Osb Sheathing Thickness For Roofs

That in a nutshell is the one big advantage plywood holds over osb.

Osb sheathing thickness for roofs.

Oriented strand board commonly referred to as osb is a type of engineered lumber similar to particle board formed by adding adhesives and then compressing layers of wood strands. When this is the case experts recommend a 5 8 inch thick sheet. 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. A homeowner recently wrote and asked me the following regarding osb roof decking.

The most common rafter spacing is 24 inches and 5 8 inch plywood is recommended for that. The thickness required by josh s circumstances are good for roof snow loads of up to 70 psf again spanning 24. Plywood s advantage over osb. 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. Keep in mind that the load of the roof still plays a role in the plywood thickness. For pricing and availability. It will support roof.

Osb is widely used as roof decking material. Thermostat 7 16 cat ps2 10 osb sheathing application as 4 x 8. For rafters spaced 20 or more inches apart 1 2 or 5 8 inch plywood is recommended. 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.

Panel thickness will also affect permeability using the 2 perm variable of 7 16ths osb sheathing at 3 4 thickness the permeability drops to 2 3rds of a perm. 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. Typical types of wood used for roof sheathing are oriented strand board known as osb and plywood the most popular being osb. For pricing and availability.

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. Using osb osb comes in 4 by 8 foot sheets as does plywood but the manufacturing process allows the production of longer and wider ones. Many homes have rafters that are even wider at 24 inches apart and will require a thicker sheet of plywood.