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Insulation for 300 Square Feet (R-30)

Insulating 300 sq ft with R-30 fiberglass batts takes about 8 bags once you add 10% waste. R-13/R-15 suits 2×4 walls, R-30+ goes in ceilings — set yours below.

Batt bags
8 bags
Area
289 sq ftR-30 batts
Insulation to buy
318 sq ftincludes 10% waste
Batt bags
8 bags~40 sq ft per bag (check label)
Cost (est.)
$350~$1.10/sq ft for R-30
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Want the full guide — tools, step-by-step, common mistakes and FAQ? See the Insulation Calculator.

Other sizes

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