Enter the area to insulate and the coverage per package to get how many bags or rolls of insulation to buy.
Coverage per package depends on R-value and thickness — check the label. Subtract large openings; add for framing waste. Estimate only.
Add a waste allowance to the area, then divide by the square footage each package covers. Higher R-value batts are thicker and often cover less area per bag, so use the exact figure on the label.
Packages = ⌈(area × (1 + waste %)) ÷ coverage per package⌉
It depends on climate and where you're insulating (attic vs. wall). Check local code recommendations, then match the batt that hits that R-value.
Batts suit open framing; blown-in fills attics and existing cavities. This estimates batt/roll packages by area.
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