How Thick Should Osb For Roof

Most roofs will be sheathed in plywood at least 3 8 inch thick.

How thick should osb for roof. Several factors must be considered when determining appropriate roof sheathing thickness such as the. Required sheathing thickness for roofing important factors. Roof sheathing standard roof sheathing which consists of 4 by 8 sheets of plywood or oriented strand board or osb is 1 2 inch thick and attaches directly to the roof rafters or the roof trusses. Watch this now to learn how to avoid this same pr.

You need to find a sheathing with a span rating of at least 32 16 which means either 15 32 or 1 2 thick osb. That will suffice on a roof with rafters set 16 inches apart with minimal roof loads. Loads will vary with the pitch of the roof. Osb roof decking thickness 7 16 1 2 or 5 8 currently we space rafters 16 oc and use 7 16 osb with h clips.

With this thickness any deflection under dead loads only the weight of materials only should prove to be imperceptible. Half inch osb is suitable for rafter spacings up to 24 inches whether or not the edges are. An exception to this standard however may occur if you intend to install slate concrete or tile shingles on your roof. 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.

We re in dallas so we don t engineer for tremendous live loads for an asphalt shingle and we feel comfortable with 16 oc rafter spacing and 7 16 osb decking. Thicknesses range from 5 16 to 3 4 inch and the proper one to use depends on the spacing of the rafters. Typical types of wood used for roof sheathing are oriented strand board known as osb and plywood.