RVM

I'm thinking of switching from Celotex (I really don't like this stuff) to Owens Corning Foamular for my building surface. My question is this: how dense does the Foamular need to be? I can get the Dow blue stuff at Lowe's, but it isn't that dense. Foamular 150 is about the same density as the blue stuff. I was wanting to go with at least Foamular 250, as I feel the denser the better, because it will hold pins tighter and will also more effectively resist deformation if you are applying weight. I see that you can get up to Foamular 1000, which can handle 100 PSI and is the most dense version available. Would that be too dense?

Anyway, just wondering if anyone had experience with Foamular and which one has proven best for a building surface, assuming it has proven useful at all. A search only revealed information on using it to build foamies.

Thanks!