It's 3"iso 3/4 air space 1/2' osb screwed to metal deck dryin with I&W .Now I'm thinkin it will eazy nailin threw the osb but also ifin the wind was to lift the slate it could pull out the copper nails just as eazy what do you think?
( real slater plezzs dont yell at me :laugh: )>>>
The OSB wood not be my preferred choice but its what I got .I am thinking I'll try my own lift test when get to the end of the project if there is material left over.>>>
Do they make copper toggle bolts? That might be stronger then nails. :laugh:>>>
Ring shank copper nails are much weaker than smooth. Not to mention, an OSB deck is completely unsuitable for a slate roof. Might as well use shingles and the life would be about the same.>>>