Insulation Calculator — R-Value & Bags Needed

How the insulation calculator works

Thickness = target R-value ÷ material R per inch. Bag count = area ÷ coverage per bag (bag coverage is printed on the bag at each target R).

US DOE recommends R-38 to R-60 depending on climate zone. Most cold climates target R-49 or higher.

Blown-in fills irregular spaces and adds R fast in attics. Batts are simpler for open stud/joist bays.

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