How Thick Should Osb Be For Roofing

Osb comes in 4 by 8 foot sheets as does plywood but the manufacturing process allows the production of longer and wider ones.

How thick should osb be for roofing. Plywood is a bit more expensive but is usually stronger and is often selected in cases where the roof covering is heavier such as for slate clay or concrete tile roofs. 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. Sheets of 7 16 inch thick with no edge support can be used in an area where the snow load is 30 pounds per square foot. Typical types of wood used for roof sheathing are oriented strand board known as osb and plywood the most popular being osb.

Osb roof decking thickness 7 16 1 2 or 5 8. 8 tips for getting the best out of your oriented strand board osb how to install roof sheathing pro builder. Roofing plywood sizes material wood joist and plywood or osb decking oriented strand board common 15 32 in roof decking material thickness osb or plywood for roofs walls roof deck materials to ensure a le. With edge support and the same snow load 3 8 inch osb can be used.

Osb is lightweight relatively inexpensive and strong enough to resist bending or breaking should someone walk on the roof. 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. 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. 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.

Thicknesses range from 5 16 to 3 4 inch and the proper one to use. An exception to this standard however may occur if you intend to install slate concrete or tile shingles on your roof. With this thickness any deflection under dead loads only the weight of materials only should prove to be imperceptible. Currently we space rafters 16 oc and use 7 16 osb with h clips.