Steady envelope conduction calculator

Steady conductive heat rate is calculated as U × A × ΔT. Use the stated system boundary and matching input units.

Units

q = U \times A \times \Delta T

Calculator

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

Given

q = 0.08 \times 2000 \times 40 = 6{,}400

Symbol	Meaning	Unit
$q$	steady conductive heat rate	Btu/h
$U$	overall heat-transfer coefficient	Btu/(h·ft²·°F)
$A$	surface area	ft²
$\Delta T$	inside-outside temperature difference	°F

Symbol	Meaning	Unit
$q$	steady conductive heat rate	kW
$U$	overall heat-transfer coefficient	W/(m²·K)
$A$	surface area	m²
$\Delta T$	inside-outside temperature difference	K

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