Exactly how much Insulation should I put in my attic?

R-Value is a term used to describe the insulation level. In insulation, R-Value refers to the material’s capacity to resist heat flow. Higher R-Value insulation has superior thermal performance. Depending on the kind of insulation, it is advised to insulate most attics to an R-38 rating, which equates to 10 to 14 inches of insulation.