Original sentence: Ask for the R-value tests from the manufactur for your for your specific assembly.Insulated Concrete Form (ICF) Is rated at R-20.R-2  (may be near zero in assembly without airspace)
Edited sentence: Ask for the R-value tests from the manufactur for your specific assembly.Insulated Concrete Form (ICF) is rated at R-20.R-1 >Link text, FTC Letter - Regarding reflective insulation used under slab where no air space is present  (For assembly without adjacent air space