Net area + product coverage + packages
Insulation Calculator
Estimate whole batt or roll packages, or blown-in insulation bags, using the coverage from the product you plan to buy. Match blown-in coverage to your target R-value.
Example only
- Insulation type
- Blown-in
- Example target
- R-38
- At 0% extra
- 15 whole bags
Your result uses your own inputs, not this example.
Measuring guide
Measure before buying
Measure the area to insulate and subtract openings. For batts, use the package coverage; for blown-in material, use the bag coverage listed at your chosen R-value.
Measure your project
Measure each surface and subtract openings that will not receive insulation.
Read the product label
Match coverage to the material and, for loose-fill, to the target R-value.
Round up to packages
Review the extra allowance, then purchase whole packages for the calculated quantity.
The math
How the quantity is estimated
Net area = measured area − openings. Divide the net area plus your extra allowance by the selected package coverage and round up to whole packages. The calculator does not choose a code-required R-value.
Confirm product coverage and application instructions before ordering.
Reference
Source behind this calculator
Use the label and instructions for the exact product you purchase.
Product coverage
Blown-in bag coverage changes with the target R-value and installed thickness.
Owens Corning AttiCat coverage chart ↗