We have a 1/2 story that was cheaply finished prior to us moving in. Looking into it, it looks like we have 4-5" of fiberglass bat insulation in the ceiling which is, if we're lucky, something like r-12. Certainly not ideal for our 90 degree summers and -10 degree winters here in MN.
Since the place has to be remodeled anyways, I'm toying with the idea of ripping down all the sheetrock, then putting up 1 or 2" XPS, then re-sheetrocking. That should give us an extra 5 or 10 in r-value. Still not ideal, but better.
I've been doing more research on PIR panels. These appear to be better than XPS in the r-value department with a value of 7 per inch.
I then came across this product:
http://www.bombayharbor.com/Product/24725/Pur_Or_Pir_Sandwich_Panels_P_Vd_Ribbed_Surfaced.html

Anyone know where to source this in the US? Or similar products? I like the idea of an insulated panel that has a finished exterior already. It's a) taking up less space (more room for insulation) and b) seems great for a lazy person like me.
Obviously, this example was designed for exteriors, but I do like the industrial corrugated metal look and would consider it for interior use. Alternatively, anyone know of similar type products?