Calculate conductive heat flow through a material using Fourier’s law.
Conductive heat flow is inversely proportional to thickness, so doubling insulation thickness halves the conductive loss. Thermal resistance is thickness divided by conductivity. Because the relationship is inverse rather than linear in reduction, the first 50 mm of insulation saves far more than the second 50 mm.
Conduction Heat Transfer
Q̇ = k A ΔT ÷ L (Fourier’s law)
Q̇ = k A ΔT ÷ L (Fourier’s law) Conductive heat flow is inversely proportional to thickness, so doubling insulation thickness halves the conductive loss. Thermal resistance is thickness divided by conductivity.
Because the relationship is inverse rather than linear in reduction, the first 50 mm of insulation saves far more than the second 50 mm.
This calculator takes 4 inputs: Thermal conductivity, Cross-sectional area, Material thickness, Temperature difference. The pre-filled defaults are a realistic starting point — replace them with figures from your own environment for a result you can act on.