When most people refer to floating floors in the skoolie context, they mean floating the subfloor itself... rigid sheet insulation directly on the steel floor, then (usually) plywood over that. All without any framing/studs/sleepers. Is this what you're talking about? Or are you saying you'll be floating your finished floor material later over a more traditional stud/sleeper floor you're installing now?
Regardless, shiny products advertised as thermal barriers don't do a lick of good when placed directly against any surface, including your steel floor. Real insulation is, by definition, a thermal barrier. Don't waste space with stuff like this when you could add more of it instead.
Go away. 'Baitin.
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