Osb Sheathing Thickness For Roofs

A flatter roof with rafters farther apart may need a thickness of up to inch.

Osb sheathing thickness for roofs.

With edge support and the same snow load 3 8 inch osb can be used. When this is the case experts recommend a 5 8 inch thick sheet. Typical types of wood used for roof sheathing are oriented strand board known as osb and plywood the most popular being osb. 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.

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. It will support roof. 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. 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.

Thicknesses range from 5 16 to 3 4 inch and the proper one. For pricing and availability. 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.

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. 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. The thickness required by josh s circumstances are good for roof snow loads of up to 70 psf again spanning 24. Keep in mind that the load of the roof still plays a role in the plywood thickness.

Plywood s advantage over osb. Osb is widely used as roof decking material. That in a nutshell is the one big advantage plywood holds over osb. For rafters spaced 20 or more inches apart 1 2 or 5 8 inch plywood is recommended.

Thermostat 7 16 cat ps2 10 osb sheathing application as 4 x 8. The most common rafter spacing is 24 inches and 5 8 inch plywood is recommended for that. A homeowner recently wrote and asked me the following regarding osb roof decking.