Common Types of Plywood: Not all used for crate construction


Plywood is actually composed of several layers of wood glued together. Plywood is commonly composed of 3 or 5 layers.



nted strand board (OSB) is composed of wood strands or flakes compressed with glue. 


Medium density fiberboard (MDF) is composed of small wood fibers compressed with glue. The smaller fibers offer neat edges and a smooth surface. MDF is commonly used in cabinetry.

Particle Board 

Particle Board is composed of small wood particles compressed with glue. The particles are bigger than the fibers used in MDF but smaller than the flakes used in OSB. Particle board is often used for floor sheathing, shelving, and furniture.

Block Board 

Block board is a panel composed of boards glued edge to edge and then sandwiched between sheets of veneer. It is very strong and rigid and is more often used in furniture.

What is CDX?

CDX is veneer plywood, which is manufactured by gluing and pressing together sheets of wood. The letters C and D represent the grades of either side of the plywood, while X stands for exposure.

What is OSB

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.

Major differences between OSB and CDX

Resistance to water

As mentioned above, the X in CDX stands for exposure. This means that the plywood allows being exposed to moisture, but just for a limited period of time A prolonged exposure will lead to water damage. But, there is an exception to pressure-treated CDX; they can withstand extreme moisture without getting water damaged.

OSB holds up to water quite well, and it is easily seen as water-proof. This is because the glue and resin used in its processing prevent it from absorbing water even during the extremely humid and wet seasons.

Dimensional stability

Even though CDX is not waterproof and absorbs water easily, it also loses this water quickly and goes back to its original shape. This makes its dimensional stability better

However, OSB does not absorb water easily, but when it does, it takes quite a while to lose the water. Even after losing the water, it will take time for it to go back to its original state.