2mm aluminium treadplate on 200mm/8 inch centres?

I've just sent him an email to this effect. Dab-off is a Wurth product so it won't be cheap I wouldn't have thought - but its certainly not a marine adhesive either.

 

Rivets will be the primary bond, the adhesive will be secondary, and only comes into play when the rivets fail.

The elongation on something like 5200 is far greater than a rivet.

The silicone he plans to use may only be to prevent the floor from vibrating and rattling.

The last aluminum floor we put in was secured with Velcro tape. It held up great for the several years it was used as a commercial guide boat. Easy to install, easy to pull up.

 

3M makes some incredibly strong double sided tapes.
They might be more practical to use, as compared to cleanly and evenly applying the correct amount of caulking to the considerable footage to be covered.
I use the stuff to fasten windows in place, with very good results.
My test panels, acrylic sheet taped to fiberglassed plywood, consistently separated the plywood below the resin penetration.

 

not a fan of the idea..I have used them and they are not as good as in the tube sealants

where they shine is if you want a flat joint or if you simply don't have open time for a glue bead