Closed-Cell Spray Foam Insulation Calculator

Closed-cell spray foam provides high R-value in limited space, but it deserves careful detailing because it changes drying behavior. Use this as early material planning only; confirm actual product datasheets and local assembly requirements.

Default material estimate

  • R-value per inch: R-6.5
  • Required thickness for R-20: 3.1 inches
  • Order area with 10% waste: 550 sq ft
  • Estimated material cost: $1,964

Material snapshot

  • Category: Spray foam
  • Form: Site-applied high-density foam
  • Typical use: Thin cavities, rim joists, metal buildings, and assemblies needing air and vapor control.

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