Solar Heat Transmission through Windows
Solar heat gain through windows with roller shades, vertical blinds and Venetian blinds
Sun Radiation through Windows
Heat gain from sun radiation through windows can be controlled with shades or blinds.
|
Type of Shading | Transmitted Solar Energy (%) | Reflected Solar Energy (%) | Absorbed Solar Energy (%) |
|---|---|---|---|
| Single or double glass without shading | 75 - 80 | 10 - 20 | 10 - 20 |
| Vertical Blinds | 5 | 40 - 60 | 35 - 55 |
| Venetian Blinds | 0 | 23 | 77 |
| Roller Shades | < 25 | 15 - 80 | 20 - 65 |
Effect of Shading compared with unshaded Window
| Types of Shading | Fraction of Gain through Unshaded Window |
|---|---|
| Unshaded Window | 1.00 |
| Inside roller shade - half-drawn | 0.80 |
| Inside roller shade - fully-drawn | 0.62 |
| Inside venetian blind | 0.65 |
| Canvas awning | 0.30 |
| Outside shading screen - solar altitude 20o | 0.38 |
| Outside shading screen - solar altitude 30o | 0.25 |
| Outside shading screen - solar altitude 40o | 0.18 |
