Conductance and overall U calculator

Conductance is the reciprocal of resistance; conductances of series layers are not added.

Units

U_{\text{total}} = \frac{1}{R_{\text{total}}}

Calculator

Enter the values you know and leave one box empty. Calculate finds the empty one, the result or any input.

Given

U_{\text{total}} = \frac{1}{18} \approx 0.0556

Symbol	Meaning	Unit
$U_{\text{total}}$	overall conductance	Btu/(h·ft²·°F)
$R_{\text{total}}$	total resistance	h·ft²·°F/Btu

Symbol	Meaning	Unit
$U_{\text{total}}$	overall conductance	W/(m²·K)
$R_{\text{total}}$	total resistance	m²·K/W

Results are estimates for study and screening. Check the inputs, units and assumptions before you use them for design, billing or contract decisions.