My personal opinion is that osb performs well on the wall and floor but stick to cdx plywood on the roof.
Osb vs cdx roof sheathing.
One of the nice things about plywood is the variety of options you can buy.
Up until 2000 plywood held the majority of the market for wall roof and floor sheathing when it was surpassed by osb which as of 2018 held about 75 of the market share.
It is also used for roof sheathing.
In such places it does not get in contact with a lot of moisture which prevents it from getting damaged.
Osb is made by combining glue resin and wood chips and pressing them into the shape of a plywood sheet then baking everything together.
2 perm 7 16 osb sheathing with a 5 perm wrb results in 1 43 perms.
That may not seem like a lot but when you are that close to the danger zone a 24 difference in permeability between final products is worthy of note.
Cdx and osb are used for almost similar things but because they have different features one is better applied in some tasks and the other one on other tasks.
Osb is also known for swelling along the edges when it gets wet which can cause an uneven subfloor and ghost lines on an asphalt roof shingles.
Although osb typically offers a higher shear rating which adds rigidity to your structure.
Wall sheathing and roofing.
Each layer is placed on top of the other with the graining running in the opposite direction for the opposing layer.
The major distinction between these categories is the actual construction of the sheets.
We have used osb for some time now we use 5 8 on the roof 7 16 on the sidewalls all with plywood clips for strength and proper exspansion gaps however 3 4 t g ulc or cdx for floors stands up to the weather while building.
Cdx plywood is created by bundling layers of wood together.
Because of this manufacturing process osb is at least half the cost of cdx plywood.
Compared to cdx oriented strand board osb is made very differently.
Cdx is best for sub flooring.
Before you can really grasp the different ways to use cdx plywood vs.
Far too often i see osb sag between the trusses making your roof look wavy.
Osb it can help to have a better understanding of what each of them is.
Though manufacturer s claim they now coat the edges in water resistant seals to prevent this because boards are commonly cut to fit the structure there are still exposed edges.
The result is a wooden sheet that is proportionally as strong as steel without the weight that comes along with concrete or steel.
