Installed R-value vs. Out of Package R-Value
If you look at a duct wrap insulation data sheet, you may notice that there are two different R-Values listed: Installed R-Value and Out-of-Package R-Value. These two R-Values reflect the difference in thermal performance that occurs when you compress the insulation during installation (installed R-value) from the thermal performance of the insulation directly out of the package (out-of-package R-value). The installed R-Values on JM’s duct wrap data sheets reflect the thermal performance of material that has been compressed by 25%, the maximum allowable compression during installation. Anything beyond that hinders the materials’ thermal performance by over-compressing the insulation. The more…