Fiberglass Batt Insulation Calculator

Fiberglass batt is the low-cost baseline for many DIY insulation projects, but it depends heavily on good air sealing and careful installation. Use this as early material planning only; confirm actual product datasheets and local assembly requirements.

Default material estimate

  • R-value per inch: R-3.4
  • Required thickness for R-20: 5.9 inches
  • Order area with 10% waste: 550 sq ft
  • Estimated material cost: $748

Material snapshot

  • Category: Batt
  • Form: Pre-cut cavity batts
  • Typical use: Budget wall, floor, and attic cavities where air sealing is handled separately.

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