Osb Vs Plywood For Shed Roof

Secondly osb panels have a higher shear rating than plywood panels and are thus often installed with greater spans than plywood of the same thickness.

Osb vs plywood for shed roof.

Because of this manufacturing process osb is at least half the cost of cdx plywood. Oriented strand board isn t plywood nor is it a type of particleboard fiberboard or wafer board and although it is a newcomer to a plywood dominated market its use for exterior sheathing is. Plywood is better than osb for subfloors. Building codes the engineered wood association architects and most builders rate plywood and oriented strand board obs sheathing equal in strength and durability.

Osb is made by combining glue resin and wood chips and pressing them into the shape of a plywood sheet then baking everything together. Osb is now used for about 70 percent of all floor wall and roof sheathing in north america. The lower the slope the more weight for snow load but less wind force. In 2001 oriented strand board surpassed plywood in terms of square footage produced.

New homes will usually see a few rainfalls before a roof is on and as noted above osb doesn t handle moisture well. While a sheet of plywood might be 5 to 7 plies thick a sheet of osb is made from as many as 50 strand layers packed and compressed into the same thickness. Because of its construction some manufacturers actually make larger sheets of osb. Both cdx plywood and osb tend to come in standard sheets of four foot by eight foot 4 8.

2x greater shear strength than similar sized plywood source. Even though plywood is more expensive and osb stronger my recommendation for a shed roof is 5 8 or 3 4 construction grade exterior rated cdx t g plywood. This can result in visible deflection of the panels between the supports and can telegraph through causing a wavy appearance to the roof. Compared to cdx oriented strand board osb is made very differently.

Osb boasts a more consistent density. Today you can find osb in thickness from 7 16 to 1 1 8 for different applications from roof wall subfloor i joists and everything between. University of massachusetts meets most building codes for roof and wall sheathing. Despite its common use as such we don t recommend using osb for subfloors but that s really just for aesthetic reasons.