One of the most important, and yet misunderstood aspects of insulation, is R-Value. R-value is a measure of resistance to heat flow through a given thickness and density of material; which ultimately means, the higher the R-value, the greater that resistance. Insulation is measured according to R-value. The higher the insulation R-value determines its effectiveness the amount of energy you will actually save.
The following map is approved by the US Department of Energy represents regions and displays regional R-value insulation recommendations. Depending on the type of insulation material used, it is always best to use a team of expert technicians for the installation.