An R-Value is a measure of the resistance to heat transfer of a given material. A larger R-Value number means it takes longer for the same amount of heat to move through a substance. The effectiveness of insulation’s resistance to heat flow depends on how and where the insulation is installed. The amount of insulation or R-value you’ll need depends on your climate, type of heating and cooling system, and the section of the house you plan to insulate. Have an expert help you determine what R-Value you need!