A new method to designing window based on energy consumption

The window is an external envelope of the building that has more effect on the building energy consumption and human thermal comfort. So, calculating of window heat transfer is an important task. Since, calculating of the window energy transfer is difficult and must be calculated with the computer simulation, simple equations are necessary to estimate the window energy transfer and to compare the different window types. In this study, using computer simulation, a new equation has been presented to calculate double pane glazing window energy transfer. Using this equation, the window parameters can be designed based on the minimum window energy transfer. Also to compare the different window types (with or without overhang) a coefficient as "Efficiency Coefficient" has been defined. The result show that the window energy transfer decreases with the Efficiency Coefficient decreasing. Therefore, this coefficient can be used as a criterion to select the optimum window based on yearly minimum energy consumption.