OpenTools

Construction tools

Insulation Calculator

Estimate net insulation coverage and whole packages using coverage from the product label.

Insulation coverage estimate

Use the coverage printed on the selected package. Choose R-value and assembly requirements separately for your location.

Surface

Coverage, not R-value selection

The material estimate uses surface area − openings and round up(order area ÷ package coverage).

R-value depends on insulation type and thickness, while requirements vary by climate zone, assembly, and adopted energy code. This calculator intentionally leaves that decision outside the arithmetic.

Insulation calculator FAQ

Does this select an R-value?
No. R-value depends on insulation type and thickness, while requirements vary by climate zone, assembly, and adopted energy code. The calculator intentionally leaves that decision outside the arithmetic.
Does it model framing or thermal bridging?
No. It estimates one rectangular surface and does not model framing, cavity count, compression, thermal bridging, air sealing, moisture control, or installation quality.
Where does package coverage come from?
Use package coverage for the exact R-value and product configuration selected. Confirm code, fire, vapor, ventilation, and safety requirements with the authority having jurisdiction and the manufacturer.

Method & sources

Whole packages are rounded up only after openings and the visible allowance are applied.

Important limits

  • This estimates one rectangular surface and does not model framing, cavity count, compression, thermal bridging, air sealing, moisture control, or installation quality.
  • Use package coverage for the exact R-value and product configuration selected.
  • Confirm code, fire, vapor, ventilation, and safety requirements with the authority and manufacturer.

Reviewed references