HVAC & Refrigeration

Basic

Thermal Resistance (R-value)

Insulating power of a material layer of given thickness.

Formula

R = \frac{L}{k}

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Variables

RThermal resistance (m²K/W)

LThickness (m)

kConductivity (W/mK)

Example

L=0.1 m, k=0.04: R = 2.5

Did You Know?

Doubling insulation thickness doubles the R-value but yields diminishing comfort returns.

hvac insulation rvalue

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