I think I made have made a big mistake on my basement subfloor.    The stack-up is Delta-FL, followed by high compressive strength XPS foam (60 psi vs. the normal 20 psi), then 7/16 OSB.  The plan is to stagger the joints on each layer than tapcon the whole thing down to the slab.

I bought the 7/16″ OSB because we were concerned about cost and ceiling height and this was the minimum size recommended by Dorkin for the Delta-FL.   Also, the 7/16 was only available without tongue and grooves.   From reading further now, I see that most people use tongue and groove and at least 5/8″ OSB, more commonly even 3/4″.

Am I going to have problems with just 7/16″?  If so, what would the suggested fix be?

Thanks in advance,

Patrick