding the plywood sheet to be used for sheathing should be at least 3 8 inch thick. For the curious 7 16 osb has a span rating of 24 16 and with supports every 24 inches is good for a roof live load of 40 psf pounds per square foot with a 10 psf dead load. In practice many builders default to 1 2 inch plywood even if they plan. The thickness will range from 3 8 to 3 4 inch depending upon local code.

In the u s roof sheathing is almost always composed of wood usually osb oriented strand board or plywood. Roof trusses when used shall be engineered and pre manufactured. Roof material then covers all. 7 16 plywood or similar with span rating of 24 0 supported on 24 centers requires h clips on all horizontal joints centered in each rafter bay.

Loads will vary with the. The typical thickness range for sheathing is 3 8 to 3 4 inch. Osb is lightweight relatively inexpensive and strong enough to resist bending or breaking should someone walk on the roof. The thickness required by josh s circumstances are good for roof snow loads of up to 70 psf again spanning 24.