The Effect of Shading Factor for Single and Double Glazing According to Solar Heat Gain / Window Heat Loss Ratio in Turkey for Residential Buildings

Abstract

In this study, solar heat gains due to solar radiation and heat losses due to air temperature difference between outdoor and indoor from single and double glazed windows for the heating period in residential buildings were determined and their ratios were calculated. For five climate zones in Turkey determined by Turkish Building Insulation Standard (TS 825); the heating months were identified for the south, north, and east-west directions. The reference indoor temperature value for heating is 19°C. It is accepted that heating will be performed in the months when the outdoor air temperatures are below this temperature. The warmest climate zone is the first zone and the coldest climate zone is the fifth zone. July has the highest air temperature month for all climate zones and January has the lowest. The highest value of solar radiation occurs in June and the lowest in December. The effects of the shading factor and the number of layers for the windows were found in the calculations. In order to find the effect of shading factor, the shading factor for discrete and adjacent buildings and heat transfer coefficients for single and double glazing were determined from TS 825. Then, the solar heat gains, window heat losses and their ratios were determined by using the shading factor for discrete and adjacent buildings and without shading factor for single and double glazing. It was calculated that the solar heat gain/window heat loss ratio was higher in double glazed windows. It means that benefit from solar energy for double layer glazing is much more than single layer glazing for heating period.