๐ Household
Insulation Calculator
Insulation is specified by R-value, a measure of resistance to heat flow. A cold-climate attic targets R-49, a moderate climate R-38, and batts usually come in 15-inch and 23-inch widths to match standard stud and joist spacing.
How it works
Area length
Area width
Target R-value
R-value per inch of material
Waste allowance
Price per square foot
Area to insulate
Insulation thickness needed
Area including waste
Estimated material cost
Frequently asked questions
How do I use the Insulation Calculator?
Fill in the fields above โ the result recalculates instantly as you type. Everything runs in your browser, so the values you enter are never collected or stored.
Is this calculator free?
Yes. It is completely free, requires no account, and works on phones, tablets and desktops.