Blown-In Fiberglass Insulation Calculator

Blown-in fiberglass is a practical attic top-up material when you need fast coverage over a large open area. Use this as early material planning only; confirm actual product datasheets and local assembly requirements.

Default material estimate

  • R-value per inch: R-2.8
  • Required thickness for R-20: 7.1 inches
  • Order area with 10% waste: 550 sq ft
  • Estimated material cost: $781

Material snapshot

  • Category: Blown-in
  • Form: Loose-fill fiberglass
  • Typical use: Open attics and accessible horizontal cavities.

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