flanajb":1lo5pcu6 said:
You just need to make sure what ever adhesive you use does not contain styrene.
Or acetone, or xylene, or any one of many other solvents which styrene will dissolve in. And that it doesn't get hot while it cures, because polystyrene melts at fairly low temperatures and IIRC gives off toxic fumes.
To be honest, if I were in the same situation and I had some to hand, I'd probably try one of the various no-more-nails-a-likes on a scrap of the insulation board, leave it to dry to see if it damaged it - I'd expect it to be absolutely fine. As a last resort, you'd probably have success with heavy-duty double-sided tape, but it's probably an expensive way to do it.
I seem to recall polystyrene breaks down under UV, and can crumble away after a couple of years if it's not covered, so it's probably worth putting boards or paint over it once it's hung. (If you do paint it, again, be careful which paint you use - water-based is generally best.)
I'm possibly over-thinking it, but if you're planning to attach some kind of hard surface to the inside after the insulation anyway, could you not just sandwich the polystyrene in and fasten those mechanically? Attach battens to the wall, stuff the insulation between the battens and then screw boards to the battens over the top, or something? Whatever adhesive you use, the polystyrene will break well before the glue fails - I don't know what the standard practice is, but I wouldn't trust it to hang boards on or anything myself...
