PUR is typically 5-7.1 per inch, while PIR is typically in the 7-7.2 per inch range. The insulation re with one of the highest R-values is QuadCore, with an R-value of 8.0 per inch. Because of this, most insulated metal panels have an R-value of R-5 to R-64, with panels ranging from 1 inch thick to 8 inches thick.