Osb Vs Cdx Plywood For Roof

Osb is a cheap imitation of cdx.

Osb vs cdx plywood for roof.

Osb and plywood offer similar and sufficient performance in terms of strength and functionality though plywood is about 7 stronger the main difference between the two is how they handle moisture and oddly enough there are wildly varying conclusions from very reputable sources as to just how vapour permeable they are. Osb does not provide adequate protection against fast moving storm debris. Far too often i see osb sag between the trusses making your roof look wavy. Over the years i have seen claims for plywood decking delaminating which can cause squeeks and knocks between the ply s.

Going back to the x in cdx you may recall that it means exposure. Although osb typically offers a higher shear rating which adds rigidity to your structure. When you are boarding up for a big storm you should be using at minimum 1 2 cdx plywood. Osb does not do well when it gets wet.

However you might find that osb can better suit your needs than plywood for the roof. It is usually made of 4 by 8 sheets that should be 1 2 thick. Oriented strand board osb combines wood chips glue and resin into the shape of a sheet of plywood and bakes them together. Now let s have a look at some of the main differences between cdx and osb as roofing plywood.

It is made of multiple layers of thinly cut solid sheets of wood that are pressed together. How do cdx and osb differ in performance. The result is a wooden sheet that is. One of the major differences between osb and cdx plywood is how well each holds up against water.

Differences between osb and cdx for roofing plywood. Both cdx plywood and osb tend to come in standard sheets of four foot by eight foot 4 8. It is often less expensive than cdx plywood because this manufacturing process doesn t require the same costly veneers found on the front and back of cdx plywood. Osb on the other hand stands for oriented strand board which is a cheaper version of cdx.

It is made of wood chips resin and glue cast and baked together to produce a cdx like sheet. The letters c and d represent the grades of either side of the plywood while x stands for exposure. This means that osd is the perfect choice for applications such as exterior wall sheathing and roofing. My go to option for cabinets boxes and work tables surfaces is 3 4 birch plywood.

My personal opinion is that osb performs well on the wall and floor but stick to cdx plywood on the roof. It is made of wood chips and glue. Although osb typically offers a higher shear rating which adds rigidity to your structure. Cdx plywood is produced by gluing together sheets of veneer with each layer being glued the opposite grain to the one below it.

Because of its construction some manufacturers actually make larger sheets of osb. My personal opinion is that osb performs well on the wall and floor but stick to cdx plywood on the roof. Cdx is veneer plywood.