Calculating the Effect of External Shading on the Solar Heat Gain Coefficient of Windows

Publication Type

Conference Paper

Date Published

08/2017

LBNL Report Number

LBNL-2001057

Abstract

Current prescriptive building codes have limited ways to account for the effect of solar shading, such as overhangs and awnings, on window solar heat gains. We propose two new indicators, the adjusted Solar Heat Gain Coefficient (aSHGC) which accounts for external shading while calculating the SHGC of a window, and a weighted SHGC (SHGCw) which provides a seasonal SHGC weighted by solar intensity. We demonstrate a method to calculate these indices using existing tools combined with additional calculations. The method is demonstrated by calculating the effect of an awning on a clear double glazing in New Delhi. 

Conference Name

Building Simulation 2017

Year of Publication

2017

Conference Location

San Francisco, CA