What is Insulation Calculator?

Insulation Calculator helps you determine the right amount of insulation for walls, attics, and floors. Enter your climate zone, area dimensions, and desired R-value to get precise material quantity estimates, helping you save on energy costs and meet building codes.

How to use

1. Step 1 — Select the area type (wall, attic, floor, or basement) and enter the dimensions (length and width or total area in square feet or meters).
2. Step 2 — Choose your target R-value based on your climate zone, or use the recommended values provided for common regions.
3. Step 3 — View the calculated insulation thickness needed for different materials (fiberglass batts, blown-in cellulose, spray foam) and download the estimate.

Result

You're insulating a 1,200 sq ft attic in a cold climate (Zone 5). Set the area to 1200 sq ft, target R-49, and see that you need approximately 16 inches of blown-in fiberglass or 13 inches of cellulose.

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