Improving Attic Insulation

With the many benefits of having adequate insulation in your attic, it comes as no surprise that recent research shows adding insulation is the #1 way to increase the value of your home. Benefits include:

      • Saving Money: Save up to 20% on your home’s heating and cooling bills
      • Year-Round Comfort: Make your environment warmer in winter and cooler in summer
      • Reduced Noise: Reduce room-to-room sound transmission
      • Boosted Resale Value: Adding insulation is the only home improvement project that pays back more money than spent

Follow the steps below to improve your attic insulation.

1. Identify the Desired R-Value

For guidance on the ideal R-value for your home, please refer to the energy code map. To learn more about the best insulation type for your project, consult with your local building official or home inspector. Keep in mind that batts should never be installed over blown-in insulation.

Climate Zone Map

Add Insulation to Attic


2. Calculate the Existing R-Value

When improving your home’s attic insulation, first calculate the existing R-value. You will then determine how much insulation should be added to achieve the desired R-value. 

The simplest way to determine your existing R-value is to read the attic installation card or insulation certificate. If these are not available, there are other options to assess R-value. For faced insulation, the R-value will generally be printed on the facing. For unfaced insulation, loose fill or cellulose, please use the following calculations. R-value will vary depending upon the density of the product, and these are the minimum R-values per inch for the insulation types:

      • For loose fill, such as EcoFill, multiply the depth by a minimum of R-2.67 per inch
      • For batts, such as EcoBatt, multiply the depth by a minimum of R-3 per inch
      • For cellulose, multiply the depth by a minimum of R-3.4 per inch (please note cellulose is not a Knauf product)


3. Calculate the Additional Insulation Needed

Subtract the R-value you currently have from the R-value you want to achieve to determine the additional R-value needed.