Insulation R-Value Calculator

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Calculate the total R-value and required thickness for building insulation.

Project Details

Insulation Material

Thickness (inches) (in)

Total Area (sq ft) (sq ft)

Insulation Results

Enter specs to estimate insulation value

About this calculator

Overview

Insulation is measured by its R-value, which represents its resistance to heat flow. Higher R-values mean better thermal performance. This calculator helps you determine the total R-value of an insulation layer based on the material type and thickness.

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Pro Tips

When adding new insulation over old, ensure the old insulation isn't wet or moldy.
Seal all air leaks (gaps around pipes, wires, and top plates) before installing insulation for maximum efficiency.
Wear protective gear (gloves, mask, goggles) when handling fiberglass or mineral wool.

Fun Facts

"The Department of Energy recommends different R-values depending on your climate zone (e.g., R-38 to R-60 for attics in cold climates)."
"Compressing insulation (like fiberglass batts) reduces its air pockets and effective R-value."
"Vapor barriers are often required with insulation to prevent moisture from condensing inside the wall cavity."

Formula: R-Value = Thickness (inches) × R-Value per inch