What's Wrong?

[RyanT]

Seams, bending, buckling and corner damage (to which foam core is very, very prone) all make this a less-than-ideal solution. Unless you're after the look of a wall covered with panels of painted foam core.

Yeah, I thought the idea had a few problems myself, but I seem to remember a production designer doing this on a feature I was on a long time ago. I just remember being so surprised when someone told me that the walls were covered in foamcore or something of the sort.

Again, it was over two years ago, so I definitely could be forgetting the specifics.