I wonder if anybody has ever considered or tested using corrugated steel as a SIP skin for high-strength applications.  Seems to me it would add considerable strength to the panel, which would be particularly useful for roof and floor applications.  As the outside skin for a roof or wall, you might even be able to get away without any additional finishing (other than flashing over seams), if you're OK with an industrial look.  As a floor panel, I think it would make sense to do corrugated steel on the bottom skin and OSB on the top skin, unless you want to pour concrete over it when you're done, in which case corrugated steel would make a lot of sense as the top skin.

Am I crazy, stupid, or both?

mortman;

its already being done by several PU mfgs. unfortunately their span capabilities are much less than other EPS/steel & OSB panels

the attachment shows profile

Steel Companies are now getting on board to produce some very interesting panel systems.

KORETECK is a Steel Company that produces a unit that uses Steel embedded with the EPS Core
and will then receive any surface finish you require