Slab-on-Grade Insulation Calculator

Estimate slab-on-grade perimeter heat loss with the ASHRAE F-factor method, compare insulation strategies, and see annual heating cost and payback vs an uninsulated baseline.

Default slab example

  • 180 lin ft perimeter, ΔT 70°F, 5,000 HDD
  • Uninsulated baseline (F-0.73): $822/yr heating cost
  • R-10 vertical 24" edge (F-0.52): $585/yr — saves $237/yr
  • Frost-protected shallow (F-0.38): $428/yr — best long-term performer

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