Use this free insulation calculator to estimate pack count, total coverage, and optional cost from area, openings, coverage per pack, and waste.
880 net ft2 at 40 ft2 per pack
R-value, vapor control, air sealing, ventilation, moisture, fire rules, and local code matter. Match the product to the project, not just the square footage.
Estimate insulation packs for walls, attics, or floor areas.
Subtract doors, windows, and hatches before waste.
Use product-label coverage per package.
Estimate rough cost from price per pack.
25 packs
Pack count estimate
Insulation packs
Plain-language answers about when to use the tool, what it does with your inputs, what to double-check, and how privacy works.
Use it when your task matches one of these common needs: Estimate insulation packs for walls, attics, or floor areas. Subtract doors, windows, and hatches before waste. It works best when you already know the values, dates, units, or settings the page asks for.
In plain language: The calculator subtracts openings from measured area, adds waste, divides by square feet covered per pack, and rounds up to whole packs. The examples on the page are there so you can compare your inputs with a filled-out calculation before copying the answer.
Area: the wall, ceiling, floor, or attic square footage before subtracting openings. Openings: windows, doors, attic hatches, or other spaces that should not receive insulation. Coverage per pack: the square feet one package covers at the product thickness or R-value. Waste percent: extra insulation for cuts, odd cavities, fitting, and mistakes.
Read the headline estimate first, then check the material, waste, coverage, and unit lines. For project tools, the supporting lines are often the difference between a rough idea and a list you can actually shop from.
Insulation is not just area. R-value, climate zone, air sealing, vapor control, moisture, ventilation, fire rules, and local code all matter. Also check that you used the right unit, date, scale, or mode because small input changes can change the result.
R-value is resistance to heat flow. Higher R-value usually slows heat movement more, but the right target depends on the location, climate, product type, and code.
No. It estimates packs after you choose a product. Use local code, ENERGY STAR or DOE guidance, and product labels to choose the right R-value and installation method.
No. The calculator runs in your browser tab. Your recent answers stay only on the page while you use it, and they are not sent to a server.