The amount of insulation a house needs is dependent on its location. The amount of insulation a home needs is expressed in its R-value or insulating power. A home in the Tallahassee area needs much less insulating power than a home in Minnesota or Maine. Different types of insulation have different levels of R-value. For attic insulation, a Tallahassee home should have an R-value of 30 to 60 for an uninsulated attic, or R25 to R38 for an attic with existing insulation. These recommended R-values can change.