Most of the time there is very little harm and the material doesn't loose strength or any of its integrity. Under the best circumstances, the OSB sheathing is delivered to the site, installed and covered within a few days. OSB that does get wet will tend to swell and delaminate first at the edges of the boards.
Similarly, it is asked, which side of OSB goes down?
A wall, a floor, or a roof will be just as strong no matter which side faces up or out. But on a newly sheathed roof, leaving the lightly textured side up does give a bit of extra traction. If the OSB has tongue-and-groove edges, there's another issue to consider.
Is OSB as strong as plywood?
Wood fiber is used more efficiently in osb. Osb is stronger than plywood in shear. Shear values, through its thickness, are about 2 times greater than plywood.This is one of the reasons osb is used for webs of wooden I-joists. However, nail-holding ability controls performance in shear wall applications.
What is an OSB board?
Oriented strand board (OSB), also known as flakeboard, sterling board and aspenite in British English, is a type of engineered wood similar to particle board, formed by adding adhesives and then compressing layers of wood strands (flakes) in specific orientations.