Both products will swell when wet but plywood will return to almost its exact shape when it dries.
Osb or plywood for shed roof.
University of massachusetts meets most building codes for roof and wall sheathing.
The higher the slope the more quickly the snow and rain will be shed but also the greater the wind force.
Osb is less forgiving of being left out in the rain and will show more deformities after a wetting and drying cycle.
Plywood with similar propertiescurrently costs about 30 more for an equivalent thickness.
As with plywood osb typically comes in 4 ft.
Alternatively osb is created from wood chips resin and adhesive that is baked and formed into the shape of a sheet of plywood.
Using oriented strand board is a tested way of reducing costs for building your shed.
Osb is made of chips of softwood glued together in a semi random pattern.
It is extremely resistant to moisture.
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.
However when it is penetrated by water it takes a very long time to finally dry out compared to cdx plywood.
However there are some sceptics out there who doubt the strength and durability of osb.
Using oriented strand board osb for shed walls floors and roofs.
2x greater shear strength than similar sized plywood source.
Oriented strand board osb is the least expensive option for sheathing the walls and roof of a shed which is why it s used so often for sheds and homes.