Once you find your zone on the map, you can then use the R-value insulation chart below to determine the ... has the higher average R-value per inch. If you aren’t sure which insulation material ...

But, this is where it gets complicated: The assigned insulation R-value represents how much heat resistance the material has per inch of depth. That means a lower R-value material could provide a ...

Included in the HTML version of this fact sheet is a handy calculator called Zip-Code, which gives the recommended R-value for insulation — and the estimated cost of installation — depending ...