Building Envelope Heat Loss & Thermal U-Value HVAC Calculator
Calculate conductive heat loss through walls and windows (Watts, kW, BTU/hr) using thermal transmittance U-values and indoor/outdoor design temperature differences.
Calculator Inputs
Live Real-TimeTotal Heating Demand (kW)
Heating Capacity (BTU/hr)
6,568.37 BTU/hr
Wall Heat Transmission (Watts)
1,050 W
Window Heat Transmission (Watts)
875 W
HVAC Thermal Sizing: Provides exact thermal capacity baselines for building heating systems.
Heat Loss Distribution
Detailed Calculation Breakdown
Calculation Methodology
Heat Loss: Q = U * A * ΔT. Total Heating Load (kW) = (Q_walls + Q_windows) / 1000. Heating Capacity in BTU/hr = Watts * 3.41214.
Important Legal & Educational Disclaimer
This architectural and HVAC engineering tool calculates steady-state building envelope heat transfer.
This calculator is designed for educational and informational purposes only based on public statutory frameworks. The outputs do not constitute binding financial, tax, or legal advice. We assume no liability for decisions made based on these estimations. Always verify with the relevant official authorities or a certified professional advisor.
Frequently Asked Questions
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