DanG wrote:
Pat, it is sad when people answer that don't know what they are
talking about. The OSB is plenty strong enough, ...

But OSB bending moment is only about half that of Doug fir ply from data
from Canadian plywood association.

Whether it's "stiff enough" depends on how well braced and how much a
pour, neither of which was provided. There's no doubt at all it'll take
more bracing to maintain the same form straightness w/ OSB as compared
to ply.

If you don't believe it, look up the bending moments data yourself...

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