I think some of the differences between this and what Tito did are hard panels vs semi-rigid. When he installed the semi-rigid with the coroplast air gap, he actually attached rails using a kind of 2-sided tape. But that wasn't along the entire rail, it was only on 6-8" at the ends IIRC. Then he used SS hardware to secure the panels to the rails.
With a rigid panel setup, you're talking about 4x brackets per panel? Each bracket only being less than 2" wide? That's A LOT less surface area stuck to the roof than what Tito ended up using. Rightly so, as they're designed to be screwed in. And there's where my concern is. If I'm installing the rigid panels to a rail (as opposed to brackets), I've got PLENTY of surface area to stick that rail to the roof (ignoring and/or accommodating for curvature). I would feel VERY confident sticking that down with VHB, and probably nothing else (but I'm a "belt & suspenders" guy, so I'd probably put something else down; maybe a thick bead of dicor). Then secure the rigid panels to the track/rail with SS hardware.
What I'm wondering is if I decide to use the Z brackets, VHB those to the roof, then cover the entire works with Dicor, would that be enough? I've read where people have used the 5200 that way, and it has worked great for many years of service... I just don't feel like the VHB on the Z-brackets alone would be secure enough for me...
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