Window Heat Gain Calculator

Calculate solar and conductive heat gain through windows using SHGC, U-factor, and orientation.

Total fenestration area.
ft²
Window U-factor (0.25-1.2 typical).
BTU/hr·ft²·°F
Solar Heat Gain Coefficient (0-1).
Design outdoor temperature.
°F
Design indoor temperature.
°F
Peak solar intensity for orientation (100-250 BTU/hr·ft²).
BTU/hr·ft²

Results

Conductive Heat Gain-BTU/hr
Solar Heat Gain-BTU/hr
Total Window Heat Gain-BTU/hr
Cooling Load-tons
References: ASHRAE Fundamentals Chapter 15: Fenestration; ASHRAE Standard 90.1; NFRC 100/200 Rating Standards