Blown In Insulation Calculator

How much blown in attic insulation do I need?

This calculator should be used as an estimating tool ONLY.

To determine the number of bags of blown in insulation needed:

1. Measure the depth of your existing insulation and enter this number below.
2. Is your current insulation fiberglass (applied in rolls / batts) or cellulose (loose, sprayed-in material)?
3. Based on your desired R-value, how many total inches of insulation do you need? (See map for regional recommendations.)
4. Enter the dimensions of your attic.

• 1
  • Measure the depth of your existing insulation and enter this number below.

    Current Depth: in.
  • Current Insulation Type:

    Fiberglass Cellulose
    

    NOTE: Fiberglass insulation can be installed in rolls (called batts) or blown in. Cellulose is loose, blown in material.

  Next Step: Your Desired R-value
• 2
  • Determine Your Desired R-value.

    Estimated Current R Value:

    Your Desired R Value:

    
    

    See the map below for recommendations for your zone.

    Recommended R-value Range for an Uninsulated Attic
    Zone R-value Range 1 R30-R49 2 R30-R60 3 R30-R60 4 R38-R60 Zone R-value Range 5 R49-R60 6 R49-R60 7 R49-R60 8 R49-R60

  Back | Next Step: Measure
• 3
  • Enter the dimensions of your attic.

    • Width: ft.
    • Length: ft.
  • Desired Insulation Type:

    Fiberglass Cellulose
    

    NOTE: Fiberglass insulation can be installed in rolls (called batts) or blown-in. Cellulose is loose, blown-in material. Adding rolled insulation on top of existing blown-in insulation is not recommended.

  Back | Next Step: Results