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Insulation for 400 Square Feet (R-30)

Insulating 400 sq ft with R-30 fiberglass batts takes about 12 bags once you add 10% waste. R-13/R-15 suits 2×4 walls, R-30+ goes in ceilings — set yours below.

Batt bags
12 bags
Area
400 sq ftR-30 batts
Insulation to buy
441 sq ftincludes 10% waste
Batt bags
12 bags~40 sq ft per bag (check label)
Cost (est.)
$484~$1.10/sq ft for R-30
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Other sizes

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